82 results on '"Xianfu Wu"'
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2. Effect of transmission characteristics of femtosecond laser focusing on micro-/nanostructure morphology of titanium alloy
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Lin Song, Yaowen He, Xianfu Wu, Haiyan Tao, and Jingquan Lin
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Physics ,QC1-999 - Abstract
Various types of micro-/nanostructures can be fabricated by femtosecond laser irradiation on metal surfaces. It has received extensive attention and research because of its potential application value. In this paper, the effect of laser focusing position on the micro-/nanostructure formation on the surface of a titanium alloy (TC4) was systematically researched. The experimental results show that, in the process of femtosecond laser focusing, a spatial distribution of laser energy with a narrower beam center and a ring around the beam is formed in front of the geometric focus and the distribution of laser energy changes along the laser transmission direction. This property can affect the morphology of the micro-/nanostructure on the surface of irradiated materials. It is believed that the new spatial distribution of laser fluence caused by focusing is due to the nonlinear process of plasma defocus and laser self-focusing caused by multi-photon or tunnel ionization in front of the target by focusing the femtosecond laser. The discovery of the nonlinear characteristics of the focused femtosecond laser and the application of the unique energy spatial distribution to the surface morphology of the fabricated surface put forward a new idea for the direct fabrication of micro-/nanostructures via femtosecond laser, which has certain significance for the development of micro-/nanofabrication technology of femtosecond lasers.
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- 2023
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3. Immunosuppressive Sesquiterpene Pyridine Alkaloids from Tripterygium wilfordii Hook. f.
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Yadan Wang, Jiangong Yan, Zhongmou Zhang, Minghui Chen, Xianfu Wu, and Shuangcheng Ma
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sesquiterpene pyridine alkaloids ,Tripterygium wilfordii ,immunosuppressive ,Organic chemistry ,QD241-441 - Abstract
Tripterygium wilfordii Hook. f. is a well-known traditional Chinese medicine used to treat autoimmune diseases. Sesquiterpene pyridine alkaloids (SPAs) are a major class of components found in this herb that have piqued the interest of researchers due to their complex and diverse structures as well as significant biological activities. In this study, ten new SPAs, wilfordatine A–J (1–10), were isolated from the roots of T. wilfordii, along with ten known analogues (11–20). Their structures were primarily elucidated by extensive 1D and 2D NMR spectroscopic analysis. To search for more immunosuppressive ingredients related to the clinical efficacy of T. wilfordii, the total alkaloids (TA) and compounds 4, 5, and 9–16 were tested for their inhibitory effects on nuclear factor-kappa B (NF-κB) pathway in Lipopolysaccharide (LPS) induced HEK293/NF-κB-Luc cells. Among them, TA, compounds 5, 11, and 16 showed potent immunosuppressive activity, with IC50 values of 7.25 μg/mL, 8.75 μM, 0.74 μM, and 15.66 μM, respectively, and no influence on the cell viability at a concentration of 100 μg/mL (TA) or 100 μM (5, 11, and 16). Accordingly, TA, 5, 11, and 16, especially 11, were identified as promising candidates for further investigation into their potential use as immunosuppressive agents.
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- 2022
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4. Comprehensive Evaluation of the Quality of Tripterygium Glycosides Tablets Based on Multi-Component Quantification Combined with an In Vitro Biological Assay
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Yadan Wang, Zhong Dai, Jiangong Yan, Xianfu Wu, and Shuangcheng Ma
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Triptergium glycosides tablets (TGTs) ,RRLC–ESI–MS/MS ,anti-inflammatory activity ,cytotoxicity ,quality consistency ,triptolide ,Organic chemistry ,QD241-441 - Abstract
Tripterygium glycosides tablets (TGTs) are widely used in clinical practice to treat rheumatoid arthritis and other autoimmune diseases, with significant beneficial effects but also high toxicity, necessitating rigorous quality evaluation and control. In current study, a rapid resolution liquid chromatography tandem electrospray ionization triple quadrupole mass spectrometry (RRLC–ESI–MS/MS) method was developed and validated for the quantitative analysis of 14 components of ten batches of TGTs produced by different manufacturers, including four diterpenoids, three triterpenoids, and seven sesquiterpene alkaloids. Meanwhile, the NO inhibition effects of these TGTs were evaluated in LPS-induced RAW264.7 cells for their downstream anti-inflammatory activities, as well as their cytotoxicity. The results indicate that the TGTs from different manufacturers showed poor quality consistency, as evidenced by large variations in chemical profiles and biological effects, which may increase the risks associated with clinical use. To improve the quality status of TGTs, it is crucial to identify indicator components whose characterization can accurately reflect the efficacy and toxicity of TGTs from which they were derived. Our study reveals that triptolide, triptoquinone B, celastrol, and demethylzelaysteral considerably contributed to the anti-inflammatory activity and/or cytotoxicity of TGTs, implying that they should be further investigated as candidate indicator components for TGT quality control.
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- 2022
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5. Novel mass spectrometry based detection and identification of variants of rabies virus nucleoprotein in infected brain tissues.
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Matthew Reed, Olga Stuchlik, William C Carson, Lillian Orciari, Pamela A Yager, Victoria Olson, Yu Li, Xianfu Wu, Jan Pohl, and Panayampalli Subbian Satheshkumar
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
Human rabies is an encephalitic disease transmitted by animals infected with lyssaviruses. The most common lyssavirus that causes human infection is rabies virus (RABV), the prototypic member of the genus. The incubation period of RABV in humans varies from few weeks to several months in some instances. During this prodromal period, neither antibodies nor virus is detected. Antibodies, antigen and nucleic acids are detectable only after the onset of encephalitic symptoms, at which point the outcome of the disease is nearly 100% fatal. Hence, the primary intervention for human RABV exposure and subsequent post-exposure prophylaxis relies on testing animals suspected of having rabies. The most widely used diagnostic tests in animals focus on antigen detection, RABV-encoded nucleoprotein (N protein) in brain tissues. N protein accumulates in the cytoplasm of infected cells as large and granular inclusions, which are visualized in infected brain tissues by immuno-microscopy using anti-N protein antibodies. In this study, we explored a mass spectrometry (MS) based method for N protein detection without the need for any specific antibody reagents or microscopy. The MS-based method described here is unbiased, label-free, requires no amplification and determines any previously sequenced N protein available in the database. The results demonstrate the ability of MS/MS based method for N protein detection and amino acid sequence determination in animal diagnostic samples to obtain RABV variant information. This study demonstrates a potential for future developments of rabies diagnostic tests based on MS platforms.
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- 2018
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6. A high throughput neutralization test based on GFP expression by recombinant rabies virus.
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Jillybeth Burgado, Lauren Greenberg, Mike Niezgoda, Amrita Kumar, Victoria Olson, Xianfu Wu, and Panayampalli Subbian Satheshkumar
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
The effectiveness of rabies vaccination in both humans and animals is determined by the presence of virus neutralizing antibodies (VNAs). The Rapid Fluorescent Focus Inhibition Test (RFFIT) is the method traditionally used for detection and quantification of VNAs. It is a functional in vitro test for assessing the ability of antibodies in serum to bind and prevent infection of cultured cells with rabies virus (RABV). The RFFIT is a labor intensive, low throughput and semi-quantitative assay performed by trained laboratorians. It requires staining of RABV-infected cells by rabies specific fluorescent antibodies and manual quantification of fluorescent fields for titer determination. Although the quantification of fluorescent fields observed in each sample is recorded, the corresponding images are not stored or captured to be used for future analysis. To circumvent several of these disadvantages, we have developed an alternative, automated high throughput neutralization test (HTNT) for determination of rabies VNAs based on green fluorescent protein (GFP) expression by a recombinant RABV and compared with the RFFIT. The HTNT assay utilizes the recombinant RABV ERA variant expressing GFP with a nuclear localization signal (NLS) for efficient quantification. The HTNT is a quantitative method where the number of RABV-infected cells are determined and the images are stored for future analysis. Both RFFIT and HTNT results correlated 100% for a panel of human and animal positive and negative rabies serum samples. Although, the VNA titer values are generally agreeable, HTNT titers tend to be lower than that of RFFIT, probably due to the differences in quantification methods. Our data demonstrates the potential for HTNT assays in determination of rabies VNA titers.
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- 2018
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7. Inactivated Rabies Virus-Vectored Immunocontraceptive Vaccine in a Thermo-Responsive Hydrogel Induces High and Persistent Antibodies against Rabies, but Insufficient Antibodies against Gonadotropin-Releasing Hormone for Contraception
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Xianfu Wu, Yong Yang, Chantal Kling, Laurie Seigler, Nadia F. Gallardo-Romero, Brock E. Martin, Todd G. Smith, and Victoria A. Olson
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gonadotropin-releasing hormone (GnRH) ,immunocontraceptive vaccine ,rabies virus ,ERA-2GnRH ,chitosan ,thermo-responsive hydrogel ,nonsurgical sterilization ,Medicine - Abstract
Rabies is preventable through vaccination, but the need to mount annual canine vaccination campaigns presents major challenges in rabies control and prevention. The development of a rabies vaccine that ensures lifelong immunity and animal population management in one dose could be extremely advantageous. A nonsurgical alternative to spay/neuter is a high priority for animal welfare, but irreversible infertility in one dose has not been achieved. Towards this goal, we developed a rabies virus-vectored immunocontraceptive vaccine ERA-2GnRH, which protected against rabies virus challenge and induced >80% infertility in mice after three doses in a live, liquid-vaccine formulation (Wu et al., 2014). To improve safety and use, we formulated an inactivated vaccine in a thermo-responsive chitosan hydrogel for one-dose delivery and studied the immune responses in mice. The hydrogel did not cause any injection site reactions, and the killed ERA-2GnRH vaccine induced high and persistent rabies virus neutralizing antibodies (rVNA) in mice. The rVNA in the hydrogel group reached an average of 327.40 IU/mL, more than 200 times higher than the liquid vaccine alone. The Gonadotropin-releasing hormone (GnRH) antibodies were also present and lasted longer in the hydrogel group, but did not prevent fertility in mice, reflecting a possible threshold level of GnRH antibodies for contraception. In conclusion, the hydrogel facilitated a high and long-lasting immunity, and ERA-2GnRH is a promising dual vaccine candidate. Future studies will focus on rabies protection in target species and improving the anti-GnRH response.
