Search

Mumps virus (MuV) is highly neurotropic and neurovirulent, hence, the neurovirulence of virus seeds used in the production of mumps vaccines must be tested. The previous neurovirulence evaluation method involves measuring the area of the cavity in the Lewis neonatal rat brain caused by MuV through paraffin sectioning and hematoxylin-eosin (HE) staining. However, the processes of paraffin sectioning and HE staining are time consuming and complicated. To solve this problem, in this study, a vibratome sectioning system was first deployed to evaluate MuV neurovirulence in the rat brain instead of paraffin sectioning and HE staining. The results showed that the vibratome sectioning method could assess the neurovirulence potential of MuV more objectively and efficiently. In addition, the effects of different MuV doses and the ages of the rats in days on this evaluation method were explored. The results indicate that MuV at no less than 10 50 % cell culture infective dose (CCID

The coronavirus disease 2019 (COVID-19) broke out in early December 2019 in Wuhan, China and escalated into a global pandemic. There is an urgent need to understand the biology of SARS-CoV-2. In this letter, we report the isolation and characterization of seven isolates of SARS-CoV-2. Results show that our viruses have 99% sequence identity with published virus sequences. In addition, all viruses grew well in Vero cells, and one of the viruses had a deletion mutation after short passage. These results shall facilitate the understanding of the characteristics of SARS-CoV-2 in vitro.

Rabies, caused by rabies virus (RABV), is a fatal zoonosis, which still poses a threat to public health in most parts of the world. Glycoprotein of RABV is the only viral surface protein, which is critical for the induction of virus-neutralizing antibodies (VNA). In order to improve the production of VNA, recombinant RABVs containing two copies of G gene and codon-optimized G gene were constructed by using reverse genetics, named LBNSE-dG and LBNSE-dOG, respectively. After being inoculated into the mouse brains, LBNSE-dOG induced more apoptosis and recruited more inflammatory cells than LBNSE-dG and LBNSE, resulting in reduced virulence in vivo. After intramuscular (im) immunization in mice, LBNSE-dOG promoted the formation of germinal centres (GCs), the recruitment of GC B cells and the generation of antibody-secreting cells (ASCs) in the draining lymph nodes (LNs). Consistently, LBNSE-dOG boosted the production of VNA and provided better protection against lethal RABV challenge than LBNSE-dG and LBNSE when it was used as both live and inactivated vaccines. Our results demonstrate that the codon-optimized RABV LBNSE-dOG displays attenuated pathogenicity and enhanced immunogenicity, therefore it could be a potential candidate for the next generation of rabies vaccines.

