We have generated a mouse where the clotting factor IX (FIX) gene has been disrupted by homologous recombination. The FIX nullizygous (-/-) mouse was devoid of factor IX antigen in plasma. Consistent with the bleeding disorder, the factor IX coagulant activities for wild-type (+/+), heterozygous (+/-), and homozygous (-/-) mice were 92%, 53%, and <5%, respectively, in activated partial thrombop...

INTRODUCTION Gene therapy could prevent bleeding in hemophilia. However, antibodies could inhibit coagulation, while cytotoxic T lymphocytes could destroy modified cells. The immaturity of the newborn immune system might prevent these immune responses from occurring after neonatal gene therapy. MATERIALS AND METHODS Newborn dogs, cats, or mice were injected intravenously with a retroviral vec...

DNA from nine hemophilia B patients who produce anti-factor IX inhibitors (antibodies), including two brothers, was analyzed by the Southern blotting method and hybridization with factor IX cDNA, intragenomic, and 3'-flanking probes. Two inhibitor patients were shown to have total deletions of the factor IX gene. Two other inhibitor patients, the brothers, were shown to have a presumably identi...

The majority of cases of human hemophilia B are the result of missense mutations in the coagulation factor IX gene and defective circulating factor IX is detectable in most patients. The available mouse factor IX knockout models of hemophilia B (FIXKO mouse) reproduce the bleeding phenotype of human hemophilia B, but because the models produce no factor IX they fail to reproduce the dominant hu...

The majority of cases of human hemophilia B are the result of missense mutations in the coagulation factor IX gene and defective circulating factor IX is detectable in most patients. The available mouse factor IX knockout models of hemophilia B (FIXKO mouse) reproduce the bleeding phenotype of human hemophilia B, but because the models produce no factor IX they fail to reproduce the dominant hu...

in this study, anion-exchange chromatography was used to purify factor vii and factor ix from prothrombin complex (ppsb), which contains coagulation factors ii, vii, ix and x. for this purpose, deae-sepharose cl-6b gel , pharmacia column xk-26 , high flow rate and two stepwise gradients with phosphate citrate buffer were used. the yield of the two lyophylized products, factor vii and factor ix ...

A potentially cost-effective strategy for gene therapy of hemophilia B is to create universal factor IX-secreting cell lines suitable for implantation into different patients. To avoid graft rejection, the implanted cells are enclosed in alginate-polylysine-alginate microcapsules that are permeable to factor IX diffusion, but impermeable to the hosts' immune mediators. This nonautologous approa...

In aiming to develop a gene therapy approach for hemophilia B, we expressed and characterized human factor IX in rat capillary endothelial cells (CECs). Moloney murine leukemia virus-derived retrovirus vectors that contain human factor IX cDNA linked to heterologous promoters and the neomycin-resistant gene were constructed and employed to prepare recombinant retroviruses. Rat CECs and NIH 3T3 ...

Background: Hemophilia B is a bleeding disorder with a recessive X-linked inheritance pattern, in which the infected individuals have low levels of factor IX in their plasma. Affected individuals may have bleeding episodes after trauma or spontaneously considering the plasma level of factor IX. In order to prevent these episodes and to control bleeding, they should use coagulation factor concen...

In this study, anion-exchange chromatography was used to purify factor VII and factor IX from prothrombin complex (PPSB), which contains coagulation factors II, VII, IX and X. For this purpose, DEAE-Sepharose CL-6B gel , Pharmacia column XK-26 , high flow rate and two stepwise gradients with phosphate citrate buffer were used. The yield of the two lyophylized products, factor VII and factor...