{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T05:18:04Z","timestamp":1788585484773,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001711","name":"Swiss National Science Foundation","doi-asserted-by":"crossref","award":["31-063868.00"],"award-info":[{"award-number":["31-063868.00"]}],"id":[{"id":"10.13039\/501100001711","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001711","name":"Swiss National Science Foundation","doi-asserted-by":"crossref","award":["31-107754.04"],"award-info":[{"award-number":["31-107754.04"]}],"id":[{"id":"10.13039\/501100001711","id-type":"DOI","asserted-by":"crossref"}]},{"award":["31-063868.00"],"award-info":[{"award-number":["31-063868.00"]}],"id":[{"id":"https:\/\/ror.org\/00yjd3n13","id-type":"ROR","asserted-by":"publisher"}]},{"award":["31-107754.04"],"award-info":[{"award-number":["31-107754.04"]}],"id":[{"id":"https:\/\/ror.org\/00yjd3n13","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Platelets express several glycophosphatidylinositol-(GPI-) anchored receptors, mainly involved in protection against lysis by activated complements. Most of these are well-characterised and are expressed on other blood cells. More recently, CD109 with a mass of 175 kDa was also shown to be a GPI-anchored receptor, surface expressed only on activated platelets, with a role as a co-receptor for transforming growth factor-\u03b2 (TGF-\u03b2). CD109 is expressed on a wide range of cells and is a marker for various types of tumors. Activated platelets express an even larger GPI-anchored receptor at about 500 kDa. We have now isolated this and identified it as fibrocystin L, also known as polycystic kidney hepatic disease L1 (PKHD1L1). Fibrocystin L, like other platelet GPI-anchored receptors, is missing or deficient in paroxysmal nocturnal hemoglobinuria. Fibrocystin L is also expressed in activated T-cells and may be involved in immune responses. Recently, there have been additional reports of PKHD1L1 expression and roles as a coat protein of hair-cell stereocilia essential for normal hearing, as well as reports of them in the dentate gyrus in mice involved in susceptibility to seizure. In all these cases, GPI anchors were not reported, but neither were they tested for. During the fluorescence microscopy studies, we used CD109 as a control and observed that it is also a granule protein that had not been previously reported.<\/jats:p>","DOI":"10.3390\/ijms27177796","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T09:48:36Z","timestamp":1788256116000},"page":"7796","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Activated Platelets Express GPI-Anchored Fibrocystin-L (PKHD1L1), from Granules, Absent or Deficient in Paroxysmal Nocturnal Hemoglobinuria"],"prefix":"10.3390","volume":"27","author":[{"given":"Janos","family":"Polgar","sequence":"first","affiliation":[{"name":"Theodor Kocher Institute, University of Berne, Freiestrasse 1, CH-3012 Berne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"given":"Jeannine M.","family":"Clemetson","sequence":"additional","affiliation":[{"name":"Theodor Kocher Institute, University of Berne, Freiestrasse 1, CH-3012 Berne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edith","family":"Magnenat","sequence":"additional","affiliation":[{"name":"Serono Pharmaceutical Research Institute, 14, Chemin des Aulx, Plan-les-Ouates, CH-1228 Geneva, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Timothy N.","family":"Wells","sequence":"additional","affiliation":[{"name":"Serono Pharmaceutical Research Institute, 14, Chemin des Aulx, Plan-les-Ouates, CH-1228 Geneva, Switzerland"},{"name":"Medicines for Malaria Venture, 20 Route des Pre-Bois, CH-1215 Geneva, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helena","family":"R\u00f6ss","sequence":"additional","affiliation":[{"name":"Topographische und Klinische Anatomie, Institute of Anatomy, University of Berne, CH-3012 Berne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Rochat","sequence":"additional","affiliation":[{"name":"Department of Haematology, Department of Biomedical Research, Inselspital, University of Berne, CH-3008 Berne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"}]},{"given":"Lorenzo A.","family":"Alberio","sequence":"additional","affiliation":[{"name":"Department of Haematology, Centre Hospitalier Universitaire Vaudois CHUV, University of Lausanne, CH-1011 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenneth J.","family":"Clemetson","sequence":"additional","affiliation":[{"name":"Theodor Kocher Institute, University of Berne, Freiestrasse 1, CH-3012 Berne, Switzerland"},{"name":"Department of Haematology, Department of Biomedical Research, Inselspital, University of Berne, CH-3008 Berne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref_1","first-page":"485","article-title":"Structure and function of decay accelerating factor CD55","volume":"123","author":"Wang","year":"1994","journal-title":"J. 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