Carbone KM, Wolinsky JS (2001) Mumps Virus. In: Fields BN, Howley PM, Griffin DE, Lamb RA, Martin MA, Roizman B, Straus SE, Knipe DM (eds) Fields-virology, vol 4. pp 1381–1400 Carr MJ, Moss E, Waters A, Dean J, Jin L, Coughlan S, Connell J, Hall WW, Hassan J (2010) Molecular epidemiological evaluation of the recent resurgence in mumps virus infections in Ireland. J Clin Microbiol 48:3288–3294 Article Google Scholar Cui A, Zhu Z, Chen M, Zheng H, Liu L, Wang Y, Ma Y, Wang C, Fang X, Li P, Guan R, Wang S, Zhou J, Zheng L, Gao H, Ding Z, Li L, Bo F, Sun Z, Zhang Z, Feng D, He J, Chen H, Jin L, Rota PA, Xu W (2014) Epidemiologic and genetic characteristics of mumps viruses isolated in China from 1995 to 2010. Infect Genet Evol 21:384–390 Article Google Scholar Cui A, Zhu Z, Hu Y, Deng X, Sun Z, Zhang Y, Mao N, Xu S, Fang X, Gao H, Si Y, Lei Y, Zheng H, He J, Wu H, Xu W (2017) Mumps epidemiology and mumps virus genotypes circulating in mainland China during 2013–2015. PLoS ONE 12:e0169561 Article Google Scholar Cui A, Zhu Z, Zhang Y, Qiu Q, Mao N, XU S, Ji Y, Wang H, Xu W (2018) Viral surveillance and genetic characteristics of mumps viruses in China during 2001–2017. Chin J Vacc Immun 24:249–255 Google Scholar Dayan GH, Rubin S (2008) Mumps outbreaks in vaccinated populations: are available mumps vaccines effective enough to prevent outbreaks? Clin Infect Dis 47:1458–1467 Article Google Scholar Iabs (2006) IABs scientific workshop on neurovirulence tests for live virus vaccines, January 31-February 1, 2005, Geneva. Biologicals 34:233–236 Article Google Scholar Park SH (2015) Resurgence of mumps in Korea. Infect Chemother 47:1–11 Article Google Scholar Rubin SA, Afzal MA (2011) Neurovirulence safety testing of mumps vaccines–historical perspective and current status. Vaccine 29:2850–2855 CAS Article Google Scholar Rubin SA, Pletnikov M, Carbone KM (1998) Comparison of the neurovirulence of a vaccine and a wild-type mumps virus strain in the developing rat brain. J Virol 72:8037–8042 CAS Article Google Scholar Rubin SA, Pletnikov M, Taffs R, Snoy PJ, Kobasa D, Brown EG, Wright KE, Carbone KM (2000) Evaluation of a neonatal rat model for prediction of mumps virus neurovirulence in humans. J Virol 74:5382–5384 CAS Article Google Scholar Sauder CJ, Vandenburgh KM, Iskow RC, Malik T, Carbone KM, Rubin SA (2006) Changes in mumps virus neurovirulence phenotype associated with quasispecies heterogeneity. Virology 350:48–57 CAS Article Google Scholar Turner PC, Forsey T, Minor PD (1991) Comparison of the nucleotide sequence of the SH gene and flanking regions of mumps vaccine virus (Urabe strain) grown on different substrates and isolated from vaccinees. J Gen Virol 72(Pt 2):435–437 CAS Article Google Scholar WHO (2012) Weekly epidemiological record releve epidemiologique hebdomadaire 29:241–248 Google Scholar Xu P, Luthra P, Li Z, Fuentes S, D’Andrea JA, Wu J, Rubin S, Rota PA, He B (2012) The V protein of mumps virus plays a critical role in pathogenesis. J Virol 86:1768–1776 CAS Article Google Scholar Zengel J, Phan SI, Pickar A, Xu P, He B (2017) Immunogenicity of mumps virus vaccine candidates matching circulating genotypes in the United States and China. Vaccine 35:3988–3994 CAS Article Google Scholar Download references This work was partially supported by the National Natural Science Foundation of China (31702248), the Beijing Innovation Fund for Small Technology-based Firms (Z16010101394), We gratefully acknowledge the mumps throat swab samples support from Center for Zhejiang Provincial center For Disease Control and Prevention, Jiangsu Provincial Center For Disease Control And Prevention, Shanxi Provincial Center For Disease Control And Prevention, Beijing Center For Diseases Prevention And Control and Hubei Provincial Center For Disease Control And Prevention. Yajing Zhang and Lixia Xie contributed equally to the study. R&D Department, Shanghai King-cell biotechnology Co., Ltd., Shanghai, 201506, China Yajing Zhang, Lixia Xie, Juncheng Ruan, Yulin Gu, Biao Niu, Yachun Zhang, Qi An & Dayong Tian State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China Benjie Chai, Zhenfang Fu & Dayong Tian You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar You can also search for this author in PubMed Google Scholar Correspondence to Zhenfang Fu or Qi An or Dayong Tian. The authors declare that they have no conflict of interest. Animal experiments in this study were approved by the Ethics Committees of Huazhong Agriculture University (Approval Number: HZAUMO-2019-020). Below is the link to the electronic supplementary material. Reprints and Permissions Zhang, Y., Xie, L., Chai, B. et al. A Highly Attenuated Mumps Virus Strain of Genotype F Generated by Passaging in Vero Cells. Virol. Sin. (2020). https://doi.org/10.1007/s12250-020-00292-5 Download citation Received: 24 February 2020 Accepted: 28 June 2020 Published: 29 September 2020 DOI: https://doi.org/10.1007/s12250-020-00292-5

