New research shows that melanocytes utilize PD-L1 to protect themselves from immune-mediated clearance of UV-mutated cells bit.ly/4hHmWmj @FisherLabMGH @harvardmed 👇 Lo et al. found that in melanocytes, MITF mediates upregulation of PD-L1 by binding to an enhancer, inducing high baseline PD-L1 that is further upregulated upon exposure to UVR. This mechanism has a tolerogenic effect, protecting melanocytes from immune-mediated elimination, even after the accumulation of UV-induced mutations. While this mechanism did not appear to play a major role in immune-hot melanomas with high IFNγ expression, it did show an effect in less infiltrated melanomas, and could contribute to their development.