Search

Restoration of exhausted hepatitis B virus (HBV)-specific CD8+ T cells is one of the important strategies for inhibition of viral replication. The role of interleukin (IL)-33 to recovery of CD8+ T cell activity is not fully elucidated. We investigated the effect of IL-33 on viral-specific CD8+ T cell responses in chronic hepatitis B (CHB) patients in vitro by both phenotypic and functional analysis. Plasma IL-33 was downregulated in CHB patients, while effective antiviral therapy rescued IL-33 expression. There was no significant difference of IL-33 receptor mRNA relative level in CD8+ T cells between CHB patients and controls. IL-33 induced the proliferation of HBV-specific CD8+ T cells, and reduced programmed death-1 expression on HBV-specific CD8+ T cells. IL-33 promoted the direct cytolytic activity of CD8+ T cells against HepG2.2.15 cells through boosting perforin and granzyme B production. Furthermore, IL-33 administration increased HBV-specific CD8+ T cell-mediated HBV replication and HBV antigen secretion mainly via enhancement of interferon-γ and tumor necrosis factor-α. IL-33 reinvigorated antiviral activity of HBV-specific CD8+ T cells, revealing that IL-33 might contribute to viral clearance in persistent HBV infection.

Background: Nonalcoholic steatohepatitis (NASH) is the most severe form of non-alcoholic fatty liver disease (NAFLD) and a potential precursor of hepatocellular carcinoma (HCC). In our previous studies, we found that endocrine fibroblast growth factor 21 (FGF21) played a key role in preventing the development of NASH, however, the FGF15/19 mediated-FGFR4 signaling worsened NASH and even contributed to the NASH-HCC transition. The aim of this study is to determine whether FGF15/FGFR4 signaling could alleviate or aggravate NASH in the FGF21KO mice. Methods: NASH models were established in FGF21KO mice fed with high fat methionine-choline deficient (HFMCD) diet to investigate FGF15/FGFR4 signaling during early stage NASH and advanced stage NASH. Human hepatocytes, HepG2 and Hep3B cells, were cultured with human enterocytes Caco-2 cells to mimic gut-liver circulation to investigate the potential mechanism of NASH development. Results: Significant increase of FGF15 production was found in the liver of the NASH-FGF21KO mice, however the increased FGF15 protein was unable to alleviate hepatic lipid accumulation. In contrast, up-regulated FGF15/19/FGFR4 signaling was found in the FGF21KO mice with increased NASH severity, as evident by hepatocyte injury/repair, fibrosis and potential malignant events. In in vitro studies, blockage of FGFR4 by BLU9931 treatment attenuated the lipid accumulation, up-regulated cyclin D1, and epithelial-mesenchymal transition (EMT) in the hepatocytes. Conclusion: The increased FGF15 in NASH-FGF21KO mice could not substitute for FGF21 to compensate its lipid metabolic benefits thereby to prevent NASH development. Up-regulated FGFR4 signaling in NASH-FGF21KO mice coupled to proliferation and EMT events which were widely accepted to be associated with carcinogenic transformation.

Restoration of exhausted hepatitis B virus (HBV)-specific CD8

The combination of chemotherapy and phototherapy gives rise to a boom in cancer therapy methodology. An all-in-one nanoplatform is of particular interest for increased safety and efficacy geared toward personalized precision medicine. However, low drug loading efficiency, random dispersion and distribution without visualization are widespread concerns. Here, a reactive oxygen species (ROS) responsive drug delivery system for imaging-guided chemo-phototherapy was developed. Polymeric micelles were designed and synthesized using PTX (drug) and Cypate (fluorescence and photosensitizer) as hydrophobic segments and PEG as hydrophilic ones encapsulating PTX. Furthermore, folic acid, as a targeting moiety, was conjugated to PEG for directed drug delivery. We evaluated the ROS-responsive drug release profiles and chemo-phototherapy application in an anticancer therapy. The results suggest these biocompatible amphiphilic polymer conjugates would be promising for applications in imaging-guided chemo-phototherapy.

