Researchers seeking new and more abundant sources of stem cells for use in regenerative medicine have identified a potentially unlimited, noncontroversial, easily collectable, and inexpensive source — menstrual blood.

Stromal stem cells — cells that are present in connective tissues — have recently been identified in endometrial tissues of the uterus. When the fresh growth of tissue and blood vessels is shed during each menstrual cycle, some cells with regenerative capabilities are present and collectable.

"Stromal stem cells derived from menstrual blood exhibit stem cell properties, such as the capacity for self-renewal and multipotency," said Amit N. Patel, MD, MS, Director of Cardiac Cell Therapy at the University of Pittsburgh's McGowan Institute of Regenerative Medicine. "Uterine stromal cells have similar multipotent markers found in bone marrow stem cells and originate in part from bone marrow."

Published in the most recent issue of Cell Transplantation (Volume 17, issue 3), the study examined to what degree MenSCs demonstrated an ability to differentiate into a variety of cell lineages.

Tests showed that MenSCs could differentiate into adipogenic, chondrogenic, osteogenic, ectodermal, mesodermal, cardiogenic, and neural cell lineages. According to Patel, the sample MenSCs expanded rapidly and maintained greater than 50 percent of their telomerase activity when compared to human embryonic stem cells and better than bone marrow-derived stem cells. "Studies have demonstrated that MenSCs are easily expandable to clinical relevance and express multipotent markers at both the molecular and cellular level," concluded Patel.