Peripheral T-cell lymphomas. Immunophenotype, lymphokine production, and immunologic functional characteristics of the lymph-node malignant T cells.

Immunophenotype and functions of the malignant T cells to secrete various T-cell derived lymphokines and to respond in autologous mixed lymphocyte reaction (AMLR) and allogeneic mixed lymphocyte reaction (MLR) of the six patients with peripheral T-cell lymphomas (PTL) are presented. Three cases showed CD3/TcR alpha beta discordance (1 CD3+/TcR alpha beta-; 2 CD3-/TcR alpha beta+) and one showed absence of both these antigens (CD3-/TcR alpha beta-). In addition, we found that 50% of cases expressed CD25+, CD38+, and CD71+ activation antigens. The CD3/TcR alpha beta discordance and expressions of activation antigen noted in these cases were typical and similar to those reported from elsewhere. These malignant T cells from all cases whether CD25+ or CD25- (resting) expressed elevated interleukin-2 receptors (IL-2R) on stimulation with phytohemagglutinin (PHA) or human recombinant interleukin-2(rIL-2), and secreted elevated IL-2 by PHA, than do T cells from patients with tuberculosis (TB) or normal healthy controls. These malignant T cells also demonstrated elevated AMLR but deficient MLR B cells growth factor (BCGF) (except in one unusual case) secretion was increased, whereas B-cell differentiation factor (BCDF) secretion decreased. These results suggest that malignant T cells from lymph nodes of patients with PTL have uniform multiple immunologic defects in IL-2, BCGF, and BCDF lymphokine secretion and respond in AMLR and MLR, which do not correlate with immunophenotype or histologic types. These functions differentiate them from lymph-node T cells of patients with TB or blood T cells of normal healthy controls.