PD-L1在胃癌患者手术前后外周血T细胞和单核细胞上的表达及意义

Expression of PD-L1 in peripheral blood T cells and monocytes of patients with gastric cancer before and after surgery and its clinical significance

目的:检测胃癌患者术前术后外周血细胞表面PD-L1的表达,探讨其表达改变及临床意义。方法:收集44例胃癌患者术前术后和18名健康志愿者外周血标本,流式细胞术检测CD3^+CD4^+T、CD3^+CD8^+T细胞表面PD-1和PD-L1以及CD14^+单核细胞表面PD-L1的表达。结果:与健康志愿者相比,胃癌患者外周血CD4^+T和CD8^+T细胞表面PD-L1表达无显著差异[(11.1±6.4)%vs(9.8±5.6)%,P=0.453 2;(13.9±12.0)%vs(12.0±7.1)%,P=0.558 9],而CD14^+单核细胞表面PD-L1表达水平显著增加[(29.2±16.7)%vs(17.5±9.7)%,P=0.007 3]。但胃癌患者术后CD4^+T细胞和CD8^+T细胞表面PD-L1的表达均显著高于术前水平[(15.8±8.2)%vs(11.1±6.4)%,P=0.001 5;(22.5±13.3)%vs(13.9±12.0)%,P=0.000 2],而术后外周血CD14^+单核细胞PD-L1表达水平并无显著变化[(33.8±17.3)%vs(29.2±16.7)%,P=0.082 8]。同时,胃癌患者手术前后外周血CD4^+T和CD8^+T细胞表面PD-1的表达无统计学差异[(25.6±9.9)%vs(26.9±8.9)%,P=0.505 5;(26.5±14.6)%vs(29.9±10.4)%,P=0.118 7]。结论:PD-L1可作为监测原发性胃癌患者的免疫功能和预后评估的有效指标。

Objective： To investigate the expression of PD-L1 in peripheral blood with gastric cancer patients and its clinical significance. Methods： Peripheral blood samples were collected from 44 gastric cancer patients（ before and after the surgery） and 18 healthy subjects. The expression of PD-1 and PD-L1 on CD3~＋CD4~＋T,CD3~＋CD8~＋T cells and CD14~＋monocytes was detected by flow cytometry. Results： The expression of PD-L1 on CD14~＋monocytes of the gastric cancer patients was significantly higher than that of the healthy control[（ 29. 2±16. 7） % vs（ 17. 5±9. 7） %,P = 0. 007 3],while there was no statistical difference on CD4~＋T cells and CD8~＋T cells[（ 11. 1±6. 4） % vs（ 9. 8±5. 6） %,P = 0. 453 2;（ 13. 9±12. 0） % vs（ 12. 0±7. 1） %,P = 0. 558 9]. The expression of PD-L1 on CD4~＋T cells and CD8~＋T cells in patients with gastric cancer was significantly higher than that before surgery [（ 15. 8 ± 8. 2） % vs（ 11. 1±6. 4） %,P=0. 001 5;（ 22. 5±13. 3） % vs（ 13. 9±12. 0） %,P=0. 000 2]. However,no significant change was found on CD14~＋mononuclear cells[（ 33. 8±17. 3） % vs（ 29. 2±16. 7） %,P = 0. 082 8]. There was no significant difference in the expression of PD-1 on CD4~＋T and CD8~＋T cells before and after surgery[（ 25. 6 ±9. 9） % vs（ 26. 9 ±8. 9） %,P = 0. 505 5;（ 26. 5 ± 14. 6） % vs（ 29. 9 ±10. 4） %,P = 0. 118 7]. Conclusion： PD-L1 can be used as an effective marker to monitor the immune function and prognosis of patients with primary gastric cancer.