"When isolating a specific type of cell for transplantation into the body, the common thought is that the cells must be a pure culture. Getting a pure culture of muscle-derived cells, free of contaminating fibroblasts is difficult," said Michael B. Chancellor, M.D., professor, department of urology, University of Pittsburgh School of Medicine. "But, if the fibroblasts don't interfere with the muscle-derived cells, using these cells to regenerate muscle just got a great deal easier."
In animal models of stress urinary incontinence, researchers injected muscle-derived cells, fibroblasts and a mixture of MDC and fibroblasts into the tissue surrounding the urethra. Prior to injection, the models showed a significant decrease in leak point pressure, the point where the bladder leaks passively. Post-injection, all three groups showed an improved leak point pressure of the surrounding urethral tissue. Four weeks post-injection, MDC, fibroblasts and the combination MDC/fibroblast mixture were still present at their respective injection sites. There were no complications.
Fibroblasts did not interfere with the MDC ability to improve leak point pressure. However, the mechanism by which leak point pressure was improved, whether it be muscle regeneration from the MDC or a bulking effect from the fibroblasts is still being investigated. Prior animal model studies by the University of Pittsburgh group have found that MDC were able to regenerate deficient urethral muscle.
In addition to Dr. Chancellor, Irmute Usiene, Ron Jankowski, Ryan Pruchnic, Dongdeuk Kwon, Johnny Huard and Fernando de Miguel, all from the University of Pittsburgh, contributed to this study.
The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases and Cook MyoSite.