Integrin alpha3beta1 (CD 49c/29) is a cellular receptor for Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8)

Shaw M Akula1, Naranatt P Pramod, Fu Zhang Wang

  • 1Department of Microbiology, Molecular Genetics and Immunology, The University of Kansas Medical Center, Kansas City, KS 66160, USA.

Cell
|February 21, 2002
PubMed

Human herpesvirus-8 (HHV-8) is implicated in the pathogenesis of Kaposi's sarcoma. HHV-8 envelope glycoprotein B possesses the RGD motif known to interact with integrin molecules, and HHV-8 infectivity was inhibited by RGD peptides, antibodies against RGD-dependent alpha3 and beta1 integrins, and by soluble alpha3beta1 integrin. Expression of human alpha3 integrin increased the infectivity of virus for Chinese hamster ovary cells. Anti-gB antibodies immunoprecipitated the virus-alpha3 and -beta1 complexes, and virus binding studies suggest a role for alpha3beta1 in HHV-8 entry. Further, HHV-8 infection induced the integrin-mediated activation of focal adhesion kinase (FAK). These findings implicate a role for alpha3beta1 integrin and the associated signaling pathways in HHV-8 entry into the target cells.

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