重组hIFN-α-2b-BCG对人外周血免疫细胞因子表达调节及抗膀胱肿瘤作用的实验研究

Study of the Effects of Recombinant hIFN-α-2b-BCG on the Expression of Cytokines in PBMCs and Bladder Cancer Cells in Vitro

目的:探讨重组卡介苗(bacilli Calmette-Guérin BCG)对人外周血单个核细胞(peripheral blood monocytes,PBMC)IFN-γ、IL-12和TNF-α细胞因子表达、免疫增强及抗肿瘤效应。方法:重组BCG、野生型BCG和外源性人IFN-α-2b+野生BCG,分别与PBMC共同培养,以单纯PBMC为对照,在不同时段收集培养液上清,经ELISA法检测上清液中IFN-γ、IL-12和TNF-α的表达水平;将BCG激活杀伤细胞(bacilli Calmette-Guérin activated killercell,BAK细胞)与人膀胱肿瘤细胞EJ细胞共同培养,采用乳酸脱氢酶释放试验(LDH)检测活化免疫细胞的抗肿瘤效果。结果:重组BCG诱导PBMC产生细胞因子的表达明显高于同浓度的野生型BCG组和野生型BCG+外源性人IFN-α-2b组(P<0.05);重组BCG诱导的PBMC抗癌效应均高于对照组诱导的抗癌效果(P<0.05)。结论:重组BCG诱导人PBMC高表达IFN-γ、IL-12和TNF-α,并通过增强人PBMC细胞因子的表达来提高抗膀胱肿瘤作用。

Objective： To investigate the expression of cytokines including IFN-β, IL-12 and TNF-α secreted by PBMCs after stimulation with recombinant Bacille Calmette-Guerin （BCG）, and to study the anti-tumor effect of BCG-activated killer cells （BAK）. Methods： Recombinant hlFN-α-2b-BCG, wild-type BCG and wild-type BCG＋ hIFN-α-2b were used to stimulate the peripheral blood mono- cytes （PBMC） in different concentrations in vitro. Supernatant was collected at various time points and IFN-γ, IL-12 and TNF-α were detected by an enzyme-linked immunosorbent assay （ELISA）.＇The data from every combination of two groups among the three were contrasted after statistical analysis. Resuits： Compared with the other groups, recombinant BCG can induce higher density cytokines than wild-type BCG or wild-type BCG＋ hIFN-α-2b （P〈0.05）. The results of the LDH release assay show that the antitumor activity of BAK cells stimulated by recombinant BCG has the highest cytotoxicity of all of the groups. Conclusions： The expression of IFN-γ, TNF-α, and IL-12 in PBMCs stimulated by recombinant BCG is higher than those levels in cells stimulated by wild type BCG, suggesting enhanced antitumor activity of BAK when cells are treated with recombinant BCG.