The IFN-γ-producing capacity of CD4+ TILs directed against cancer neoepitopes may confer productive clinical responses, as shown in a patient with cholangiocarcinoma (directed against mutated ERBB2IP).13 Several other CD4+ T-cell neoantigens have been described and concisely reviewed elsewhere,35 a majority of which are restricted by the HLA-DR alleles. The gene discussed is CD4; the disease is cholangiocarcinoma.