胰岛细胞凋亡相关因子p21ras、c-fos、TGF-β检测及其意义

An experimental detection of apoptosis related factors p21ras,c-fos,TGF-β in the cultured human embryo pancreatic islet cell

目的检测人胎成纤维细胞、胰岛细胞p21ras、TGF-β1c、-fos在不同时期的表达,进一步探讨胰岛细胞凋亡机制。方法SABC法免疫组化法检测TGF-β1、c-fos,半定量RT-PCR检测不同生长期细胞p21ras表达。结果p21ras表达成纤维细胞指数生长期强于潜伏期,停滞期最弱;胰岛细胞各生长时期均弱表达,无明显差别。TGF-β1在胰岛细胞停滞期表达强于潜伏期,指数生长期表达最弱,在胰岛细胞各生长期表达分别强于成纤维细胞各生长期。c-fos在胰岛细胞、成纤维细胞停滞期表达,在其他期不表达。结论细胞正常生长过程中,Ras可刺激成纤维细胞生长,Ras在胰岛细胞可能是Ras诱导凋亡通路未被过度激活,不发挥诱导细胞凋亡的作用。c-fos的表达可能是细胞凋亡的共同环节,并无细胞特异性。c-fos蛋白的表达对凋亡的启动可能是必须的,直接影响着细胞的生死存亡。

Objective To detect p21ras mRNA, c-fos and TGF-β protein expression of different growth periods of islet cells and fibroblast cells. Methods The expressions of c-fos and TGF-β protein were examined utilizing immunohistochemistry. Semi-quantitative RT-PCR assays were used to detect p21ras mRNA expression. Results p21ras expression of fibroblast in exponential growth period was stronger than that in incubation period and retention period. However, no significant diffierence was found in the expression of p21ras in cultured pancreatic islet cells. Islet cells had stronger TGF-β1 expression in retention period than in incubation period and exponential growth period. Nevertheless, the expression of fibroblast in different periods was weaker than that of islet cells. The expression of c-los in retention period of both islet cells and fibroblast cells could be detected, while not in incubation period and exponential growth period. Conclusion p21 ras may stimulate fibroblast cells development probably due to the low rate of apoptosis and its generations. TGF-β1 may arrest cell cycle at G1 phase, probably resulting in cell apoptosis, c-fos could be expressed before programmed cell death of both two kinds of cells, indicating its role as a common link of cell apoptosis, without cell difference.