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- 2019
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8. Molecular Epidemiology of Rabies in Southern People’s Republic of China
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Xiao-Yan Tao, Qing Tang, Hao Li, Zhao-Jun Mo, Hong Zhang, Ding-Ming Wang, Qiang Zhang, Miao Song, Andres Velasco-Villa, Xianfu Wu, Charles E. Rupprecht, and Guo-Dong Liang
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Molecular epidemiology ,nucleoprotein ,rabies ,epidemic ,China ,viruses ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
In recent years, the number of human rabies cases in the People’s Republic of China has increased during severe epidemics in 3 southern provinces (Guizhou, Guangxi, and Hunan). To analyze the causes of the high incidence of human rabies in this region, during 2005–2007, we collected 2,887 brain specimens from apparently healthy domestic dogs used for meat consumption in restaurants, 4 specimens from suspected rabid dogs, and 3 from humans with rabies in the 3 provinces. Partial nucleoprotein gene sequences were obtained from rabies-positive specimens. Phylogenetic relationships and distribution of viruses were determined. We infer that the spread of rabies viruses from high-incidence regions, particularly by long-distance movement or transprovincial translocation of dogs caused by human-related activities, may be 1 cause of the recent massive human rabies epidemics in southern China.
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- 2009
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9. Reemerging Rabies and Lack of Systemic Surveillance in People’s Republic of China
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Xianfu Wu, Rongliang Hu, Yongzhen Zhang, Guanmu Dong, and Charles E. Rupprecht
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Rabies ,viruses ,carrier-dog phenomenon ,China ,counterfeit vaccines ,seroconversion testing ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Rabies is a reemerging disease in China. The high incidence of rabies leads to numerous concerns: a potential carrier-dog phenomenon, undocumented transmission of rabies virus from wildlife to dogs, counterfeit vaccines, vaccine mismatching, and seroconversion testing in patients after their completion of postexposure prophylaxis (PEP). These concerns are all scientifically arguable given a modern understanding of rabies. Rabies reemerges periodically in China because of high dog population density and low vaccination coverage in dogs. Mass vaccination campaigns rather than depopulation of dogs should be a long-term goal for rabies control. Seroconversion testing after vaccination is not necessary in either humans or animals. Human PEP should be initiated on the basis of diagnosis of biting animals. Reliable national systemic surveillance of rabies-related human deaths and of animal rabies prevalence is urgently needed. A laboratory diagnosis–based epidemiologic surveillance system can provide substantial information about disease transmission and effective prevention strategies.
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- 2009
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10. Rabies in Ferret Badgers, Southeastern China
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Shoufeng Zhang, Qing Tang, Xianfu Wu, Ye Liu, Fei Zhang, Charles E. Rupprecht, and Rongliang Hu
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Rabies ,ferret badgers ,rabies virus ,retrospective epidemiological surveillance ,spillover ,viruses ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Ferret badger–associated human rabies cases emerged in China in 1994. We used a retrospective epidemiologic survey, virus isolation, laboratory diagnosis, and nucleotide sequencing to document its reemergence in 2002–2008. Whether the cause is spillover from infected dogs or recent host shift and new reservoir establishment requires further investigation.
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- 2009
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11. Screening, characterization, and determination of suspected additives bimatoprost and latanoprost in cosmetics using NMR and LC–MS methods
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Yong Lu, Yu He, Xinran Wang, Haiyan Wang, Qianqian Qiu, Baojin Wu, and Xianfu Wu
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Biochemistry ,Analytical Chemistry - Published
- 2023
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12. Construction of a Library of Fully Protected Oligosaccharide for Preparing Various Subtypes of Chondroitin Sulfate
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Longlong Jin, Qi Liu, Shuang Yang, Huimin Sun, Zhehui Zhao, Yong Lu, and Xianfu Wu
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- 2023
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13. Identification and Characterization of Forced Degradation Products of 5‑Hydroxymethyl-2-Furaldehyde (5-Hmf) by Hplc and Lc-Ltq/Orbitrap Studies
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Yong Lu, Yaqing Guo, Yajun Zhang, Huimin Sun, Shuangcheng ma, and Xianfu Wu
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- 2023
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14. Identification and characterization of forced degradation products of 5-hydroxymethyl-2-furaldehyde (5-HMF) by HPLC, LC-LTQ/Orbitrap and NMR studies
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Yong Lu, Yaqing Guo, Yajun Zhang, Huimin Sun, and Xianfu Wu
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Clinical Biochemistry ,Drug Discovery ,Pharmaceutical Science ,Spectroscopy ,Analytical Chemistry - Published
- 2023
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15. Front Cover: Characterization and determination of benvitimod, an unknown risk substance in cosmetics, using nuclear magnetic resonance spectroscopy and HPLC‒MS/MS
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Xinran Wang, Haiyan Wang, Xianfu Wu, and Yong Lu
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Filtration and Separation ,Analytical Chemistry - Published
- 2022
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16. Characterization and determination of benvitimod, an unknown risk substance in cosmetics, using nuclear magnetic resonance spectroscopy and HPLC-MS/MS
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Xinran Wang, Haiyan Wang, Xianfu Wu, and Yong Lu
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Magnetic Resonance Spectroscopy ,Tandem Mass Spectrometry ,Filtration and Separation ,Cosmetics ,Chromatography, High Pressure Liquid ,Analytical Chemistry - Abstract
Ultrahigh-performance liquid chromatography-tandem high-resolution mass spectrometry, combined with preparative chromatography and nuclear magnetic resonance spectroscopy, a new method for identifying unknown risk substance structures in cosmetics has been established. Moreover, HPLC-MS/MS was developed for the determination of benvitimod in cosmetics. The sample was collected in ultrahigh-performance liquid chromatography-tandem high-resolution mass spectrometry, and the molecular formula of the unknown was obtained as C
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- 2022
17. Synthesis and antibacterial activity of novel 2‑fluoro ketolide antibiotics with 11,12‑quinoylalkyl side chains
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Longlong, Jin, Xiaoxi, Zhang, Zhigang, Luo, Xianfu, Wu, and Zhehui, Zhao
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Organic Chemistry ,Clinical Biochemistry ,Drug Discovery ,Pharmaceutical Science ,Molecular Medicine ,Molecular Biology ,Biochemistry - Abstract
A series of novel 2-fluoro ketolide antibiotics with 11,12-quinoylalkyl side chains derived from telithromycin and cethromycin were designed and synthesized. The corresponding targets 2a-o were tested for their in vitro activities against a series of macrolide-sensitive and macrolide-resistant pathogens. Some of them showed a similar antibacterial spectrum and comparable or slightly better activity to telithromycin. Among them, compounds 2g and 2k, displayed excellent activities against macrolide-sensitive and macrolide-resistant pathogens.
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- 2023
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18. Feline herpesvirus vectored-rabies vaccine in cats: A dual protection
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Xianfu Wu, Rongliang Hu, Lijuan Mi, Teng Chen, Shoufeng Zhang, Ye Liu, Xuefei Sun, Xintao Zhou, Wei Qiu, Victoria A. Olson, and Yu Qi
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Rabies ,Genetic Vectors ,030231 tropical medicine ,Gene Expression ,Antibodies, Viral ,Cat Diseases ,medicine.disease_cause ,Recombinant virus ,Cell Line ,03 medical and health sciences ,Dogs ,0302 clinical medicine ,Rabies vaccine ,Genes, Reporter ,Neutralization Tests ,medicine ,Animals ,Humans ,Varicellovirus ,030212 general & internal medicine ,Homologous Recombination ,Neutralizing antibody ,Vaccines, Synthetic ,CATS ,General Veterinary ,General Immunology and Microbiology ,biology ,business.industry ,Rabies virus ,Public Health, Environmental and Occupational Health ,medicine.disease ,Antibodies, Neutralizing ,Virology ,Vaccination ,Titer ,Infectious Diseases ,Rabies Vaccines ,Cats ,biology.protein ,Molecular Medicine ,Immunization ,business ,medicine.drug - Abstract
In China, cats cause about 5% of human rabies cases. Rabies control in cats plays a role in achieving the ultimate goal of elimination of dog rabies-mediated human deaths. However, there is no cat-specific rabies vaccine in China yet. In this study, we constructed a recombinant rabies vaccine by using a felid herpesvirus 1 (FHV-1) isolate, and deleted the gI/E in the FHV-1 and replaced the region with a glycoprotein (G) of rabies virus (RABV) strain BD06 through homologous recombination. The recombinant virus FHV-RVG was recovered and purified, and the expression of RABV glycoprotein was verified by indirect immunofluorescent assay. For potency in cats, each animal was inoculated intranasally with 1 ml FHV-RVG at 106.5 TCID50. Blood samples were collected at defined intervals for antibody titration. The animals were challenged by herpes and rabies after completion of vaccination on day 180 and day 194, respectively. Our results demonstrated all vaccinated cats generated antibodies against both FHV-1 and RABV, and reached an arbitrary protective titer > 0.5 IU/ml for rabies viral neutralizing antibody (VNA) by day 14 post inoculation (dpi) and titer peaked on 30 dpi with VNA at 24.5 ± 10.23 IU/ml. All vaccinated cats presented no clinical signs of FHV-1 infection and survived rabies challenge, while the control cats had severe rhinotracheitis and died from rabies after challenge. All this demonstrated that the FHV-based recombinant vaccine is effective in protection against both FHV-1 and RABV infections.
