The study, published in the February issue of Stem Cells, outlines how researchers discovered that the jelly-like connective tissue surrounding the blood vessels of the human umbilical cord, the so-called "Wharton's Jelly," is rich in mesenchymal progenitor cells cells that generate bone, cartilage and other tissues and can be harvested to generate an abundant supply in a short amount of time. This expandable source of progenitor cells could greatly improve bone marrow transplantation, a painful yet common procedure that currently has a 30 to 40 per cent success rate in treating disease.

Professor John Davies of U of T's Institute of Biomaterials and Biomedical Engineering (IBBME) and the study's lead author, says that the cells around the vessels human umbilical cord perivascular (HUCPV) cells were often discarded because previous research has concentrated only on the cord blood, where the frequency of mesenchymal stem cells is only one in 200 million. The frequency in the HUCPV cells is one in 300. "We hypothesized that since the umbilical cord grows so rapidly during fetal development, there must be some source producing these mesenchymal stem cells," says Davies. "We found that the jelly tissue immediately around the vessels had the richest population of these cells. Once we isolate them, it only takes 21 days to generate enough stem cells for up to 1000 therapeutic cell doses."

Bone marrow transplants treat diseases such as cancers and immune deficiency disorders by replacing diseased cells with fresh ones found inside bones. The transplant requires hematopoietic stem cells (blood-forming stem cells) and, ideally mesenchymal stem cells too, both of which are found in the marrow, to work efficiently. Other research indicates that infusing th
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Contact: J.E. Davies
davies@ecf.utoronto.ca
University of Toronto
8-Feb-2005