Small GTPase Rac1 regulates apoptosis and phagocytosis in A549 cell line
QI Chen1, PENG Jing-jing1, ZHANG Dan-yi1,2, SU Zhao-liang1,3, WANG Sheng-jun1,2, XU Hua-xi1
（1. Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang Jiangsu 212013; 2. Department of Laboratory Medicine, the Affiliated People′s Hospital of Jiangsu University, Zhenjiang Jiangsu 212002; 3. the Central Laboratory, the Fourth Affiliated Hospital of Jiangsu University, Zhenjiang Jiangsu 212001, China)
Abstract：Objective: To investigate the Rac1 expression level, and analyze the effect of Rac1 on the clearance of apoptotic cells and regulation of phagocytosis in A549 cell line. Methods: A549 cell was selected as the cell model.The curcumin was used to induce apoptosis, and the A459 cells and apoptotic cells coculture method was used for analyzing the relationship between the downregulation of Rac1 function and the ability of apoptotic cell clearance.The qRTPCR was used to detect the expression level of Rac1 mRNA.Flow cytometry and fluorescence microscopy techniques were used to observe and analyze the apoptotic cells and phagocytic capacity. Results: Flow cytometry and Hoechst staining showed that the apoptotic rate of airway epithelial cells was increased in the presence of Rac1 inhibitor, and this phenomenon was dose dependent.Flow cytometry analysis showed that the Rac1 inhibitor could markedly downregulate the phagocytic ability in A549 airway epithelial cells. Conclusion: The expression of Rac1 plays a negative role in the regulation of A549 cell apoptosis, but has a significantly effect on the phagocytosis of epithelial cells.
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2017, Vol. 27 
