Immunization with a Vaccine Combining Herpes Simplex Virus 2 (HSV-2) Glycoprotein C (gC) and gD Subunits Improves the Protection of Dorsal Root Ganglia in Mice and Reduces the Frequency of Recurrent Vaginal Shedding of HSV-2 DNA in Guinea Pigs Compared to Immunization with gD Alone

• Published in: Journal of Virology Vol. 85; no. 20; pp. 10472 - 10486
• Main Authors: Awasthi, Sita, Lubinski, John M, Shaw, Carolyn E, Barrett, Shana M, Cai, Michael, Wang, Fushan, Betts, Michael, Kingsley, Susan, DiStefano, Daniel J, Balliet, John W, Flynn, Jessica A, Casimiro, Danilo R, Bryan, Janine T, Friedman, Harvey M
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01-10-2011
• Subjects: Animals; Antibodies, Neutralizing - blood; Antibodies, Viral - blood; antigens; Biological and medical sciences; CD4-positive T-lymphocytes; CD4-Positive T-Lymphocytes - immunology; complement; DNA; Female; Fundamental and applied biological sciences. Psychology; ganglia; Ganglia, Spinal - immunology; glycoproteins; Guinea Pigs; Herpes Genitalis - immunology; Herpes Genitalis - prevention & control; Herpes Zoster - immunology; Herpes Zoster - prevention & control; Herpes Zoster Vaccine - administration & dosage; Herpes Zoster Vaccine - immunology; Herpesvirus 2, Human - immunology; Human herpesvirus 2; immune evasion; immunization; Immunization - methods; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Microbiology; Miscellaneous; neutralization; neutralizing antibodies; Secondary Prevention; synthetic vaccines; Vaccines and Antiviral Agents; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies; Vagina - virology; Viral Envelope Proteins - immunology; viral proteins; viral shedding; Virology; Virus Shedding; Immunization; Root; Herpesviridae; Alphaherpesvirinae; Rodentia; Glycoprotein; Vagina; Vaccine; Subunit; Virus; Vertebrata; Mammalia; Guinea pig; Mouse; Dissemination; Female genital system; Human herpesvirus 2
• ISSN: 0022-538X; 1098-5514
• DOI: 10.1128/JVI.00849-11

Attempts to develop a vaccine to prevent genital herpes simplex virus 2 (HSV-2) disease have been only marginally successful, suggesting that novel strategies are needed. Immunization with HSV-2 glycoprotein C (gC-2) and gD-2 was evaluated in mice and guinea pigs to determine whether adding gC-2 to a gD-2 subunit vaccine would improve protection by producing antibodies that block gC-2 immune evasion from complement. Antibodies produced by gC-2 immunization blocked the interaction between gC-2 and complement C3b, and passive transfer of gC-2 antibody protected complement-intact mice but not C3 knockout mice against HSV-2 challenge, indicating that gC-2 antibody is effective, at least in part, because it prevents HSV-2 evasion from complement. Immunization with gC-2 also produced neutralizing antibodies that were active in the absence of complement; however, the neutralizing titers were higher when complement was present, with the highest titers in animals immunized with both antigens. Animals immunized with the gC-2-plus-gD-2 combination had robust CD4+ T-cell responses to each immunogen. Multiple disease parameters were evaluated in mice and guinea pigs immunized with gC-2 alone, gD-2 alone, or both antigens. In general, gD-2 outperformed gC-2; however, the gC-2-plus-gD-2 combination outperformed gD-2 alone, particularly in protecting dorsal root ganglia in mice and reducing recurrent vaginal shedding of HSV-2 DNA in guinea pigs. Therefore, the gC-2 subunit antigen enhances a gD-2 subunit vaccine by stimulating a CD4+ T-cell response, by producing neutralizing antibodies that are effective in the absence and presence of complement, and by blocking immune evasion domains that inhibit complement activation.