HIV gp120 plus specific peptides are recognized in a similar manner to specific HLA plus peptide by HLA-restricted antigen-specific T-cell lines

HIV induces disease only following chronic activation of the immune system. Other retroviruses such as the mouse mammary tumour virus (MMTV) activate a large percentage of T cells by encoding a superantigen (SAg). To date the re is no evidence that HIV encodes a SAg, An alternative way to induce pan- activation of the immune system is by allogeneic stimulation, which occurs following transplantation. Here we extend previous work which demonstrated that HIVpg120 could bind peptides in a similar manner to HLA, by demonstrat ing that human antigen presenting cells (APCs) expressing gp120 (but not DR 1) can present a DR1-restricted peptide to induce proliferation of a DR1-re stricted peptide-specific T-cell line in a similar manner to the same pepti de presented by a DR1 expressing APC, Our data provide strong support for t he hypothesis that the HLA-like regions of gp120 encode functional properti es shared with HLA, and could explain the extraordinary clinical and immuno logical similarities between AIDS and chronic graft versus host disease.