Natural killer and antibody-dependent cytotoxic activities in T cell chronic lymphocytic leukemia.

T cells from a patient with T cell chronic lymphocyte leukemia (CLL) were analysed for natural killer (NK) and antibody-dependent cytotoxicity (ADCC) and surface phenotype using a battery of monoclonal antibodies. T cells from the patient reacted with a pan T cell (9.6) and OKT8 (suppressor/cytotoxic phenotype) monoclonal antibodies and bore receptors for IgG Fc (Tg) but lacked receptors for IgM Fc (Tm) and did not react with OKT4 (helper/inducer phenotype) monoclonal antibody. T cells from the patient demonstrated a significantly higher (p less than 0.01) NK activity when compared to control T cells. T cells from the patient also demonstrated strong but comparable ADCC when compared to healthy controls. The significance of these results is discussed.