{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T10:58:23Z","timestamp":1775818703563,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T00:00:00Z","timestamp":1775779200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Alloantibodies directed against human platelet antigens and human leukocyte antigens are implicated in several immune-mediated platelet disorders, including platelet transfusion refractoriness, post-transfusion purpura and fetal and neonatal alloimmune thrombocytopenia. Reliable and simultaneous detection of these antibodies is essential for accurate diagnosis and appropriate clinical management. The aim of this study was to determine the prevalence and specificity spectrum of anti-HLA and anti-HPA alloantibodies in patients with suspected immune-mediated platelet disorders using a multiplex bead-based assay, and to evaluate its diagnostic utility in a Serbian cohort. Materials and Methods: A bead-based glycoprotein-specific antibody detection assay was performed using monoclonal antibodies specific for platelet glycoproteins and HLA class I molecules, separately coupled to Luminex microbeads. Serum samples were collected from 259 patients, including 234 patients with thrombocytopenia, 11 with neonatal alloimmune thrombocytopenia, and 14 with suspected platelet transfusion refractoriness. All samples were tested using the PakLx Luminex assay, and results were interpreted with MatchIt! Antibody software. Results: Of the 259 tested samples, 72 (27.8%) were positive for HLA and\/or platelet-specific antibodies. Among the positive samples, 29.2% contained HLA class I antibodies, 45.8% contained platelet-specific antibodies, and 25% showed combined HLA and platelet antibody positivity. The most frequently detected platelet-specific antibodies were directed against GPIIb\/IIIa (HPA-1, -3, -4) and GPIa\/IIa (HPA-5). Conclusions: This first analysis of platelet alloantibodies in a Serbian cohort demonstrates a high prevalence of antibody positivity in patients with neonatal alloimmune thrombocytopenia and platelet transfusion refractoriness, with anti-HPA-1a as the predominant specificity. The significant association between clinical presentation and antibody profile underscores the need for targeted diagnostic testing. Multiplex bead-based technology provides comprehensive alloantibody detection, facilitating optimized transfusion management in immune-mediated platelet disorders.<\/jats:p>","DOI":"10.3390\/medicina62040725","type":"journal-article","created":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T09:08:12Z","timestamp":1775812092000},"page":"725","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Prevalence and Specificity of Anti-HPA and Anti-HLA Antibodies in Patients with Suspected Immune-Mediated Platelet Disorders: A Single-Center Study from Serbia"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5048-7898","authenticated-orcid":false,"given":"Svetlana","family":"Vojvodi\u0107","sequence":"first","affiliation":[{"name":"Department of Transfusiology, Faculty of Medicine, University of Novi Sad, 21000 Novi Sad, Serbia"},{"name":"Blood Transfusion Institute of Vojvodina, 21000 Novi Sad, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3092-4768","authenticated-orcid":false,"given":"Jasmina","family":"Gruji\u0107","sequence":"additional","affiliation":[{"name":"Department of Transfusiology, Faculty of Medicine, University of Novi Sad, 21000 Novi Sad, Serbia"},{"name":"Blood Transfusion Institute of Vojvodina, 21000 Novi Sad, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"26348535241284460","DOI":"10.1177\/26348535241284460","article-title":"Platelet Transfusion Refractoriness","volume":"18","author":"Lubis","year":"2024","journal-title":"Plasmatology"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Garraud, O., Cognasse, F., and Moncharmont, P. (2019). Immunological Features in the Process of Blood Platelet-Induced Alloimmunisation, with a Focus on Platelet Component Transfusion. Diseases, 7.","DOI":"10.3390\/diseases7010007"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"671","DOI":"10.1111\/bjh.13639","article-title":"Recent Progress in Understanding the Pathogenesis of Fetal and Neonatal Alloimmune Thrombocytopenia","volume":"171","author":"Curtis","year":"2015","journal-title":"Br. J. Haematol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1157","DOI":"10.1097\/AOG.0b013e31823403f4","article-title":"Fetal and Neonatal Alloimmune Thrombocytopenia: A Management Algorithm Based on Risk Stratification","volume":"118","author":"Pacheco","year":"2011","journal-title":"Obstet. Gynecol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"738","DOI":"10.1111\/1471-0528.13343","article-title":"True Risk of Fetal\/Neonatal Alloimmune Thrombocytopenia in Subsequent Pregnancies: A Prospective Observational Follow-Up Study","volume":"123","author":"Tiller","year":"2016","journal-title":"BJOG Int. J. Obstet. Gynaecol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"102607","DOI":"10.1016\/j.coi.2025.102607","article-title":"Insights into Platelet Post-Transfusional Human Leukocyte Antigen I Immunization","volume":"96","year":"2025","journal-title":"Curr. Opin. Immunol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1111\/trf.14122","article-title":"Detection and Identification of Platelet Antibodies Using a Sensitive Multiplex Assay System-Platelet Antibody Bead Array","volume":"57","author":"Metzner","year":"2017","journal-title":"Transfusion"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1771","DOI":"10.1056\/NEJMoa1212772","article-title":"A No-Prophylaxis Platelet-Transfusion Strategy for Hematologic Cancers","volume":"368","author":"Stanworth","year":"2013","journal-title":"N. Engl. J. