Identificación, caracterización y aislamiento de células madre somáticas del endometrio murino y humano.

Nowadays the identification, characterization and isolation of somatic stem cells in the majority of the tissues/organs have been one of the major challenges carried out by the cellular biology. The endometrium in menstruating and non-menstruating species has cycles of growth, differentiation and regeneration during the reproductive life. In this regard, the concept that endometrial stem cells are responsible for the regenerative capacity of this tissue was proposed many years ago. This study is based in two models: murine and human. Although the mice do not menstruate, in the murine endometrium occurs phenomenon of growth, differentiation, regression and reabsorption. For this reason, in the reproductive and regenerative medicine, the mouse is a well- established animal model for research studies based on the existence of the presence of somatic stem cells in this tissue. A reliable method for identifying the putative endometrial somatic stem cells in murine endometrium is based on the use of 5-brome-2-deoxyuridine (BrdU). Moreover, uteri from BrdU-treated mice were analysed by inmuno-histochemistry in an attempt to co-localize LRCs with undifferentiated markers like c-Kit and Oct-4 The Hoechst method and the isolation of the Side Population (SP) are one of the techniques applied to isolate human somatic stem cells from different tissues. In this study we demonstrate the existence of SP cells in the human endometrium. Furthermore, the SP cells isolated expressed typical undifferentiated markers such as c-KIT and OCT-4 at mRNA levels, and they have an intermediate profile of telomerase activity between human embryonic stem cells line and differentiated cells. The phenotypic analysis of this SP population is suggestive of a putative mesenchymal origin (CD90+).