Yoshitatsu M, Miyagawa S, Mikata S, Matsunami K, Yamada M, Murase A, Sawa Y, Ohtake S, Matsuda H, Shirakura R
Division of Organ Transplantation, Biomedical Research Center, Osaka University Graduate School of Medicine, Suita, Osaka, 565-0871, Japan.
Biochem Biophys Res Commun. 1999 Nov 19;265(2):556-62. doi: 10.1006/bbrc.1999.1713.
The cell membrane-bound forms of mini-factor H with 1-4 short consensus repeats (fH-PI) and factor I (fI-PI) were constructed. Swine endothelial cell (SEC) lines and Chinese hamster ovary (CHO) cell expressing fH-PI or fI-PI were established and confirmed by flow cytometry. The cell lysate of the SEC line expressing fH-PI showed strong cofactor activity for the cleavage of C3b, and fI-PI demonstrated the protease activity for C4b and C3b not only in the fluid phase but also on the cell membrane. In addition, fH-PI blocked human complement-mediated cell lysis by approximately 30-40%. An SEC line with a low expression of fI-PI showed a weak inhibition of cell lysis in human serum, whereas a CHO cell transfectant with a high expression of fI-PI showed over a 60% inhibition of cell lysis. The results suggest that fH-PI and fI-PI have potential for use in clinical xenotransplantation.
构建了具有1-4个短共识重复序列的细胞膜结合型微小补体因子H（fH-PI）和补体因子I（fI-PI）。通过流式细胞术建立并确认了表达fH-PI或fI-PI的猪内皮细胞（SEC）系和中国仓鼠卵巢（CHO）细胞系。表达fH-PI的SEC系细胞裂解物对C3b的裂解显示出很强的辅因子活性，并且fI-PI不仅在液相中，而且在细胞膜上都表现出对C4b和C3b的蛋白酶活性。此外，fH-PI可将人补体介导的细胞裂解阻断约30-40%。fI-PI低表达的SEC系在人血清中对细胞裂解的抑制作用较弱，而fI-PI高表达的CHO细胞转染子对细胞裂解的抑制作用超过60%。结果表明，fH-PI和fI-PI在临床异种移植中具有应用潜力。
