TY - JOUR
T1 - Glycosphingolipids in vascular endothelial cells
T2 - Relationship of heterogeneity in Gb3Cer/CD77 receptor expression with differential Shiga toxin 1 cytotoxicity
AU - Schweppe, Christian H.
AU - Bielaszewska, Martina
AU - Pohlentz, Gottfried
AU - Friedrich, Alexander W.
AU - Büntemeyer, Heino
AU - Alexander Schmidt, M.
AU - Kim, Kwang S.
AU - Peter-Katalinić, Jasna
AU - Karch, Helge
AU - Müthing, Johannes
N1 - Funding Information:
Acknowledgements This work was supported by grants from the Deutsche Forschungsgemeinschaft (DFG), program “Infections of the Endothelium” SPP 1130 project KA 717/4-2 (H.K.), the SFB 629 (B2, M.A.S.), the cooperative projects FR2569/1-1 (A.W.F.) and MU845/4-1 (J.M.) and a grant from the Interdisciplinary Center of Clinical Research (IZKF) Münster, project no. Ka2/061/04 (H.K.).
PY - 2008/5
Y1 - 2008/5
N2 - Shiga toxin (Stx) 1 binds to the glycosphingolipid (GSL) globotriaosylceramide (Gb3Cer/CD77) and injures human endothelial cells. In order to gain insight into Stx1-induced cellular impairment, we analysed in detail the molecular heterogeneity of Stx1 receptors in two endothelial cell lines differing in their Stx1-sensitivity. We observed a moderate sensitivity to Stx1 of human brain microvascular endothelial cells (HBMECs, CD 50>200 ng/ml), but a considerably higher mortality rate in cultures of EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (CD50 of 0.2 ng/ml). Immunofluorescence microscopy demonstrated the presence of Gb3Cer in both cell lines, but showed an enhanced content of Gb3Cer in EA.hy 926 cells. Solid phase overlay binding assays of isolated GSLs combined with nanoelectrospray ionization quadrupole time-of-flight mass spectrometry demonstrated a balanced proportion of Gb3Cer and globotetraosylceramide (Gb4Cer) in HBMECs, but an increase of Gb3Cer and absence of Gb4Cer in EA.hy 926 cells. Gb3Cer species with C24:1/C24:0 fatty acids were found to dominate over those with C16:0 fatty acids in EA.hy 926 cells, but were similarly distributed in HBMECs. Reverse transcriptase polymerase chain reaction indicated the concomitant presence of Gb3Cer and Gb4Cer synthases in HBMECs, whereas EA.hy 926 cells expressed Gb3Cer synthase, but completely lacked Gb4Cer synthase. This deficiency, resulting in the accumulation of Gb3Cer in EA.hy 926 cells, represents the most prominent molecular reason that underlies the different Stx1 sensitivities of HBMECs and EA.hy 926 endothelial cells.
AB - Shiga toxin (Stx) 1 binds to the glycosphingolipid (GSL) globotriaosylceramide (Gb3Cer/CD77) and injures human endothelial cells. In order to gain insight into Stx1-induced cellular impairment, we analysed in detail the molecular heterogeneity of Stx1 receptors in two endothelial cell lines differing in their Stx1-sensitivity. We observed a moderate sensitivity to Stx1 of human brain microvascular endothelial cells (HBMECs, CD 50>200 ng/ml), but a considerably higher mortality rate in cultures of EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (CD50 of 0.2 ng/ml). Immunofluorescence microscopy demonstrated the presence of Gb3Cer in both cell lines, but showed an enhanced content of Gb3Cer in EA.hy 926 cells. Solid phase overlay binding assays of isolated GSLs combined with nanoelectrospray ionization quadrupole time-of-flight mass spectrometry demonstrated a balanced proportion of Gb3Cer and globotetraosylceramide (Gb4Cer) in HBMECs, but an increase of Gb3Cer and absence of Gb4Cer in EA.hy 926 cells. Gb3Cer species with C24:1/C24:0 fatty acids were found to dominate over those with C16:0 fatty acids in EA.hy 926 cells, but were similarly distributed in HBMECs. Reverse transcriptase polymerase chain reaction indicated the concomitant presence of Gb3Cer and Gb4Cer synthases in HBMECs, whereas EA.hy 926 cells expressed Gb3Cer synthase, but completely lacked Gb4Cer synthase. This deficiency, resulting in the accumulation of Gb3Cer in EA.hy 926 cells, represents the most prominent molecular reason that underlies the different Stx1 sensitivities of HBMECs and EA.hy 926 endothelial cells.
KW - EA.hy 926 cells
KW - Glycolipids
KW - Glycosyltransferases
KW - HBMECs
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UR - http://www.scopus.com/inward/citedby.url?scp=41149089223&partnerID=8YFLogxK
U2 - 10.1007/s10719-007-9091-7
DO - 10.1007/s10719-007-9091-7
M3 - Article
C2 - 18176841
AN - SCOPUS:41149089223
SN - 0282-0080
VL - 25
SP - 291
EP - 304
JO - Glycoconjugate Journal
JF - Glycoconjugate Journal
IS - 4
ER -