Analysis of the function of bone marrow stromal cell antigen, BST-1 (CD157) to support B cells

1 . Roles for BST-1 in arthritis induced by type 2 collagen：Soluble BST-1 transgenic mice (a line S15) and wild type mice （n=6 and 8, respectively）had been backcrossed with DBA/ 1j for 8 generations，100μg of bovine type 2 collagen和incomplete Freund adjuvant.虽然theincidence of arthritis in S15 mice increased from those of wild mice. The incidence of arthritis in S15 mice increased from those of wild mice. The incidence of arthritis inbst-1ko因为mice,which been backcrossed with DBA/ 1j (N=15) for 5generations,was higher than that of wild mice（n=13） at day 57 (100% and 69%，respectively . There was no difference in the severity. BST-1 does not important roles incollagen induced arthritis.(2) Generation of BST-1/CD38 double knockout mouse：ES cell clones deleted both CD38 and BST-1 genes were selected and the chimeric mice were obtained. 1Analysis of F1 generation revealed successful targeting of CD38 and BST-1 genes will be obtained by(3) Receptor function:Crosslinking of BST-1 on the surface ofmBST-1BAF, a pro B cell line transfected with murine BST-1 cDNA, resulted in the cell aggregation，indicating that signals through BST-1 induce cell adhesion.(4) BST-1Ligand：cDNA library for表达式cloning was prepared form a B cell line which binds BST-1. Candidates ofcDNA for human BST-1ligand has not been obtained after screening of 2x10 - D14 - D1 clones。

(1) Roles for BST-1 in arthritis induced by type 2 collagen : Soluble BST-1 transgenic mice (a line S15) and wild type mice (n=6 and 8, respectively), which had been backcrossed with DBA/1J for 8 generations, were immunized with 100μg of bovine type 2 collagen and incomplete Freund adjuvant. Although the incidence of arthritis in S15 mice increased from those of wild mice. The incidence of arthritis in BST-1KO mice, which had been backcrossed with DBA/1J (N=15) for 5generations ,was higher than that of wild mice (n=13) at day 57 (100% and 69%, respectively). There was no difference in the severity. BST-1 does not have important roles in collagen induced arthritis.(2) Generation of BST-1/CD38 double knockout mouse : ES cell clones deleted both CD38 and BST-1 genes were selected and the chimeric mice were obtained. Analysis of F1 generation revealed successful targeting of CD38 and BST-1 genes will be obtained by crossing the mice of F1 generation.(3) Receptor function :Crosslinking of BST-1 on the surface of mBST-1BAF, a pro B cell line transfected with murine BST-1 cDNA, resulted in the cell aggregation, indicating that signals through BST-1 induce cell adhesion.(4) BST-1Ligand: cDNA library for expression cloning was prepared form a B cell line which binds BST-1. Candidates of cDNA for human BST-1ligand has not been obtained after screening of 2x10ィイD14ィエD1 clones.