γδ T lymphocyte responses to HIV

Abstract

SUMMARY Natural immunity may be involved in controlling viral spread in hosts infected with HIV. A panel of γδ T cell receptor-positive lymphocyte clones was isolated from the peripheral blood of healthy HIV− donors and tested for anti-HIV cytotoxic responses. Twelve of 30 (40%) Vγ9+Vδ2+ T cell clones, but none of seven Vδ1+ T cell clones, displayed lytic activity against HIV-infected cells. The Vγ9+/Vδ2+ clones cytotoxic for HIV-infected cells also lysed Daudi cells. However, not all Vγ9+/Vδ2+ clones which lysed Daudi targets had the capacity to lyse HIV-infected cells. Some of the γδ T cell clones were also investigated for potential proliferative responses to HIV-infected cells. One Vγ9+/Vδ2+ T cell clone (ME8-7) and one Vδ1+ T cell clone (ME18-2) demonstrated proliferative responses toward HIV-infected cells. Another Vγ9+/Vδ2+ clone (VM39) proliferated in response to cell-free HIV. Taken together, these results provide direct evidence of anti-HIV γδ T cell responses in healthy, HIV− persons.