Identification of CD318, TSPAN8 and CD66c as target candidates for CAR T cell based immunotherapy of pancreatic adenocarcinoma

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.

Multiplex Quantitative Analysis of Tumor-Infiltrating Lymphocytes, Cancer-Associated Fibroblasts, and CD200 in Pancreatic Cancer

“…In pancreatic cancer, CD8-positive cytotoxic T cells are associated with better prognosis [ 33 , 34 ]. A variety of therapies have been tested to increase CD8 T cell infiltration into the stroma of PDAC, including chimeric antigen receptor T cell therapies, CD40 antibody blockade, and CCL2/CCR2 blockade [ 35 , 36 , 37 , 38 ]. Additionally, depletion of immunosuppressive cells in the tumor microenvironment of PDAC including T regulatory cells, tumor-associated dendritic cells, and MDSCs have been shown to increase CD8 cell infiltration [ 39 , 40 ].…”

MACSima imaging cyclic staining (MICS) technology reveals combinatorial target pairs for CAR T cell treatment of solid tumors

“…After re-analyzing the co-expression of these markers, we concluded that an AND gated target combination of CDCP1 with TSPAN8 or CEACAM6 could be promising from a safety perspective of a CAR T cell therapy (Fig. 6 ), while development of CLA-specific CAR T cells requires further technical solutions as it is expressed on activated CAR T cells 17 .…”

“…Using a similar approach as described above, we previously reported the analysis of PDAC 17 . There we identified CDCP1 (CD318), tetraspanin-8 (TSPAN8), cutaneous lymphocyte-associated antigen (CLA) and CEACAM6 (CD66c) as target candidates for CAR T cell-based immunotherapy.…”

MACSima Imaging Cyclic Staining (MICS) Technology Reveals Combinatorial Target Pairs for CAR T Treatment of Solid Tumors

“…After re-analyzing the co-expression of these markers, we concluded that an AND gated target combination of CDCP1 with TSPAN8 or CEACAM6 could be promising from a safety perspective of a CAR T cell therapy (Fig. 6), while development of CLA speci c CAR T cells requires further technical solutions as it is expressed on activated CAR T cells 17 . Finally, we applied our screening approach to HGSOC.…”

“…Using a similar approach as described above, we previously reported the analysis of PDAC 17 . There, we identi ed CDCP1 (CD318), tetraspanin-8 (TSPAN8), cutaneous lymphocyte-associated antigen (CLA) and CECAM6 (CD66c) as target candidates for CAR T cell based immunotherapy.…”