{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T11:40:09Z","timestamp":1780918809727,"version":"3.54.1"},"reference-count":68,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,8,29]],"date-time":"2020-08-29T00:00:00Z","timestamp":1598659200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001655","name":"Deutscher Akademischer Austauschdienst","doi-asserted-by":"publisher","award":["Rustaveli-DAAD-Fellowship Programme, no. 91677531"],"award-info":[{"award-number":["Rustaveli-DAAD-Fellowship Programme, no. 91677531"]}],"id":[{"id":"10.13039\/501100001655","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Changes in the number and cytotoxic potential of uterine Natural Killer (uNK) cells have been associated with reduced fertility. To provide a better characterization of immunophenotypes in the endometrium of women with uRPL (unexplained recurrent pregnancy loss), we examined the applicability of a set of five immune cell markers. The concentration (cells\/mm2) of CD45+ leukocytes, CD56+ uNK cells, and CD138+ plasma cells as well as of CD16+ and CD57+ cells, which indicate high cytotoxic uNK cells, were assessed by immunohistochemistry in endometrial biopsies from 61 uRPL patients and 10 controls. Control fertile endometria presented 90\u2013300 CD56+ uNK cells\/mm2. uRPL cases were classified in subgroups of low (uRPL-CD56low &lt; 90 cells\/mm2), normal (uRPL-CD56normal 90\u2013300 cells\/mm2), and high uNK cell counts (uRPL-CD56high &gt; 300 cells\/mm2). Some cases from the uRPL-CD56low and uRPL-CD56normal subgroups showed elevated proportions of cytotoxic CD16+ and CD57+ cells in relation to CD56+ cells. In the uRPL-CD56high subgroup, the CD57\/CD56 ratio was reduced in most samples and the CD16\/CD56 ratio was unaltered. Analysis of CD138 excluded the influence of chronic endometritis on these observations. Our results reinforce a link between uRPL and a dysfunctional endometrial environment associated with distinct immune cell profiles.<\/jats:p>","DOI":"10.3390\/diagnostics10090650","type":"journal-article","created":{"date-parts":[[2020,8,30]],"date-time":"2020-08-30T06:06:22Z","timestamp":1598767582000},"page":"650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Beyond Uterine Natural Killer Cell Numbers in Unexplained Recurrent Pregnancy Loss: Combined Analysis of CD45, CD56, CD16, CD57, and CD138"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1339-0832","authenticated-orcid":false,"given":"Maia","family":"Chiokadze","sequence":"first","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"},{"name":"The Center for Reproductive Medicine \u201cUniverse\u201d, 0159 Tbilisi, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christin","family":"B\u00e4r","sequence":"additional","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jana","family":"Pastuschek","sequence":"additional","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Boris V.","family":"Dons\u2019koi","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology, Institute of Pediatrics, Obstetrics and Gynecology, National Academy of Medical Sciences of Ukraine, 04050 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kseniia G.","family":"Khazhylenko","sequence":"additional","affiliation":[{"name":"Reproductive Medicine Clinic Isida, 02000 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ekkehard","family":"Schleu\u00dfner","sequence":"additional","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5299-595X","authenticated-orcid":false,"given":"Udo R.","family":"Markert","sequence":"additional","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2889-5921","authenticated-orcid":false,"given":"Rodolfo R.","family":"Favaro","sequence":"additional","affiliation":[{"name":"Placenta Lab, Department of Obstetrics, Jena University Hospital, 07747 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Practice Committee of the American Society for Reproductive Medicine (2012). 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