角膜缘干细胞对外周血淋巴细胞活化和增殖作用的实验研究

Studies on keratolimbal stem cell to pericirculation lymphocyte activation and proliferation

目的 观察角膜缘干细胞对外周血淋巴细胞活化和增殖的抑制活性 ,并分析其机制。方法 通过植片技术分离兔角膜上皮细胞以及角膜缘干细胞。在两种细胞单层上 ,观察淋巴细胞对丝裂原刀豆蛋白A(ConA)的增殖反应。另外 ,将两种细胞培养上清直接转移到由ConA刺激的淋巴细胞增殖系统以观察两种细胞释放某些因子的抑制效应。结果 单层角膜缘干细胞对ConA刺激的外周血淋巴细胞增殖反应可以施加有效的抑制效应。角膜缘干细胞以及角膜上皮细胞的培养上清对ConA刺激的外周血淋巴细胞增殖系统 ,仅在 72h分离上清显示有抑制效应。结论 角膜缘干细胞通过细胞交互作用和 (或 )

ObjectiveTo investigate the regulation of host lymphocyte activation by the allograft of limbal stem cells.MethodsLimbal stem cells and corneal epithelial cells were isolated and cultured from domestic rabbit corneas by explant technique.The media of each cell type were collected and freeze at different time at -20℃ after purification.Lymphocytes of the New Zealand rabbit were cultured in media stimulated by conavalin A(ConA).Limbal stem cells or corneal epithelial cells of the domestic rabbits were co cultured with the lymphocytes from the New Zealand rabbits' blood.Lymphocyte proliferation assay was assessed by MTT colorimetric assay.ResultsSignificant proliferation of the lymphocytes was shown after adding the Con A.The supernatant collected the 72 h either from the limbal stem cells or the corneal epithelial cells caused a potent inhibitory effect of proliferation of lymphocytes.The domestic rabbits' limbal stem cell monolayer showed a significant suppressive effect on the allograft lymphocyte proliferation after mixed lymphocyte culture for 48 h ,but this phenomenon could not be seen in the monolayer domestic rabbits' corneal epithelium in vitro.ConclusionThe results indicate the existence of a number of possible mechanisms that worked independently or in concert to inhibit the lymphocytes proliferation.This occurs mainly by cell cell interaction and/or some other soluble factors,and limbal stem cells assume an important role in increasing the eye immune privilege.