Decorin提升小鼠脾脏细胞对乳腺癌细胞系4T1的免疫响应性

Decorin promotes the immune response of mouse splenocytes in response to breast cancer cell line 4T1

目的评价高表达核心蛋白聚糖(Decorin)的小鼠乳腺癌细胞系4T1对正常小鼠脾细胞的免疫激活效应,明确Decorin对抗肿瘤免疫的调节作用。方法采用携带Decorin基因的复制缺陷型重组腺病毒Ad.DCN感染小鼠乳腺癌细胞系4T1。与小鼠脾细胞共培养3 d后,通过流式细胞术检测小鼠脾细胞的CD4+T细胞、CD8+T细胞、T记忆细胞(Tm)和T调节细胞(Treg)的百分比;利用实时定量PCR(qPCR)技术检测Th1类细胞因子IL-2、IL-12、TNF-α和IFN-γ的表达,Th2类细胞因子IL-4、IL-6、IL-10和转化生长因子β(TGF-β)的表达,以及与杀伤相关基因穿孔素与颗粒酶B的表达。结果与小鼠乳腺癌细胞系4T1共培养后,小鼠脾细胞CD4+T淋巴细胞、CD8+T淋巴细胞、Treg细胞比例无明显改变,但Tm细胞比例显著升高;同时,细胞因子、穿孔素和颗粒酶B表达下调。但是,病毒感染的4T1细胞,特别是Ad.DCN感染的4T1细胞可显著抑制Treg细胞,并部分逆转细胞因子表达的下调。结论Decorin高表达可增强正常小鼠脾脏细胞对乳腺癌细胞系4T1的免疫响应性,从而激活抗肿瘤免疫反应。

Objective We aim to evaluate the immune activation effect of breast cancer cell line 4T1 with Decorin overexpression on the mouse splenocytes,and thus identify the immunological regulation of Decorin on anti-tumor immunity.Methods Mouse breast cancer cell line 4T1 was infected by adenovirus expressing Decorin,and then cocultured with mouse splenocytes for 3 days.By FACS analysis,the percentage of CD4+T cells,CD8+T cells,memory T cell(Tm)and Treg were detected.Real-time PCR was used to detect the mRNA expression of Th1 cytokines IL-2,IL-12,TNF-αand IFN-γ,Th2 cytokines IL-4,IL-6,IL-10 and TGF-β,and cytotoxic related genes perforin and granzyme B,after coculture with 4T1 wild type cells,4T1.Null(adenovirus infection conrtol)and 4T1.DCN(with Decorin overexpression).Results Though the percentage of CD4+T,CD8+T and Treg cells were not significantly changed in splenocytes cocultured with 4T1 wild type cells,the subsets of Tm were increased.Meanwhile,the mRNA expression of cytokines,perforin and granzyme B were decreased in the splenocytes coculture with 4T1 wild type cells.However,in the 4T1.DCN and 4T1.Null group,the percentage of Treg were decreased,and the suppressed expression of Th1 and Th2 related cytokines as well as perforin and granzyme B were partly reversed as compared with the 4T1 wild type group.4T1-DCN group exerted more significant effect than 4T1.Null group.Conclusion Decorin may positively regulate the immune response of splenocytes upon stimulation by breast cancer cell line 4T1.