The biologically functional identification of a novel TIM3-binding peptide P26 in vitro and in vivo

Cancer Chemother Pharmacol. 2020 Dec;86(6):783-792. doi: 10.1007/s00280-020-04167-0. Epub 2020 Oct 21.

Abstract

Purpose: Recent studies have shown that TIM3 plays an important role in T-cell failure, which is closely related to the resistance to anti-programmed cell death protein 1 (PD-1) treatment. However, there have been no reports on the application of peptide blockers to TIM3. In this study, we endeavored to identify the in vitro and in vivo anti-tumor activities of a TIM3-targeting peptide screened from the phage peptide library.

Methods: Phage display peptide library technology, surface plasmon resonance, flow cytometry, and mixed lymphocyte reaction were utilized to screen and demonstrate the bioactivities of P26, a TIM3-targeting peptide. Meanwhile, tumor growth assay was performed to evaluate the anti-tumor effect of P26.

Results: In terms of affinity, we demonstrated that P26 specifically binds to TIM3 at the cellular and molecular levels, which therefore blocks the interaction between TIM3 and Galectin-9 (Gal-9) and competes with Gal-9 to bind TIM3. Additionally, P26 significantly increases T-cell activity and elevates IFN-γ and IL-2 levels in a dose-dependent manner. Notably, P26 also counteracts Gal-9-mediated T-cell suppression. More importantly, P26 can inhibit growth of MC38-hPD-L1 tumor in mice.

Conclusions: P26, as a novel TIM3-binding peptide, has the ideal bioactivity connecting to TIM3 and the potential prospect of application in immunotherapy as an alternative or adjuvant to existing agents.

Keywords: Anti-tumor; Biological activity; P26; Phage display peptide library; TIM3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Combined Chemotherapy Protocols / pharmacology*
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Cell Line, Tumor / transplantation
  • Disease Models, Animal
  • Drug Resistance, Neoplasm / drug effects*
  • Drug Screening Assays, Antitumor
  • Female
  • Galectins / metabolism
  • HEK293 Cells
  • Hepatitis A Virus Cellular Receptor 2 / antagonists & inhibitors*
  • Hepatitis A Virus Cellular Receptor 2 / genetics
  • Hepatitis A Virus Cellular Receptor 2 / metabolism
  • Humans
  • Immune Checkpoint Inhibitors / pharmacology
  • Immune Checkpoint Inhibitors / therapeutic use
  • Lymphocyte Activation / drug effects
  • Mice
  • Mice, Transgenic
  • Neoplasms / drug therapy*
  • Neoplasms / immunology
  • Neoplasms / pathology
  • Peptide Library
  • Programmed Cell Death 1 Receptor / antagonists & inhibitors
  • Programmed Cell Death 1 Receptor / immunology
  • Protein Binding / drug effects
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism

Substances

  • Galectins
  • HAVCR2 protein, human
  • Hepatitis A Virus Cellular Receptor 2
  • Immune Checkpoint Inhibitors
  • LGALS9 protein, human
  • PDCD1 protein, human
  • Peptide Library
  • Programmed Cell Death 1 Receptor