The first two Europeans genetically modified pigs for xenotransplantation were born in Italy, at the Laboratory of reproductive technologies (Avantea) of Cremona, directed by prof. Cesare Galli, already 'father' of the first cloned bull Galileo and of the first horse Prometea. The two pigs, one male and one female - say experts - have been produced as part of the research project 'Xenome': a consortium funded by the European Commission, which brings together leading international laboratories in preclinical research on xenotransplantation and cloning of animals . This success was achieved thanks to the close collaboration with the Massachusetts General Hospital (MGH) in Boston - said Prof. Galli – The two pigs are called 'GAL-knockout' or 'GAL-KO' because they lack the antigen responsible for hyperacute rejection, which occurs when the pig organs are transplanted into primates. Xenotransplantation - remember the lab team - is a procedure in which tissue or organs are transplanted from one species to another.
The pig is the species of choice for its many anatomical and physiological similarities with humans. The objective of the research on xenotransplantation is to provide, in the future, a reliable source of cells, tissues and organs to the thousands of patients on the waiting list for a transplant because of the chronic shortage of human organs from a donor. To this figure must be added the recent and significant advances made in the field of genetic engineering and cloning, which have greatly improved the production of pigs carrying the genes necessary to overcome the immunological barriers to xenotransplantation, ensure Galli and colleagues. Biosafety is another important aspect to be addressed - continue - The ethical aspect, finally, was the subject of intense debate and now the majority of bioethicist experts accept xenotransplantation. To date, in fact, the pigs 'gmo' for xenotransplantation do not differ phenotypically from the millions of pigs which are reared in the world for the production of meat.
The elimination of the GAL antigen is thus the first step to get to generate pig organs that may be better tolerated by the immune system, and then transplanted successfully before in primates and then in humans. The Italian researchers point out that the Sachs’ team of the MGH was the first in the world to remove the gene required to generate GAL-KO pigs. The American center has therefore provided the cell lines derived from its pigs to Avantea, which then used them in the cloning procedure (the somatic nuclear transfer, or SNTC) that generated pigs carry the same genetic modification. Other pregnancies are ongoing and new animals will be born in the next few months. These pigs will be produced to increase the potential number of organs for preclinical research, which in Europe will be made precisely by the consortium 'Xenome'.
The mission of the scientists of Cremona is to improve the compatibility of the organs to be implanted, to reduce the immune response and inflammation that currently limited to a few months, the long-term survival of transpanted organ. For this purpose, several genes have already been introduced in the cell lines used today for cloning, in order to generate animals with further genetic modifications. This concludes the Laboratory, is a long-term goal that seeks to generate new intellectual property to be shared with 'Xenome' and MGH. The researchers ultimately aim to create industrial and biomedical opportunities for the breeding of these hi-tech pigs and the use of their tissue in preclinical research.