HIV gp120 Plus Specific Peptides Are Recognized in a Similar Manner to Specific HLA Plus Peptide by HLA-Restricted Antigen-Specific T-Cell Lines

Abstract

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 there 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 HIVpgl20 could bind peptides in a similar manner to HLA, by demonstrating that human antigen presenting cells (APCs) expressing gp120 (but not DR1) can present a DRl-restricted peptide to induce proliferation of a DR1-restricted peptide-specific T-cell line in a similar manner to the same peptide presented by a DR1 expressing APC. Our data provide strong support for the hypothesis that the HLA-like regions of gp120 encode functional properties shared with HLA, and could explain the extraordinary clinical and immunological similarities between AIDS and chronic graft versus host disease.