Retargeting NK92 cells using an HLA-A2-restricted, EBNA3C-specific chimeric antigen receptor

Cancer Gene Ther. 2012 Feb;19(2):84-100. doi: 10.1038/cgt.2011.66. Epub 2011 Oct 7.

Abstract

Advances in adoptive cell immunotherapy have led to several promising options for cancer patients. Single-chain variable fragments (scFvs) were isolated from a human phage display library by panning on recombinant human leukocyte antigen (HLA)-A2-peptide complexes. A scFv (EBNA Clone 315) specific for HLA-A2 carrying a 10 amino acid peptide (LLDFVRFMGV) derived from the Epstein-Barr virus latent protein EBNA3C was fully characterized. EBNA Clone 315 displayed exquisite specificity toward its targeted T-cell epitope (TCE) and did not cross-react with the free peptide, HLA-A2 complexes, which carried irrelevant peptides, or HLA-A2(-) cells. Furthermore, after engineering into a scFv-Fc fusion protein, we were able to determine its affinity, detection sensitivity, and ability to induce antibody-dependent cellular cytotoxicity (ADCC). As a proof-of-principle, a chimeric antigen receptor (CAR) version of EBNA Clone 315 was used to reprogram NK92MI cells. CAR-expressing NK92MI cells showed highly specific and potent cytotoxicity toward the targeted TCE, with detection sensitivity of approximately 25 molecules and cytolytic capacity threefold greater than scFv-Fc-mediated ADCC. For the first time, we show the successful reprogramming of non-T cells toward a specific TCE using a CAR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Viral / immunology*
  • CHO Cells
  • Cell Line
  • Chimerism
  • Cricetinae
  • Epitopes, T-Lymphocyte / immunology
  • Epstein-Barr Virus Nuclear Antigens
  • HLA-A2 Antigen / genetics
  • HLA-A2 Antigen / immunology*
  • Humans
  • Immunoglobulin Fragments / immunology
  • Killer Cells, Natural / immunology*
  • Oligopeptides / immunology*
  • Oligopeptides / metabolism
  • Receptors, Antigen / genetics
  • Receptors, Antigen / immunology*

Substances

  • Antigens, Viral
  • EBNA-3C, epstein-barr virus
  • Epitopes, T-Lymphocyte
  • Epstein-Barr Virus Nuclear Antigens
  • HLA-A2 Antigen
  • Immunoglobulin Fragments
  • Oligopeptides
  • Receptors, Antigen