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Interleukin 2 (IL-2) is a lymphokine synthesized and secreted by lymphocytes T. Two stimuli are needed for this process: one is antigenic or mitogenic, and another is triggered by a monokine interleukin 1 (IL-1). Another consequence of these stimuli is an expression of membrane receptors for interleukin 2 (mIL-2R). The interaction of IL-2 with mIL-2R results in proliferation and differentiation of lymphocytes. Also soluble interleukin 2 receptors (sIL-2R) appear in the culture of lymphocytes. They are smaller than their membrane counterparts, but retain the ability to bind IL-2. Firs, we investigated kinetics of IL-2 and sIL-2R secretion in the culture of lymphocytes. The IL-2 concentration increases during the first 48 hours, where after it begins to decrease. The sIL-2R concentration increases during all 72 hours of the experiment, but the greatest rise is notices during first 48 hours. The production of these two molecules seems to be interdependent. As the role of tIL-2R is still unknown, we wanted to find out if any changes in IL-2 concentration occurred after continuous removal of sIL-2R from the culture of lymphocytes. We tried to remove sIL-2R by the affinity cromatography. The method exploits the capability of matrix bound antibody against IL-2R to bind sIL-2R. The efficiency of the removal of sIL-2R from the culture supernatant was determined by the enzyme-linked immunosorbent assay (ELISA). The IL-2 concentration in the cell culture was determined by the radioimmune assay (RIA). The sIL-2R concentration in the culture supernatant decreased significantly regardless of the initial concentration. In the same samples the amount of IL-2 was determined. A substantial decrease in IL-2 concentration was observed in the cell culture just after the first determination.