title: Functional versus phenotypic analysis of T cells in subjects seropositive for the human immunodeficiency virus: a prospective study of in vitro responses to Cryptococcus neoformans.
abstract: We performed a prospective study of 50 subjects at high risk for human immunodeficiency virus (HIV) infection to determine if assays of antigen-specific T cell function provide an earlier indication of future progression to AIDS or a better assessment of immune function than do current methods of evaluation. We measured in vitro T cell responses to Cryptococcus neoformans and tetanus toxoid, response to mitogens, HIV p24 antigenemia, and clinical parameters. Progression to AIDS was significantly associated with loss of T cell response to cryptococci (P = .015), HIV antigenemia (P = .001), and low CD4+ cell numbers (P = .001). Most importantly, we found that loss of antigen-specific responses to cryptococci and tetanus can occur before changes in CD4 cell number. Abnormal response to mitogens and marked depletion of CD4+ cells were late signs of progressive HIV infection. Measurement of antigen-specific T cell function may be useful for assessing the efficacy of antiviral therapy in HIV infection before onset of symptoms.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D000945:Antigens, Differentiation, T-Lymphocyte; D015331:Cohort Studies; D003454:Cryptococcus / Q000276:immunology*; D003455:Cryptococcus neoformans / Q000276:immunology*; D005500:Follow-Up Studies; D006678:HIV / Q000276:immunology*; D015488:HIV Antigens / Q000032:analysis; D006801:Humans; D008213:Lymphocyte Activation; D008297:Male; D010641:Phenotype; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D013745:Tetanus Toxoid / Q000276:immunology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D015488:HIV Antigens; D013745:Tetanus Toxoid