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- 2019
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19. Quality control and product differentiation of LMWHs marketed in China using
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Haipeng, Jiang, Xinbai, Li, Minglan, Ma, Xiaochun, Shi, and Xianfu, Wu
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Quality Control ,Magnetic Resonance Spectroscopy ,Anticoagulants ,Chemometrics ,Enoxaparin ,Heparin, Low-Molecular-Weight - Abstract
Low molecular weight heparins (LMWHs) are heterogeneous mixtures of glycosaminoglycan chains composed of mixture of different lengths and substitution patterns. Structural characterization and quality control of LMWHs have always been challenging. The Chinese drug regulatory authorities have been committed to improve the supervision standards of LMWHs to better regulate the quality and safety of LMWHs in current Chinese market. In the present paper, 80 batches of three types LMWHs (dalteparin, enoxaparin and naldroparin) marketed in China from different manufacturers were studied by
- Published
- 2021
20. Laser-assisted skin delivery of immunocontraceptive rabies nanoparticulate vaccine in poloxamer gel
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Wael Gamal, Amit Bansal, Victoria A. Olson, Xianfu Wu, Martin J. D'Souza, and Ipshita Menon
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Rabies ,medicine.medical_treatment ,Pharmaceutical Science ,02 engineering and technology ,Poloxamer ,CD8-Positive T-Lymphocytes ,030226 pharmacology & pharmacy ,Flow cytometry ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Immune system ,Adjuvants, Immunologic ,medicine ,Animals ,Humans ,Immunocontraception ,Mice, Inbred BALB C ,medicine.diagnostic_test ,biology ,business.industry ,Lasers ,Vaccination ,021001 nanoscience & nanotechnology ,medicine.disease ,Cytokine ,Rabies Vaccines ,Immunology ,biology.protein ,Antibody ,0210 nano-technology ,business ,Adjuvant - Abstract
A painless skin delivery of vaccine for disease prevention is of great advantage in improving compliance in patients. To test this idea as a proof of concept, we utilized a pDNA vaccine construct, pDNAg333-2GnRH that has a dual function of controlling rabies and inducing immunocontraception in animals. The pDNA was administered to mice in a nanoparticulate form delivered through the skin using the P.L.E.A.S.E.® (Precise Laser Epidermal System) microporation laser device. Laser application was well tolerated, and mild skin reaction was healed completely in 8 days. We demonstrated that adjuvanted nanoparticulate pDNA vaccine significantly upregulated the expression of co-stimulatory molecules in dendritic cells. After topical administration of the adjuvanted nano-vaccine in mice, the high avidity serum for GnRH antibodies were induced and maintained up to 9 weeks. The induced immune response was of a mixed Th1/Th2 profile as measured by IgG subclasses (IgG2a and IgG1) and cytokine levels (IFN-γ and IL-4). Using flow cytometry, we revealed an increase of CD8+ T-cells and CD45R B cells upon the administration of the adjuvanted vaccine. Our previous study used the same pDNA nanoparticulate vaccine through an IM route, and a comparable immune response was induced using P.L.E.A.S.E. However, the vaccine dose in the current study was four-fold less than what was applied through the IM route.We concluded that laser-assisted skin vaccination has a potential of becoming a safe and reliable vaccination tool for rabies vaccination in animals or even in humans for pre- or post-exposure prophylaxis.
- Published
- 2020
21. Development of a relative potency test using ELISA for human rabies vaccines
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Zejun Wang, Lei You, Yaqi Ji, Darin S. Carroll, Wenli Lv, Shengli Meng, Jiaxin Yan, Yan Sun, Xianfu Wu, Jinrong Shi, and Ge-Lin Xu
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Male ,Quality Control ,0301 basic medicine ,China ,Enzyme-Linked Immunosorbent Assay ,Bioengineering ,Applied Microbiology and Biotechnology ,Mice ,03 medical and health sciences ,Rabies vaccine ,medicine ,Animals ,Humans ,Potency ,Relative potency ,Vaccine Potency ,Pharmacology ,General Immunology and Microbiology ,business.industry ,Human rabies vaccines ,General Medicine ,medicine.disease ,Virology ,030104 developmental biology ,Rabies Vaccines ,Close relationship ,Correlation analysis ,Female ,Rabies ,business ,Biotechnology ,medicine.drug - Abstract
The NIH potency test for human rabies vaccines has disadvantages for use, especially in developing countries where rabies is endemic and prophylaxis needs ample, rapid, and reliable vaccine supplies. In China, 60–75 million doses of human rabies vaccines are administered each year. Vaccine quality control is of paramount importance, as is the release of potency-validated vaccines. We intended to design an alternative to the NIH in vivo method, and developed a relative potency test using an ELISA. Using Pearson's correlation analysis, we found a close relationship between the rabies vaccine glycoprotein content in vitro and the potency values in vivo. We suggest the relative potency test developed here as a simplified method for human rabies vaccine quality control in China and a possible alternative to the NIH method.
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- 2018
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22. Characterization of rabies pDNA nanoparticulate vaccine in poloxamer 407 gel
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Amit Bansal, Martin J. D'Souza, Victoria A. Olson, and Xianfu Wu
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Surface Properties ,Drug Compounding ,Pharmaceutical Science ,Nanoparticle ,Electrophoretic Mobility Shift Assay ,Poloxamer ,02 engineering and technology ,030226 pharmacology & pharmacy ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Stability ,Polylactic Acid-Polyglycolic Acid Copolymer ,Plasmid dna ,Spectroscopy, Fourier Transform Infrared ,Vaccines, DNA ,medicine ,Animals ,Nanotechnology ,Technology, Pharmaceutical ,Lactic Acid ,Chitosan ,Drug Carriers ,Delivery vehicle ,Cationic polymerization ,Hydrogels ,Dendritic Cells ,021001 nanoscience & nanotechnology ,In vitro ,Mice, Inbred C57BL ,Drug Liberation ,Kinetics ,PLGA ,Concentration dependent ,Rabies Vaccines ,Solubility ,chemistry ,Poloxamer 407 ,Biophysics ,Nanoparticles ,0210 nano-technology ,Polyglycolic Acid ,medicine.drug - Abstract
Plasmid DNA (pDNA) vaccines have the potential for protection against a wide range of diseases including rabies but are rapid in degradation and poor in uptake by antigen-presenting cells. To overcome the limitations, we fabricated a pDNA nanoparticulate vaccine. The negatively charged pDNA was adsorbed onto the surface of cationic PLGA (poly ( d , l -lactide-co-glycolide))-chitosan nanoparticles and were used as a delivery vehicle. To create a hydrogel for sustainable vaccine release, we dispersed the pDNA nanoparticles in poloxamer 407 gel which is liquid at 4 °C and turns into soft gels at 37 °C, providing ease of administration and preventing burst release of pDNA. Complete immobilization of pDNA to cationic nanoparticles was achieved at a pDNA to nanoparticles ratio (P/N) of 1/50. Cellular uptake of nanoparticles was both time and concentration dependent and followed a saturation kinetics with Vmax of 11.389 µg/mL h and Km of 139.48 µg/mL. The in vitro release studies showed the nanoparticulate vaccine has a sustained release for up to 24 days. In summary, pDNA PLGA-chitosan nanoparticles were non-cytotoxic, their buffering capacity and cell uptake were enhanced, and sustained the release of pDNA. We expect our pDNA vaccine’s potency will be greatly improved in the animal studies.
- Published
- 2018
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23. Quality control and product differentiation of LMWHs marketed in China using 1H NMR spectroscopy and chemometric tools
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Xinbai Li, Haipeng Jiang, Xiaochun Shi, Xianfu Wu, and Minglan Ma
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1h nmr spectroscopy ,Chinese drug ,Chemistry ,media_common.quotation_subject ,Clinical Biochemistry ,Chinese market ,Pharmaceutical Science ,Biosimilar ,Product differentiation ,Analytical Chemistry ,Drug Discovery ,Quality (business) ,Biochemical engineering ,Spectroscopy ,media_common - Abstract
Low molecular weight heparins (LMWHs) are heterogeneous mixtures of glycosaminoglycan chains composed of mixture of different lengths and substitution patterns. Structural characterization and quality control of LMWHs have always been challenging. The Chinese drug regulatory authorities have been committed to improve the supervision standards of LMWHs to better regulate the quality and safety of LMWHs in current Chinese market. In the present paper, 80 batches of three types LMWHs (dalteparin, enoxaparin and naldroparin) marketed in China from different manufacturers were studied by 1H NMR experiments and chemometric analysis. The method can be used not only to monitor impurities and contaminants, but also to check the batch-to-batch consistency of each manufacture. Moreover, for the biosimilar LMWHs from different manufactures, they can be differentiated and clustered according to their slightly different structural compositions originated from production process. By using this method, the quality and safety of LMWHs marketed in China were initially assessed.
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- 2022
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24. SAFETY, IMMUNOGENICITY, AND EFFICACY OF INTRAMUSCULAR AND ORAL DELIVERY OF ERA-G333 RECOMBINANT RABIES VIRUS VACCINE TO BIG BROWN BATS (
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Amy T, Gilbert, Xianfu, Wu, Felix R, Jackson, Richard, Franka, Gary F, McCracken, and Charles E, Rupprecht
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Vaccines, Synthetic ,Rabies Vaccines ,Rabies ,Chiroptera ,Vaccination ,Administration, Oral ,Animals ,Antibodies, Neutralizing ,Injections, Intramuscular - Abstract
Attenuated strains of rabies virus (RABV) have been used for oral vaccination of wild carnivores in Europe and North America. However, some RABV vaccines caused clinical rabies in target animals. To improve the safety of attenuated RABV as an oral vaccine for field use, strategies using selection of escape mutants under monoclonal antibody neutralization pressure and reverse genetics-defined mutations have been used. We tested the safety, immunogenicity, and efficacy of one RABV construct, ERA-g333, developed with reverse genetics by intramuscular (IM) or oral (PO) routes in big brown bats (
- Published
- 2020
25. Human Rabies — Missouri, 2014
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P Drew, Pratt, Kathleen, Henschel, George, Turabelidze, Autumn, Grim, James A, Ellison, Lillian, Orciari, Pamela, Yager, Richard, Franka, Xianfu, Wu, Xiaoyue, Ma, Ashutosh, Wadhwa, Todd G, Smith, Brett, Petersen, and Miriam, Shiferaw
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Male ,Pediatrics ,medicine.medical_specialty ,Pathology ,Health (social science) ,Rabies ,Epidemiology ,Health, Toxicology and Mutagenesis ,Vital signs ,medicine.disease_cause ,01 natural sciences ,03 medical and health sciences ,Fatal Outcome ,0302 clinical medicine ,Health Information Management ,Chiroptera ,medicine ,Animals ,Humans ,Infection control ,030212 general & internal medicine ,0101 mathematics ,Missouri ,business.industry ,Public health ,010102 general mathematics ,Rabies virus ,General Medicine ,Emergency department ,Middle Aged ,medicine.disease ,Etiology ,Encephalitis ,Public Health ,business - Abstract
On September 18, 2014, the Missouri Department of Health and Senior Services (MDHSS) was notified of a suspected rabies case in a Missouri resident. The patient, a man aged 52 years, lived in a rural, deeply wooded area, and bat sightings in and around his home were anecdotally reported. Exposure to bats poses a risk for rabies. After two emergency department visits for severe neck pain, paresthesia in the left arm, upper body tremors, and anxiety, he was hospitalized on September 13 for encephalitis of unknown etiology. On September 24, he received a diagnosis of rabies and on September 26, he died. Genetic sequencing tests confirmed infection with a rabies virus variant associated with tricolored bats. Health care providers need to maintain a high index of clinical suspicion for rabies in patients who have unexplained, rapidly progressive encephalitis, and adhere to recommended infection control practices when examining and treating patients with suspected infectious diseases.