With inconsistent findings, evidence has been obtained in recent years that metabolic disorders are closely associated with the development of lymphomas. Studies and multiple analyses have been published also indicating that some solid tumor survivors develop a secondary lymphoma, whereas some lymphoma survivors subsequently develop a second malignant neoplasm (SMN), particularly solid tumors. An interaction between the multiple etiologic factors such as genetic factors and late effects of cancer therapy may play an important role contributing to the carcinogenesis in patients with metabolic diseases or with a primary cancer. In this review, we summarize the current knowledge of the multiple etiologic factors for lymphomagenesis, focusing on the SMN in lymphoma, secondary lymphomas in primary cancers, and the lymphomas associated to metabolic disorders/diseases, which have been received less attention previously. Further, we also review the data of coexistence of lymphomas and hepatocellular carcinoma (HCC) in patients with infection of hepatitis C virus and hepatitis B virus. Graphical Abstract

BackgroundPharmacological application of the endocrine fibroblast growth factor15/19 (FGF15/19) and FGF21 holds great promise to be effective therapeutic agents for treating nonalcoholic steatohepatitis (NASH), which is the most severe form of non-alcoholic fatty liver disease (NAFLD) and accepted as a potential precursor of hepatocellular carcinoma (HCC). In our previous studies, we found that FGF21 played a key role in preventing the development of NASH, however, the FGF15/19 mediated-FGFR4 signaling worsened NASH and even contributed to the NASH-HCC transition. MethodsNASH models were established in FGF21KO mice fed with high fat methionine-choline deficient (HFMCD) diet to investigate FGF15/FGFR4 signaling during NASH development. We sought to determine whether FGF15/FGFR4 signaling could alleviate or aggravate NASH in the FGF21KO mice challenged with HFMCD. ResultsSignificant increase of FGF15 production was found in the liver of the NASH-FGF21KO mice, however the increased FGF15 protein was unable to alleviate hepatic lipid accumulation. In contrast, the up-regulated hepatic FGFR4–β‑klotho was found during NASH progression, as evident by hepatocyte injury/repair, fibrosis and potential malignant events, in the NASH-FGF21KO mice. ConclusionThe increased FGF15 production in NASH-FGF21KO mice could not substitute for FGF21 to compensate its lipid metabolic benefits thereby to prevent NASH development. The up-regulated FGFR4/β-klotho was coupled to cellular and molecular events which might associate to carcinogenic transformation.

Tumor necrosis factor-alpha-induced protein 3 (TNFAIP3) is a negative regulator of NF-κB activity. We previously reported that the paired tandem polymorphic dinucleotides TT > A (rs148314165, rs200820567 of TNFAIP3) conferred the risk for systemic lupus erythematosus (SLE) in European and Korean populations. We investigated the genetic association of the TT > A variants, as well as the functional coding variant rs2230926 in exon 3 of TNFAIP3 in 1229 Chinese Han SLE patients and 1608 matched population controls. We further evaluated the role of these variants in regulating expression of the TNFAIP3 gene and NF-κB signaling pathway in their peripheral blood mononuclear cells from Chinese SLE patients. The TT > A variants and the TNFAIP3 exon 3 coding variant rs2230926 demonstrated significant associations in SLE (PTT > A = 8.96 × 10−12, odds ratio [OR] = 2.07, 95% confidence interval [CI] = 1.68–2.55). SLE patients carrying the risk A allele showed reduced messenger RNA expression of the TNFAIP3 gene and increased expression of NF-κB1 in PBMCs. Conditional analyses revealed that the TT > A variants are likely to be causal variants in Chinese Han SLE patients. The TT > A variants associated with Chinese Han SLE and negatively regulate the expression of the TNFAIP3 gene resulting in enhanced NF-κB activity.

Rationale: Hepatocellular carcinoma (HCC) has been increasingly recognized in nonalcoholic steatohepatitis (NASH) patients. Fibroblast growth factor 21 (FGF21) is reported to prevent NASH and delay HCC development. In this study, the effects of FGF21 on NASH progression and NASH-HCC transition and the potential mechanism(s) were investigated. Methods: NASH models and NASH-HCC models were established in FGF21Knockout (KO) mice to evaluate NASH-HCC transition. IL-17A signaling was investigated in the isolated hepatic parenchymal cells, splenocytes, and hepatocyte and HCC cell lines. Results: Lack of FGF21 caused significant up-regulation of the hepatocyte-derived IL-17A via Toll-like receptor 4 (TLR4) and NF-κB signaling. Restoration of FGF21 alleviated the high NAFLD activity score (NAS) and attenuated the TLR4-triggered hepatocyte-IL-17A expression. The HCC nodule number and tumor size were significantly alleviated by treatments of anti-IL-17A antibody. Conclusion: This study revealed a novel anti-inflammatory mechanism of FGF21 via inhibiting the hepatocyte-TLR4-IL-17A signaling in NASH-HCC models. The negative feedback loop on the hepatocyte-TLR4-IL-17A axis could be a potential anti-carcinogenetic mechanism for FGF21 to prevent NASH-HCC transition.

