ANALYSES OF FUNCTIONAL ANTIBODY-RESPONSES IN HIV-1-INFECTED INDIVIDUALS AFTER VACCINATION WITH RGP160

Background: The immune response to HIV infection has been extensively studied and the antibody response against the virus has been character ized in detail. It is, however, still unclear which immune function it is most important to stimulate when administering a vaccine against H N. Objectives: To analyze the functional antibody responses in asympto matic HIV-1-infected individuals after vaccination with rgp160. Study design: Forty-nine asymptomatic HIV-1-infected individuals were follow ed For 9 months and analyzed for changes in functional antibody respon ses. Forty of them received HIV-1 envelope rgp160 injections and nine did not. Results: Increased levels of antibodies mediating neutralizat ion and cellular cytotoxicity (ADCC) could be seen in subjects who als o showed a better CD4 development compared with the patients without i ncreased levels of functional antibodies. Out of nine matched HIV-infe cted and influenza-immunized controls, none had increased neutralizing activity and only one had an increased ADCC titer. An increased capac ity to block soluble CD4 binding to gp120 occurred in 10 immunized pat ients. Seroreactivity and avidity maturation were detectable to peptid es representing consensus HIV-1 envelope regions, indicating an anamne stic response to the patients own virus. Conclusions: The humoral immu ne response in HIV-1-infected individuals was moderately influenced by repeated gp160 immunizations, while previous studies have shown that HIV-specific T-cell reactivity was strongly increased.