Production of interferon ? and interleukin 4 by human thymocytes in vitroI.I. Sharova, M.M. Litvina, S.V. Shevelev, A.Kh. Dzutsev, A.A. Yar IL-inInstitute of Immunology, Moscow

Production of interferon ? and interleukin 4 by human thymocytes in vitroI.I. Sharova, M.M. Litvina, S.V. Shevelev, A.Kh. Dzutsev, A.A. Yar IL-inInstitute of Immunology, Moscow

Approximately every fourth thymocyte isolated from the first year chIL-dren thymuses contains IFN? in itscytoplasm, and every sixth cell contains IL-4. Part of the thymocytes possesses these cytokines on theirsurface. IFN? is present predominantly in mature thymocytes as well as in CD4CD8  precursors, whereasIL-4 — in immature cells of CD4CD8 and CD4+CD8+ phenotypes. Cultivation of thymocytes for 24 hr without any activation leads to the decrease of cytokine containing cells, which is probably a result of cytokine degradation in the cells. Thymocyte activation with phorbol myristic acetate plus ionomycin for 24 hrdid not change the number of IFN?+ or IL-4+ cells. However the coculture of thymocytes with thymic epithelial cells (TEC) resulted in significant elevation of IL-4+ cell number, whIL-e the co!culture with TEC andadditional activation with PMA + ionomycin elevated IFN?+ cell number as well.

Key words: human thymocytes, cytokine production, IFN?, IL-4.