[Prediction of Anti-Tumor Immunity-Significance of a Novel Th1-Like CD4+ T-Cell Cluster].

Anti-tumor T-cell immunity invigorated by immune checkpoint inhibitors(ICI)mediate anti-tumor effects over the years, resulting in long-term survival. However, the ICI effects vary greatly from patient to patient, and accurate prediction of the effects is still not possible. Long-term anti-tumor T-cell immunity requires that the cancer immunity cycle remain in operation. It is CD4+ T cells that direct the priming, migration and infiltration abilities, and the acquisition of cytolytic functions of CD8+ T cells and drive the cancer immunity cycle. CD4+ T cells undergo functional differentiation called polarization when they are primed in lymph nodes, and they perform their predetermined functions throughout the body. For this reason, the information collected from peripheral blood can reflect the tumor microenvironments. It has been shown in mouse models that CD4+ T cells that polarize into type 1 helper T cells(Th1)are important for anti-tumor immunity. On the other hand, it has been reported that CD4+ T cells that are responsible for the anti-tumor effects of anti-PD-1 antibody and anti-CTLA-4 antibody therapy are Th1-like, but differ from canonical Th1. In this paper, we will discuss the properties of the novel Th1-like CD4+ T-cell cluster discovered by the authors, and the prediction performance of anti-tumor T-cell immunity.