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- 2016
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26. SAFETY, IMMUNOGENICITY, AND EFFICACY OF INTRAMUSCULAR AND ORAL DELIVERY OF ERA-G333 RECOMBINANT RABIES VIRUS VACCINE TO BIG BROWN BATS (EPTESICUS FUSCUS)
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Xianfu Wu, Charles E. Rupprecht, Felix R. Jackson, Gary F. McCracken, Richard Franka, and Amy T. Gilbert
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Ecology ,biology ,040301 veterinary sciences ,Immunogenicity ,030231 tropical medicine ,Rabies virus ,04 agricultural and veterinary sciences ,medicine.disease ,medicine.disease_cause ,biology.organism_classification ,Virology ,law.invention ,0403 veterinary science ,Vaccination ,03 medical and health sciences ,0302 clinical medicine ,Eptesicus fuscus ,law ,medicine ,Recombinant DNA ,Rabies ,Ecology, Evolution, Behavior and Systematics - Abstract
Attenuated strains of rabies virus (RABV) have been used for oral vaccination of wild carnivores in Europe and North America. However, some RABV vaccines caused clinical rabies in target a...
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- 2020
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27. Novel mass spectrometry based detection and identification of variants of rabies virus nucleoprotein in infected brain tissues
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Olga Stuchlik, Panayampalli Subbian Satheshkumar, William C. Carson, Matthew S. Reed, Victoria A. Olson, Jan Pohl, Xianfu Wu, Lillian A. Orciari, Yu Li, and Pamela A. Yager
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0301 basic medicine ,RNA viruses ,Viral Diseases ,Physiology ,RC955-962 ,Protein Sequencing ,medicine.disease_cause ,Pathology and Laboratory Medicine ,Biochemistry ,0403 veterinary science ,Database and Informatics Methods ,Tandem Mass Spectrometry ,Arctic medicine. Tropical medicine ,Zoonoses ,Immune Physiology ,Medicine and Health Sciences ,Peptide sequence ,Mammals ,Immune System Proteins ,biology ,Brain ,Eukaryota ,04 agricultural and veterinary sciences ,Infectious Diseases ,Medical Microbiology ,Viral Pathogens ,Vertebrates ,Viruses ,Raccoons ,Public aspects of medicine ,RA1-1270 ,Antibody ,Pathogens ,Sequence Analysis ,Research Article ,Neglected Tropical Diseases ,040301 veterinary sciences ,Rabies ,Bioinformatics ,Immunology ,Sequence Databases ,Research and Analysis Methods ,Microbiology ,Virus ,Antibodies ,03 medical and health sciences ,Viral Proteins ,Rabies Virus ,Antigen ,Amino Acid Sequence Analysis ,medicine ,Humans ,Animals ,Molecular Biology Techniques ,Sequencing Techniques ,Lyssavirus ,Molecular Biology ,Microbial Pathogens ,Rabies virus ,Public Health, Environmental and Occupational Health ,Organisms ,Biology and Life Sciences ,Proteins ,medicine.disease ,biology.organism_classification ,Tropical Diseases ,Virology ,Nucleoprotein ,030104 developmental biology ,Nucleoproteins ,Biological Databases ,Amniotes ,biology.protein ,Tissue Proteins - Abstract
Human rabies is an encephalitic disease transmitted by animals infected with lyssaviruses. The most common lyssavirus that causes human infection is rabies virus (RABV), the prototypic member of the genus. The incubation period of RABV in humans varies from few weeks to several months in some instances. During this prodromal period, neither antibodies nor virus is detected. Antibodies, antigen and nucleic acids are detectable only after the onset of encephalitic symptoms, at which point the outcome of the disease is nearly 100% fatal. Hence, the primary intervention for human RABV exposure and subsequent post-exposure prophylaxis relies on testing animals suspected of having rabies. The most widely used diagnostic tests in animals focus on antigen detection, RABV-encoded nucleoprotein (N protein) in brain tissues. N protein accumulates in the cytoplasm of infected cells as large and granular inclusions, which are visualized in infected brain tissues by immuno-microscopy using anti-N protein antibodies. In this study, we explored a mass spectrometry (MS) based method for N protein detection without the need for any specific antibody reagents or microscopy. The MS-based method described here is unbiased, label-free, requires no amplification and determines any previously sequenced N protein available in the database. The results demonstrate the ability of MS/MS based method for N protein detection and amino acid sequence determination in animal diagnostic samples to obtain RABV variant information. This study demonstrates a potential for future developments of rabies diagnostic tests based on MS platforms., Author summary Although rabies is almost always fatal after the symptom onset phase, it can be prevented by timely administration of post-exposure prophylaxis (PEP), which involves passive antibody transfer and vaccination. One of the primary laboratory confirmatory tests for RABV infection is antigen detection, directed against the RABV encoded N protein using anti-N protein specific antibodies, in central nervous system (CNS) tissue samples of animals. This immuno-microscopy based detection utilizes either fluorescent tags (direct detection) or chromogenic substrates (indirect) in brain impressions from animals in which rabies is suspected. In this study, we explored the detection of N protein by a novel mass spectrometry (MS) based method that is label-free and does not require target amplification. The MS method specifically detected N protein in brain tissue and identified RABV variants based on amino acid sequence information. To our knowledge, this is the first report of an N protein detection method that does not utilize either antibodies or microscopy. This method provides an alternative platform for the development of future rabies diagnostic tests.
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- 2018
28. Glycoprotein from street rabies virus BD06 induces early and robust immune responses when expressed from a non-replicative adenovirus recombinant
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Shuchao Wang, Chenglong Sun, Fei Zhang, Ye Liu, Ying Wang, Shoufeng Zhang, Xiaozhuo Zhang, Rongliang Hu, and Xianfu Wu
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Genetic Vectors ,Biology ,Antibodies, Viral ,Vaccines, Attenuated ,medicine.disease_cause ,law.invention ,Mice ,Immune system ,Viral Envelope Proteins ,Antigen ,law ,Virology ,medicine ,Animals ,Seroconversion ,Neutralizing antibody ,Antigens, Viral ,Glycoproteins ,Drug Carriers ,Vaccines, Synthetic ,Adenoviruses, Human ,Rabies virus ,General Medicine ,medicine.disease ,Antibodies, Neutralizing ,Survival Analysis ,Rabies Vaccines ,biology.protein ,Recombinant DNA ,Female ,Rabies ,Antibody - Abstract
The rabies virus (RABV) glycoprotein (G) is responsible for inducing neutralizing antibodies against rabies virus. Development of recombinant vaccines using the G genes from attenuated strains rather than street viruses is a regular practice. In contrast to this scenario, we generated three human adenovirus type 5 recombinants using the G genes from the vaccine strains SRV9 and Flury-LEP, and the street RABV strain BD06 (nrAd5-SRV9-G, nrAd5-Flury-LEP-G, and nrAd5-BD06-G). These recombinants were non-replicative, but could grow up to ~10(8) TCID50/ml in helper HEK293AD cells. Expression of the G protein was verified by immunostaining, quantitative PCR and cytometry. Animal experiments revealed that immunization with nrAd5-BD06-G can induce a higher seroconversion rate, a higher neutralizing antibody level, and a longer survival time after rabies virus challenge in mice when compared with the other two recombinants. Moreover, the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) was significantly higher in mice immunized with nrAd5-BD06-G, which might also contribute to the increased protection. These results show that the use of street RABV G for non-replicative systems may be an alternative for developing effective recombinant rabies vaccines.
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- 2015
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29. Potential Cancer Prevention and Treatment by Silencing the Killer Cell Immunoglobulin-like Receptor Gene in Natural Killer Cells Derived from Induced Pluripotent Stem Cells
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Yunlong, Qin, Christina, Hutson, Xianfu, Wu, Jingyao, Xu, and Darin, Carroll
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Article - Abstract
Cancer immunosurveillance is an important host protection process, monitoring the presence of irregular cells that could potentially transform into tumor cells, effectively clearing the body of transformed tumor cells at their earliest stages, and thus maintaining regular cellular homeostasis. Natural killer (NK) cells are effector lymphocytes of the innate immune system, playing a critical role in surveillance for tumor cells, while also eliminating virally infected cells. The significance of the anti-tumor role of NK cells was recently further verified by findings that immunosuppression in most cancer patients is not perceptible until late stages. NK cells express the low-affinity Fc-activating receptor, CD16, and the inhibitory receptor, killer cell immunoglobulin-like receptor (KIR). Consequently, activation of NK cells is determined by the balance of inhibitory and activating receptor stimulation. Here, we propose establishing an induced pluripotent stem cell (iPSC)-derived NK cell line with KIR gene knockout or knockdown as a possible regimen to treat and prevent cancer. We further postulate that an optimal mixture of NK iPSCs with and without KIR gene knockout, would reach a maximum antitumor activity, with minimal side effects. We also discuss the possible advantages of KIR-knockout NK iPSCs for adoptive immunotherapy in patients with cancer.
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- 2017
30. Assessment of the immunogenicity of rabies vaccine preserved by vaporization and delivered to the duodenal mucosa of gray foxes (Urocyon cinereoargenteus)
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Brianna L. Skinner, Ashutosh Wadhwa, Todd G. Smith, Victor Bronshtein, James A. Ellison, Xianfu Wu, Cathleen A. Hanlon, Gregory L. Langham, and Richard Franka
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Male ,Saliva ,Duodenum ,animal diseases ,030231 tropical medicine ,Administration, Oral ,Foxes ,Animals, Wild ,Biology ,medicine.disease_cause ,Vaccines, Attenuated ,Article ,03 medical and health sciences ,0302 clinical medicine ,Rabies vaccine ,Immunogenicity, Vaccine ,Intestinal mucosa ,parasitic diseases ,medicine ,Animals ,030212 general & internal medicine ,Viral shedding ,Intestinal Mucosa ,Antigens, Viral ,Duodenoscopy ,General Veterinary ,Immunogenicity ,Rabies virus ,food and beverages ,General Medicine ,medicine.disease ,Vaccination ,Rabies Vaccines ,Immunology ,population characteristics ,Rabies ,Female ,Volatilization ,medicine.drug - Abstract
OBJECTIVE To assess the immunogenicity of thermostable live-attenuated rabies virus (RABV) preserved by vaporization (PBV) and delivered to the duodenal mucosa of a wildlife species targeted for an oral vaccination program. ANIMALS 8 gray foxes (Urocyon cinereoargenteus). PROCEDURES Endoscopy was used to place RABV PBV (n = 3 foxes), alginate-encapsulated RABV PBV (3 foxes), or nonpreserved RABV (2 foxes) vaccine into the duodenum of foxes. Blood samples were collected weekly to monitor the immune response. Saliva samples were collected weekly and tested for virus shedding by use of a conventional reverse-transcriptase PCR assay. Foxes were euthanized 28 days after vaccine administration, and relevant tissues were collected and tested for presence of RABV. RESULTS 2 of 3 foxes that received RABV PBV and 1 of 2 foxes that received nonpreserved RABV seroconverted by day 28. None of the 3 foxes receiving alginate-encapsulated RABV PBV seroconverted. No RABV RNA was detected in saliva at any of the time points, and RABV antigen or RNA was not detected in any of the tissues obtained on day 28. None of the foxes displayed any clinical signs of rabies. CONCLUSIONS AND CLINICAL RELEVANCE Results for this study indicated that a live-attenuated RABV vaccine delivered to the duodenal mucosa can induce an immune response in gray foxes. A safe, potent, thermostable RABV vaccine that could be delivered orally to wildlife or domestic animals would enhance current rabies control and prevention efforts.
