肿瘤来源的IgG抑制脐带血中T细胞的增殖

目的 探究肿瘤来源的IgG是否对T细胞活化具有抑制作用。方法 首先从卵巢癌肿瘤组织纯化了肿瘤来源的IgG(tumor derived IgG, tIgG),并从脐带血中分离出单个核细胞(cord blood mononuclear cells,CBMC)及淋巴细胞(cord blood lymphocyte,CBL),用植物血球凝集素(phytohaemagg lutinin,PHA)刺激单个核细胞和淋巴细胞,使单个核细胞与淋巴细胞处于增殖状态,用荧光染料羟基荧光素二醋酸盐琥珀酰亚胺酯(carboxyfluorescein succinimidyl amino ester,CFSE)染色,CFSE对细胞无毒性,可以穿透细胞膜,在活细胞内与胞内蛋白结合,其荧光强度会随着细胞的分裂增殖而逐级递减,从而可以检测细胞增殖的情况。把从卵巢癌肿瘤组织中纯化得到的tIgG分为1 mg/L、10 mg/L和100 mg/L组,分别加入到单个核细胞和淋巴细胞中,静脉注射用免疫球蛋白(intravenous immunoglo-bulin,IVIG)作为阳性对照,也分为1 mg/L、10 mg/L和100 mg/L组,磷酸缓冲盐溶液(phosphate buffer saline,PBS)作为阴性对照,用细胞流式术检测CD4⁺及CD8⁺ T细胞的增殖能力,并分别在64 h和86 h两个时间点检测细胞的增殖情况。结果 在CBMC体系中加入的tIgG可以明显地抑制CBMC中T细胞的增殖,发挥免疫抑制作用;同样,在CBL体系中加入的tIgG对T细胞也有抑制作用,且加入tIgG刺激的T细胞比加入IVIG刺激的T细胞的抑制增殖作用更强;在CBL体系中,tIgG的1 mg/L组和10 mg/L组对T细胞发挥的抑制增殖作用比100 mg/L组弱。结论 tIgG可以抑制T细胞的增殖,促使肿瘤发挥肿瘤免疫逃逸效应。

Tumor derived IgG suppress the proliferation of T cells in cord blood

Objective:To explore the function of tumor derived IgG (tIgG) and whether the tIgG can inhibit T cells activity.Methods:The tIgG was purified from ovarian cancer tissue.The cord blood monocyte cells (CBMC) and cord blood lymphocyte (CBL) were isolate from human umbilical cord blood.The CBMC and CBL were stimulated with phytohaemagg lutinin (PHA) in order to let the CBMC and CBL in the state of proliferation.Carboxyfluorescein succinimidyl amino ester (CFSE) was cultured with CBMC and CBL.CFSE had no cell toxicity,which could penetrate through the cell membrane and combine the intracellular protein.The fluorescence intensity decreased with the proliferation of cells step by step,so the proliferation of these cells could be detected in flow ctytometry.The tlgG which was puri fied from ovarian cancer tissue was divided into three groups,1 mg/L group,10 mg/L group,and 100 mg/L group,and the intravenous immunoglobulin (IVIG) was also divided into three groups too.The CBMC and CBL were treated by tIgG with 1 mg/L,10 mg/L,and 100 mg/L in order to observe the proliferation of T cells.The cells were treated with IVIG as a positive control group,and the cells were treated with phosphate buffer saline (PBS) as a negative control.The proliferation of CD4 + or CD8 + T cells were detected in CBMC and CBL.The proliferation of the T cells in CBMC and CBL after 64 h and 86 h were detected.Results:In the system of CBMC,the tIgG could suppress the proliferation of CD4 + or CD8 + T cells.The results could also be found in the system of CBL.The CD4 + or CD8 + T cells in the group which were treated with PBS were more active than those in the group which were treated with tIgG and IVIG.The suppression in the group which were treated with tIgG,was stronger than that in the group treated with IVIG.In addition,the suppression of T cells in the group which were stimulated with tIgG as 100 mg/L was more effective than that in the group which were stimulated with tIgG as 10 mg/L.This could prove that tIgG had the function of immunomodulation.Conclusion:The tIgG can be involved in immune escape of cancer.