Specifically, the presence of moDC2 correlated with expanding tumor-infiltrating lymphocytes (TIL) in the anti-PD-1 treated MC38 mouse model, and scRNA-seq of human melanoma treated with anti-PD-1 confirmed a similar finding of responding tumors enriched for moDCs and increased TIL cytotoxicity. The gene discussed is PDCD1; the disease is melanoma.