Targeting glycosylation of PD-1 to enhance CAR-T cell cytotoxicity

J Hematol Oncol. 2019 Nov 29;12(1):127. doi: 10.1186/s13045-019-0831-5.

Abstract

Asparagine-linked (N-linked) glycosylation is ubiquitous and can stabilize immune inhibitory PD-1 protein. Reducing N-linked glycosylation of PD-1 may decrease PD-1 expression and relieve its inhibitory effects on CAR-T cells. Considering that the codon of Asparagine is aac or aat, we wondered if the adenine base editor (ABE), which induces a·t to g·c conversion at specific site, could be used to reduce PD-1 suppression by changing the glycosylated residue in CAR-T cells. Our results showed ABE editing altered the coding sequence of N74 residue of PDCD1 and downregulated PD-1 expression in CAR-T cells. Further analysis showed ABE-edited CAR-T cells had enhanced cytotoxic functions in vitro and in vivo. Our study suggested that the single base editors can be used to augment CAR-T cell therapy.

Keywords: CAR-T cell; Glycosylation; PD-1; Single base editing.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / chemistry*
  • Adenine / metabolism
  • Animals
  • Cytotoxicity, Immunologic
  • Glycosylation
  • Humans
  • Immunotherapy, Adoptive / methods*
  • Lymphocyte Activation
  • Mice
  • Neoplasms / immunology
  • Neoplasms / metabolism
  • Neoplasms / therapy*
  • Programmed Cell Death 1 Receptor / chemistry
  • Programmed Cell Death 1 Receptor / immunology*
  • Programmed Cell Death 1 Receptor / metabolism
  • Receptors, Chimeric Antigen / immunology*
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / transplantation
  • Tumor Cells, Cultured

Substances

  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor
  • Receptors, Chimeric Antigen
  • Adenine