Most cases of hepatitis B virus-associated glomerulonephritis (HBV-GN) occur in children and present with serum HBsAg positivity. Few studies have investigated adult patients with HBV-GN who are serum HBsAg-negative. This study aimed to determine the clinical and pathological features of adult patients with HBV-GN who are serum hepatitis B surface antigen (HBsAg)-negative. Clinical, pathologic, and laboratory findings were collected and analyzed in a cohort of 27 adult patients with HBV-GN who were serum HBsAg-negative upon diagnosis. The study population included mostly men of middle age (40-59 years). Clinically, patients presented with nephrotic syndrome. Serum immunoglobulin G levels were low, whereas serum immunoglobulin M, immunoglobulin A, complement C3 (C3), and complement C4 (C4) levels as well as liver and renal function tests were normal in most or all patients. Among the 27 patients, 21 tested positive for HBV antibodies. Membranous nephropathy was the dominant pathological form on kidney biopsy. In addition, only a few patients showed a "full house" staining pattern and renal immune deposit of complement C1q (C1q). Serum HBsAg-negative HBV-GN may represent a late stage of HBV infection. We recommend routine testing for HBV markers on renal biopsy in regions where HBV is prevalent, even when tests for serum HBV markers are negative.

Previously published work has demonstrated that combining gemcitabine with irreversible electroporation (IRE) results in increased drug delivery to pancreatic adenocarcinoma cells in vivo. This study assessed the efficacy of IRE + gemcitabine and IRE + FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan, and oxaliplatin), the impact of the superior regimen on survival, and the safety of electrochemotherapy in human subjects. Histologic analysis was performed after in vitro and in vivo treatment of S2013 and Panc-1 pancreatic cancer cells and S2013 orthotopic tumors, respectively, and levels of apoptotic machinery and cell cycle proteins were evaluated using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot. Electrochemotherapy (ECT) with IRE and FOLFIRINOX resulted in increased tumor cells apoptosis compared with gemcitabine, gemcitabine + IRE, and FOLFIRINOX alone, and significantly improved overall survival when compared with mice treated with IRE or FOLFIRINOX. Increased tumor cell apoptosis, caspase-3 mRNA, active caspase-3 protein, and decreased cell proliferation were noted at the time of death or euthanasia in the ECT group compared with folinic acid alone. In five patients, ECT with either FOLFIRINOX or gemcitabine was well-tolerated and resulted in no dose-limiting toxicities. ECT thus results in synergistic antitumor activity compared with either treatment modality used alone, resulting in increased tumor cell apoptosis as well as decreased tumor cell proliferation and improved overall survival. Pilot data suggest that ECT represents a promising modality for the treatment of patients with locally advanced pancreatic cancer. The human subject portion of this work was conducted as part of an investigator-initiated clinical trial at the University of Louisville (NCT03484299).