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- 2017
31. The feasibility of rabies virus-vectored immunocontraception in a mouse model
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Xianfu Wu, William C. Carson, Charles E. Rupprecht, Min Wang, Richard Franka, and Todd G. Smith
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medicine.medical_treatment ,Immunology ,Gonadotropin-releasing hormone ,Biology ,medicine.disease_cause ,Recombinant virus ,Microbiology ,Epitope ,medicine ,Duck embryo vaccine ,Immunocontraception ,Animal population management ,Rabies virus ,lcsh:RM1-950 ,Public Health, Environmental and Occupational Health ,medicine.disease ,Virology ,Infectious Diseases ,lcsh:Therapeutics. Pharmacology ,Reverse genetics ,Immunocontraceptive vaccine ,Rabies ,Non-surgical sterilization ,Adjuvant - Abstract
Immunocontraceptive vaccines may be an alternative to surgical sterilization. Dual rabies vaccination and dog population management is a helpful tool for rabies prevention. A synthetic gonadotropin-releasing hormone (GnRH) peptide coupled to a carrier protein or T cell epitope is efficacious in inducing immunocontraception in a variety of mammals. However, virus-vectored GnRH recombinant vaccines have advantages over the conjugation method. In a previous in vitro study, we were able to insert a GnRH-coding sequence into the rabies virus (RABV) glycoprotein (G) gene, and the recombinant viruses grew to high titers in cells. Here, we further focused on the RABV G in accepting various copy numbers of GnRH. We demonstrated although RABV G protein with up to 4 copies of GnRH was well expressed, the recombinant virus was recovered only when 2 copies of GnRH (20 amino acids) were incorporated into the G, indicating a possible insertion limit in making a full infectious clone. The investigation provides insight into the utility of RABV G as a carrier for small peptides and its suitability for vaccine studies. Following our previous study, we selected ERAg3p/2GnRH and tested the construct in mice. The vaccine induced ⩾80% infertility after three doses without any adjuvant, in live (8 of 10 mice infertility) or inactivated (13 of 14 mice infertility) formulations; while the pregnancy rate was 100% (10 of 10 mice) in the controls. This initial success of immunocontraception in mice is promising, and we are now optimizing the vaccine formulation by using adjuvants and exploring novel delivery methods to minimize the dosage.
- Published
- 2014
32. α-Pyrones and Pyranes from the Plant Pathogenic Fungus Pestalotiopsis scirpina
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Yongsheng Che, Xuejun Jiang, Xianfu Wu, Jian Li, Liang-Dong Guo, Yu Feng, and Gang Ding
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Circular dichroism ,Stereochemistry ,Chemistry ,Organic Chemistry ,Organic chemistry ,Physical and Theoretical Chemistry ,Pathogenic fungus ,Pestalotiopsis scirpina ,Cytotoxicity ,Pathogen - Abstract
Three new α-pyrones, scirpyrones A–C (1–3), and four new pyranes, scirpyranes A–D (4–7), were isolated from solid cultures of the plant pathogen Pestalotiopsis scirpina. Their structures were elucidated primarily by NMR experiments. The absolute configurations of C-7 and C-2′ in 1, C-7 in 2, and C-6 and C-7 in 3 were deduced on the basis of circular dichroism (CD) data, whereas those of the secondary alcohols in 4–7 were determined by a modification of Mosher's method. Compound 1 is the first described 6-(5-oxotetrahydrofuran-2-yl)-2H-pyran-2-one. Compounds 4–6 showed significant cytotoxicity towards MCF-7 cells.
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- 2012
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33. From brain passage to cell adaptation: the road of human rabies vaccine development
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Xianfu Wu, Charles E. Rupprecht, and Todd G. Smith
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Rabies ,Immunology ,Cell Culture Techniques ,Vaccines, Attenuated ,medicine.disease_cause ,History, 21st Century ,Virus ,Rabies vaccine ,Cell adaptation ,Drug Discovery ,medicine ,Animals ,Humans ,Technology, Pharmaceutical ,High titer ,Lyssavirus ,Duck embryo vaccine ,Pharmacology ,biology ,Rabies virus ,History, 19th Century ,History, 20th Century ,medicine.disease ,biology.organism_classification ,Virology ,Rabies Vaccines ,Vaccines, Inactivated ,Molecular Medicine ,medicine.drug - Abstract
A major challenge for global rabies prevention and control is the lack of sufficient and affordable high quality vaccines. Such candidates should be pure, potent, safe, effective and economical to produce, with broad cross-reactivity against viral variants of public health and veterinary importance. The history of licensed human vaccines reviewed herein demonstrates clearly how the field has evolved to the current state of more passive development and postexposure management. Modern cell culture techniques provide adequate viral substrates for production of representative verified virus seeds. In contrast to outdated nervous tissue-based rabies vaccines, once a suitable substrate is identified, production of high titer virus results in a major qualitative and quantitative difference. Given the current scenario of only inactivated vaccines for humans, highly cell-adapted and stable, attenuated rabies viruses are ideal candidates for consideration to meet the need for seed viruses in the future.
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- 2011
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34. Live attenuated rabies virus co-infected with street rabies virus protects animals against rabies
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Xianfu Wu, Charles E. Rupprecht, Richard Franka, and Heather Henderson
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Rabies ,Vaccines, Attenuated ,medicine.disease_cause ,Injections, Intramuscular ,Virus ,Microbiology ,Mice ,Rabies vaccine ,Cricetinae ,medicine ,Animals ,Duck embryo vaccine ,Mice, Inbred ICR ,Mesocricetus ,General Veterinary ,General Immunology and Microbiology ,business.industry ,Vaccination ,Rabies virus ,Public Health, Environmental and Occupational Health ,medicine.disease ,Survival Analysis ,Virology ,Infectious Diseases ,Rabies Vaccines ,Immunization ,Inactivated vaccine ,Molecular Medicine ,Female ,business ,medicine.drug - Abstract
While current rabies post-exposure prophylaxis (PEP) is highly effective, it is costly and the vaccination regimen is complicated, requiring both inactivated vaccines and immunoglobulins. A one-dose rabies vaccine for human PEP remains a long-term goal. Here, we describe development of a highly attenuated rabies virus ERAg3m, with a mutation in the glycoprotein (G) gene and a switch of the G gene with the matrix protein gene in the viral genome. After a one-dose intramuscular vaccination, the ERAg3m virus protected 100% of mice and hamsters from lethal challenge. In co-infections, using a lethal dose of street rabies virus mixed with ERAg3m, 100% of hamsters and 90% of mice survived and were protected against subsequent infection. A mock co-infection, using inactivated commercial human rabies vaccine and a lethal dose of street rabies virus, protected 100% and 40% of hamsters and mice, respectively. In co-infections, when vaccine was administrated in the left leg and challenge virus in the right leg, the ERAg3m virus protected 40% of mice, while the inactivated vaccine showed no protection. Therefore, live attenuated rabies virus when given pre-exposure or co-infected with street rabies virus, is capable of preventing rabies in two different animal models. Overall, this highly attenuated live rabies virus offered better protection than the inactivated vaccine.
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- 2011
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35. Evolutionary dynamics of rabies viruses highlights the importance of China rabies transmission in Asia
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Ge-Lin Xu, Yongliang Lei, Jianrong Tang, Yan Sun, Charles E. Rupprecht, Jie Wu, Jiaxin Yan, Xiao-Ming Yang, Xianfu Wu, and Sheng-Li Meng
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China ,Time Factors ,Rabies ,Molecular Sequence Data ,Biology ,medicine.disease_cause ,Communicable Diseases, Emerging ,Evolution, Molecular ,Dogs ,N gene ,Phylogenetics ,Virology ,medicine ,Animals ,Cluster Analysis ,Humans ,Rabies transmission ,Evolutionary dynamics ,Lyssavirus ,Phylogeny ,Molecular Epidemiology ,Geography ,Sequence Homology, Amino Acid ,Phylogenetic tree ,Rabies virus ,Sequence Analysis, DNA ,Nucleocapsid Proteins ,medicine.disease ,biology.organism_classification ,Nucleoprotein ,RNA, Viral ,Temporal–spatial dynamic - Abstract
Rabies in Asia is emerging as a serious public health issue. To explore the possible origin, phylogenetic relationships, and evolutionary dynamics of Asian Rabies viruses (RABV), we examined 200 complete nucleoprotein (N) gene sequences from RABV isolates in the region. Phylogeny supported the classification of Asian RABVs into five distinct clusters in lyssavirus genotype 1. Our geospatial and temporal analyses demonstrated that China appears to be the prime source of Asian RABVs. Understanding of rabies transmission and associated human activities, such as dog translocation, can help rabies control and elimination in Asia through collaborative efforts or programs.
