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Interaction of corneal epithelial cells with corneal stromal cells and lymphocytes

角膜上皮细胞与角膜基质细胞和淋巴细胞的相互作用

基本信息

批准号：
06671777
负责人：
IWATA Mitsuhiro
金额：
$ 1.02万
依托单位：
Nihon University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

Mechanisms of signal transduction for regulatory effects of IFN-gamma and TNF-alpha on MHC molecules or ICAM-1 expression on human corneal epithelial (HCE) cells were examined by flow cytometry, Western blotting, and immunoprecipitation, using cultured HCE cells.(1) Multiple strong tyrosine phosphorylation bands were detected in the IFN-gamma-treated HCE cells.(2) Pretreatment of HCE cells I and class with herbimycin A (HMA), a specific protein kinase (PTK) inhibitor, blocked the IFN-gamma induction of both MHC class II expression.(3) HMA had only a partial blocking effect on the IFN-gamma induction of ICAM-1 expression.(4) HMA inhibited the protein tyrosine phosphorylation in the HCE cells induced by IFN-gamma.(5) Both Jak1 and Jak2 molecules were detected in HCE cells.<short conclusion> These results suggested that IFN-gamma induces tyrosine phosphorylation of proteins which may mediate the IFN-gamma induction of MHC class I and class II expression on HCE cells, but mediate the IFN-gamma induction of ICAM-1 partially.(6) TNF-induced tyrosine phosphorylation of proteins which were similar but different from those by IFN-gamma in the HCE cells.(7) Inhibitory effect of TNF-alpha on IFN-gamma induction of MHC class II on HCE cells was blocked by HMA.<short conclusion> These findings suggested that TNF-alpha induces protein tyrosine phosphorylation which may mediate an inhibitory effect of TNF-alpha on the IFN-gamma -induction of MHC class II expression on HCE cells.2.Interactions between human corneal stromal (HCF) cells and HCE cells were examined.HCE cells cocultured with HCF cells expressed B7-1 molecules when stimulated by IFN-gamma, whereas HCE cells cultured alone did not express B7-1.This finding suggested that immunological function of HCE cells is enhanced by HCF through B7-1 induction on HCE cells.

以培养的人角膜上皮细胞为材料，用流式细胞术、免疫印迹和免疫沉淀等方法研究了干扰素-γ和肿瘤坏死因子-α对人角膜上皮细胞MHC分子或ICAM-1表达调控的信号转导机制：(1)经干扰素-γ处理的人角膜上皮细胞有多条强酪氨酸磷酸化条带；(3)HMA对干扰素诱导的ICAM-1表达仅有部分阻断作用。(4)HMA抑制干扰素诱导的HCE细胞蛋白酪氨酸磷酸化。(5)HCE细胞表达JAK1和JAK2分子。这些结果提示，干扰素-γ诱导蛋白酪氨酸磷酸化，可能介导干扰素-γ诱导HCE细胞表达MHC-I和II类，但部分介导干扰素-γ诱导ICAM-1的诱导。(6)肿瘤坏死因子诱导HCE细胞中与干扰素-γ相似但不同的蛋白质的酪氨酸磷酸化。2.观察了人角膜基质细胞与人角膜基质细胞的相互作用，发现与人角膜基质细胞共培养的人角膜基质细胞在干扰素-γ刺激下表达B7-1分子，而单独培养的人角膜基质细胞不表达B7-1分子。