Pittsburgh researchers have published more evidence that the solid part of the umbilical cord is a rich source of adult stem cells (tissue stem cells/mesenchymal stem cells). The cells are obtained from a gel-like part of the solid cord, known as Wharton's jelly, and from blood vessel walls. They note that the stem cells isolated from the solid cord can be grown to high numbers of stable cells, with potential to treat muscular, cartilage, and skeletal disorders. The results are published in the Journal of Biomedicine and Biotechnology.

Previously, several groups have isolated adult stem cells from the solid part of the umbilical cord and shown their potential. Scientists in Taiwan showed the ability to differentiate the cells into various lineages, including towards cardiomyocytes, have transformed the stem cells into islet-like clusters that secrete insulin and relieved induced diabetes in experimental animals, and have shown that the cells were beneficial to wound healing after spinal cord injury in rats.

A group at Kansas State University was one of the first to isolate stem cells from the solid umbilical cord, and have published an array of studies on the cells' abilities, including forming neurons and neural cell types, alleviating Parkinson's symptoms in an animal model, and demonstrating that the stem cells from umbilical cord do not elicit immune response; they have also published a review on the stem cells from Wharton's jelly in the journal Stem Cells.