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"101038","DOI":"10.1016\/j.blre.2022.101038","article-title":"Fetal and Neonatal Alloimmune Thrombocytopenia: Current Pathophysiological Insights and Perspectives for Future Diagnostics and Treatment","volume":"59","author":"Stam","year":"2023","journal-title":"Blood Rev."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1105","DOI":"10.1111\/vox.13538","article-title":"An Optimized Procedure for Luminex-Based Human Platelet Antigen-Specific Antibody Screening and Identification (PakLx Assay) with a Cost-Effective Approach and Improved Sensitivity","volume":"118","author":"Bertrand","year":"2023","journal-title":"Vox Sang."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"101135","DOI":"10.1016\/j.blre.2023.101135","article-title":"Platelet Transfusion Refractoriness Due to HLA Alloimmunization: Evolving Paradigms in Mechanisms and Management","volume":"62","author":"Panch","year":"2023","journal-title":"Blood Rev."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"S97","DOI":"10.1016\/j.htct.2024.06.004","article-title":"Platelet Antibody Detection Assays: A Single-Laboratory Comparison of MAIPA, PIFT, and Microsphere-Based Multiplex Assays Pak-Lx","volume":"46","author":"Costa","year":"2024","journal-title":"Hematol. Transfus. Cell Ther."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1111\/bjh.14572","article-title":"24-h Continuous Infusion of Platelets for Patients with Platelet Transfusion Refractoriness","volume":"181","author":"Cid","year":"2018","journal-title":"Br. J. Haematol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1016\/j.ajog.2021.04.211","article-title":"New Developments in Fetal and Neonatal Alloimmune Thrombocytopenia","volume":"225","author":"Bussel","year":"2021","journal-title":"Am. J. Obstet. Gynecol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.tracli.2022.08.140","article-title":"An Overview of Red Blood Cell and Platelet Alloimmunisation in Transfusion","volume":"29","author":"Garraud","year":"2022","journal-title":"Transfus. Clin. Biol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.tmrv.2020.09.010","article-title":"Human Leukocyte Antigen Alloimmunization and Alloimmune Platelet Refractoriness","volume":"34","author":"Saris","year":"2020","journal-title":"Transfus. Med. Rev."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1016\/j.humimm.2017.07.004","article-title":"Polymorphisms of the Human Platelet Antigen-1, -2, -3, -5, and -15 Systems and Acute Cellular Liver Transplant Rejection","volume":"78","author":"Thude","year":"2017","journal-title":"Hum. Immunol."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Couvidou, A., Rojas-Jim\u00e9nez, G., Dupuis, A., and Ma\u00eetre, B. (2023). Anti-HLA Class I Alloantibodies in Platelet Transfusion Refractoriness: From Mechanisms and Determinants to Therapeutic Prospects. Front. Immunol., 14.","DOI":"10.3389\/fimmu.2023.1125367"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1887","DOI":"10.1182\/blood.2019003434","article-title":"Platelet Alloantibody Detection: Moving Ahead","volume":"134","author":"Wilkie","year":"2019","journal-title":"Blood"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"655","DOI":"10.1097\/MOH.0b013e3282eec526","article-title":"New Paradigms in the Management of Alloimmune Refractoriness to Platelet Transfusions","volume":"14","author":"Vassallo","year":"2007","journal-title":"Curr. Opin. Hematol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1111\/trf.13950","article-title":"HLA-DRB3*01:01 Is a Predictor of Immunization against Human Platelet Antigen-1a but Not of the Severity of Fetal and Neonatal Alloimmune Thrombocytopenia","volume":"57","author":"Papenkort","year":"2017","journal-title":"Transfusion"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1016\/j.tracli.2018.01.003","article-title":"Platelet Component Transfusion and Alloimmunization: Where Do We Stand?","volume":"25","author":"Moncharmont","year":"2018","journal-title":"Transfus. Clin. Biol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"37","DOI":"10.21037\/aob-21-36","article-title":"CD36 immunization causing platelet transfusion refractoriness: Narrative review","volume":"6","author":"Sullivan","year":"2021","journal-title":"Ann. Blood"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1111\/vox.13779","article-title":"Screening of pregnant women for foetal neonatal alloimmune thrombocytopenia: A cost-utility analysis","volume":"120","author":"Tersteeg","year":"2025","journal-title":"Vox Sang."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/4\/725\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T09:57:04Z","timestamp":1775815024000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/4\/725"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,10]]},"references-count":24,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["medicina62040725"],"URL":"https:\/\/doi.org\/10.3390\/medicina62040725","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,10]]}}}