Structural analysis of alpha-Gal and new non-Gal carbohydrate epitopes from specific pathogen-free miniature pig kidney.
The major barrier in transplantation of pig organs into humans is the presence of surface carbohydrate antigens (e.g., the Gal alpha 1-3 Gal beta 1-4GlcNAc-R (alpha-Gal) epitope) expressed on pig endothelial cells. In this study, total N-glycans from membrane glycoproteins derived from specific pathogen-free miniature pig kidney are identified by MALDI-TOF, negative ion ESI MS/MS and normal-phase HPLC (NP-HPLC) combined with exoglycosidase digestion. Over 100 N-glycans, including sialylated and neutral types, were identified. As well as the known alpha-Gal antigens, some of these glycans contained novel non-Gal carbohydrate antigens such as (Neu5Gc-Gal-GlcNAc) and Gal alpha 1-3 Lewis(x) (Gal-Gal-(Fuc)GlcNAc) which have not been reported before in N-glycans from pig organs. The ability of MALDI, ESI, and HPLC to measure the relative proportions of the glycans was evaluated. The HPLC resolution was insufficient for accurate work and some minor differences were noted in the ionization efficiencies of different glycan groups when measured by the two mass spectrometric techniques. However, the results indicated that the relative quantity of alpha-Gal epitope was in the region of 50% of the complex glycans. High-mannose type glycans were also abundant (35-43%) but appeared to be ionized more efficiently than the complex glycans by ESI than by MALDI.
Kim
Yun-Gon
YG
Interdisciplinary Program for Biochemical Engineering and Biotechnology, Seoul National University, Seoul, Korea.
Gil
Geun-Cheol
GC
Harvey
David J
DJ
Kim
Byung-Gee
BG
D000818:Animals; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D000939:Epitopes / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D006023:Glycoproteins / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D007668:Kidney / Q000166:cytology / Q000201:enzymology*; D008565:Membrane Proteins / Q000032:analysis; D008745:Methylation; D008956:Models, Chemical; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009438:Neuraminic Acids / Q000032:analysis; D013047:Specific Pathogen-Free Organisms; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013552:Swine; D013556:Swine, Miniature; D000519:alpha-Galactosidase / Q000032:analysis* / Q000737:chemistry
D002241:Carbohydrates; D000939:Epitopes; D006023:Glycoproteins; D008565:Membrane Proteins; D009438:Neuraminic Acids; D000519:alpha-Galactosidase