Function of human factor H and I on xenosurface.
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.
Yoshitatsu
M
M
Division of Organ Transplantation, Biomedical Research Center, Osaka University Graduate School of Medicine, Suita, Osaka, 565-0871, Japan.
Miyagawa
S
S
Mikata
S
S
Matsunami
K
K
Yamada
M
M
Murase
A
A
Sawa
Y
Y
Ohtake
S
S
Matsuda
H
H
Shirakura
R
R
D000818:Animals; D001483:Base Sequence; D018958:CD55 Antigens / Q000235:genetics / Q000378:metabolism; D016466:CHO Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D003167:Complement Activation; D003176:Complement C3 / Q000378:metabolism; D003181:Complement C4 / Q000378:metabolism; D017242:Complement Factor H / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006224:Cricetinae; D017931:DNA Primers / Q000235:genetics; D005340:Fibrinogen / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006084:Graft Rejection / Q000517:prevention & control; D006801:Humans; D008954:Models, Biological; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013552:Swine; D014162:Transfection; D014183:Transplantation, Heterologous
D018958:CD55 Antigens; C493495:CFH protein, human; D003176:Complement C3; D003181:Complement C4; D017931:DNA Primers; D011994:Recombinant Proteins; D017242:Complement Factor H; D005340:Fibrinogen