Eliminating rabies is challenging in many developing countries, especially in rural areas. In contrast to the annual decline of human cases in China in last decade, the incidence of rabies in livestock has been increasingly reported. This paper reports the rabies outbreaks in beef cattle (Angus) in Shaanxi Province, China, which caused 31 and 5 deaths at an attack rate of 19.4% (95% CI: 13.6%-26.4%) and 0.25% (95% CI: 0.1%-0.6%) in a satellite cow farm (farm A) and a core intensive farm (farm B), respectively. The rabies infection was confirmed by several laboratory tests, and rabies virus (RABV) strains SXBJ15 and SXYL15 were isolated and characterized from farm A and B, respectively. The two strains were found to have a high genomic sequence similarity to the dog-associated China clade I strains previously identified in the neighbouring area. SXBJ15 was shown to have a higher mouse pathogenicity (1.07) than SXYL15 (0.45). RABV was also detected in the saliva and salivary glands from the affected cattle. The potential causes were investigated on the farm, and the biosecurity scores were 20 and 64 (a full score of 82) for farms A and B, respectively. The rabies infection is likely to result from rabid free-roaming dogs (FRDs). On farm A with more cow deaths, the rabies transmission between animals can be attributed to the improper disposal of aborted foetuses and placental materials as a food source for rabid FRDs, high stocking density and drinking water sharing. Additionally, vaccinating cattle with a canine vaccine was shown to help stop the spread of rabies in herds. These results indicate that the occurrence of RABV on cattle farms can be prevented by improving biosecurity measures to control the entry of rural FRDs on the farm and immunizing farm cattle against rabies.

Rabies is one of the most dangerous and widespread zoonosis and is characterized by severe neurological signs and a high case-mortality rate of nearly 100%. Vaccination is the most effective way to prevent rabies in humans and animals. In this study, the relationship between exhaustive exercise and the humoral immune response after immunization with inactivated rabies vaccine was investigated in a mouse model with one-time exhaustive exercise. It was found that compared with the mice with no exercise after vaccination, no significant differences were found in those with exhaustive exercise after vaccination on body-weight changes, virus-neutralizing antibody (VNA) titers, antibody subtypes and survivor ratio after lethal rabies virus (RABV) challenge. This study indicated that exhaustive exercise does not reduce the effects of the rabies inactivated vaccine.

// Ming Zhou 1,* , Lei Wang 1,* , Songqin Zhou 1,* , Zhao Wang 1 , Juncheng Ruan 1 , Lijun Tang 3 , Ziming Jia 3 , Min Cui 1 , Ling Zhao 1 and Zhen F. Fu 1,2 1 State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China 2 Department of Pathology, University of Georgia, Athens, GA, USA 3 Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Academy of Preventive Medicine, Wuhan, China * These authors have contributed equally to this paper Correspondence to: Ling Zhao, email: // Zhen F. Fu, email: // Keywords : rabies, recombinant rabies virus, GM-CSF, oral vaccine, dog, Immunology and Microbiology Section, Immune response, Immunity Received : July 12, 2015 Accepted : August 26, 2015 Published : September 30, 2015 Abstract Developing efficacious oral rabies vaccines is an important step to increase immunization coverage for stray dogs, which are not accessible for parenteral vaccination. Our previous studies have demonstrated that recombinant rabies virus (RABV) expressing cytokines/chemokines induces robust protective immune responses after oral immunization in mice by recruiting and activating dendritic cells (DCs) and B cells. To develop an effective oral rabies vaccine for dogs, a recombinant attenuated RABV expressing dog GM-CSF, designated as LBNSE-dGM-CSF was constructed and used for oral vaccination in a dog model. Significantly more DCs or B cells were activated in the peripheral blood of dogs vaccinated orally with LBNSE-dGM-CSF than those vaccinated with the parent virus LBNSE, particularly at 3 days post immunization (dpi). As a result, significantly higher levels of virus neutralizing antibodies (VNAs) were detected in dogs immunized with LBNSE-dGM-CSF than with the parent virus. All the immunized dogs were protected against a lethal challenge with 4500 MICLD 50 of wild-type RABV SXTYD01. LBNSE-dGM-CSF was found to replicate mainly in the tonsils after oral vaccination as detected by nested RT-PCR and immunohistochemistry. Taken together, our results indicate that LBNSE-dGM-CSF could be a promising oral rabies vaccine candidate for dogs.