Function of Helper T Cells in the Memory CTL-mediated Anti-tumor Immunity

Abstract

To investigate the role of CD4 + helper T (Th) cells in the memory CTL2mediated anti2tumor immunity , the RAG21 gene knock out mice were adoptively transferred with OT21 cells to generate the memory CTL , the C57BLP6 mice im2 munized with the epitope peptide of OVA specific Th cells and with different adjuvants were adoptively transferred with these memory2CTLs , and then the animals were challenged with tumor cells EG7. It was found that although the simple immuniza2 tion of mice with the epitope peptide of the OVA specific Th cells could generate more effect CTL , but this effect was not so strong enough to resist completely the challenges with tumor cells. Nevertheless , the memory CTL2mediated anti2tumor im2 mune effect required the helps of Th1 and Th2 cells. The cross2regulation between Th1 and Th2 cells seemed to be beneficial for the host to generate more effector CTL for mounting an efficient anti2tumor response. It concluded that the interaction be2 tween Th1 and Th2 cells might be more important than the single subset of Th cells in the memory CTL2mediated anti2tumor immune response. More attention should be paid in this regard for the future studies.