Double knockout pigs deficient in N-glycolylneuraminic acid and galactose α-1,3-galactose reduce the humoral barrier to xenotransplantation

Xenotransplantation. Jan-Feb 2013;20(1):27-35. doi: 10.1111/xen.12019.


Background: Clinical xenotransplantation is not possible because humans possess antibodies that recognize antigens on the surface of pig cells. Galα-1,3-Gal (Gal) and N-glycolylneuraminic acid (Neu5Gc) are two known xenoantigens.

Methods: We report the homozygous disruption of the α1, 3-galactosyltransferase (GGTA1) and the cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH) genes in liver-derived female pig cells using zinc-finger nucleases (ZFNs). Somatic cell nuclear transfer (SCNT) was used to produce healthy cloned piglets from the genetically modified liver cells. Antibody-binding and antibody-mediated complement-dependent cytotoxicity assays were used to examine the immunoreactivity of pig cells deficient in Neu5Gc and Gal.

Results: This approach enabled rapid production of a pig strain deficient in multiple genes without extensive breeding protocols. Immune recognition studies showed that pigs lacking both CMAH and GGTA1 gene activities reduce the humoral barrier to xenotransplantation, further than pigs lacking only GGTA1.

Conclusions: This technology will accelerate the development of pigs for xenotransplantation research.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Heterophile / metabolism
  • Antibody-Dependent Cell Cytotoxicity
  • Antigens, Heterophile / immunology
  • Antigens, Heterophile / metabolism
  • Base Sequence
  • Cells, Cultured
  • DNA / genetics
  • Disaccharides / deficiency
  • Disaccharides / immunology*
  • Female
  • Galactosyltransferases / deficiency
  • Galactosyltransferases / genetics
  • Gene Knockout Techniques / methods
  • Humans
  • Leukocytes, Mononuclear / immunology
  • Mixed Function Oxygenases / deficiency
  • Mixed Function Oxygenases / genetics
  • Neuraminic Acids / immunology*
  • Neuraminic Acids / metabolism
  • Sus scrofa / genetics*
  • Sus scrofa / immunology*
  • Sus scrofa / metabolism
  • Transplantation, Heterologous / immunology*


  • Antibodies, Heterophile
  • Antigens, Heterophile
  • Disaccharides
  • Neuraminic Acids
  • N-glycolylneuraminic acid
  • galactosyl-(1-3)galactose
  • DNA
  • Mixed Function Oxygenases
  • CMPacetylneuraminate monooxygenase
  • Galactosyltransferases
  • alpha-1,3-galactosyltransferase 1, porcine