Human immunodeficiency disease: impairment of cellular interactions leading to abnormal mediator production in mixed lymphocyte culture reaction.

Leukocyte migration inhibitory factor (LMIF) production in mixed lymphocyte culture (MLC) reactions is the result of cellular interactions based on two separate phenomena: the capacity of lymphocytes to stimulate in MLC, and the capacity of lymphocytes to respond in MLC. Puromycin-treated lymphocytes are capable of stimulating allogeneic cells for LMIF production, but are unable to respond with synthesis of LMIF (one-way MLC-LMIF test). We have studied the stimulating and responding capacity of lymphocytes from patients with different immunodeficiency syndromes in a one-way MLC-LMIF assay. Lymphocytes from patients known to have qualitative and quantitative defects of T cell or B cell functions (Hodgkin's disease, mycosis fungoides, thymoma, chronic lymphatic leukemia) were found to respond poorly as measured by mediator production although their stimulating fuction was frequently retained. Patients with advanced solid tumors often had both MLC-stimulating and responding functions depressed. There was no apparent correlation between mitogen response and MLC-induced LMIF responses or between MLC proliferative response (as measured by thymidine incorporation) and mediator production. Studying of stimulatory and responding capacity of lymphocytes in the MLC-LMIF assay provides a new tool for assessing immunocompetence and allows for in vitro evaluation of cellular interactions that may play an important role in vivo.