title: GUCY2C-directed CAR-T cells oppose colorectal cancer metastases without autoimmunity.
abstract: Adoptive T-cell therapy (ACT) is an emerging paradigm in which T cells are genetically modified to target cancer-associated antigens and eradicate tumors. However, challenges treating epithelial cancers with ACT reflect antigen targets that are not tumor-specific, permitting immune damage to normal tissues, and preclinical testing in artificial xenogeneic models, preventing prediction of toxicities in patients. In that context, mucosa-restricted antigens expressed by cancers exploit anatomical compartmentalization which shields mucosae from systemic antitumor immunity. This shielding may be amplified with ACT platforms employing antibody-based chimeric antigen receptors (CARs), which mediate MHC-independent recog-nition of antigens. GUCY2C is a cancer mucosa antigen expressed on the luminal surfaces of the intestinal mucosa in mice and humans, and universally overexpressed by colorectal tumors, suggesting its unique utility as an ACT target. T cells expressing CARs directed by a GUCY2C-specific antibody fragment recognized GUCY2C, quantified by expression of activation markers and cytokines. Further, GUCY2C CAR-T cells lysed GUCY2C-expressing, but not GUCY2C-deficient, mouse colorectal cancer cells. Moreover, GUCY2C CAR-T cells reduced tumor number and morbidity and improved survival in mice harboring GUCY2C-expressing colorectal cancer metastases. GUCY2C-directed T cell efficacy reflected CAR affinity and surface expression and was achieved without immune-mediated damage to normal tissues in syngeneic mice. These observations highlight the potential for therapeutic translation of GUCY2C-directed CAR-T cells to treat metastatic tumors, without collateral autoimmunity, in patients with metastatic colorectal cancer.
authors.affiliation: Bluebird Bio, Seattle, Cambridge, MA, USA; Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Magee
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University , Philadelphia, PA, USA.
authors.forename: Crystal L
authors.initials: CL
authors.lastname: Kraft
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University , Philadelphia, PA, USA.
authors.forename: Tara S
authors.initials: TS
authors.lastname: Abraham
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University , Philadelphia, PA, USA.
authors.forename: Trevor R
authors.initials: TR
authors.lastname: Baybutt
authors.affiliation: School of Biomedical Engineering, Science & Health Systems, Drexel University , Philadelphia, PA, USA.
authors.forename: Glen P
authors.initials: GP
authors.lastname: Marszalowicz
authors.affiliation: Department of Pathology, Stanford University School of Medicine , Stanford, CA, USA.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University , Philadelphia, PA, USA.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Waldman
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University , Philadelphia, PA, USA.
authors.forename: Adam E
authors.identifier: 0000-0001-9216-4560
authors.initials: AE
authors.lastname: Snook
keywords: Adoptive immunotherapy; chimeric antigen receptors; colorectal cancer; gene therapy; guanylyl cyclase C