We next performed flow cytometry on paired pre- and posttreatment PBMCs from 14 patients with localized bladder cancer treated with neoadjuvant anti–PD-L1 before cystectomy on trial NCT02451423 to validate cytotoxic CD4+ T cells and their developmental and functional transitions with immunotherapy at the protein level. The gene discussed is CD4; the disease is urinary bladder carcinoma.