MADOIWA Seiji Jichi Medical School, School of Medicine, Division of Hemostasis and Thrombosis, 医学部, 助手 (70296119)
MIMURO Jun Jichi Medical School, School of Medicine, Division of Hemostasis and Thrombosis, 医学部, 講師 (10221607)
|Budget Amount *help
¥4,700,000 (Direct Cost : ¥4,700,000)
Fiscal Year 1998 : ¥4,700,000 (Direct Cost : ¥4,700,000)
Plasminogen (PG) deficient mice result in impaired cell migration and display delayed wound healing. However, fibrinogen deficiency in PG deficient mice corrects healing time. Consequently, these results suggest that the degradation of tissue-fibrin with plasmin (PM) is critical for cell migration. Angiostatin (AST) has been identified as an endogenous inhibitor of neovascularization. In 1998, AST has been shown to inhibit migration and tube formation of endothelial cells. AST, a fragment of PG, contains lysine-binding site (LBS) through which PG and PM bind to fibrin, cell membrane and alpha2-plasmin inhibitor (alpha2-PI). Thereby, we have analyzed the effect of cL2-PI on the PM-mediated cell migration and the inhibitory effect of AST.
1) Analysis of the mechanism of alpha2-PI to participate in tissue fibrinolysis : When fibrinogen or fibrin existed asan extracellular matrix, alpha2-PI was crosslinked to this by factor Xllla. Since alpha2-PI had a high affinity to selectin, we have ana
lyzed the sugar moiety of alpha2-PI.After degradation with hydrazine and treatment with sialidase, cQ-PI was studied by gyocomap analysis and anion exchange HPLC.Structure of oligosaccharides was deduced by RAMM analysis and the PNA binding. In result, alpha2-PI has N-linked oligosaccharides which has 1-3 sialic acids and 0-linked one containing one sialic acid. In addition, this study has suggested that alpha-Pl contains a sialyl- Lewis x structure.
2) Cell migration studies : The extracellular matrix which contained tibrinogen with crosslinked alpha2-PIattenuated endothelial cell migration. In addition, alpha2-PI delayed migration of endothelial cells, which were stimulated with lipopolysaccharide. Furthermore, alpha2-Pl appeared to neutralize the inhibitory effect of AST on cell migration, whereas a-amino caproic acid did not. Our results with the report that fibroblast growth factor specifically binds to fibrin indicate that alpha2-PI plays an important role in a fine regulation of wound healing. Less