Genetic editing of HLA expression in hematopoietic stem cells to broaden their human application

Sci Rep. 2016 Feb 23:6:21757. doi: 10.1038/srep21757.

Abstract

Mismatch of human leukocyte antigens (HLA) adversely impacts the outcome of patients after allogeneic hematopoietic stem-cell transplantation (alloHSCT). This translates into the clinical requirement to timely identify suitable HLA-matched donors which in turn curtails the chances of recipients, especially those from a racial minority, to successfully undergo alloHSCT. We thus sought to broaden the existing pool of registered unrelated donors based on analysis that eliminating the expression of the HLA-A increases the chance for finding a donor matched at HLA-B, -C, and -DRB1 regardless of a patient's race. Elimination of HLA-A expression in HSC was achieved using artificial zinc finger nucleases designed to target HLA-A alleles. Significantly, these engineered HSCs maintain their ability to engraft and reconstitute hematopoiesis in immunocompromised mice. This introduced loss of HLA-A expression decreases the need to recruit large number of donors to match with potential recipients and has particular importance for patients whose HLA repertoire is under-represented in the current donor pool. Furthermore, the genetic engineering of stem cells provides a translational approach to HLA-match a limited number of third-party donors with a wide number of recipients.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alleles
  • Animals
  • Deoxyribonucleases / genetics*
  • Deoxyribonucleases / metabolism
  • Donor Selection / ethics
  • Gene Deletion*
  • Gene Expression
  • Genetic Engineering / methods
  • HLA-A Antigens / genetics*
  • HLA-A Antigens / immunology
  • HLA-B Antigens / genetics
  • HLA-B Antigens / immunology
  • HLA-C Antigens / genetics
  • HLA-C Antigens / immunology
  • HLA-DRB1 Chains / genetics
  • HLA-DRB1 Chains / immunology
  • Health Services Accessibility / ethics
  • Hematopoietic Stem Cell Transplantation / ethics
  • Hematopoietic Stem Cell Transplantation / ethnology*
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / immunology*
  • Histocompatibility Testing
  • Humans
  • Mice
  • Racial Groups
  • Transplantation, Heterologous
  • Transplantation, Homologous
  • Unrelated Donors
  • Zinc Fingers

Substances

  • HLA-A Antigens
  • HLA-B Antigens
  • HLA-C Antigens
  • HLA-DRB1 Chains
  • Deoxyribonucleases