Production of interleukin 2 and expression of interleukin 2 receptors by pony peripheral blood lymphocytes after stimulation with a soluble fraction of Trypanosoma evansi.

Pony peripheral blood lymphocytes (PBL) were stimulated with a soluble fraction of Trypanosoma (T.) evansi (SF). As determined by 3H-thymidine incorporation, the cells underwent a proliferative response and were able to: a) produce a factor having the biological activities of interleukin 2 (IL-2) since their supernatants could support the in vitro growth of pony PBL stimulated with concanavalin A (Con A-blasts); b) undergo a further proliferative response when incubated in short term cultures with SF, human recombinant IL-2 (hrIL-2), or both c) bind specifically radiolabelled hrIL-2 (125I-hrIL-2). The date described here indicate that a soluble fraction of T. evansi stimulated pony PBL which subsequently produced IL-2 and expressed IL-2 receptors (IL-2R).