Robert et al. (Alspach et al. 2019) found in mice sarcoma model that ICB therapy sensitivity depends on the combination of CD4+ and CD8+T cells, predicting that even tumor patients with immunogenic MHC-I neo-antigens may not respond to immunotherapy due to the absence of immunogenic MHC-II-restricted CD4+T cell antigens. The gene discussed is CD4; the disease is neoplasm.