Article Text

Download PDFPDF

256 Dual-targeted CAR T cells boost antitumor immunity against solid tumors
  1. Amanda Finck,
  2. Ziming Wang,
  3. Ugur Uslu,
  4. Sofia Castelli,
  5. Andrew Rech,
  6. Julianna Latini,
  7. Donna Gonzalez,
  8. Tong Da,
  9. Regina M Young and
  10. Carl H June
  1. University of Pennsylvania, Philadelphia, PA, USA
  • Journal for ImmunoTherapy of Cancer (JITC) preprint. The copyright holder for this preprint are the authors/funders, who have granted JITC permission to display the preprint. All rights reserved. No reuse allowed without permission.


Background Chimeric Antigen Receptor (CAR) T cell therapy has shown strong antitumor potency in the context of hematological malignancies. However, CAR T cells face multiple barriers in treating solid tumors, such as trafficking to the tumor and a failure to expand and persist in the periphery. While ideally solid tumor target expression is restricted to the tumor to prevent on-target off-tumor toxicity, this scenario provides no opportunity for antigen-driven CAR T cell expansion in the periphery which can be correlated with response. To address this issue and increase the expansion and persistence of solid tumor-directed CAR T cells, we sought to design a dual-targeted CAR T cell against CD19 and the solid tumor antigen, mesothelin (MSLN), in order to maintain peripheral MSLN CAR T cell fitness and increase the number of CAR T cells which traffic to the tumor.

Methods Leveraging the paradigm of CD19 CAR T cells, which target a dispensable cell population and have exhibited success and safety in the clinic, we developed and optimized a CD19 and MSLN directed CAR T cell. We first assessed our technology in immunocompetent C57BL/6 mice where we established two syngeneic flank tumor models of pancreatic ductal adenocarcinoma (PDA) from KPC (KrasLSL.G12D/+p53R172H/+) mice, ranging in immunogenicity. In addition to assessing their antitumor efficacy, we also assessed their trafficking patterns compared to control CAR T cells. To determine the antitumor efficacy of human CAR T cells in NOD scid gamma (NSG) mice, we have developed a novel model to mimic CD19+ B cells in the periphery.

Results We have demonstrated specific cognate expansion of CD45.1+ dual murine CAR T cells and the induction of B cell aplasia in CD45.2+ C57BL/6 mice. Ultimately, we find enhanced B cell driven expansion in the blood, increased antitumor efficacy, and higher levels of early activation without increasing downstream exhaustion or toxicity compared to single CAR T cells. We have also identified alternative mechanisms of trafficking, likely owing to boosting in the spleen. Further, we have established a novel humanized model for CD19+ B cells in NSG mice and demonstrate that human dual CAR T cells expand in the periphery and demonstrate anti-tumor activity.

Conclusions Dual-targeted CAR T cells are a successful strategy to enhance solid tumor-directed expansion in the periphery and tumor infiltration resulting in increased antitumor efficacy in syngeneic and humanized models of PDA.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.