Substantial effort is being invested in the search for peripheral or intratumoral
T cell receptor (TCR) repertoire features that could predict the response to
immunotherapy. Here we demonstrate the utility of MiXCR software for TCR and
immunoglobulin repertoire extraction from
RNA-Seq data obtained from sorted
tumor-infiltrating T and B cells. We use this approach to extract TCR repertoires from
RNA-Seq data obtained from sorted
tumor-infiltrating CD4+ and CD8+ T cells in an HKP1 (KrasG12Dp53-/-) syngeneic mouse model of
lung cancer after anti-PD-1 treatment. For both subsets, we demonstrate decreased TCR diversity in response to
therapy. At a later time point, repertoire diversity is restored in progressing disease but remains decreased in responders to
therapy in both CD4+ and CD8+ subsets. These observations
complement previous studies and suggest that stably increased intratumoral CD4+ and CD8+ T cell clonality after anti-PD-1/PD-L1
therapy could serve as a predictor of long-term response.