Nigel:
Thanks. Sure wish that I could go to the lab at Harvard and watch the procedure, start to finish. Must be fascinating.
As I've indicated elsewhere, I believe that the ALXN approach to dealing with hyperacute rejection is superior to those of BTRN (host engineering and extra-corporeal absorption), but not necessarily better than that of BTRN's partner, Novartis (both Imutran, with hDAF transgenics, and F. Bach et al., Novartis Center for Immunobiology, Beth Israel, have been beating this bush for years).
I'm interested in knowing more about the model.... most mice are deficient in the later "membrane attack" components of complement.
Here's an indication of how Novartis is involved in the real-world preparation that will be necessary to make xeno a reality......
Ann N Y Acad Sci 1998 Dec 30;862:121-4
Definition of a production specification for xenotransplantation. A
European perspective.
Iverson WO, Talbot T
Laboratory Animal Services-Research, Novartis Pharmaceuticals Corporation, Summit, New Jersey 07901-1398, USA.
william.iverson@novartis.pharma.com
In the absence of regulatory guidance on animal production for xenotransplantation and the need to conform to European, U.K.
and international standards of animal health and welfare, Imutran set up a forum of experts in 1994 to assess the risks
associated with the possible transmission of diseases from pig to man after transplantation of porcine tissue. This risk
assessment set the specification for Qualified Pathogen-Free pig production and the animal testing required to demonstrate that
the specification has been achieved. The invasive sampling required for detailed health monitoring of individual source animals is
in conflict with the aim of producing healthy, normal animals that are not subject to undue stress, and produces predominantly
retrospective data on a donor. Imutran has developed a sampling regime that qualifies age-class cohorts and the whole herd by
the routine testing of representative sentinel animals. Imutran set up a pilot production unit in 1995 and this unit has remained
populated beyond a 30-month period and has received in excess of 20 cohorts of animals by hysterectomy re-derivation.
Rigorous testing of sentinels and noninvasive testing of individuals have demonstrated that this pilot unit has achieved the
required specification on a routine basis in a system that has been designed to meet European ethical and animal welfare
concerns, within the constraints of the strict U.K. animal research laws and an ISO 9001 quality environment. |
