The role of T3 surface molecules in the activation of human T cells: a two-stimulus requirement for IL 2 production reflects events occurring at a pre-translational level.

The human T cell leukemia Jurkat was used as a model to examine the requirements of T cell activation. These studies demonstrated that antibodies reactive with the T cell-specific T3 antigen were insufficient to result in the activation of Jurkat cells, determined by the secretion of IL 2. IL 2 production occurred only in the presence of a second stimulus, the phorbol ester PMA. With the use of an IL 2-specific cDNA probe, the appearance of IL 2 RNA, similarly, occurred only when cells were stimulated with both anti-T3 antibodies and PMA. These results demonstrate a two-stimulus requirement for gene expression in human T cells.