Abstract
Studies comparing the enhancing effect of guinea pig complement on homotypic and heterotypic neutralizing antibodies produced in initial herpes simplex virus (HSV) infections of humans indicated that antibodies to HSV type 1 and HSV type 2 were enhanced to about the same extent, and there was no signigicant difference in the degree to which complement enhanced homotypic and heterotypic HSV-neutralizing antibody. Homotypic and heterotypic immunoglobulin G neutralizing antibodies were enhanced by complement to as great, or greater, an extent as immunoglobulin M (IgM) HSV antibodies in the same sera. In patients with initial HSV type 1 infections, the IgM neutralizing antibody response was type specific. On the other hand, patients with initial HSV type 2 infections produced both homotypic and heterotypic IgM neutralizing antibody. An initial HSV type 2 infection in an individual previously infected with HSV type 1 elicited the production of IgM neutralizing antibody to both HSV type 1 and HSV type 2. However, patients with recurrent HSV type 1 infections failed to produce IgM antibody to either HSV type during reactivation of the virus.