Isolation and characterization of endometrial mesenchymal stem cells and the evaluation of surface markers in comparison to bone marrow mesenchymal stem cells

Stem cells are undifferentiated cells able to self-renew as well as to produce more differentiated daughter cells. In this study, stem cells were isolated from the endometrium and were then compared with the mesenchymal stem cells for their nature to be determined. Endometrial samples from healthy donors with informed consent after laparoscopy were collected by a gynecologist. The bone marrow samples were aspirated from femur by a hematologist. At least 5 mL of blood was removed and the tissue is at least one square centimeter. After three successive passages, the stem cell surface markers of CD90, CD105, CD146, CD34, CD73, CD44, CD133, and CD45 were analyzed using flowcytometry. The karyotype analysis was also performed for the adherent cells. Endometrial stem cells were successfully isolated from the five samples. Adherent cells in flowcytometric analysis showed the positive expression of surface markers to be CD146: 59.3%, CD105: 98.3%, CD90: 95.8%, CD34: 0.9%, CD 45: 1.1%, CD73: 96%, CD44: 84%, and CD133: 1.4% while in bone marrow mesenchymal stem cells the expression of markers were CD105: 98.6%, CD90: 98.4%, CD34: 0.5%, CD73: 97.9%, CD44: 89.3%, CD146:13%, CD45: 0.3%, and CD133: 0.6%. The morphology of endometrial cells, spindle-like mesenchymal cells, the mode of application, and 44XX karyotype were normal. Stem cells isolated from the endometrial tissue had a heterogeneous population of the cells and high levels of expression of specific surface markers of stem cells especially the mesoderm lineage.