Background: Non-alcoholic fatty liver disease(NAFLD) encompasses a broad spectrum of disorders, ranging from non-progressive bland steatosis to non-alcoholic hepatitis (NASH), cirrhosis, and malignant transformation into hepatocellular carcinoma (HCC). Accumulating evidence indicates that lipid metabolic reprogramming mediates the transition from NASH to HCC, however the NASH related carcinogenesis and role of FGF21 played during NASH-HCC transition are largely unknown. while fibroblast growth factor 21 (FGF21) exerts a key role in lipid homeostasis and play a promising therapeutic candidate for the treatment of obesity and diabetes. Aim: To investigate the effect of FGF21 on lipid metabolic reprogramming during the NASH-HCC carcinogenetic transformation and to reveal the potential NASH-HCC mechanism. Methods: Three NASH-HCC transition models were established in FGF21 knockout (KO) mice, with treatment of DEN at aged 2 weeks at 40 mg/kg body weight (i.p.) and feeding, 1) high fat diet (HFD, 60% kcal% fat); 2) western-style high fat diet (WSHFD, 60% kcal% fat and 19% kcal% fructose); and 3) methionine/choline-deficient diet (MCD). The cellular and molecular events, in turn, de novo lipogenesis, sphingolipid metabolism, white adipose tissue (WAT) lipolysis, insulin resistance (IR), release of free fatty acids (FFAs), metabolites of gut flora, carcinogenesis signaling pathways and NASH-HCC initiation, were determined both in vivo and in vitro. The in vitro studies were performed using shRNA-FGF21 knock down hepatocyte and HCC cell lines. Results: Aberrant lipid components, gut microbiome, hepatic Hippo-YAP and NF-kB signaling were found consistently in the NASH-HCC tissues from FGF21-KO mice with 3 diets treatments, compared to the wild type controls. Increased de novo lipogenesis, FFAs overflow to the liver, and inflammation agents from the metabolites of gut flora upregulated the hepatic sphingosine Kinase 1 (SPHK1) expression and its product sphingosine-1-phosphate (S1P), subsequently induced YAP dephosphorylation and nuclear localization. rhFGF21 or SPHK1 inhibitor (SKI-II) treatment significantly decreased the tumor volumes via alleviation of FFAs and S1P productions. Use of curcumin to modulate gut microbiota resulted in suppression of NASH-HCC growth in mice. Conclusion: 1) lack of FGF21 played a key role in hepatic lipid metabolism disorder in liver; 2) lack of FGF21 accelerated the SPHK1-S1P-HIPPO signaling promoted NASH-HCC transition; 3) administration of rhFGF21 not only attenuates NASH, but also prevents HCC carcinogenetic transformation via down-regulation of the SPHK1-S1P-HIPPO axis. This work was supported by an Institutional Development Award (IDeA) from the NIGMS of the National Institutes of Health under grant number P20GM113226. Key Words: Fibroblast growth factor 21; Steatohepatities; Hepatocellular carcinoma; Free fatty acid; Sphingolipid Citation Format: Xiaoju Shi, Robert C. Martin, Youxi Yu, Yujia Chen, Xingtong Wang, Guangyi Wang, Guoyue Lv, Ping Zhang, Yan Li. Lack of FGF21 accelerates NASH-HCC transition via up-regulation of hepatic SPHK1-S1P-HIPPO signaling in murine models [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2550.

Ischemic preconditioning (IPC) and remote ischemic perconditioning (RIPer) confer protective effects against liver ischemia-reperfusion injury (IRI), but data about RIPer applying in liver transplantation is lacking. The study aimed to evaluate whether the combination of IPC and RIPer provides reinforced protective effects. C57BL/6 mice (160 pairs) were allocated into four groups: control, subjected to liver transplantation only; IPC, donor hilar was clamped for 10 min followed by 15 min of reperfusion; RIPer, three cycles of occlusion (5 min) and opening (5 min) of femoral vascular bundle were performed before reperfusion; IPC + RIPer, donors and recipients were subjected to IPC and RIPer respectively. Liver tissues were obtained for histological evaluation, TUNEL staining, malondialdehyde assays, GSH-Px assays, and NF-κB p65 protein and Bcl-2/Bax mRNA analyses. Blood samples were used to evaluate ALT, AST, TNF-α, NOx levels and flow cytometry. We found that protective efficacy of RIPer is less than IPC in terms of ALT, TNF-α, GSH-Px and NOx at 2 h postoperation, but almost equivalent at 24 h and 72 h postoperation. Except for Suzuki scores, ALT, Bcl-2/Bax mRNA ratio, other indices showed that combined treatment brought enhanced attenuation in IRI, compared with single treatment, through additive effects on antioxidation, anti-apoptosis, modulation of microcirculation disturbance, and inhibition of innate immune response. This study suggested a combined strategy that could enhance protection against IRI in clinical liver transplantation, otherwise, provided a hint that RIPer’s mechanism might be partly or totally different from IPC in humoral pathway.

