Rapid characterization of HIV clade C-specific cytotoxic T lymphocyte responses in infected African children and adults

Cytotoxic T lymphocytes (CTL) play a central role in successful control of HIV. Induction of effective CTL responses may therefore be an essential requirement of HIV vaccines. Knowledge of CTL epitopes targeted either in natural infection or following vaccination will be critical to understanding the anti-HIV immune response. Until recently, epitope definition was a slow and laborious process that could only be undertaken in laboratories specialized in this work. Recent incremental advances in the technologies that may be applied to this field have transformed what is possible, so that within 48 hours of receipt of a blood sample, novel epitopes may be optimized and the HLA restriction defined. Moreover, these technologies can now be applied in nonspecialized laboratories, so that new epitopes can be characterized locally in sites where the epidemic is most severe. Sub-Saharan Africans and C clade infection have been relatively neglected in terms of the HIV-specific CTL epitopes that have been defined to date. This review summarizes the evidence that cellular immunity is important in successful containment of HIV and describes the novel methods of epitope detection, illustrating their ready application to the study of C-clade infected persons in sub-Saharan Africa.