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- 2011
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36. Transmission dynamics of rabies in China over the last 40 years: 1969–2009
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Sheng-Li Meng, Jie Wu, Susan A. Nadin-Davis, Ge-Lin Xu, Hong Liu, Xianfu Wu, Guan-Mu Dong, Yongliang Lei, Xiao-Ming Yang, Jiaxin Yan, Charles E. Rupprecht, and Ding-Ming Wang
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China ,Rabies ,Lineage (evolution) ,Molecular Sequence Data ,Biology ,medicine.disease_cause ,Evolution, Molecular ,Viral Envelope Proteins ,Virology ,medicine ,Humans ,Mononegavirales ,Antigens, Viral ,Lyssavirus ,Phylogeny ,Glycoproteins ,Molecular Epidemiology ,Molecular epidemiology ,Rabies virus ,Zoonosis ,Sequence Analysis, DNA ,Rhabdoviridae ,medicine.disease ,biology.organism_classification ,Infectious Diseases - Abstract
Background Rabies is a serious reemerging zoonosis in China. The molecular evolution and transmission patterns of rabies virus inferred from historical data can provide guidelines for better disease control and prevention in the future. Objectives To investigate the epidemiology and evolutionary dynamics of the rabies virus in China. Study design The molecular evolution of 132 viral glycoprotein gene sequences of Chinese rabies viruses collected in 17 provinces and 3 municipalities between 1969 and 2009 was analyzed. Results Phylogenetic analysis revealed that Chinese rabies viruses are subdivided into 6 lineages (A–F) within Lyssavirus genotype 1. Lineage A represents the widely dispersed cosmopolitan lineage while lineage B is closely related to Arctic-like rabies viruses. The remaining lineages (C–F) are typical of those circulating across much of Southeast Asia. The evolutionary rate for Chinese rabies virus was 1.532×10 −4 substitutions per site per year, and the corresponding common ancestor was in about 1115. Conclusions The phylogeographic structure demonstrated Chinese rabies viruses have been transmitted intra-provincially and extra-provincially due to human-related activities.
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- 2010
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37. Enhancing comparative rabies DNA vaccine effectiveness through glycoprotein gene modifications
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Andrew J. Nok, Richard Franka, Michael Niezgoda, Xianfu Wu, Charles E. Rupprecht, Modupe O. V. Osinubi, and A. B. Ogunkoya
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Rabies ,Immunization, Secondary ,Antibodies, Viral ,medicine.disease_cause ,Injections, Intramuscular ,Virus ,DNA vaccination ,Mice ,Viral Envelope Proteins ,Neutralization Tests ,Vaccines, DNA ,medicine ,Virus-neutralizing Antibody ,Animals ,Mononegavirales ,Antigens, Viral ,Lyssavirus ,Glycoproteins ,Mice, Inbred ICR ,General Veterinary ,General Immunology and Microbiology ,biology ,Rabies virus ,Public Health, Environmental and Occupational Health ,Rhabdoviridae ,biology.organism_classification ,Antibodies, Neutralizing ,Virology ,Vaccination ,Infectious Diseases ,Rabies Vaccines ,Mutagenesis, Site-Directed ,Molecular Medicine ,Female - Abstract
Enhancing DNA vaccine effectiveness remains a challenge, especially if the desired goal is immunization efficacy after a single dose. The glycoprotein gene from the rabies virus Evelyn-Rokitnicki-Abelseth (ERA) strain was modified by mutation at amino acid residue 333 from arginine to glutamine. The modified and original unmodified glycoprotein genes were cloned separately and developed as DNA vaccines for immunization in mice. The intramuscular (IM) route using a single dose (100 microg) of a modified DNA vaccine showed virus neutralizing antibody induction by d30, and 80% of the mice survived a challenge in which 100% of unvaccinated controls succumbed. Similar results were obtained using a single dose (10 microg) by the intradermal (ID) route with one-tenth amount of the DNA administered. Administration of single dose of DNA vaccine with unmodified G did not result in the production of detectable levels of virus neutralizing antibody by d30. The results of the IM and the ID routes of administration were statistically significant (P0.01). Based on these preliminary results, a modified glycoprotein gene from the ERA rabies virus strain may be an ideal candidate for DNA vaccine efficacy enhancement.
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- 2009
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38. Development of combined vaccines for rabies and immunocontraception
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Richard Franka, Jan Pohl, Pavel Svoboda, Xianfu Wu, and Charles E. Rupprecht
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endocrine system ,Rabies ,Antibodies, Viral ,medicine.disease_cause ,Virus ,Gonadotropin-Releasing Hormone ,Mice ,Viral Envelope Proteins ,medicine ,Animals ,Vaccines, Contraceptive ,Vaccines, Combined ,Contraception, Immunologic ,Mononegavirales ,Antigens, Viral ,Lyssavirus ,Glycoproteins ,Duck embryo vaccine ,Immunocontraception ,Mice, Inbred ICR ,General Veterinary ,General Immunology and Microbiology ,biology ,Rabies virus ,Public Health, Environmental and Occupational Health ,Rhabdoviridae ,biology.organism_classification ,medicine.disease ,Virology ,Mutagenesis, Insertional ,Infectious Diseases ,Rabies Vaccines ,RNA, Viral ,Molecular Medicine ,Female ,hormones, hormone substitutes, and hormone antagonists - Abstract
Rabies prevention and appropriate population management of free-ranging animals have an important role to play in the eventual elimination of rabies in dogs. An effective sterilant based on rabies vaccines has the potential to create a supportive measure of public acceptability and to reduce associated clinic visit costs. We inserted the coding sequence of gonadotropin-releasing hormone (GnRH) into different locations within the rabies virus ERA glycoprotein (G) gene, and demonstrated that the amino terminus (N), antigenic site IIa, and the junction between the ecto- and cytoplasmic domains (C) of the G were suitable sites for GnRH insertion. The rescued recombinant rabies viruses ERA-N-GnRH and ERA-C-GnRH grew as well as the parental ERA virus, reaching 1x10(9)ffu/ml in cell culture. Insertion and expression of the GnRH were stable in the viruses after multiple passages in vitro. To increase immunogenicity of the GnRH peptide, two copies of GnRH, aligned in tandem, were fused to the N terminus of the G. The recombinant rabies virus ERA-N-2GnRH was recovered and grown to high titers in cell culture. All GnRH-carrying rabies viruses induced antibodies against GnRH in immunized mice and protected 100% of the animals after rabies virus challenge. The recombinant viruses reacted strongly with the serum from a GonaCon-immunized animal. The GnRH-carrying rabies viruses have significant potential in rabies and animal population control.
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- 2009
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39. Rabies virus pathogenesis in relationship to intervention with inactivated and attenuated rabies vaccines
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Wajid Hayat, Xianfu Wu, Andres Velasco-Villa, Lauren Greenberg, Heather Henderson, Charles E. Rupprecht, Dustyn Palmer, Douglas B. Green, Richard Franka, Felix R. Jackson, and Jesse D. Blanton
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Rabies ,medicine.medical_treatment ,Antibodies, Viral ,Vaccines, Attenuated ,medicine.disease_cause ,Virus ,Mice ,Rabies vaccine ,Cricetinae ,medicine ,Animals ,Post-exposure prophylaxis ,Mononegavirales ,Lyssavirus ,Immunization Schedule ,Mice, Inbred ICR ,Mesocricetus ,General Veterinary ,General Immunology and Microbiology ,biology ,Rabies virus ,Public Health, Environmental and Occupational Health ,biology.organism_classification ,medicine.disease ,Macaca mulatta ,Virology ,Vaccination ,Infectious Diseases ,Rabies Vaccines ,Vaccines, Inactivated ,Immunology ,Molecular Medicine ,Female ,medicine.drug - Abstract
Despite progress in vaccine development in the past century the mechanisms behind immune responses elicited by rabies biologics or via natural infection remain largely unknown. In this study, we compared protection elicited by standard, early, or delayed prophylaxis with a reduced number of vaccine doses using inactivated and live-attenuated vaccines. Two-month-old Syrian hamsters, 4-week-old ICR mice or adult rhesus macaques were inoculated with canine rabies virus variants. Thereafter, prophylaxis was initiated 6 h, 1, 2, 3, 4, 5, 6 or 7 days post-exposure (p.e.). One or several doses of inactivated (HDCV), or reverse genetically attenuated (live), or gamma-irradiated (inactivated)-ERAG333 vaccines were administered intramuscularly. The dynamics of virus spread were measured over time in the rodent models. Rabies virus reached the spinal cord at day 4 and brain at day 6 p.e. All hamsters succumbed in groups in which live ERAG333 was delayed until days 5 and 6 p.e. However, 78%, 44%, 56% and 22% of hamsters survived when one dose of live ERAG333 was administered 6 h, 1, 2, 3, and 4 days p.e., respectively. Similarly, 67% survived when inactivated ERAG333 was administered at 24 h p.e. All hamsters succumbed when standard prophylaxis (the Essen regimen) was delayed until days 3–6, but 67% and 33% of hamsters survived when PEP began 1 or 2 days p.e., respectively. Macaques were protected by one dose of attenuated ERAG333 at 24 h p.e. The highly attenuated (live) and inactivated ERAG333 vaccines elicited potent protective immune responses, even when prophylaxis initiation was delayed. When 2–5 doses of commercial vaccine and HRIG were administered according to the Essen scheme, 89–100% of the animals survived. Reduced vaccine schedules provided efficacious intervention, regardless of the total number of vaccine doses administered.
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- 2009
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40. Reemerging Rabies and Lack of Systemic Surveillance in People’s Republic of China
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Yong-Zhen Zhang, Rongliang Hu, Xianfu Wu, Guan-Mu Dong, and Charles E. Rupprecht
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Microbiology (medical) ,China ,Epidemiology ,Rabies ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,lcsh:Medicine ,Disease ,carrier-dog phenomenon ,medicine.disease_cause ,Communicable Diseases, Emerging ,lcsh:Infectious and parasitic diseases ,counterfeit vaccines ,Dogs ,Environmental health ,medicine ,Animals ,Humans ,viruses ,lcsh:RC109-216 ,Dog Diseases ,Seroconversion ,vaccination coverage ,business.industry ,Transmission (medicine) ,Rabies virus ,lcsh:R ,Epidemiologic Surveillance ,medicine.disease ,Virology ,Vaccination ,Infectious Diseases ,mass vaccination campaigns ,Immunization ,Rabies Vaccines ,TheoryofComputation_LOGICSANDMEANINGSOFPROGRAMS ,Population Surveillance ,Perspective ,seroconversion testing ,business ,postexposure prophylaxis - Abstract
Standardized protocols and diagnostic-based surveillance are imperative for detection and elimination., Rabies is a reemerging disease in China. The high incidence of rabies leads to numerous concerns: a potential carrier-dog phenomenon, undocumented transmission of rabies virus from wildlife to dogs, counterfeit vaccines, vaccine mismatching, and seroconversion testing in patients after their completion of postexposure prophylaxis (PEP). These concerns are all scientifically arguable given a modern understanding of rabies. Rabies reemerges periodically in China because of high dog population density and low vaccination coverage in dogs. Mass vaccination campaigns rather than depopulation of dogs should be a long-term goal for rabies control. Seroconversion testing after vaccination is not necessary in either humans or animals. Human PEP should be initiated on the basis of diagnosis of biting animals. Reliable national systemic surveillance of rabies-related human deaths and of animal rabies prevalence is urgently needed. A laboratory diagnosis–based epidemiologic surveillance system can provide substantial information about disease transmission and effective prevention strategies.