Hepatitis B virus (HBV) has been suspected to contribute to several autoimmune diseases, including Sjögren's syndrome (SS), although the exact mechanism is unknown. The 2'-5' oligoadenylate synthetase (OAS1) is one of the most important components of the immune system and has significant antiviral functions. We studied a polymorphism rs10774671 of OAS1 gene in Han Chinese descent. The minor allele G was significantly associated with a decreased risk for SS, anti-SSA-positive SS, and anti-SSA-positive SS complicated with HBV infection, which have not been seen in anti-SSA-negative SS and HBcAb-negative SS patients. Gene expression analysis showed that the risk-conferring A allele was correlated with lower expression of p46 and increased expression of p42, p48, and p44. A functional study of enzymatic activities revealed that the p42, p44, and p48 isoforms display a reduced capacity to inhibit HBV replication in HepG2 cells compared to the normal p46 isoform. Our data demonstrated that the functional variant, rs10774671, is associated with HBV infection and anti-SSA antibody-positive SS. The SAS variant switches the primary p46 isoform to three alternatives with decreased capacities to inhibit HBV replication. These data indicated that individuals harboring the risk allele might be susceptible to hepatitis B infection and SS development.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a novel approach for performing liver resection, and the number of clinical applications of this technique has rapidly increased within recent years. ALPPS is important in patients who have insufficient residual liver volume and cannot undergo radical hepatic resection. The most common postoperative complications of ALPPS include biliary fistula and infection. To date, postoperative acute kidney injury following ALPPS has not been reported. The current study reports the case of a 63-year-old patient with hepatitis B-induced cirrhosis who underwent the first stage of ALPPS without completion of the second step. The patient developed postoperative acute kidney injury following ALPPS. The present case study suggests that the use of ALPPS in patients at risk of chronic renal damage should be approached with caution in order to avoid postoperative acute kidney injury. Furthermore, improvements in surgical techniques and skills of the surgeons performing the procedure are required to reduce the surgery duration and improve patient outcomes.

Hepatitis B virus (HBV) has been suspected to contribute to several autoimmune diseases, including Sjögren’s syndrome (SS), although the exact mechanism is unknown. The 2′–5′ oligoadenylate synthetase (OAS1) is one of the most important components of the immune system and has significant antiviral functions. We studied a polymorphism rs10774671 of OAS1 gene in Han Chinese descent. The minor allele G was significantly associated with a decreased risk for SS, anti-SSA-positive SS, and anti-SSA-positive SS complicated with HBV infection, which have not been seen in anti-SSA-negative SS and HBcAb-negative SS patients. Gene expression analysis showed that the risk-conferring A allele was correlated with lower expression of p46 and increased expression of p42, p48, and p44. A functional study of enzymatic activities revealed that the p42, p44, and p48 isoforms display a reduced capacity to inhibit HBV replication in HepG2 cells compared to the normal p46 isoform. Our data demonstrated that the functional variant, rs10774671, is associated with HBV infection and anti-SSA antibody-positive SS. The SAS variant switches the primary p46 isoform to three alternatives with decreased capacities to inhibit HBV replication. These data indicated that individuals harboring the risk allele might be susceptible to hepatitis B infection and SS development.

Background: Nonalcoholic steatohepatitis (NASH) is the most severe form of non-alcoholic fatty liver disease (NAFLD) and a potential precursor of hepatocellular carcinoma (HCC). FGF21, with its metabolic benefits, was reported as the liver safeguard to protect from obesity, diabetes, and NAFLD. Recent study showed an exosome based FGF21 inhibition via organs communication to regulate hepatic metabolism. However, the role of the exosome-FGF21 axis in NASH-HCC has never been studied. Aim: To study the exosome based FGF21 metabolic regulation during NASH-HCC carcinogenetic transformation. Methods: NASH-HCC model was induced in FGF21 knockout (KO) mice and wild type (WT) control using methionine-choline-deficient diets (MCD) and diethylnitrosamine (DEN). The exosomes releasing, miRNA and protein contents were analyzed in the primary cultured hepatocytes from the liver tissues of NASH-HCC mice (KO and WT) as well as benign controls. FGF21 was knockdown (KD) by shRNA in a mouse hepatoma cell line (Hepa1-6) and a benign mouse hepatocyte cell line (FL83B) to investigate the potential carcinogenetic signaling related to exosome-FGF21 axis. Result: NASH-HCC model was successfully established with confirmation of the metabolic disorders and liver cancer development. Early HCC detection and increased HCC incidence were found in the KO-MCD mice (P Conclusion: lack of FGF21 plays critical role for the exosome retention in hepatocytes of NASH mice but not in HCC mice. Abnormal traffic of exosomes contribute to the carcinogenetic signaling. This work was supported by an Institutional Development Award (IDeA) from the NIGMS of the National Institutes of Health under grant number P20GM113226. Citation Format: Youxi Yu, Robert C. Martin, Qianqian Zheng, Xiaoju Shi, Xingkai Liu, Wei Guo, Suping Li, Ping Zhang, Yan Li. Lack of FGF21 promotes NASH-HCC transition via exosome-mediated carcinogenetic signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4373.

