Gene expresion profile of different clusters of antigen specific CD4+ T cells induced by vaccines containing high doses of MHC-II restricted neoantigens

CD4+ T cells induced by vaccines containing high doses of mItgb1 SLP were sorted into 3 different clusters based on the expression of CD25, CD200 and CD39. We found that cluster-3 cells (CD4+ CD25- and CD39+) express high levels of GZMB, Ccl5, Lilirb4 and Sema4a. The gene signature of cluster-3 matched those of mice and human Tr1. T3 tumor-bearing 129S6 male mice were vaccinated on day 6 post-tumor implantation, and 7 days later, tumors were harvested and processed into single-cell suspension. Antigen specific CD4+ T cells were then enriched using positive selection beads and then FACS sorted into 3 differtent clusters as listed.

将经高剂量mItgb1 SLP疫苗诱导产生的CD4阳性T细胞，依据CD25、CD200与CD39的表达谱分为3个独立细胞簇。研究显示，第3簇细胞（CD4+ CD25-且CD39+）高表达GZMB、Ccl5、Lilirb4及Sema4a基因。该细胞簇的基因特征与小鼠及人源Tr1（1型调节性T细胞）的基因特征高度吻合。于肿瘤植入后第6天，对携带T3肿瘤的129S6雄性小鼠进行疫苗免疫，7天后收获肿瘤并制备为单细胞悬液。随后采用阳性分选磁珠富集抗原特异性CD4阳性T细胞，再通过FACS（荧光激活细胞分选）将其分为前述3个细胞簇。