CD274 and neoplasm: A microfluidics‐enabled nanovesicle using ultra‐pH‐sensitive polymer mannose‐poly(carboxybetaine methacrylate)‐poly(hydroxyethyl piperidine methacrylate) (Man‐PCB‐PHEP) is developed to deliver CD47/PD‐L1 antibodies (NCPA) for tumor‐acidity‐activated immunotherapy.