{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T00:27:43Z","timestamp":1760488063447,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:00:00Z","timestamp":1760054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>The human endometrium is unique in that it has a high potential for regeneration after menstruation without scarring. Although growth factors are thought to be responsible for scar formation, it has recently been shown for foetal skin that CD26-negative fibroblasts are essential. Thus, we investigated whether CD26 might be involved in scar formation. Primary human endometrial stromal cells (HPESCs) were stimulated with interleukin-1 alpha (IL1\u03b1) to induce CD26 protein expression, and secretion of the scar-associated proteins collagen 1 alpha 1 (COL1A1) and TGF-\u03b23 was measured using ELISAs. The contribution of CD26 to wound closure was analysed using a wound healing assay. The CD26 inhibitor diprotin A (DPA) was used to attenuate CD26 activity. Immunohistochemistry of human uterine samples showed negligible stromal staining of CD26, but CD26 was abundant in the endometrial glands. Treatment of CD26-negative HPESCs with IL1\u03b1 induced CD26 protein expression, strongly stimulated wound healing in vitro, and increased secretion of COL1A1, but decreased TGF-\u03b23 secretion. DPA effectively attenuated all IL1\u03b1-induced effects. We suggest that the stromal non-expression of the scar-associated protein CD26 might contribute to non-scarring during endometrial wound healing.<\/jats:p>","DOI":"10.3390\/biom15101433","type":"journal-article","created":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T12:32:47Z","timestamp":1760099567000},"page":"1433","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Contribution of CD26-Negative Fibroblasts to Endometrial Scarring"],"prefix":"10.3390","volume":"15","author":[{"given":"Muhammad Assad","family":"Riaz","sequence":"first","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Clara Marie","family":"Pecher","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Franziska Louisa","family":"Kary","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jane Bosibori","family":"Maoga","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raimund","family":"Dietze","sequence":"additional","affiliation":[{"name":"Institute of Molecular Biology and Tumor Research (IMT), Philipps University, D-35043 Marburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2909-9492","authenticated-orcid":false,"given":"Felix","family":"Zeppernick","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0331-8781","authenticated-orcid":false,"given":"Ivo","family":"Meinhold-Heerlein","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5878-3050","authenticated-orcid":false,"given":"Lutz","family":"Konrad","sequence":"additional","affiliation":[{"name":"Center of Gynecology and Obstetrics, Faculty of Medicine, Justus Liebig University, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1149","DOI":"10.1152\/physrev.00031.2019","article-title":"Physiology of the endometrium and regulation of menstruation","volume":"100","author":"Critchley","year":"2020","journal-title":"Physiol. 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