GITR domain inside CAR co-stimulates activity of CAR-T cells against cancer

Front Biosci (Landmark Ed). 2018 Jun 1;23:2245-2254.

Abstract

T cells expressing Chimeric antigen receptors or CAR-T cells are used as a novel treatment against hematological and solid cancers. In this report, we designed CAR with glucocorticoid-induced TNFR-related protein (GITR) co-stimulatory domain to study its ability to co-activate CAR-T cells. EGFR-GITR-CD3 CAR-T cells were cytotoxic against EGFR-positive: pancreatic and ovarian cancer cells but not against EGFR-negative cancer cells. The cytotoxic activity of EGFR-GITR-CD3 CAR-T cells was comparable or better than EGFR-28-CD3 or EGFR-41BB-CD3 CAR-T cells. We designed also EGFR-CD3-GITR-CAR and EGFR-ΔGITR-CD3 with deleted 184-192 amino-acids of co-stimulatory GITR domain, and showed that EGFR-GITR-CD3 had significantly higher cytotoxic activity against EGFR-positive cells. The EGFR-GITR-CD3 cells secreted significantly higher levels of IFN-gamma than EGFR-CD3-GITR and EGFR-ΔGITR-CD3 cells. In addition, Mesothelin-GITR-CD3 CAR-T cells also killed mesothelin-positive ovarian cancer cell lines, and pancreatic cancer cells. Moreover, CD19-GITR-CD3 CAR-T cells had significant cytotoxic activity against CD19-positive cancer cells in vitro and in Raji xenograft tumors in vivo. Thus, our results clearly show that GITR co-stimulatory domain can be used as a novel co-stimulatory domain in CAR-T cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD19 / genetics
  • Antigens, CD19 / immunology
  • Antigens, CD19 / metabolism
  • CD3 Complex / genetics
  • CD3 Complex / immunology
  • CD3 Complex / metabolism
  • Cell Line, Tumor
  • Cytotoxicity, Immunologic / immunology*
  • Glucocorticoid-Induced TNFR-Related Protein / genetics
  • Glucocorticoid-Induced TNFR-Related Protein / immunology*
  • Glucocorticoid-Induced TNFR-Related Protein / metabolism
  • HEK293 Cells
  • Humans
  • MCF-7 Cells
  • Male
  • Mice, Inbred NOD
  • Mice, Knockout
  • Mice, SCID
  • Neoplasms / immunology*
  • Neoplasms / pathology
  • Receptors, Chimeric Antigen / genetics
  • Receptors, Chimeric Antigen / immunology*
  • Receptors, Chimeric Antigen / metabolism
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • Xenograft Model Antitumor Assays / methods*

Substances

  • Antigens, CD19
  • CD3 Complex
  • Glucocorticoid-Induced TNFR-Related Protein
  • Receptors, Chimeric Antigen
  • TNFRSF18 protein, human