scRNAseq reveals mechanisms of Merkel cell carcinoma acquired immunotherapy resistance [1]

Serial blood draws from a single patient and serial tumor biopsies from the same patient with metastatic Merkel cell polyomavirus Merkel cell carcinoma, who was treated with cellular immunotherapy targeting MCPyV (autologous endogenous T cell therapy) followed by checkpoint inhibitors (anti-PD1 and anti-CTLA4). The patient had a 22 month clinical response followed by late/acquired resistance. We performed scRNAseq using the 10x genomics 3' Chromium expression assay to determine potential mechanisms contributing to immunotherapy response and late resistance Serial blood draws from four time points, serial tumor biopsies from two time points - single cell digests were viably preserved, comparisons were performed on a within tissue basis, discovery patient for associated manuscript