Regulation of natural killer cell-mediated swine endothelial cell lysis through genetic remodeling of a glycoantigen.
The effect of remodeling of a glycoantigen such as the alpha-Gal epitope, Galalpha1,3Galbeta1,4GlcNAc-R, by the introduction of glycosyltransferase genes on natural killer (NK) cell-mediated direct cytotoxicity was investigated using human peripheral blood mononuclear cells (PBMC) or an NK-like cell line, YT cells, as an effector, and swine endothelial cells (SEC) as a target. Several SEC transfectants were established by transfection with the genes for beta1,4-N-acetylglucosaminyltransferase III, alpha2, 3-sialyltransferase and alpha1,2-fucosyltransferase. These transfections led to dramatic reductions in both direct and indirect NK cell-mediated cytotoxicity, by 72-94% in the case of PBMC and 27-72% in that of YT cells, in addition to an effective reduction in xenoantigenicity, which is substantially caused by the alpha-Gal epitope, to human natural antibodies. The NK cell-mediated direct cytotoxicity was remarkably blocked by an anti-alpha-Gal epitope monoclonal antibody or GSI lectin which preferentially binds to the epitope. Furthermore, treatment of the parental cells with alpha-galactosidase resulted in a significant reduction in cytotoxicity. These results suggest that the alpha-Gal epitope is involved not only in hyperacute rejection and acute vascular rejection, but also in NK cell-mediated direct cytotoxicity. Thus, the genetic remodeling of the alpha-Gal epitope and probably other glycoantigens as well can be expected to represent a new approach for overcoming not only indirect but also direct immunity to xenografts.
Miyagawa
S
S
Division of Organ Transplantation, Biomedical Research Center, Osaka University Graduate School of Medicine, Osaka University Medical School, Suita, Osaka, 565-0871, Japan. miyagawa@orgtrp.med.osaka-u ac.jp.
Nakai
R
R
Yamada
M
M
Tanemura
M
M
Ikeda
Y
Y
Taniguchi
N
N
Shirakura
R
R
D000818:Animals; D004727:Endothelium / Q000276:immunology*; D005434:Flow Cytometry; D016695:Glycosyltransferases / Q000235:genetics / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D037102:Lectins / Q000276:immunology; D051379:Mice; D037121:Plant Lectins; D013552:Swine; D014162:Transfection; D000519:alpha-Galactosidase / Q000378:metabolism
C045475:Griffonia simplicifolia lectins; D037102:Lectins; D037121:Plant Lectins; D016695:Glycosyltransferases; D000519:alpha-Galactosidase