Recruiting cytotoxic T cells to folate-receptor-positive cancer cells

Angew Chem Int Ed Engl. 2013 Nov 11;52(46):12101-12104. doi: 10.1002/anie.201306866. Epub 2013 Sep 25.

Abstract

Herein, we describe the synthesis of a chemically defined anti-CD3 Fab-folate conjugate that targets cytotoxic T cells to folate receptor positive (FR+) tumors. The unnatural amino acid pacetylphenylalanine (pAcPhe) was site-specifically incorporated into an anti-CD3 Fab and conjugated to folate via the formation of a stable oxime linkage. The anti-CD3 Fab-folate conjugate was able to promote T cell mediated killing of FR+ cancer cells in culture. Moreover, the anti-CD3 Fab-folate conjugate potently eliminates tumor xenografts in mice. This approach can likely be generalized to other ligands that bind cancer and other pathogenic cells.

Keywords: T cells; bispecific antibody; cancer; folate receptor; immunotherapy.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • CD3 Complex / immunology
  • Cell Line, Tumor
  • Coculture Techniques
  • Folate Receptors, GPI-Anchored / metabolism*
  • Folic Acid / chemistry
  • Humans
  • Immunoglobulin Fab Fragments / chemistry
  • Immunoglobulin Fab Fragments / immunology
  • Immunoglobulin Fc Fragments / chemistry
  • Immunoglobulin Fc Fragments / immunology
  • Immunoglobulin G / chemistry
  • Immunoglobulin G / immunology
  • Immunotherapy
  • Leukocytes, Mononuclear / cytology
  • Male
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • Neoplasms / metabolism
  • Neoplasms / pathology
  • Neoplasms / therapy
  • Rats
  • Rats, Sprague-Dawley
  • T-Lymphocytes, Cytotoxic / cytology
  • T-Lymphocytes, Cytotoxic / immunology*

Substances

  • CD3 Complex
  • Folate Receptors, GPI-Anchored
  • Immunoglobulin Fab Fragments
  • Immunoglobulin Fc Fragments
  • Immunoglobulin G
  • immunoglobulin Facb fragment
  • Folic Acid