There is a worldwide shortage of organs for clinical transplantation and many patients due to receive new organs die on the waiting list. It is reasonable to consider that organs from other species, may soon be engineered to minimize the risk of serious rejection and used as an alternative to human tissues, possibly ending organ shortages. For most purposes, xenotransplantation will use pigs as the source of tissues and organs. There are ethical, safety and husbandry difficulties in exploiting primates, whereas pigs have large litters and grow to the appropriate size. Xenotransplantation could provide a supply of cells, tissues and organs to treat a number of serious human diseases. The challenge in xenotransplantation is to find a way to persuade the human body’s immune system to
accept an animal organ. Xenotransplantation comprises of several important steps from interdisciplinary areas. The first step involves preparation of competitive, inactivating and regulatory gene constructs. These gene constructs should allow (i) knock-out of 1,3 galactosyltransferase (1,3GT) gene, (ii) expression of complement proteins and (iii) regulate expression of proteins.
Potentially, xenotransplantation could provide enough healthy organs to offer transplantation to thousands of patients on waiting lists worldwide. The pig has been selected as the most suitable species for the development of xenotransplantation. The pig’s organs are approximately the same size as human organs, both in infancy and adulthood. Additionally, pigs have been domesticated for many centuries. They breed relatively quickly with large litters, so a large number of life-saving organs could potentially be generated quickly when necessary. Generation of transgenic pigs could prevent hyperacute immunological response and make possible use for xenotransplantation.
Last minute info: Homozygous pigs with human 1,2-fucosyltraneserase gene were obtained. Three patent applications filed.