Multitasking human endometrium: a review of endometrial biopsy as a diagnostic tool, therapeutic applications, and a source of adult stem cells.
The endometrium is one of the most fascinating tissues in the human body. Its sole purpose is to enable implantation of an embryo during a very short window of opportunity in the menstrual cycle. When implantation does not take place, the endometrial cells are shed, enabling growth of a new endometrial layer the following month. Recently recognized stem cells may be the source through which this physiological turnover can take place. These cells, however, may also result in pathological conditions such as endometriosis, adenomyosis, and carcinoma when control by surrounding niche cells is lost. The methods to obtain endometrial tissue are critically reviewed, including the various catheters compared with the Pipelle. Recent advances in molecular studies of the endometrium enable researchers to define markers of implantation, and study the interaction between the embryo and the endometrium in vitro. Moreover, mechanisms by which wounding the endometrium by the biopsy catheter actually seems to improve embryo implantation are hypothesized. Finally, detection, isolation, and differentiation of adult endometrial stem cells have the potential to provide a resource for therapy of chronic conditions.


BACKGROUND
Obstetricians & Gynecologists, Family Physicians Leaning Objectives: After completion of this article, the reader should be able to explain the concept of the endometrium as a multi-tasking tissue, describe the role in health and potential role in medical care of adult stem cells in the endometrium, and describe the clinical characteristics of endometrial biopsy techniques.
Revel
Ariel
A
Department Obstetrics and Gynecology, Hadassah Medical Center and Hebrew University, Hadassah Medical School, Jerusalem, Israel. arielr2@hadassah.org.il
D053687:Adult Stem Cells / Q000166:cytology*; D001706:Biopsy / Q000379:methods*; D010064:Embryo Implantation; D004715:Endometriosis / Q000175:diagnosis*; D004717:Endometrium / Q000166:cytology* / Q000473:pathology*; D005260:Female; D006801:Humans; D015907:Hysteroscopy; D018084:Ultrasonography, Interventional