First report of telocytes in human ovarian stroma: an ultrastructural and immunohistochemical study

Telocytes (TCs) are interstitial cells characterized by long, thin cytoplasmic extensions called telopodes. Although their presence has been established in various organs, data on their existence and organization within the human ovary remain limited. This study aimed to identify and describe telocytes in the ovarian stroma using immunohistochemical, immunofluorescence, and ultrastructural methods. Ovarian tissues from women aged 24–65 years who underwent total hysterectomy and bilateral salpingo-oophorectomy for nonmalignant uterine diseases were analyzed. TCs were identified by CD34 co-expression with c-KIT, vimentin, platelet-derived growth factor receptor (PDGFR)-β, and alpha-smooth muscle actin (α-SMA) and confirmed by transmission electron microscopy with immunogold labeling. The results demonstrated that telocytes form two to three discontinuous layers around the adventitia of large and medium-sized blood vessels and establish close contacts with stromal components, including smooth muscle cells. This spatial organization suggests their involvement in intercellular communication and stromal coordination within the ovarian microenvironment. These findings provide the first ultrastructural and immunohistochemical evidence of telocytes in the human ovarian stroma and highlight the need for further studies to clarify their physiological and pathological roles in ovarian function, including potential morphological and molecular differences among females of different age groups. Similar content being viewed by others Data availability No datasets were generated or analyzed during the current study.

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This study was funded by the Istanbul University-Cerrahpasa Scientific Research Projects Unit, project no. 37035 and 36206. Author information Authors and Affiliations Contributions M.P. conducted all experiments, data analysis, and manuscript preparation. G.T. supervised and led the overall project. S.I. performed the pathological examination of the tissue samples. I.C., C.S., and S.S.C. assisted during the surgeries and provided the ovarian tissue samples. All authors reviewed and approved the final manuscript. Corresponding author Ethics declarations Conflict of interest The authors declare no competing interests. Additional information Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Rights and permissions Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. About this article Cite this article Purelku, M., Cebi, C., Cebi, S. et al. First report of telocytes in human ovarian stroma: an ultrastructural and immunohistochemical study. Histochem Cell Biol 163, 119 (2025). https://doi.org/10.1007/s00418-025-02448-4 Received: Accepted: Published: Version of record: DOI: https://doi.org/10.1007/s00418-025-02448-4