Stem Cells of Human Endometrium: Trash to Treasure

Abstract

Reproduction can be defined as the process by which an organism continues its species. The development of the normal female reproductive tract is a complex process. The paramesonephric ducts arise from the intermediate mesoderm, which are the precursors of the female reproductive organs that include uterus, fallopian tubes, cervix, and upper vagina [1]. The female reproductive system is designed to carry out several functions. It produces the female egg cells necessary for reproduction, called the ova or oocytes. The system is designed to transport the ova to the site of fertilization. Conception, the fertilization of an egg by a sperm, normally occurs in the fallopian tubes. The fertilized egg then gets implanted into the walls of the uterus, beginning the initial stages of pregnancy. If fertilization and/or implantation do not take place, the system is designed to menstruate (the monthly shedding of the uterine lining). In addition, the female reproductive system produces female sex hormones that maintain the reproductive cycle. Fallopian tubes are the passageways that egg cells enter after release from the ovaries. The Fallopian tubes lead to the uterus a muscular organ in the pelvic cavity. The inner lining, called the endometrium, thickens with blood and tissue in anticipation of a fertilized egg cell. If fertilization fails to occur, the endometrium degenerates and is shed in the process of menstruation. Based on its dynamic tissue remodeling during the menstrual cycle and pregnancy, it has been suggested that stem cells of the endometrium must possess a high regenerative potential [2, 3]. In this regard, the chapter provides an overview on endometrial stem cells with a special emphasis on its proliferation and multilineage differentiation potentials coupled with its in vivo therapeutic applications.