Other biomarkers predictive for response, survival and toxicity of ICI treatment have been investigated, including tumor tissue biomarkers (i.e. tumor mutational burden and MHC molecule expression), circulating immune cell biomarkers (i.e. CD4 + T-cells, myeloid-derived suppressor cells) and soluble systemic immune/inflammatory biomarkers (i.e. lactate dehydrogenase, C-reactive protein and cytokines). The gene discussed is CD4; the disease is neoplasm.