Canine Distemper Virus Utilizes Different Receptors to Infect Chicken Embryo Fibroblasts and Vero cells / 中国病毒学·英文版

Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts(CEF)is a common method to develop attenuated live vaccines with full security.Canine distemper virus(CDV)also does this,but the mechanisms and particular receptors remain unclear.Virus overlay protein blot assays were carried out on CEF membrane proteins,which were extracted respectively with a Mem-PERTM kit,a radioimmunoprecipitation assay buffer or a modified co-immunoprecipitation method,and revealed a common 57 kDa positive band that differed from the 42-kDa positive band in Vero cells and also from those receptors reported in lymphocytes and293 cells,indicating a receptor diversity of CDV and the possibility of the 57-kDa protein acting as a receptor that is involved in adaptive infection of CDV Kunming strain to CEF.

Integrin Activation and Viral Infection / 中国病毒学·英文版

Integrins are members of a ubiquitous membrane receptor family which includes 18 different α subunits and 8 β subunits forming more than 20 α/β heterodimers. Integrins play key functions in vascular endothelial cell and tumour cell adhesion, lymphocyte trafficking, tumor growth and viral infection. Current understanding of the molecular basis of integrins as viral receptors has been achieved through many decades of study into the biology of transmembrane glycoproteins and their interactions with several viruses. This review provides a summary of the current knowledge on the molecular bases of interactions between viruses and integrins, which are of potential practical significance. Inhibition of virus-integrin interactions at the points of virus attachment or entry will provide a novel approach for the therapeutic treatment of viral diseases.

Identification of a putative cellular receptor 150 kDa polypeptide for porcine epidemic diarrhea virus in porcine enterocytes

Porcine epidemic diarrhea virus (PEDV) causes an acute enteritis in pigs of all ages, often fatality for neonates. PEDV occupies an intermediate position between two well characterized members of the coronavirus group I, human coronavirus (HCoV-229E)and transmissible gastroenteritis virus (TGEV) which uses aminopeptidase N (APN), a 150 kDa protein, as their receptors. However, the receptor of the PEDV has not been identified yet. A virus overlay protein binding assay (VOPBA) was used to identify PEDV binding protein in permissive cells. The binding ability of PEDV to porcine APN (pAPN) and the effects of pAPN on infectivity of PEDV in Vero cells were also investigated. VOPBA identified a 150 kDa protein, as a putative PEDV receptor in enterocytes and swine testicle (ST) cells. Further the PEDV binding to pAPN was blocked by anti-pAPN and pAPN enhanced PEDV infectivity in Vero cells. In conclusion, these results suggested that pAPN may act as a receptor of PEDV.

Definition of the peptide mimotope of cellular receptor for hepatitis C virus E2 protein using random peptide library

BACKGROUND: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell . METHODS: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. RESULTS: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patient s captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. CONCLUSION: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

Integrin and Foot-and-mouth Disease Virus Infection / 微生物学通报

Integrins are a family of cell surface glycoproteins that contribute to a variety of biological functions, including cell growth, migration, proliferation and morphology. In addition, integrins also play the important roles in pathological process. Several viruses have been showed to use integrins as receptors or co-receptors to infect host cells.This article mainly reviews the progress on integrins and their roles in FMDV infection.