First, we established a local inhibitory checkpoint monoclonal antibody (LicMAb) by fusing two N-terminal extracellular domains of SIRPα to a full-length anti-human mesothelin (MSLN)-IgG1 antibody, a well-described tumor-associated antigen in epithelial ovarian cancer (EOC) and pancreatic ductal adenocarcinoma (PDAC). Here, MSLN is linked to pancreatic ductal adenocarcinoma.