阴离子交换蛋白阻滞剂DIDS对人视网膜色素上皮细胞非特异性吞噬过程的影响

目的：探讨阴离子交换蛋白在人视网膜色素上皮（RPE）细胞非特异性吞噬过程中的作用。方法：体外培养人RPE细胞，以荧光包被的乳胶株作为吞噬标记物，建立RPE细胞吞噬模型。使用不同浓度阴离子交换蛋白阻滞剂DIDS（1、10、100、200、300、500和1 000 μmol•L^-1）预处理RPE细胞，37℃孵育6 h，利用流式细胞术定量检测RPE细胞对乳胶珠的吞噬指数。结果：经6 ｈ孵育，未加DIDS的对照组RPE细胞对乳胶株的吞噬指数为(35.1±1.6)%，加入1 μmol•L^-1 DIDS的RPE细胞吞噬指数为(34.1±2.1)%（P>0.05），加入10μmol•L^-1 DIDS的RPE细胞吞噬指数为(28.7±1.9)%，10 μmol•L^-1的DIDS显著地抑制了RPE细胞对乳胶株的吞噬作用（P<0.05），并且随着DIDS浓度的增加（100、200、300、500及1 000 μmol•L^-1），RPE细胞吞噬指数逐渐降低［吞噬指数分别为(23.0±1.2)%、(17.0±1.5)%、(12.0±1.6)%、(7.0±2.2%)及(5.0±2.5)%］，与对照组比较差异均有显著性(P<0.01)。结论：抑制阴离子交换蛋白的活性将导致人RPE细胞非特异性吞噬功能的障碍，阴离子交换蛋白可能参与人RPE细胞的非特异性吞噬过程。

Effect of anion exchange blocker DIDS on nonspecific phagocytic process of human retinal pigment epithelial cells

Objective To investigate the role of anion exchange in nonspecific phagocytic process of human retinal pigment epithelial (RPE) cells. Methods Fluorescent latex beads were incubated with RPE cells at 37℃, flow cytometry was performed on RPE cells that had been challenged with fluorescent latex beads. The quantity of phagocytosis was expressed as a phagocytic index. Experiments were also performed in the presence of different concentration anion exchange blocker DIDS(1,10,100,200,300,500 and 1 000 μmol·L~ -1 ). Results Phagocytic index of RPE cells was (35.1±1.6)% at 6 h of incubation without DIDS. Phagocytic index of RPE cells was (34.1±2.1)% in the presence of 1 μmol·L~ -1 DIDS(P>0.05). Phagocytic index of RPE cells was (28.7±1.9)% in the presence of 10 μmol·L~ -1 DIDS,10 μmol·L~ -1 DIDS significantly inhibited the nonspecific phagocytic process of human RPE cells(P<0.05), and DIDS inhibited the process in concentration-dependent manner. Phagocytic index of RPE cells was (23.0±1.2)%,(17.9±1.5)%,(12.0±1.6)%,(7.0±2.2)% and (5.0±2.5)% in the presence of 100,200,300,500 and 1 000 μmol·L~ -1 DIDS (P<0.01). Conclusion The inhibition of anion exchange activity will result in the decrease of nonspecific phagocytosis in RPE cells, anion exchange maybe participate in the nonspecific phagocytic process of RPE cells.