Exploring Anti-FVIII Antibodies in Haemophilia A - Role in In Vitro Haemostasis and Clinical Disease
type: CreativeWork
description: Haemophilia A (HA) is caused by defective synthesis of coagulation factor VIII(FVIII), which has serious effects on haemostasis; joints being the most common site of bleeding. The development of FVIII replacements has improved the situation for patients with haemophilia such that chronic arthropathy can be prevented, and life expectancy and the quality of life have increased. However, approximately 20-30% of patients suffering from severe HA develop neutralizing antibodies (inhibitors) against FVIII. Alternative treatment, using by-passing agents, is available for patients exhibiting inhibitors, although these can only be used for the short-term treatment of acute haemorrhage and as prophylaxis during surgery. Furthermore, the clinical response to by-passing products is unpredictable. Two of the studies included in this thesis evaluated the response to by-passing therapy in plasma from patients with HA. The variation in thrombin production within families was found to be significantly lower than the variation between families, indicating that a familial predisposition may influence thrombin formation in response to by-passing agents (Paper I). Moreover, FVIII clotting factors were found to potentiate the in vitro effect of by-passing agents on thrombin formation in plasma from patients with HA exhibiting inhibitors, indicating that further assessment of this treatment strategy in a clinical context is warranted (Paper II). Not all anti-FVIII antibodies have neutralizing capacity. In the studies presented in Papers III & V, non-neutralizing anti-FVIII antibodies(NNAs) were investigated in two different cohorts, using an enzyme-linked immunosorbent assay (ELISA). NNAs were detected in 18.9% of siblings with HA, and in 12.8% of unrelated HA subjects followed for four years. The antibody response was assayed using three different rFVIII products. The antibody response was found to be heterogeneous, to vary considerably between individuals (Papers III and V), and also ov…
abstract: Haemophilia A (HA) is caused by defective synthesis of coagulation factor VIII(FVIII), which has serious effects on haemostasis; joints being the most common site of bleeding. The development of FVIII replacements has improved the situation for patients with haemophilia such that chronic arthropathy can be prevented, and life expectancy and the quality of life have increased. However, approximately 20-30% of patients suffering from severe HA develop neutralizing antibodies (inhibitors) against FVIII. Alternative treatment, using by-passing agents, is available for patients exhibiting inhibitors, although these can only be used for the short-term treatment of acute haemorrhage and as prophylaxis during surgery. Furthermore, the clinical response to by-passing products is unpredictable. Two of the studies included in this thesis evaluated the response to by-passing therapy in plasma from patients with HA. The variation in thrombin production within families was found to be significantly lower than the variation between families, indicating that a familial predisposition may influence thrombin formation in response to by-passing agents (Paper I). Moreover, FVIII clotting factors were found to potentiate the in vitro effect of by-passing agents on thrombin formation in plasma from patients with HA exhibiting inhibitors, indicating that further assessment of this treatment strategy in a clinical context is warranted (Paper II). Not all anti-FVIII antibodies have neutralizing capacity. In the studies presented in Papers III & V, non-neutralizing anti-FVIII antibodies(NNAs) were investigated in two different cohorts, using an enzyme-linked immunosorbent assay (ELISA). NNAs were detected in 18.9% of siblings with HA, and in 12.8% of unrelated HA subjects followed for four years. The antibody response was assayed using three different rFVIII products. The antibody response was found to be heterogeneous, to vary considerably between individuals (Papers III and V), and also ov…
author: Klintman, Jenny
language: eng
keywords: Cardiology and Cardiovascular Disease, hemophilia A, inhibitors, non-neutralizing anti-FVIII antibodies, thrombin generation assay, ELISA
date published: 2013
date modified: 2026-07-24T02:59:36Z
provider: University of Lund
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Department of Clinical Sciences, Lund University