The Association of p56 lck with the CD4/CD8 Antigens: Implications for T-Cell Function

The CD4 and CD8 antigens define discrete T-cell subsets involved in the restricted recognition of MHC class II and I antigens, repectively. The CD4 antigen also appears to serve as a receptor for the human immunodeficiency virus (HIV), the causative agent of AIDS. Both sets of antigens are members of the immunoglobulin superfamily and appear to synergize with the T-cell receptor complex (Ti/CD3) in the initiation of T-cell proliferation (Eichmann et al. 1986, Anderson et al. 1987). An important question has been to understand the underlying molecular basi s of CD4 and CD8 function. In this paper, we briefly review data demonstrating a physical interaction between the CD4 or CD8 antigens and the protein-tyrosine kinase p56lck and outline its potential importance in the regulation of T-cell growth.