Extrathecal and intrathecal IgG response to the AIDS virus LAV/HTLV-III in experimental infection of chimpanzees.

Seven of seven chimpanzees inoculated with LAV/HTLV-III and three of three chimpanzee-to-chimpanzee passages seroconverted for LAV/HTLV-III as tested by ELISA and immunoblotting. Serum IgG reactivity to gag-gene products emerged between 3 and 6 weeks after inoculation, p24gag reactivity always reaching maximum titers first. Serum IgG antibodies to env-related proteins occurred 11-21 weeks after inoculation. Throughout the observation period (greater than 36 weeks), IgG reactivity to gag, pol, and env gene products persisted. Matched serum and cerebrospinal fluid (CSF) from three LAV/HTLV-III-infected chimpanzees were available in the chronic phase of infection and titers of viral antibody and albumin and IgG content were determined. By calculation of antibody/albumin indices, evidence was obtained for intrathecal synthesis of IgG antibodies to LAV/HTLV-III in one animal.