Production of thymocyte-stimulating factor by murine spleen lymphocytes: cellular and biochemical mechanisms

Migration inhibition of normal rat thymocytes as an in vitro method for detecting cell-mediated immunity in rat and mouse

Normal rat thymocytes were used as a migrating population to study the effect of migration inhibition factor (MIF) released by sheep red blood cell (SRBC) immune lymphocytes. Normal thymocytes (migrating cells), SRBC (target antigen) and SRBC immune lymphocytes (effector cells) were packed in capillary tubes and their migration studied. This migration inhibition assay proved to be a very good in vitro correlate of specific delayed type hypersensitivity against SRBC, a particulate antigen, in rats. Normal rat thymocytes could also be used to study the specific immune reactivity of murine lymphocytes sensitised to SRBC. SRBC immune rat thymocytes functioned as both the migrating cell population and MIF producing cells. This assay permitted study of the interaction between thymocytes and lymphocytes from rats in producing enhanced inhibition of cellular migration. A major advantage of the technique is the possibility of assaying a large number of replicates from abundant normal thymocytes.

DNA synthesis-potentiating activity on mouse thymocytes of synovial fluid of rheumatoid arthritis patients

DNA synthesis-potentiating activity in synovial fluids of rheumatoid arthritis (RA) patients was studied in vitro by using phytohemagglutinin-stimulated mouse thymocytes. The activity was present only in fluids obtained during the active RA phase, and no activity was noted in fluids obtained during the inactive RA phase or in fluids of osteoarthritis deformans patients.