Immune response to immunostimulatory complexes (ISCOMs) prepared from human immunodeficiency virus type 1 (HIV-1) or the HIV-1 external envelope glycoprotein (gp120)

In mice, immunostimulatory complexes (ISCOMs) prepared from HIV-1 B external envelope glycoprotein (gp120) induced 10-fold higher antibody titres than gp120 emulsified in depot adjuvant, as measured by enzyme-linked immunosorbent assay (ELISA). Rhesus monkeys immunized with gp120 ISCOMs produced precipitating and virus neutralizing antibody titres equivalent to those seen in HIV-infected chimpanzees and humans. After multiple immunizations with HIV-1 B gp120 ISCOMs, a rhesus monkey developed a neutralizing response to the HIV-1 isolates RF and MN, but not to the CC isolate. Antisera from ISCOM-immunized rhesus monkeys recognized gp120 on the membranes of HIV-1 B-infected H9 cells, indicating the preservation of epitope structure in the ISCOMs matrix.