LAUSR

Background Non small cell lung cancer is one of the cancer types where Immune checkpoint blockade has demonstrated unprecedented clinical efficiency. However, only a fraction of patients benefit from such therapy; factors determining this response are yet to be elucidated. Here, we investigated whether the differentiation status of circulating CD8 T cells might be associated with outcome of PD1 blockade therapy in NSCLC. Methods We used multi-parameter flow cytometry to study CD8 T cell differentiation states in NSCLC patients at baseline and to examine the effects of blocking the PD1/PDL1 pathway on those cells. Results We found that responders to PD1 blockade therapy has more peripheral PD1+ CD8 T cells with an early-like differentiated status at baseline and that this phenotype is associated with longer survival. Moreover, PD1 blockade induced reinvigoration is mostly observed in cells with this with an early-like differentiated status. Conclusions An early like differentiation status of peripheral CD8 T cells is associated with favorable outcome of PD1 blockade immunotherapy