Cloning of organs to enhance health and longevity
Written by – Jain Virmal
Cloning is the most trendy term getting momentum in today’s time with irrespective of the field. With respond to science this has totally changed the working of medical minds to treat the infection or disease by answering to problem through “cloning”. Cloning of organ basically relays on altering the surface antigen to protect organ from undergoing necrosis due to immune response engaged by antibodies on encountering the transplant organ. Humoral immune response is the major system that raises immunity against foreign antigen. So in case of xenotransplant the organ isolated from pig was genetically altered to suppress the expression of -1,2-galactosyltransferase and express 1,2-fucosylosyltransferase. This increased the life of the organ in human recipient as antibody could not raise immune response because the epitope expressed on the organ was similar to that found on the original organ. This could be an effective way of gaining longevity to transplanted organs (1). Longevity can also be increased by means of engineering the animal for expression of hCD59 i.e. a glycosyl-phosphatidylinositol-anchored cell surface glycoprotein. It inhibits the formation of complement system that cause apoptosis. The organ expressing it was found to be highly tolerant to anti-porcine antibody and to human complement system (2). Expression of HLA-E molecules on grafting organ provides protection against human NK cells (3). Success rate of liver transplant can be increased by means of introducing gene encoding radical scavenger enzymes like dismutase that help the transplant organ to reperfusion there by making efficient blood vessel connection in turn enhance the health of the organ (4,5). Skeletal muscle cells and stem cells like bone marrow, embryonic and amniotic fluid cells are been found effective in repairing heart injury as well as generating artificial hearts which are called mini hearts (6).
These all possibilities are been made to make transplant healthier and to increase longevity. If it works out properly it would be boon to the humans over diseases and infections.
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- Fodor WL. et al, Expression of a Functional Human Complement Inhibitor in a Transgenic Pig as a Model for the Prevention of Xenogeneic Hyperacute Organ Rejection. Proc. Natl. Acad. Sci. USA. 1994 (91). 11153-11157.
- Klymiuk N. et al, Genetic Modification of Pigs as Organ Donors for Xenotransplantation. Mol. Reprod. Dev. 2010 (77): 209–221.
- Lehmann TG. et al, Gene Delivery of Cu/Zn-Superoxide Dismutase Improves Graft Function After Transplantation of Fatty Livers in the Rat. Hepatology. 2000 6(32).
- Lehmann TG. et al, Delivery of Cu/Zn superoxide dismutase genes with a viral vector minimizes Iiver injury and Improves Survival after Liver Transplantation in the Aat. Transplantation. 2000 6(69). 1051-1057.
- Atala A. et al, Engineering Organs. Current Opinion in Biotechnology. 2009 (20). 575–592.