A team of researchers from Osaka City University, Japan, and Kinki University, Higashi-Osaka City, Japan, improved treatments used to spur new blood vessel growth in the hind legs of mice by using a “novel and feasible injectable cell scaffold,” dubbed a nanoscaffold (NS), the group reported in the online journal PLoS One on April 18.
The NS consists of biodegradable particles 50-100 micrometers in diameter to which cells can be attached. A micrometer is one-millionth of a meter. The particles were used to spur growth of new blood vessels in the back legs of mice with arterial sclerosis.
In human angiogenesis treatment, bone marrow stem cells taken from patients are injected into other areas of their bodies affected by disease. The injected cells release cytokines, a group of proteins that play a key role in blood vessel formation. But about 70 to 80 percent of the injected cells disappear from the areas within 48 hours, limiting the effects of the treatment. The effectiveness of the treatment is particularly low for patients with diabetes and dialysis patients suffering from peripheral arterial diseases (PAD).
In the experiments on the mice, the team injected the NS together with stem cells into their leg muscles and confirmed that the cells remained in the areas longer. The use of the NS boosted the limb survival rate fourfold, compared with treatment without the NS, and the volume of newly formed vessels grew sevenfold, the team said. The NS can also be used with other cells, including induced pluripotent stem (iPS) cells, which can develop into tissues of any kind, according to the team. The particles can also be used to treat strokes and heart attacks brought on by arterial sclerosis.
“We would like to give patients hope by making this new method ready for use in human treatment,” study co-author Shinya Fukumoto, MD, PhD, with the Department of Metabolism, Endocrinology, and Molecular Medicine, Osaka City University Graduate School of Medicine, was quoted as saying in The Japan Times.
Clinical trials for the new method are expected to start around 2015.