{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T01:58:33Z","timestamp":1777946313257,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,4,24]],"date-time":"2009-04-24T00:00:00Z","timestamp":1240531200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,4,24]],"date-time":"2009-04-24T00:00:00Z","timestamp":1240531200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Haemostasis"],"abstract":"<jats:p>Plasma from 15 patients with haemophilia A and 4 patients with von Willebrand\u2019s disease (VWD) has been investigated for the presence of antibodies to von Willebrand factor (VWF) using ELISA and immunoblotting systems. All plasma samples were also analyzed for anticoagulant activity against factor VIII coagulant activity (FVIIl\u00b7C) and ristocetin co-factor activity of VWF (RCof). The patients were on regualr prophylaxis or treated \u2018on demand\u2019 with different commerical FVIII-VWF complex concentrates. Neutralizing activity against FVIIl\u00b7C was only found in haemophiliacs (in 3 out of 15), whereas anti-RCof was only found in VWD patients (in 2 out of 4). In ELISA, antibodies to VWF were detected in 3 of the VWD patients. However, using the immunoblotting system, antibodies to the multimeric structure of VWF were found not only in VWD patients (in 3 out of 4); remarkably 9 out of 15 haemophiliacs also reacted with VWF, including some that did not show FVIIl\u00b7C inhibitors. The pattern of VWF multimers obtained with the antibodies showed differences among the patients. These findings are discussed together with the mechanisms by which such antibodies could have developed in haemophilia A patients who are not deficient in this particular protein (VWF).<\/jats:p>","DOI":"10.1159\/000215991","type":"journal-article","created":{"date-parts":[[2009,4,24]],"date-time":"2009-04-24T09:41:27Z","timestamp":1240566087000},"page":"284-291","source":"Crossref","is-referenced-by-count":0,"title":["Induced Antibodies to von Willebrand Factor"],"prefix":"10.1159","author":[{"given":"Birgit","family":"Hessel","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hans","family":"Johnsson","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angela","family":"Silveira","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,4,24]]},"container-title":["Haemostasis"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/215991","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000215991","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T16:38:32Z","timestamp":1777739912000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000215991"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,4,24]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000215991","archive":["Portico"],"relation":{},"ISSN":["0301-0147","1423-0038"],"issn-type":[{"value":"0301-0147","type":"print"},{"value":"1423-0038","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,4,24]]}}}