Dendritic cell-intrinsic PTPN22 negatively regulates antitumor immunity and impacts anti-PD-L1 efficacy

Individuals with a loss-of-function single-nucleotide polymorphism in the gene encoding PTPN22 have an increased risk for autoimmune diseases, and patients with cancer with such alleles may respond better to checkpoint blockade immunotherapy. Studies in PTPN22 knockout (KO) mice have established it as a negative regulator of T cell responses in cancer models. However, the role of PTPN22 in distinct immune cell compartments, such as dendritic cells (DCs), remains undefined.