Viable pigs after simultaneous inactivation of porcine MHC class I and three xenoreactive antigen genes GGTA1, CMAH and B4GALNT2

• DOI: 10.1111/xen.12560
• Publication Date: 2019-10-08T08:41:06Z
• Authors: Konrad Fischer; Beate Rieblinger; Rabea Hein; Riccardo Sfriso; Julia Zuber; Andrea Fischer; Bernhard Klinger; Wei Liang; Krzysztof Flisiko...; Mayuko Kurome; Valeri Zakhartchenko; Barbara Kessler; Eckhard Wolf; Robert Rieben; Reinhard Schwinzer; Alexander Kind; Angelika Schnieke
• Keywords: Xenotransplantation

Abstract Background Cell surface carbohydrate antigens play a major role in the rejection of porcine xenografts. The most important for human recipients are α‐1,3 Gal (Galactose‐alpha‐1,3‐galactose) causing hyperacute rejection, also Neu5Gc (N‐glycolylneuraminic acid) and Sd(a) blood group both which likely to elicit acute vascular given known immune status. Porcine cells with knockouts three genes responsible, GGTA1 , CMAH B4GALNT2 revealed minimal xenoreactive antibody binding after incubation serum. However, leucocyte antigen (HLA) antibodies cross‐reacted swine class I (SLA‐I). We previously demonstrated efficient generation pigs multiple xeno‐transgenes placed at single genomic locus. Here we wished assess whether key can be simultaneously inactivated if combination multi‐transgenic background further reduces deposition complement activation. Methods Multiplex CRISPR/Cas9 gene editing somatic cell nuclear transfer were used generate carrying functional SLA I. Fibroblasts derived from one‐ four‐fold knockout animals, (human CD46, CD55, CD59, HO1 A20) examine effects on IgG IgM or activation vitro. Results Pigs generated genes. In vitro assays that all four reduced kidney more effectively than double knockouts. combined alone C3b/c C4b/c such an extent had no significant additional effect. Conclusion showed several xenoprotective transgenes readily these modifications will have xenograft survival.