Transcriptional landscape of human tissue lymphocytes unveils uniqueness of tumor-infiltrating T regulatory cells

To assess the gene expression landscape of tumor infiltrating CD4+ T cells, we isolated different CD4+ lymphocytes subsets from two different tumors, NSCLC and CRC, from the adjacent normal tissues, and from peripheral blood samples. From all these tissues, we purified by flow cytometry CD4+ Treg (36 samples from 18 individuals), Th1 (30 samples from 21 individuals) and Th17 (22 samples from 14 individuals) cells. The polyadenylated RNA fraction extracted from the sorted CD4+ Treg, Th1 and Th17 cells was then analyzed by paired-end RNA sequencing.