Dear Colleagues,

In 2005, a Romanian team of scientists led by Professor Popescu described “mysterious” interstitial telocyte cells in the ovary, uterine tubes, uterus, vagina, mammary gland, and placenta. The most concise and pertinent definition of telocytes is that they are cells with extremely long and thin cytoplasmic projections called telopodes, the length of which is only surpassed by nerve cell axons. The main functions of telocytes include the regulation of hormone-dependent processes, intercellular signaling, immune surveillance, microenvironmental maintenance, and the nursing of stem cells. Although it is not yet generally accepted that telocytes are a distinct cell population with characteristic morphological and functional features, several articles on this cell type have been published in prestigious journals such as Nature and Annals of the New York Academy of Sciences. Diseases may develop in situations where the telocytes are functionally or morphologically damaged. The most commonly described gynecological and obstetric diseases that have been associated with telocytes (i.e. "telocytopathies") include premature ovarian failure, endometriosis, ectopic pregnancy, infertility, preeclampsia, and even breast cancer. The common denominator in many of these conditions is that their etiopathogenesis is either completely obscure or only partially known. Although the exact role of telocytes in these conditions has yet to be determined, multiple lines of research suggest they may have future clinical applications for improving the diagnosis and treatment of many conditions. Finally, the contribution of telocytes to regenerative medicine and tissue engineering is a buregeoning research area.

Prof. Dr. Ivan Varga

Guest Editor