Identification of human immunodeficiency virus (HIV) envelope type-specific T helper cells in an HIV-infected individual.

Two T helper cell clones recognizing the gp 120 envelope protein of HIV were generated from the peripheral blood of a healthy seropositive individual. These cells were type specific as they proliferated and produced IL 2 when stimulated by an epitope in the amino-terminal half of gp 120 of HIVSF2, but not by a similar region of HIVZr6, a Zairian HIV-1 isolate. These two viruses differ by 26% in the deduced amino sequence of the gp 120 protein. Moreover, the antigenic site(s) recognized by the cloned T cells are distinct from those recognized by envelope-specific antibodies. These observations have important implications for the development and use of anti-HIV vaccines.