Endometrial regenerative cells (ERCs) are stem cells isolated from the menstrual blood. ERCs share some markers with mesenchymal stem cells, such as, CD90 and CD105, but are unique in that they express hTERT and OCT-4. They can differentiate into several tissue types, including adipocytes, osteocytes, pancreas, neurons, muscle, respiratory epithelium and heptocytes. They also differentiate into endothelial cells and secrete angiogenic cytokines, such as PDGF-BB and angiopoietin.
Mononuclear cells are separated from menstrual blood by the standard Ficoll methodology and grown in complete DMEM medium supplemented with FCS (20%). Cells are cultured for 2 weeks, with medium changes twice a week. After two weeks in culture, an outgrowth of adherent cells with a fibroblast-like morphology is observed.