Transgenic pigs expressing human CD59, in combination with human membrane cofactor protein and human decay-accelerating factor.
BACKGROUND
The expression of human complement regulators has been proved as an effective strategy to overcome hyperacute rejection in discordant xenogeneic organ transplantation. In this study, we tested the hypotheses that expression of triple transgenes for human complement regulators and provide more effective protection to the transplanted pig tissues.


METHODS
Pigs transgenic for human complement regulatory proteins, human CD59 (hCD59) and human membrane cofactor protein (hMCP), have been generated using large genomic constructs. Heterozygous human decay-accelerating factor (hDAF) transgenic pigs, from a previously established line, were bred with hCD59 or hCD59 plus hMCP pigs to produce animals that expressed both hCD59 and hDAF, or expressed triple transgenes hCD59, hDAF and hMCP.


RESULTS
All three transgenes were widely expressed in most of the tissues analyzed, but the expression of hMCP was at low levels. In cytotoxicity assays on porcine peripheral blood mononuclear cells, the expression of a single transgenic protein, hCD59, or hCD59 in combination with hMCP provided similar protection against human complement-mediated damage as the single expression of hDAF. However, the expression of triple transgenic proteins or double hCD59 and hDAF transgenic proteins provided greater protection than either hCD59 or hDAF alone.


CONCLUSIONS
Thus, pigs transgenic for multiple transgenes provide a greater degree of human complement regulation and hence might be more suitable for xenotransplantation.
Zhou
Chun-Yan
CY
Imutran Ltd. (a Novartis Pharma AG Company), PO Box 399, Cambridge CB2 2YP, UK. chunyanzhou@bjmu.edu.cn
McInnes
Elizabeth
E
Copeman
Laura
L
Langford
Gillian
G
Parsons
Nicola
N
Lancaster
Richard
R
Richards
Andrew
A
Carrington
Christine
C
Thompson
Simon
S
D000818:Animals; D030801:Animals, Genetically Modified; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D018958:CD55 Antigens / Q000235:genetics / Q000378:metabolism*; D018957:CD59 Antigens / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D012867:Skin / Q000166:cytology / Q000378:metabolism; D013552:Swine; D019076:Transgenes / Q000235:genetics*
D015703:Antigens, CD; C497857:CD46 protein, human; D018958:CD55 Antigens; D018957:CD59 Antigens; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins