Production of interleukin-2 and expression of tac antigen in Hodgkin disease.

Phytohemagglutinin (PHA)- induced Interleukin-2 (IL-2) production by peripheral blood mononuclear cells was studied in 28 untreated patients with Hodgkin Disease (HD). A group of 28 patients were also investigated for the expression of Tac antigen in the resting stage of lymphocytes and after activation with PHA and mixed leukocyte culture (using anti-Tac monoclonal antibody). The blastogenic response to PHA and IL-2 production by lymphocytes of HD patients was significantly lower than that of normal lymphocytes. Production of IL-2 appeared to be severely affected in 14 of 28 HD patients who also showed PHA response less than the normal range. The Tac antigen expression was found to be lower in PHA-stimulated but not alloantigen-stimulated lymphocytes from the HD patients. No correlation was observed between the levels of IL-2 production, Tac antigen expression, and blastogenic response to PHA or allogeneic cells and the stage of disease when tested in the same patients.