Highly sensitive cell-based assay system to monitor the sialyl Lewis X biosynthesis mediated by alpha1-3 fucosyltransferase-VII.
The sialyl Lewis X (sLe(x)) determinant on leukocytes serves as a ligand for selectin family cell adhesion molecules, and selectin-carbohydrate interaction is considered to play an important role in the process of leukocyte extravasation during inflammation. Among several alpha1-3 fucosyltransferases (FucTs), FucT-VII plays a critical role in the biosynthesis of sLe(x)-epitopes. Therefore, small molecules specifically designed to inhibit the FucT-VII enzyme may have potential as anti-inflammatory agents. Here, we have developed a versatile cell-based assay system to monitor sLe(x) biosynthesis using the GeneSwitch System. This system is a mifepristone (MFP)-inducible mammalian expression system, and human transfectant T lymphoblasts expressed the mRNA of FucT-VII and the sLe(x)-epitopes on the cell surface in a time-dependent manner in the presence of MFP, with very low background transcription. Furthermore, when the transfectants were treated with the FucT-VII inhibitor panosialin, sLe(x) expression on the induced cells was inhibited dose dependently without alteration at the mRNA level of FucT-VII. These results suggest that the FucT-VII may be a major regulator of the biosynthesis of the sLe(x)-epitopes on T lymphoblasts, and this cell-based assay may be utilized for a screening system of FucT-VII inhibitors.
Pharmacology Research Laboratories, Tanabe Seiyaku Co., Ltd., 16-89 Kashima 3-chome, Yodogawa-ku, Osaka 532-8505, Japan.
Masahiko
M
Miyashiro
Sachiko
S
Furuya
Kotomi
K
Fujishige
Takahisa
T
Sugita
D000818:Animals; D001555:Benzene Derivatives / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D000939:Epitopes; D005647:Fucosyltransferases / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D015735:Mifepristone / Q000494:pharmacology; D009844:Oligosaccharides / Q000096:biosynthesis* / Q000235:genetics; D000080506:Sialyl Lewis X Antigen; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000502:physiology; D019076:Transgenes
D001555:Benzene Derivatives; D000939:Epitopes; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; C003039:panosialin; D015735:Mifepristone; D005647:Fucosyltransferases; C031692:galactoside 3-fucosyltransferase