PTPRC and neoplasm: Since the CD45- population from isolated B16 tumors demonstrated lower protein expression of TGFβ1 and TGFβ3 compared to tumor-infiltrating Ly6C+ high monocytes (Supplementary Fig. 2b, c), we focused on characterizing the isoform-specific expression of TGFβ on tumor-infiltrating lymphoid and myeloid immune cells.