Recombinant lectin-like domain of thrombomodulin suppresses vascular inflammation by reducing leukocyte recruitment via interacting with Lewis Y on endothelial cells.
OBJECTIVE
The N-terminal lectin-like domain (domain 1 [D1]) of thrombomodulin (TM) is known to have an anti-inflammatory function. We previously showed that recombinant TM domain 1 (rTMD1) interacts with a carbohydrate molecule, Lewis Y (Le(y)), which is found to be expressed on adhesion molecules and involved in cell adhesion. Here, we tested the effect of rTMD1/Le(y) interaction on leukocyte recruitment in inflammation.


RESULTS
The expression of Le(y) on the surface of human umbilical vein endothelial cells was increased by tumor necrosis factor-α stimulation. Direct binding of rTMD1 to Le(y) on the cell surface was observed. rTMD1 inhibited Le(y)-mediated leukocyte adhesion on the Le(y)-immobilized flow chamber and activated endothelium under a shear flow. The following leukocyte transmigration to endothelium was also reduced by rTMD1 through binding Le(y). In vivo, treatment of rTMD1 reduced leukocyte recruitment to the inflammatory sites in carotid ligation injury and thioglycollate-induced peritonitis. rTMD1 administration in apolipoprotein E-deficient mice effectively suppressed atherosclerotic plaque formation and macrophage infiltration in atherosclerotic lesions. Increased Le(y) expression, as well as administered rTMD1, was observed in inflamed vessels.


CONCLUSIONS
rTMD1 suppresses vascular inflammation by inhibiting leukocyte recruitment to endothelium through attenuating Le(y)-mediated adhesion and further protects against atherosclerosis progression. The present study provides a mechanism showing that rTMD1 can inhibit inflammation by binding to its carbohydrate ligand Le(y).
From the Department of Biochemistry and Molecular Biology (W.-L.L., C.-S.S., G.-Y.S., H.-L.W.); Institute of Basic Medical Sciences (W.-L.L.); Cardiovascular Research Center (W.-L.L., G.-Y.S., H.-L.W.); Center of Bioscience and Biotechnology (H.-L.W.); and Department of Medical Laboratory Science and Biotechnology (C.-F.C.), College of Medicine, National Cheng Kung University, Tainan City, Taiwan.
Wei-Ling
WL
Lin
Chuan-Fa
CF
Chang
Chung-Sheng
CS
Shi
Guey-Yueh
GY
Shi
Hua-Lin
HL
Wu
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage* / Q000378:metabolism; D001057:Apolipoproteins E / Q000172:deficiency / Q000235:genetics; D050197:Atherosclerosis / Q000276:immunology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D020212:Carotid Artery Injuries / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D018920:Coculture Techniques; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D057809:HEK293 Cells; D061307:Human Umbilical Vein Endothelial Cells / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D007983:Lewis Blood Group Antigens / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D058226:Plaque, Atherosclerotic; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000008:administration & dosage; D018180:Thrombomodulin / Q000008:administration & dosage* / Q000378:metabolism; D057705:Transendothelial and Transepithelial Migration / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014657:Vasculitis / Q000276:immunology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*
D000893:Anti-Inflammatory Agents; D001057:Apolipoproteins E; D007983:Lewis Blood Group Antigens; C094162:Lewis Y antigen; D011994:Recombinant Proteins; C546931:THBD protein, human; D018180:Thrombomodulin; D014409:Tumor Necrosis Factor-alpha
Lewis Y antigen; atherosclerosis; inflammation; leukocytes; thrombomodulin