人红白血病细胞株K562培养上清对外周血单个核细胞的影响

The effects of human erythroleukemia cell line K562 supernatant on the peripheral blood mononuclear cells

目的了解人红白血病细胞株K562分泌物对外周血单个核细胞(PBMC)的影响及其机制。方法选择K562细胞上清处理总的外周血单个核细胞(PBMC),首先用流式细胞术检测K562细胞上清对PBMC活化标志CD69和HLA-DR表达的影响,并通过改良的流式细胞术检测其增殖(数量)情况。然后进一步用流式细胞仪检测PBMC细胞的增殖指数和凋亡率以及各亚群细胞表面标志分子的表达情况。结果在K562细胞上清作用下,PBMC表面活化标志CD69和HLA-DR表达阳性细胞百分率显著增加,但是在K562细胞上清的影响下,PBMC数量明显下降。在检测对照组的增殖指数和凋亡率时,发现在培养72 h后,PBMC细胞的增殖指数明显上升,且凋亡率也显著增加。此外,在进一步对PBMC亚群的检测发现,与对照组相比,T细胞阳性细胞百分率明显下降,B细胞和单核细胞的百分率则显著上升,NK细胞无明显变化。CD4/CD8比值虽有所增加,但变化不明显。结论 K562上清虽能够诱导PBMC细胞活化,但也会诱导亚群中T细胞的大量凋亡,这可能是导致K562逃避免疫监视的原因之一。

We aimed to evaluate the effects of human erythroleukemia cell line K562 supernatant on the peripheral blood mononuclear cells（PBMCs） and investigate the mechanisms.We treated PBMCs were with K562 cell supernatants and set WI-38 cell supernatants as controls.The live PBMC numbers were determined using modified flow cytometry（FCM）.Then CD69,HLA-DR,cell cycle,apoptosis,and the molecules expressed on subsets of PBMC surface were detected with flow cytometry after the PBMCs were treated with K562 supernatants for 72 h.we found that K562 cell supernatants dramatically increased the percentage of CD69 positive cells and HLA-DR positive cells,the proliferation index,and the apoptosis,but decreased the number of live PBMCs in a concentration-dependent manner.Furthermore,K562 cell supernatants decreased the T cell subpopulation but increased B cell and monocyte subpopulation in the cultured PBMCs.After K562 cell supernatants treatment,the CD4/CD8 ratio increased slightly but not significantly.Thus,K562 cell supernatants can activate PBMCs and induce apoptosis of T cells,which might be one possible reason for tumor cells to escape from immune surveillance.