CD4 and melanoma: In our study, we calculated the relative proportion of 22 types of immune cells based on the CIBERSORT algorithm and the results revealed that melanoma samples with high IRGPI harbored more infiltration of CD8+ T cells, activated memory CD4+ T cells, naive B cells, and NK cells, which further elucidated the reason why IRGPI-high patients with melanoma can benefit from ICI therapy.