Are N-glycolylneuraminic acid (Hanganutziu-Deicher) antigens important in pig-to-human xenotransplantation?
GROUND: N-glycolylneuraminic acid (NeuGc) epitopes, so called Hanganutziu-Deicher (HD) antigens, which are widely expressed on endothelial cells of all mammals except humans, are considered to be potential targets for natural and elicited anti-nonGalalpha1-3 Gal (Gal) antibodies in humans. We previously reported that anti-NeuGc antibodies were not detected in healthy humans by enzyme-linked immunosorbent assay (ELISA) using NeuGc-GM3-coated plates, and no antibody production was observed in patients with a history of exposure to pig cells. However, a recent paper has revealed that (i) anti-NeuGc antibodies to porcine red blood cells (PRBC) are detectable in most healthy humans, and (ii) the majority of anti-nonGal antibodies are specific for NeuGc epitopes. The purpose of this study was to reassess whether NeuGc is important as an immunogenic nonGal epitope. METHODS: The binding of antibodies to PRBC and porcine aortic endothelial cells (PAEC) was compared. Cells were treated with (i)