Lewis lung cancer cells affect CD4~+ CD25~+ Treg cells via TLR9 / 中国免疫学杂志

ABSTRACT

Objective:To explore the influence of tumor cells on CD4~+ CD25~+ Treg cells via TLRs.Methods:The numbers changes of CD4~+ CD25~+ Treg cells in the co-culture system of Lewis lung cancer cells and splenic lymphocytes were detected by flow cytometry;The expression of Foxp3 and TLR1-9 mRNA after co-culture were detected by RT-PCR;TLR9 expression on Lewis lung cancer cells was blocked by TLR9 receptor antagonist chloroquine.Results:Compared with control group,the number of CD4~+ CD25~+ Treg cells and Foxp3 mRNA expression were significantly increased in the co-culture group (P＜0.05).The expression of a variety of TLRs were affected by the co-culture of lymphocytes with Lewis lung cancer cells,and TLR9 mRNA expression was significantly increased compared with that of the control group (P＜0.05);Blocking TLR9 of Lewis lung cancer cells significantly reduce CD4~+ CD25~+ Treg cells and Foxp3 mRNA (P＜0.05).Conclusion:Lewis lung cancer cells could increase both number and function of CD4~+ CD25~+ Treg cells through inducing TLR9 expression in immunocells.This might be one of mechanisms of tumor-induced immune tolerance,and by which to contribute to the occurrence and progression of tumors.