Functional histology and possible clinical significance of recently discovered telocytes inside the female reproductive system

Key discoveries of recent years comprise detection of telocytes. These cells of connective tissue have extremely long cytoplasmic processes through which they form functionally connected spatial networks. Through their processes they mutually contact and functionally connect also cells of the immune system, nerve fibres and smooth muscle cells. They are located in various parts of the female reproductive system where they can perform specifically significant functions, which are summarized in our literature review. Literature regarding telocytes and interstitial Cajal-like cells was reviewed using scientific databases PubMed/Medline, SCOPUS, and Web of Knowledge. Among other things telocytes regulate peristaltic muscle movements in the uterine tubes. Their decreased activity, e.g., in inflammatory diseases or endometriosis, causes disorders of a transport function through the uterine tubes resulting in infertility or tubal pregnancy. In the uterine myometrium they are, first, responsible for regulation of muscle contraction (in expelling menstrual blood or in childbirth) and, second, they participate also in immune surveillance during embryo implantation. They likely control also uterine involution post partum. Their function in the vagina has not been elucidated yet, but probably they participate in production of slow contraction waves during sexual intercourse. In the mammary gland their function may be to regulate cellular proliferation and apoptosis, thus they may play a role also in the development and growth of tumours. In the placenta, they may monitor and regulate blood flow through chorionic villi and they participate in aetiopathogenesis of preeclampsia. However, all above-mentioned functions of telocytes are purely hypothetic and have been published only recently. Therefore, only further research will demonstrate whether this recently discovered cell population will really play a key role in all processes mentioned, or whether it is just an effort of scientists to clarify unknown cause of some diseases in gynaecology and obstetrics. Our literature review is completed by our own original photomicrographs documenting telocytes in various organs of the female reproductive system.