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- 2009
41. Are all lyssavirus genes equal for phylogenetic analyses?
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Xianfu Wu, Andres Velasco-Villa, Richard Franka, and Charles E. Rupprecht
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Cancer Research ,Genes, Viral ,Polyadenylation ,Molecular Sequence Data ,Genome, Viral ,medicine.disease_cause ,Genome ,Cell Line ,Viral Proteins ,Intergenic region ,Virology ,medicine ,Animals ,Amino Acid Sequence ,Gene ,Lyssavirus ,Phylogeny ,Genetics ,Base Sequence ,biology ,Phylogenetic tree ,Rabies virus ,biology.organism_classification ,Reverse genetics ,Infectious Diseases ,Sequence Alignment - Abstract
Individual lyssavirus genes were evaluated for phylogenetic studies from available full genome sequences. The full genome of the ERA rabies virus was sequenced and its accuracy was confirmed through virus recovery by reverse genetics. The full length of the ERA is 11,931 nucleotides (nt), with a leader sequence of 58 nt, the nucleoprotein (N) gene of 1350 nt, phosphoprotein (P) gene of 891 nt, matrix protein (M) gene of 606 nt, glycoprotein (G) gene of 1572 nt, RNA-dependent RNA polymerase (L) gene of 6384 nt, Psi-region (or G–L intergenic region) of 400 nt, and a trailer region of 70 nt. The five mono-cistrons are separated by intergenic regions of 2, 5, 5 and 24 nt, respectively. One obvious difference between the ERA and SAD-B19 rabies virus strains was the putative stop/polyadenylation signal of the G gene, with a poly(A 8 ) tract for ERA, and a poly(A 5 ) for SAD-B19. The TGpoly(A 8 ) sequence tract was identified to be a leaky termination signal in the ERA strain. Through analyses of nt diversity, protein co-variations, structural and functional constraints, and reconstruction of phylogenetic trees from comprehensive datasets, we propose lyssavirus genes probably are of similar value for phylogenetic analyses.
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- 2007
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42. Microsporols A-C from the Plant Endophytic Fungus Pestalotiopsis microspore
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Xianfu, Wu, Yadan, Wang, Shuchun, Liu, Xinzhong, Liu, and Liangdong, Guo
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Ascomycota ,Molecular Structure ,Cyclohexanones ,Endophytes ,Spores, Fungal - Abstract
Three new ambuic acid derivatives, microsporols A-C (1-3) and the known compound ambuic acid (4), were isolated from the solid-substrate fermentation cultures of the plant endophytic fungus Pestalotiopsis microspora. Their structures were elucidated primarily by NMR experiments. The absolute configurations of the 6,7-diol moiety in 1 and 2 were assigned using the Snatzke's method, whereas that of 3 was deduced by circular dichroism (CD) exciton chirality method. Compounds 1, 3, and 4 showed moderate 5-lipoxygenase (5-LOX) inhibitory effects.
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- 2015
43. Interactions amongst rabies virus nucleoprotein, phosphoprotein and genomic RNA in virus-infected and transfected cells
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Pinghua Liu, Xianfu Wu, Jun Yang, and Zhen F. Fu
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Messenger RNA ,biology ,RNA-induced transcriptional silencing ,Virus Assembly ,RNA-dependent RNA polymerase ,RNA ,RNA virus ,Phosphoproteins ,Transfection ,biology.organism_classification ,Non-coding RNA ,Virology ,Molecular biology ,Nucleoprotein ,Nucleoproteins ,Rabies virus ,Animals ,RNA, Viral ,RNA, Messenger ,Phosphorylation ,Small nuclear RNA - Abstract
Previous in vitro studies have indicated that rabies virus (RV) phosphoprotein (P), by interacting with the nucleoprotein (N), confers the specificity of genomic RNA encapsidation by N. In this study, interactions amongst N, P and the genomic RNA in virus-infected as well as in transfected cells were studied. The results showed that when N was expressed alone, it bound non-specific RNA, particularly the N mRNA. When N and P were co-expressed, they formed N-P complexes that did not bind to non-specific RNA. When N and P were co-expressed together with (mini-)genomic RNA, N-P complexes preferentially bound the (mini-)genomic RNA. This demonstrated that RV P, by binding to N, does indeed confer specificity of genomic RNA encapsidation by N in vivo. Furthermore, the role of N phosphorylation in the N, P and RNA interactions was investigated. It was found that only N that bound to RNA was phosphorylated, while N in the N-P complex prior to RNA encapsidation was not, suggesting that RV P, by binding to nascent N, prevents the immediate phosphorylation of de novo-synthesized N. However, mutation at the phosphorylation site of N did not alter the pattern of N-P and N-RNA interactions, indicating that N phosphorylation per se does not play a direct role in N-P interaction and RNA encapsidation.
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- 2004
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44. Rabies virus nucleoprotein is phosphorylated by cellular casein kinase II
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Xianfu Wu, Zhen F. Fu, and Xiaojun Lei
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inorganic chemicals ,Cytoplasm ,Biophysics ,macromolecular substances ,Protein Serine-Threonine Kinases ,Biology ,Transfection ,medicine.disease_cause ,environment and public health ,Biochemistry ,Cell Line ,law.invention ,law ,Cricetinae ,Escherichia coli ,medicine ,Animals ,Staurosporine ,Enzyme Inhibitors ,Phosphorylation ,Casein Kinase II ,Nucleocapsid ,Molecular Biology ,Protein kinase C ,Heparin ,Kinase ,Rabies virus ,Cell Biology ,Nucleocapsid Proteins ,Virology ,Molecular biology ,Nucleoprotein ,Kinetics ,enzymes and coenzymes (carbohydrates) ,Nucleoproteins ,Mutation ,Recombinant DNA ,bacteria ,Casein kinase 2 ,Dichlororibofuranosylbenzimidazole ,medicine.drug - Abstract
It has been reported that phosphorylation of rabies virus N plays an important role in the process of viral transcription and replication. Rabies virus N is phosphorylated when expressed alone, indicating that cellular kinase phosphorylates rabies virus N. To identify what cellular kinase phosphorylates rabies virus N, the N was expressed in Escherichia coli and purified by metal affinity chromatography. The recombinant N was phosphorylated by BHK cellular extracts and by purified CK-II. In addition, the phosphorylation of the recombinant N in vitro can be blocked by a CK-II inhibitor, heparin. Furthermore, N phosphorylation in the virus-infected cells can be inhibited by a CK-II specific inhibitor, 5,6-dichloro-beta-D-ribofuranosyl benzimidazole. However, PKC did not phosphorylate the recombinant N in vitro; nor did staurosporine, a PKC and other kinase inhibitor, prevent rabies virus N from phosphorylation. Thus, our data demonstrate that cellular CK-II phosphorylates rabies virus N.
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- 2003
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- View/download PDF
45. Rabies vaccine preserved by vaporization is thermostable and immunogenic
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Marina Siirin, Todd G. Smith, Xianfu Wu, Cathleen A. Hanlon, and Victor Bronshtein
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Time Factors ,medicine.disease_cause ,Vaccines, Attenuated ,Article ,Microbiology ,Mice ,Rabies vaccine ,Antigen ,Drug Stability ,medicine ,Animals ,Humans ,Microbial Viability ,General Veterinary ,General Immunology and Microbiology ,biology ,Immunogenicity ,Rabies virus ,Public Health, Environmental and Occupational Health ,Temperature ,Antigen capture assay ,Viral Load ,Virology ,Titer ,Infectious Diseases ,Rabies Vaccines ,biology.protein ,Molecular Medicine ,Enzootic ,Female ,Antibody ,Volatilization ,medicine.drug - Abstract
A rabies vaccine that is thermostable over a range of ambient environmental temperatures would be highly advantageous, especially for tropical regions with challenging cold-chain storage where canine rabies remains enzootic resulting in preventable human mortality. Live attenuated rabies virus (RABV) strain ERAg333 (R333E) was preserved by vaporization (PBV) in a dry, stable foam. RABV stabilized using this process remains viable for at least 23 months at 22°C, 15 months at 37°C, and 3 hours at 80°C. An antigen capture assay revealed RABV PBV inactivated by irradiation contained similar levels of antigen as a commercial vaccine. Viability and antigen capture testing confirmed that the PBV process stabilized RABV with no significant loss in titer or antigen content. Live attenuated and inactivated RABV PBV both effectively induced RABV neutralizing antibodies and protected mice from peripheral rabies virus challenge. These results demonstrate that PBV is an efficient method for RABV stabilization.
- Published
- 2014
46. Current and future tools for global canine rabies elimination
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Richard Franka, Xianfu Wu, Jessie L. Dyer, Michael Niezgoda, Charles E. Rupprecht, and Todd G. Smith
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medicine.medical_specialty ,Elimination ,Rabies ,Developing country ,Disease ,Education ,Herd immunity ,Dogs ,Virology ,medicine ,Animals ,Humans ,Dog Diseases ,Disease Eradication ,Intensive care medicine ,Disease burden ,Pharmacology ,Prophylaxis ,business.industry ,Prevention ,medicine.disease ,Vaccination ,One Health ,Immunology ,Risk assessment ,business ,Vaccine - Abstract
Even though rabies is almost uniformly fatal, it is readily preventable with currently available tools. Vaccination is highly efficacious for the pre-exposure prophylaxis (PrEP) of rabies in humans and animals, and prompt postexposure prophylaxis (PEP) with vaccine and rabies immune globulin (RIG) can reliably prevent disease in humans. However, access to these tools and knowledge of their proper use are often limited, especially in impoverished, rabies-enzootic countries with the highest disease burden. In the absence of reliable diagnostic capacity and risk assessments, vaccines and RIG are often administered inappropriately, leading to chronic supply shortages and otherwise preventable deaths. Rather than focusing solely on human prophylaxis, it is more cost-effective over the long term to eliminate canine rabies in its natural terrestrial reservoirs. Because more than 99% of human rabies deaths result from dog bites, prevention efforts should focus on dogs. A versatile “One Health” strategy for canine rabies elimination should aim to create sustainable herd immunity in dogs, using proven vaccination strategies at the local level, coupled with community education and humane population management. Such strategies have succeeded in both developed and developing countries, and can be adapted to any locality. Numerous examples in Africa, Asia, and Latin America have shown that community-based, locally guided vaccination and education programs, based on a shared vision and long-term commitment, can eliminate canine rabies. Such programs should have specific goals and measurable outcomes, and should be conducted under the guidance of supportive governments, in collaboration with international partners and nongovernmental organizations. In addition to currently available tools, rabies prevention can be augmented by new dose-sparing human vaccine schedules, alternative routes of vaccine administration, monoclonal antibodies as an alternative to RIG, sensitive and specific point-of-care diagnostics and the development of canine immunocontraceptive methods. Accurate risk assessments of potential human exposures and support for decentralized laboratory capacity will be essential to ensure the most effective utilization of vaccines and RIG until canine rabies has been eliminated.
