The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
David T. Curiel - One of the best experts on this subject based on the ideXlab platform.
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Efficient Transfection of Primary Cells in a Canine <B>HemophiliaB> B Model Using Adenovirus–Polylysine–DNA Complexes
Human Gene Therapy, 2008Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
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Efficient transfection of primary cells in a canine <B>HemophiliaB> B model using adenovirus-polylysine-DNA complexes
Hum Gene Ther, 1994Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
Katherine A. High - One of the best experts on this subject based on the ideXlab platform.
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translational data from adeno associated virus mediated gene therapy of <B>HemophiliaB> B in dogs
Human gene therapy. Clinical development, 2015Co-Authors: Timothy C. Nichols, Valder R Arruda, Margaret Whitford, Hansell H Stedman, Katherine A. HighAbstract:ABstract Preclinical testing of new therapeutic strategies in relevant animal models is an essential part of drug development. The choice of animal models of disease that are used in these studies is driven By the strength of the translational data for informing aBout safety, efficacy, and success or failure of human clinical trials. <B>HemophiliaB> B is a monogenic, X-linked, inherited Bleeding disorder that results from aBsent or dysfunctional coagulation factor IX (FIX). Regarding preclinical studies of adeno-associated virus (AAV)-mediated gene therapy for <B>HemophiliaB> B, dogs with severe <B>HemophiliaB> B (<1% FIX) provide well-characterized phenotypes and genotypes in which a species-specific transgene can Be expressed in a mixed genetic Background. Correction of the hemophilic coagulopathy By sustained expression of FIX, reduction of Bleeding events, and a comprehensive assessment of the humoral and cell-mediated immune responses to the expressed transgene and recomBinant AAV vector are all feasiBle end points...
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Efficient Transfection of Primary Cells in a Canine <B>HemophiliaB> B Model Using Adenovirus–Polylysine–DNA Complexes
Human Gene Therapy, 2008Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
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Clinical gene transfer studies for <B>HemophiliaB> B.
Seminars in Thrombosis and Hemostasis, 2004Co-Authors: Katherine A. HighAbstract:: <B>HemophiliaB> B, a deficiency of functional factor IX (FIX), has Been extensively explored as a model for gene transfer. Two U.S. Food and Drug Administration-approved clinical studies for <B>HemophiliaB> B have Been undertaken, Both using adeno-associated viral vectors (AAV). AAV vectors have tropism for liver, muscle, central nervous system, and the respiratory tract; Both skeletal muscle and liver have Been used as target tissues in the <B>HemophiliaB> B studies. In Both studies, proof of principle was first estaBlished in the <B>HemophiliaB> B dog model, with long-term expression of canine FIX at therapeutic levels achieved Before clinical studies were initiated. In the AAV-FIX muscle trial, vector was introduced into skeletal muscle of the upper and lower extremities of eight human patients By direct intramuscular injection. Muscle Biopsies taken 2 to 10 months postinjection demonstrated gene transfer and expression (By Southern Blot and immunofluorescence, respectively) in all patients, But circulating FIX levels were generally not >1%, and escalation of dose to levels that proved therapeutic in animals was thwarted By feasiBility issues regarding the numBer of injections required. Nevertheless, the study demonstrated that parenteral injection of AAV-FIX was safe at the doses tested, and could result in long-term expression of the transgene. Moreover, the general characteristics of transduction of human muscle were similar to those oBserved in other animal models. The safety and efficacy data estaBlished in the first trial formed the Basis for a second trial in which AAV-FIX is administered systemically to target the liver. The liver study is currently ongoing, with six patients enrolled to date.
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Efficient transfection of primary cells in a canine <B>HemophiliaB> B model using adenovirus-polylysine-DNA complexes
Hum Gene Ther, 1994Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
Jay N. Lozier - One of the best experts on this subject based on the ideXlab platform.
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Efficient Transfection of Primary Cells in a Canine <B>HemophiliaB> B Model Using Adenovirus–Polylysine–DNA Complexes
Human Gene Therapy, 2008Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
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Efficient transfection of primary cells in a canine <B>HemophiliaB> B model using adenovirus-polylysine-DNA complexes
Hum Gene Ther, 1994Co-Authors: Jay N. Lozier, P C Hu, K M Brinkhous, A.r. Thompson, M. Read, Katherine A. High, David T. CurielAbstract:We have used molecular conjugates containing comBinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with <B>HemophiliaB> B (factor IX deficiency), as well as a canine epithelial cell line. Transfection of canine <B>HemophiliaB> B fiBroBlasts with molecular conjugates resulted in efficient transfection and expression of luciferase DNA-adenovirus-polylysine (AdpL) conjugates or luciferase DNA-adenovirus-polylysine-transferrin (hTfpL/AdpL) conjugates. No expression in canine <B>HemophiliaB> B fiBroBlasts was evident after exposure to DNA alone, or DNA conjugated with polylysine and transferrin. Transfection efficiencies of 50% or more could Be demonstrated in cells transfected with a Beta-galactosidase reporter gene as part of an hTfpL/AdpL molecular conjugate. Transfection with canine factor IX AdpL conjugates or canine factor IX hTfpL/AdpL conjugates resulted in factor IX expression for more than 2 weeks in vitro in <B>HemophiliaB> B canine fiBroBlasts. Maximum levels of expression of over 700 ng of canine factor IX/10(6) cells/24 hr were demonstrated in fiBroBlasts after transfection with canine factor IX hTfpL/AdpL conjugates. Similar conjugates were used to transfect <B>HemophiliaB> B canine Bone marrow stromal cells and Madin-DarBy canine kidney cells that also expressed canine factor IX. The use of molecular conjugates to transfect primary cells may Be feasiBle as a means of in vitro or in vivo gene therapy for <B>HemophiliaB> B, and can Be tested in the canine <B>HemophiliaB> B model.
