A mosaic renal myeloid subtype with T-cell inhibitory and protumoral features is linked to immune escape and survival in clear cell renal cell cancer

Mononuclear phagocytes moderate tissue repair, immune activation and tolerance. In the renal tubulo-interstitium specialized dendritic cells help maintain homeostasis and protect tubuli from immune injury. Human renal cell carcinoma (RCC) is immunogenic; yet immunotherapies that target T-cell dysfunction show limited clinical efficacy suggesting additional mechanisms of immunoinhibiton. We previously described enriched-in-renal cell carcinoma (erc)DCs that are often found in tight contact with T cells which are dysfunctional. Here we describe that ercDCs exhibit a distinct polarization state imparted by tissue-specific signals characteristic for RCC and renal tissue homeostasis. The resulting mosaic transcript signature includes features associated with host defense activity, angiogenesis/invasion and T-cell inhibition. An ercDC-specific profile was predictive for patient survival and suggests potential therapeutic targets for improved immunotherapy.