Five Tissue Types Made From Pig Stem Cells

Five kinds of tissue, including bone, blood vessels, fat and nerve cells, have been made from adult stem cells taken from pig blood.

Researchers at the College of Veterinary Medicine at the University of Missouri-Columbia first developed pigs with fluorescent tissue so they could follow the growth of their stem cells after they were transplanted into other organisms.

The team then took adult stem cells from the pigs' blood, isolated them and created stable cell lines and exposed the cell lines to different biochemical signals to produce specific kinds of tissue

The initial isolation seemed to be the key to their success, the researchers said. The scientists said they would next test whether their method can produce enough cells for disease therapy, and if similar adult stem cells can be isolated from humans.

The researchers said that, while embryonic stem cells (ESCs) produce many types of tissue in the lab, they are unstable and can be easily confused by the complex metabolism of adult organisms.

When transplanted into animals, ESCs sometimes produce unwanted cell types or tumors, and this has created safety concerns about their therapeutic potential. Adult stem cells stay on developmental pathways more reliably, but can't produce as many tissue types. The team's main achievement is the number of tissues they created, and that all of the tissues have remained stable, the researchers noted.

The team's work is the cover article in the August edition of Stem Cells and Development.