The rag locus of Porphyromonas gingivalis encodes a putative TonB-dependent outer membrane receptor, RagA, and a 55-kDa immunodominant antigen, RagB. Inactivation of either ragA or ragB prevented expression of both RagA and RagB. Both the ragA and ragB mutants were significantly less virulent than wild-type strains in a murine model of infection.

The chemokine receptors CXCR4 and CCR5 are required for HIV-1 to enter cells, and the progression of HIV-1 infection to AIDS involves a switch in the co-receptor usage of the virus from CCR5 to CXCR4. These receptors therefore make attractive candidates for therapeutic intervention, and we have investigated the silencing of their genes by using ribozymes and single-stranded antisense RNAs. In the present study, we demonstrate using ribozymes that a depletion of CXCR4 and CCR5 mRNAs can be achieved simultaneously in human PBMCs (peripheral blood mononuclear cells), cells commonly used by the virus for infection and replication. Ribozyme activity leads to an inhibition of the cell-surface expression of both CCR5 and CXCR4, resulting in a significant inhibition of HIV-1 replication when PBMCs are challenged with the virus. In addition, we show that small single-stranded antisense RNAs can also be used to silence CCR5 and CXCR4 genes when delivered to PBMCs. This silencing is caused by selective degradation of receptor mRNAs.

Background and objective: Polycystic liver disease (PCLD) represents a group of genetic disorders that include autosomal dominant polycystic kidney disease (ADPKD) and isolated polycystic liver disease (iPCLD). There is currently no definitive treatment except for liver transplantation. The aim of this study was to assess the expression level of aquaporin 1 (AQP1) on the PCLD cysts with different sizes and provide the potential therapeutic target. Methods: We collected 3 normal bile ducts, and recruited 8 patients with simple liver cyst disease, 24 patients with ADPKD, and 17 patients with iPCLD. AQP1 expression in different types of cyst walls and in normal bile ducts was detected using real time quantitative PCR, western blot and immunofluorescence staining. We also compared AQP1 expression levels in cysts of different sizes. Besides, ionic concentrations, pH and osmolality of cyst fluid were analyzed. Results: The results showed that AQP1 expression in PCLD cysts was significantly higher than that in simple liver cysts and the normal bile ducts. In addition, a comparable increasing trend was found in cysts of smaller sizes to cysts of larger sizes. pH values, the sodium and chloride concentrations were higher in cyst fluid than that in the serum. Conclusions: AQP1 was overexpressed in cystic cholangiocytes. A tendency of increased AQP1 protein expression in correlation with the cyst size was also found. These observations offered a direction into the molecular mechanisms of cyst expansion and maybe provide new treatment strategies to reduce fluid secretion into liver cysts.

The effect of Bordetella bronchiseptica infection on the viability of murine macrophage-like cells and on primary porcine alveolar macrophages was investigated. The bacterium was shown to be cytotoxic for both cell types, particularly where tight cell-to-cell contacts were established. In addition, bvg mutants were poorly cytotoxic for the eukaryotic cells, while a prn mutant was significantly less toxic than wild-type bacteria. B. bronchiseptica -mediated cytotoxicity was inhibited in the presence of cytochalasin D or cycloheximide, an inhibitor of microfilament-dependent phagocytosis or de novo eukaryotic protein synthesis, respectively. The mechanism of eukaryotic cell death was examined, and cell death was found to occur primarily through a necrotic pathway, although a small proportion of the population underwent apoptosis.

