[Detection of a differentiable antigen of activated T- and B-lymphocytes (AKA-1) in tumor cells].

Antiserum to ACA-1 antigen (antigen of activated murine T and B cells) has cytotoxic activity against cells of murine tumors of lymphoid (EL-4) and non-lymphoid origin (Sa-1, AG-22, MX-11). Cytotoxicity as regards tumor cells as well as normal activated T and B lymphocytes was reduced as a result of additional absorption of antiserum with cells of all the tumors tested (but not after absorption with intact lymphocytes or liver cells of intact mice). It is concluded that ACA-1 is present on the surface of actively proliferating tumor cells. ACA-1 is assumed to be an antigenic marker of cellular activation and proliferation.