PDCD1 and pancreatic ductal adenocarcinoma: In another phase I clinical trial with six pancreatic ductal adenocarcinoma patients, CARTmeso cell treatment resulted in an elevated level of circulating antibodies produced against protumor-related proteins such as B cell maturation antigen, Ras-related protein Rab-11B, signal-transducing adaptor protein 1, programmed cell death protein 1 (PD1), programmed death ligand 1 (PDL1), and transducin-like enhancer protein 3 in one patient [51].