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- 2013
47. Host–rabies virus protein–protein interactions as druggable antiviral targets
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Xianfu Wu, Vishwanath R. Lingappa, Christine Nichols, M. Dharma Prasad, Vinod Asundi, Andy Atuegbu, Usha F. Lingappa, Debendranath Dey, Michael Corpuz, Shao Feng Yu, Clarence R. Hurt, William Hansen, Alfredo Calayag, Charles E. Rupprecht, Emma Harrell, Hong Shi, Amanda Macieik, James A. Ellison, Jean Francis, Jaisri R. Lingappa, and W. Ian Lipkin
- Subjects
whole pathway screen ,Viral capsid assembly ,viral-host interaction ,Druggability ,medicine.disease_cause ,Drug Discovery ,Chlorocebus aethiops ,protein heterogeneity ,Multidisciplinary ,Drug discovery ,Nucleocapsid Proteins ,drug discovery paradigm ,Infectious Diseases ,Capsid ,PNAS Plus ,5.1 Pharmaceuticals ,Host-Pathogen Interactions ,Development of treatments and therapeutic interventions ,Infection ,Biotechnology ,medicine.drug_class ,Molecular Sequence Data ,Immunology ,Computational biology ,Microbial Sensitivity Tests ,Biology ,Antiviral Agents ,Protein–protein interaction ,Vaccine Related ,Viral Proteins ,Rare Diseases ,assembly intermediate ,Biodefense ,Virology ,medicine ,Animals ,Humans ,Protein Interaction Domains and Motifs ,Amino Acid Sequence ,Vero Cells ,Cell-Free System ,Virus Assembly ,Prevention ,FOS: Clinical medicine ,Rabies virus ,ABCE1 ,Emerging Infectious Diseases ,Orphan Drug ,Good Health and Well Being ,biology.protein ,Antiviral drug - Abstract
We present an unconventional approach to antiviral drug discovery, which is used to identify potent small molecules against rabies virus. First, we conceptualized viral capsid assembly as occurring via a host-catalyzed biochemical pathway, in contrast to the classical view of capsid formation by self-assembly. This suggested opportunities for antiviral intervention by targeting previously unappreciated catalytic host proteins, which were pursued. Second, we hypothesized these host proteins to be components of heterogeneous, labile, and dynamic multi-subunit assembly machines, not easily isolated by specific target protein-focused methods. This suggested the need to identify active compounds before knowing the precise protein target. A cell-free translation-based small molecule screen was established to recreate the hypothesized interactions involving newly synthesized capsid proteins as host assembly machine substrates. Hits from the screen were validated by efficacy against infectious rabies virus in mammalian cell culture. Used as affinity ligands, advanced analogs were shown to bind a set of proteins that effectively reconstituted drug sensitivity in the cell-free screen and included a small but discrete subfraction of cellular ATP-binding cassette family E1 (ABCE1), a host protein previously found essential for HIV capsid formation. Taken together, these studies advance an alternate view of capsid formation (as a host-catalyzed biochemical pathway), a different paradigm for drug discovery (whole pathway screening without knowledge of the target), and suggest the existence of labile assembly machines that can be rendered accessible as next-generation drug targets by the means described.
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- 2013
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48. Development of Genetically Recombinant Rabies Vaccine
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Zafar Ul Ehsan Qureshi, Shahida Afzaal, Zaheer Hussain, Andres Velasco-Villa, Xianfu Wu, and Muhammad Saleem Haider
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education.field_of_study ,business.industry ,Rabies virus ,Population ,medicine.disease ,Recombinant virus ,medicine.disease_cause ,Virology ,Vaccination ,Infectious Diseases ,Rabies vaccine ,Immunology ,medicine ,Rabies ,Vector (molecular biology) ,business ,education ,medicine.drug ,Duck embryo vaccine - Abstract
Purpose: Pakistan is one of the few countries where Rabies is endemic and a great threat to humans as well as live stocks. A large number of individuals died of rabies exposure due to either the limited access to rabies vaccines or the side-effects of sheep brain -originated Sample vaccine. Cell culture-derived rabies vaccines are mostly unaffordable to the needed population under rabies threat. Development of a safer and more affordable vaccine is necessary in Pakistan. Here, we developed two novel recombinant rabies virus vaccines using a local Pakistan rabies virus glycoprotein gene, and tested the efficacy of vaccines in mice. Methods: The glycoprotein gene (RVG) of vector ERAg3p and ERAg3m was substituted, respectively, with a modified Pakistani RVG. The resulting recombinant vectors were applied for reverse genetics to recover two vaccine viruses, PK-SG and PK-DG. The efficacy of PK-SG and PK-DG were tested in mice by intramuscular injection and oral delivery. Results: All mice survived the challenge after intramuscular vaccination using PK-SG, or PK-DG. In the oral vaccination groups, 80% mice with PK-SG and 90% mice with PK-DG survived the challenge. Meanwhile, 80% of the unvaccinated control mice succumbed after challenge. The mean rabies virus neutralizing antibody titers was ≥0.5 IU/ml in all vaccinated groups. Conclusion: Our results demonstrated the efficacy of PK-SG and PK-DG in rabies vaccination in mice. The two recombinant virus strains may be good vaccine candidates for the target animals and humans in Pakistan. Detailed investigations are necessary in the future.
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- 2013
- Full Text
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49. Design of future rabies biologics and antiviral drugs
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Todd G, Smith, Xianfu, Wu, Richard, Franka, and Charles E, Rupprecht
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Biological Products ,Rabies Vaccines ,Rabies ,Rabies virus ,Animals ,Humans ,Antibodies, Viral ,Post-Exposure Prophylaxis ,Antiviral Agents - Abstract
In recent years, no major paradigm shifts have occurred in the utilization of new products for the prevention and control of rabies. Development of new cost-effective rabies biologics and antiviral drugs is critical in continuing to prevent and reduce disease. Current rabies vaccines are highly effective but have developed largely based on technical improvements in the vaccine industry. In the future, alternative approaches for improved vaccines, including novel avirulent rabies virus (RABV) vectors, should be pursued. Any rabies vaccine that is effective without the need for rabies immune globulin (RIG) will contribute fundamentally to disease prevention by reducing the cost and complexity of postexposure prophylaxis (PEP). The lack of high quality, affordable RIG is a continuing problem. Virus-specific monoclonal antibodies (mAbs) will soon fulfill the PEP requirement for passive immunity, currently met with RIG. Several relevant strategies for mAb production, including use of transgenic mice, humanization of mouse mAbs, and generation of human immune libraries, are underway. As a result of successful PEP and pre-exposure prophylaxis in developed countries, until recently, no significant focused efforts have been devoted to RABV-specific antiviral agents. To date, combination therapy including broad spectrum antiviral agents has been successful in only one case, and reports of antiviral activity are often conflicting. Current antiviral strategies target either the nucleoprotein or phosphoprotein, but drugs targeting the viral polymerase should be considered. Considering the lag from creation of new concepts to experimental development and clinical trials, many years will likely elapse between today's ideas and tomorrow's practices.
- Published
- 2011
50. Proteomic profiles of mouse neuro N2a cells infected with variant virulence of rabies viruses
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Chenglong Sun, Dongxia Wang, Xiao-Hu Wang, Ziguo Yuan, Xianfu Wu, Rongliang Hu, Shoufeng Zhang, and Zhuang Ding
- Subjects
Rabies ,Virulence ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Virus ,Cell Line ,Mice ,medicine ,Animals ,Humans ,Electrophoresis, Gel, Two-Dimensional ,Mononegavirales ,Lyssavirus ,Neurons ,biology ,Rabies virus ,General Medicine ,Rhabdoviridae ,biology.organism_classification ,medicine.disease ,Virology ,Gene Expression Regulation ,Cell culture ,Biotechnology - Abstract
We characterized the proteomes of murine N2a cells following infection with three rabies virus (RV) strains, characterized by distinct virulence phenotypes (i.e., virulent BD06, fixed CVS-11, and attenuated SRV9 strains), and identified 35 changes to protein expression using two-dimensional gel electrophoresis in whole-cell lysates. The annotated functions of these proteins are involved in various cytoskeletal, signal transduction, stress response, and metabolic processes. Specifically, a-enolase, prx-4, vimentin, cytokine-induced apoptosis inhibitor 1 (CIAPIN1) and prx-6 were significantly up-regulated, whereas Trx like-1 and galectin-1 were down-regulated following infection of N2a cells with all three rabies virus strains. However, comparing expressions of all 35 proteins affected between BD06-, CVS-11-, and SRV9-infected cells, specific changes in expression were also observed. The up-regulation of vimentin, CIAPIN1, prx-4, and 14-3-3 theta/delta, and downregulation of NDPK-B and HSP-1 with CVS and SRV9 infection were ≥ 2 times greater than with BD06. Meanwhile, Zfp12 protein, splicing factor, and arginine/serine-rich 1 were unaltered in the cells infected with BD06 and CVS- 11, but were up-regulated in the group infected with SRV9. The proteomic alterations described here may suggest that these changes to protein expression correlate with the rabies virus' adaptability and virulence in N2a cells, and hence provides new clues as to the response of N2a host cells to rabies virus infections, and may also aid in uncovering new pathways in these cells that are involved in rabies infections. Further characterization of the functions of the affected proteins may contribute to our understanding of the mechanisms of RV infection and pathogenesis.
- Published
- 2011
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