Evaluation of cytotoxic T-lymphocyte responses in human and nonhuman primate subjects infected with human immunodeficiency virus type 1 or simian/human immunodeficiency virus

Cytotoxic T-lymphocyte (CTL) responses have been implicated as playing an i mportant role in control of human immunodeficiency virus (HIV) infection. H owever, it is technically difficult to demonstrate CTL responses consistent ly in nonhuman primate and human subjects using traditional cytotoxicity as say methods. In this study, we systematically evaluated culture conditions that may affect the proliferation and expansion of CTL effector cells and p resented a sensitive method for detection of cytotoxicity responses with bu lk CTL cultures. We confirmed the sensitivity and specificity of this metho d by demonstration of vigorous CTL responses in a simian-HIV (SHIV)-infecte d rhesus macaque. The expansion of epitope-specific CTL effector cells was also measured quantitatively by CTL epitope-major histocompatibility comple x tetramer complex staining. In addition, two new T-cell determinants in th e SIV gag region are identified. Last, we showed the utility of this method for studying CTL responses in chimpanzee and human subjects.