garyx:
PPL split from Roslyn with agricultural applications, non-human stuff. GERN purchased the remainder of Roslyn.
Many groups have claimed the pig pluripotent progenitor. Many groups say that the claimant groups are full of it.
There are a few simple questions to ask. Is the value exclusively in having identical pigs as a donor pool for transplantable organs? If so, are cloned pigs of significantly greater value than the inbred herds of BioTransplant?
(note: I do not know the answer)
PPL mentions intellectual property regarding the alpha 1-3 gal transferase gene. What advantages do they hold over Alexion? Here's some background......
Xenotransplantation 1999 Feb;6(1):6-16
Comparative analysis of three genetic modifications designed to inhibit
human serum-mediated cytolysis.
Costa C, Zhao L, Decesare S, Fodor WL
Department of Molecular Sciences, Alexion Pharmaceuticals Inc., New Haven, CT 06511, USA.
Hyperacute rejection (HAR) remains a critical immunologic hurdle in the development of xenogeneic organs for human
transplantation. Strategies that simultaneously eliminate both natural antibody reactivity and complement activation on the
xenogeneic cell surface may be the best approach to achieve clinical application of xenogeneic vascularized organ
transplantation. We have developed multiple lines of genetically manipulated mice to evaluate the combination of different
genetic approaches aimed at inhibiting antibody and complement-mediated cell lysis. We utilized transgenic mice expressing the
human complement inhibitor, CD59, the human 1,2-fucosyltransferase (H-transferase, HT) and the
alpha1,3-galactosyltransferase (alpha1,3-GT) knock-out mouse line (Gal KO). Our data show that expression of hCD59 in
combination with HT expression or the null phenotype of alpha1,3-GT are equally effective at preventing human
serum-mediated cytolysis. Interestingly, the triple combination affords no additional protective effect. Therefore, coexpression
of HT and a complement inhibitor is the most immediate strategy to genetically engineer transgenic pigs to be used as
xenogeneic donors. |
