UCLA scientists who purified stem cells derived from fat tissue and used them to grow bone discovered that the new bone formed faster and was of higher quality than bone created using traditional methods. The finding may one day eliminate the need for painful bone grafts that use material taken from patients during invasive procedures.
Adipose, or fat, tissue is thought to be an ideal source of mesenchymal stem cells - cells capable of developing into bone, cartilage, muscle and other tissues - because such cells are plentiful in the tissue and easily obtained through procedures like liposuction, says Chia Soo, MD, vice chair of research for the UCLA Division of Plastic and Reconstructive Surgery and a member of the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA.
The study was published in Stem Cells Translational Medicine.
Rather than culturing stem cells, a team led by Dr. Soo and Professor of Orthopaedic Surgery Bruno Péault, PhD, used a cell-sorting machine to isolate and purify human perivascular stem cells (hPSC) from adipose tissue and demonstrated that those cells worked far better than other cell lines in creating bone. They also showed that a growth factor called NELL-1, discovered by a member of the UCLA dentistry faculty, enhanced bone formation in their animal model.
"People have shown that culture-derived cells could grow bone, but ours are a fresh cell population, and we didn't have to go through the culture process, which can take weeks," Dr. Soo says. "The best bone graft is still your own bone, but that resource is in limited supply and sometimes not of good quality. What we show here is a faster and better way to create bone that could have clinical applications."
Drs. Soo and Péault's team grew the hPSCs together with NELL-1 in a muscle pouch, a place where bone is not normally grown, and used X-rays to determine that the cells did indeed become bone. "The purified human hPSCs formed significantly more bone in comparison to (other lines) by all parameters," Dr. Soo says. "And these cells are plentiful enough that patients with not much excess body fat can donate their own fat tissue."
"An Abundant Perivascular Source of Stem Cells for Bone Tissue Engineering," Stem Cells Translational Medicine, September 5, 2012