The Diversity of T Cell Activation Antigens. Serological Analysis Including Their Expression on Non-T Acute Lymphoblastic Leukemia Cells and B Cell Lines Derived from Adult T Cell Leukemia Patients

Activated T cells display new cell surface antigens which are not expressed on resting T cells (1). Some of these T cell activation antigens have been shown to have important roles in immunological function of T cells. For example, the Tac antigen with a molecular weight (M.W.) of 55,000 on in vitro activated T cells (2,3) proved to be the interleukin-2 receptor (4). Tac antigen is also expressed on adult T cell leukemia (ATL) cells (5,6) which are infected with ATL virus (ATLV). (7). These combined observations imply a relationship between ATLV infection and expression of Tac antigen on ATL cells.