Minimal incidence of serum antibodies reactive with intact primary isolatevirions in human immunodeficiency virus type 1-infected individuals

Immunoglobulin G reactive with primary isolate virions aas detected in 36% of serum samples from individuals infected with human immunodeficiency viru s type 1. Of these individuals, serum samples from only 7% captured signifi cant quantities of virus. Virion-specific antibody correlated with CD4 coun ts and, of more significance, primary isolate neutralization. Further disse ction of this response should lead to the identification of antibodies and antigenic epitopes for vaccine purposes.