Identification of alpha-Gal and non-Gal epitopes in pig corneal endothelial cells and keratocytes by using mass spectrometry.
OBJECTIVE
To investigate the expression of alpha-Gal or unidentified non-Gal antigens in pig corneal endothelial cells and keratocytes, we performed the qualitative and quantitative analysis by using mass spectrometry.


METHODS
The N-glycans from common adult pig corneal endothelial cells and keratocytes cultured in vitro were directly analyzed by using mass spectrometric approaches. In addition, immunochemical staining was added to confirm the non-Gal antigen expression in pig corneal cells.


RESULTS
Totally, 34 of the sialylated N-glycans from pig corneal endothelial cells and 27 from pig keratocytes were identified and observed to contain nonhuman sialic acid, NeuGc as well as NeuAc. In addition, we were able to detect 25 of alpha-galactosylated N-glycan structures (22.2% of total) from the pig corneal endothelial cells and 18 of that (17.5% of total) from the pig keratocytes by using mass spectrometric approaches. On immunofluorescent staining, the expression of sialylated glycans was also observed.


CONCLUSIONS
As well as alpha-Gal epitopes, several promising non-Gal antigens were widely expressed on both pig corneal endothelial cells and keratocytes. The detailed structural information of the alpha-Gal and non-Gal epitopes would be a tremendous value to develop a new strategy for the successful corneal xenotransplantation in future.
Kim
Yun-Gon
YG
Institute of Molecular Biology and Genetics and Institute of Bioengineering, Seoul National University, Seoul, Korea.
Oh
Joo Youn
JY
Gil
Geun-Cheol
GC
Kim
Mee Kum
MK
Ko
Jung Hwa
JH
Lee
Sukmook
S
Lee
Hyun Ju
HJ
Wee
Won Ryang
WR
Kim
Byung-Gee
BG
D000818:Animals; D018929:Cell Culture Techniques; D016039:Corneal Transplantation; D004728:Endothelium, Corneal / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D000939:Epitopes / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D019158:N-Acetylneuraminic Acid / Q000737:chemistry / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013552:Swine; D014183:Transplantation, Heterologous; D000519:alpha-Galactosidase / Q000378:metabolism*
D000939:Epitopes; D011134:Polysaccharides; D000519:alpha-Galactosidase; D019158:N-Acetylneuraminic Acid