Improving Cartilage Healing with Adult Stem Cells

University of Guelph, February 6, 2007

Recovery can be a painful and lengthy process for an individual who has injured an elbow or knee. These parts of the body are composed of the slow-healing tissue, cartilage. Tissue that is damaged or missing is often lost forever. However, this may no longer be the case. Stem cells could possibly facilitate the needed tissue replacements as researchers at the University of Guelph are hoping.

Improving cartilage healing after joint injuries with the assistance of stem cells is the hope for biomedical sciences professor Dean and doctoral candidate Thomas. Joint injuries are frequent and expensive in horses, so the duo has made the decision to begin their research with an equine focus. In regards to human joint injuries, encouraging results from their research could serve as a model for future human treatment.

“Equine joints are similar to human joints in aspects such as joint thickness and spontaneous athletic injuries, so the research may be transferable,” said Thomas.

Isolating, differentiating, and expanding adult stem cells is the focus for much of the team's research. The source of the stem cells is blood from the umbilical cords of horses. It is relatively uncomplicated to collect equine cord blood, since most of the horses are observed when foaling. The cord blood can be collected at that time.

In contrast to embryo derived stem cells, acquiring cord blood samples is much easier and non-invasive. It is possible that cord blood stem cells can produce more diverse tissue types, and are capable of more divisions. Thomas says research indicates that bone marrow stem cells are not as "young" compared to cord blood stem cells, and thus, not as versatile. When used to help heal cartilage in another body, younger cord blood stem cells may also be less susceptible to rejection.

Dean and Thomas are excited to assemble as much information as possible since no other reports on isolating stem cells from equine cord blood exist. The building blocks of cartilage are made up of three different cell types including chondrocytes, and they have already succeeded in differentiating the cord blood to this level.

Dean said that it is difficult to duplicate the attachment to the underlying bone and the three-dimensional structure that is cartilage. But regardless, pieces of cartilage and bone grafted to the site of injury, osteochondral grafts, have produced encouraging results. Revealing more methods for surgically implanting grafts and reconstructing tissue at the location of injury is the hope for researchers.