Better neutralization of HSV-1 than HSV-2 by antibody from subjects immunized with the GlaxoSmithKline gD2 vaccine.

The Journal of Infectious Diseases (Impact Factor: 5.78). 03/2014; DOI: 10.1093/infdis/jiu177
Source: PubMed

ABSTRACT The Herpevac Trial evaluated an HSV-2 glycoprotein D (gD2) subunit vaccine to prevent genital herpes. Unexpectedly, the vaccine protected against genital HSV-1 but not HSV-2. We evaluated sera from 30 HSV-1 and HSV-2 seronegative women immunized with gD2 in the Herpevac Trial. Neutralizing antibody titers were 3.5-fold higher to HSV-1 than HSV-2 (P<0.001). HSV-2 glycoproteins C (gC2) and E (gE2) on the virus blocked neutralization of gD2, while HSV-1 gC1 and gE1 did not block neutralization of HSV-1. The higher neutralizing antibody titers to HSV-1 offer an explanation for the Herpevac results and shielding neutralizing domains provides a potential mechanism.

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