Phagocytosis of viable apoptotic cells inhibits the activation of T lymphocytes / 中国病理生理杂志

ABSTRACT

AIM: To investigate whether viable apoptotic cells and phagocytosis of them affect the activation of T lymphocytes. METHODS: Ultraviolet irradiation was used to induce apoptotic cells in vitro and the model of phagocytosis of these cells was established. Cytokine TGF ?1 was detected by ELISA. The rate of apoptotic cells and phagocytosis of them were assessed by flow cytometry. Furthermore, flow cytometry was also employed to examine the expression of activation signs, such as CD69, CD25, CD71, of T lymphocytes under the intervention of apoptotic cells and macrophage which ingested apoptotic cells, to reflect whether the apoptotic cells and the phagocytosis of these cells could influence the activation of lymphocytes stimulated by Con A. RESULTS: Ingestion of apoptotic cells increased TGF ?1 secretion. Only the macrophages that had ingested apoptotic cells could suppress the activation of lymphocytes. The expression of the markers of lymphocytes activation such as CD69, CD25, CD71 had been restrained. These inhibition effects were abolished by monoclonal anti-TGF ?1 antibody. CONCLUSION: The macrophages that have ingested apoptotic cells inhibit expression of CD69, CD25 and CD71 of T lymphocytes stimulated by ConA. This effect is dependent on the increase in TGF ?1 secretion in local site. [