The outer membrane protein RagB is one of the major virulence factors of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis). In order to induce protective immune response against P. gingivalis infection, an mGITRL gene-linked ragB DNA vaccine (pIRES-ragB-mGITRL ) was constructed. Six-week-old female BALB/c mice were immunized with pIRES-ragB-mGITRL through intramuscular injection and then challenged by subcutaneous injection in the abdomen with P. gingivalis. RagB-specific antibody-forming cells were evaluated by an Enzyme-linked immunosorbent spot, and specific antibody was determined by enzyme-linked immunosorbent assay. In addition, the frequencies of Tfh and IFN-γ(+) T cells in spleen were measured using flow cytometer, and the levels of IL-21 and IFN-γ mRNA or proteins were detected by real time RT-PCR or ELISA. The data showed that the mGITRL-linked ragB DNA vaccine induced higher levels of RagB-specific IgG in serum and RagB-specific antibody-forming cells in spleen. The frequencies of Tfh and IFN-γ(+) T cells were obviously expanded in mice immunized by pIRES-ragB-mGITRL compared with other groups (pIRES or pIRES-ragB ). The levels of Tfh and IFN-γ(+) T cells associated cytokines were also significantly increased in pIRES-ragB-mGITRL group. Therefore, the mice immunized with ragB plus mGITRL showed the stronger resistant to P. gingivalis infection and a significant reduction of the lesion size caused by P. gingivalis infection comparing with other groups. Taken together, our findings demonstrated that intramuscular injection of DNA vaccine ragB together with mGITRL induced protective immune response dramatically by increasing Tfh and IFN-γ(+) T cells and antibody production to P. gingivalis.

Optical orthogonal codes (OOCs) have been applied in OCDMA system because of their good correlation properties, especially the (n,w,1) optimal optical orthogonal codes. In this paper, based on block design and O-plus theory, the relationship between optimal optical orthogonal codes and O-plus Matrix is presented. One method, which could construct strict-optimal optical orthogonal codes, is proposed based on O-plus Matrix. It has high simulation efficiency, saves the code length and has the maximum capacity of Johnson Bound. Besides, the good correlation properties of codewords prove the validity of this method.

A new type of address code-Optical Orthogonal Code Pairs (OOCP) for Optical Code Division Multiple Access (OCDMA) system is presented in this paper according to the theory of sequence pair. Simultaneously, the concept of OOCP and correlation are defined, and OOCPs of capacity 1 are obtained by using exhaustive algorithm. Finally, OOCPs of larger capacity can be obtained by the recursive construction method.

The rag locus of Porphyromonas gingivalis W50 encodes RagA, a predicted tonB -dependent receptor protein, and RagB, a lipoprotein that constitutes an immunodominant outer membrane antigen. The low G+C content of the locus, an association with mobility elements, and an apparent restricted distribution in the species suggested that the locus had arisen by horizontal gene transfer. In the present study, we have demonstrated that there are four divergent alleles of the rag locus. The original rag allele found in W50 was renamed rag-1 , while three novel alleles, rag-2 to rag-4 , were found in isolates lacking rag-1 . The three novel alleles encoded variants of RagA with 63 to 71% amino acid identity to RagA1 and each other and variants of RagB with 43 to 56% amino acid identity. The RagA/B proteins have homology to numerous Bacteroides proteins, including SusC/D, implicated in polysaccharide uptake. Monoclonal and polyclonal antibodies raised against RagB1 of P. gingivalis W50 did not cross-react with proteins from isolates carrying different alleles. In a laboratory collection of 168 isolates, 26% carried rag-1 , 36% carried rag-2 , 25% carried rag-3 , and 14% carried rag-4 (including the type strain, ATCC 33277). Restriction profiles of the locus in different isolates demonstrated polymorphism within each allele, some of which is accounted for by the presence or absence of insertion sequence elements. By reference to a previously published study on virulence in a mouse model (M. L. Laine and A. J. van Winkelhoff, Oral Microbiol. Immunol. 13: 322-325, 1998), isolates that caused serious disease in mice were significantly more likely to carry rag-1 than other rag alleles.