Selective expansion of gammadelta T cells among liver-derived lymphocytes of AIDS patients with disseminated Mycobacterium avium complex infection.

The aim of this study was to investigate a potential expansion of gammadelta T cells in AIDS patients in response to disseminated infection with Mycobacterium avium complex. Liver-derived lymphocytes and peripheral blood lymphocytes were obtained from 5 AIDS patients with disseminated Mycobacterium avium complex infection and 10 HIV-infected patients without mycobacterial disease. Control patients included 14 HIV-negative patients without bacterial disease and 4 HIV-negative patients with disseminated Mycobacterium tuberculosis infection. The percentage of gammadelta T cells among CD3+ T lymphocytes was determined by flow cytometry. gammadelta T cells were markedly enhanced in liver biopsies but not among peripheral blood lymphocytes of AIDS patients with disseminated M. avium complex infection (median liver gammadelta/CD3: 26%) as compared to HIV-infected control patients without mycobacterial disease (median liver gammadelta/CD3: 2.3%; P < 0,005). Disseminated infection with M. tuberculosis in HIV-negative patients leads to a similar expansion of gammadelta T cells among liver-derived CD3+ lymphocytes (median gammadelta/CD3: 15.5%) as compared to control patients without mycobacterial disease (median gammadelta/CD3: 2.15%; P < 0,001).