Upregulation of phagocytic clearance of apoptotic cells by autoimmune regulator

Abstract

To investigate the effect of autoimmune regulator (AIRE) on phagocytic clearance of apoptotic cells, a recombinant expression vector containing full-length human AIRE cDNA was transfected into 16HBE cells. After incubation with transfected 16HBE cells, engulfment of apoptotic HL-60 cells induced by camptothecin was detected by myeloperoxidase (MPO) staining. The change in the expression of Rac 1 in transfected 16HBE cells was determined by RT-PCR and Western blotting. The results showed that the phagocytosis percentage of the experimental group, the mock transfection group and the negative control group (non-apoptotic cells) was (25.50±3.67)%, (6.25±1.58)% and (1.0±0.67)%, respectively. Moreover, the expressions of Rac 1 mRNA and protein were up-regulated in AIRE-transfected 16HBE cells, suggesting that AIRE may function as a regulator in the phagocytic clearance of apoptotic cells by promoting the expression of Rac 1.

Keywords

autoimmune regulator / apoptosis / phagocytosis / rac1 protein

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