Abstract
A major roadblock prohibiting effective cellular immunotherapy of pancreatic ductal adenocarcinoma (PDAC) is the lack of suitable tumor-specific antigens. To address this challenge, here we combine flow cytometry screenings, bioinformatic expression analyses and a cyclic immunofluorescence platform. We identify CLA, CD66c, CD318 and TSPAN8 as target candidates among 371 antigens and generate 32 CARs specific for these molecules. CAR T cell activity is evaluated in vitro based on target cell lysis, T cell activation and cytokine release. Promising constructs are evaluated in vivo. CAR T cells specific for CD66c, CD318 and TSPAN8 demonstrate efficacies ranging from stabilized disease to complete tumor eradication with CD318 followed by TSPAN8 being the most promising candidates for clinical translation based on functionality and predicted safety profiles. This study reveals potential target candidates for CAR T cell based immunotherapy of PDAC together with a functional set of CAR constructs specific for these molecules.
Highlights
A major roadblock prohibiting effective cellular immunotherapy of pancreatic ductal adenocarcinoma (PDAC) is the lack of suitable tumor-specific antigens
We used antibodies specific for these 105 antigens and measured their expression on two additional representative patient-derived xenograft (PDX) models followed by a manual exclusion of non-suitable target candidates, such as HLA molecules which were present in the pre-set screening plates
This is, in two ways, an interesting finding: (1) it was never described before to be expressed on pancreatic cancer cells and (2) was so far only reported to be expressed on subsets of certain cell types, which could mean no essential tissues may be harmed when targeted by chimeric antigen receptor (CAR) T cells
Summary
A major roadblock prohibiting effective cellular immunotherapy of pancreatic ductal adenocarcinoma (PDAC) is the lack of suitable tumor-specific antigens. We examine the expression of a multitude of these target candidates within the primary pancreatic cancer tissues from patients using a cyclic immunofluorescence (IF) imaging platform This technique enables to survey expression profiles of several dozens of antigens on the very same tissue section. We verify these results using flow cytometry on seven additional primary PDACs as well as on three metastatic lesions Based on these results, we design 32 CARs specific for the four most promising target candidates, CLA, CD66c, TSPAN8, and CD318 with varying spacer lengths and scFv orientations. CAR constructs that perform best in vitro are examined in two independent preclinical mouse xenograft models and evaluated for their expression on healthy tissues by cyclic immune fluorescence and flow cytometry resulting in promising candidates for future clinical trials
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