Darrel W Stafford - One of the best experts on this subject based on the ideXlab platform.
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dysfunctional endogenous fix impairs prophylaxis in a mouse <B>HemophiliaB> B model
Blood, 2019Co-Authors: Brian C Cooley, George J Broze, David M Mann, Lee G Pedersen, Darrel W StaffordAbstract:Factor IX (FIX) Binds to collagen IV (Col4) in the suB-endothelial Basement memBrane. In <B>HemophiliaB> B, this FIX-Col4 interaction reduces the plasma recovery of infused FIX and plays a role in hemostasis. Studies examining the recovery of infused BeneFix (FIX WT ) in null (cross-reactive material negative, CRM - ) <B>HemophiliaB> B mice suggest the concentration of Col4 readily availaBle for Binding FIX is ~405 nM with a 95% confidence interval of 374-436 nM. Thus, the vascular cache of FIX Bound to Col4 is several-fold the FIX level measured in plasma. In a mouse model of prophylactic therapy (testing hemostasis By saphenous vein Bleeding 7 days following infusion of 150 IU/kg FIX), FIX WT and the increased half-life FIXs Alprolix (FIX FC ) and Idelvion (FIX AlB ) produce comparaBle hemostatic results in CRM - mice. In Bleeding CRM - <B>HemophiliaB> B mice, the times to first clot at a saphenous vein injury site following the infusions of the FIX agents are significantly different: FIX WT l FIX FC l FIX AlB . Dysfunctional forms of FIX, however, circulate in the majority of patients with <B>HemophiliaB> B (CRM + ). In the mouse prophylactic therapy model, none of the FIX products improves hemostasis in CRM + mice expressing a dysfunctional FIX, FIX R333Q , that nevertheless competes with infused FIX for Col4 Binding and potentially other processes involving FIX. The results in this mouse model of CRM + <B>HemophiliaB> B demonstrate that the endogenous expression of a dysfunctional FIX can deleteriously affect the hemostatic response to prophylactic therapy.
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factor ix variants improve gene therapy efficacy for <B>HemophiliaB> B
Blood, 2005Co-Authors: Joerg Schuettrumpf, Darrel W Stafford, Roland W. Herzog, Alexander Schlachterman, Antje Kaufhold, Valder R ArrudaAbstract:Intramuscular injection of adeno-associated viral (AAV) vector to skeletal muscle of humans with <B>HemophiliaB> B is safe, But higher doses are required to achieve therapeutic factor IX (F.IX) levels. The efficacy of this approach is hampered By the retention of F.IX in muscle extracellular spaces and By the limiting capacity of muscle to synthesize fully active F.IX at high expression rates. To overcome these limitations, we constructed AAV vectors encoding F.IX variants for muscle- or liver-directed expression in <B>HemophiliaB> B mice. Circulating F.IX levels following intramuscular injection of AAV-F.IX-K5A/V10K, a variant with low-affinity to extracellular matrix, were 2-5 fold higher compared with wild-type (WT) F.IX, while the protein-specific activities remained similar. Expression of F.IX-R338A generated a protein with 2- or 6-fold higher specific activity than F.IX-WT following vector delivery to skeletal muscle or liver, respectively. F.IX-WT and variant forms provide effective hemostasis in vivo upon challenge By tail-clipping assay. Importantly, intramuscular injection of AAV-F.IX variants did not trigger antiBody formation to F.IX in mice tolerant to F.IX-WT. These studies demonstrate that F.IX variants provide a promising strategy to improve the efficacy for a variety of gene-Based therapies for <B>HemophiliaB> B.
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a coagulation factor ix deficient mouse model for human <B>HemophiliaB> B
Blood, 1997Co-Authors: Nobuyo Maeda, Oliver Smithies, David L Straight, Darrel W StaffordAbstract:Coagulation factor IX deficiency causes <B>HemophiliaB> B in humans. We have used gene targeting to develop a coagulation factor IX-deficient (factor IX-knockout) mouse strain. Mouse emBryonic stem (ES) cells were targeted By a socket-containing vector that replaces the promoter through exon 3 of the factor IX gene By neoΔHPRT, which is a functional neo gene plus a partially deleted hypoxanthine phosphoriBosyl transferase minigene. Chimeric mice generated using these socket-containing ES cells transmitted the targeted factor IX gene to their female offspring. Male offspring from these females were characterized and shown to exhiBit a phenotype similar to <B>HemophiliaB> B. This factor IX-deficient mouse strain will Be useful for studying gene therapy methods and structure-function relationships of recomBinant factor IX proteins in vivo.
Dougald M. Monroe - One of the best experts on this subject based on the ideXlab platform.
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Restoring Initial ThromBin Generation Does Not Normalize Cutaneous Wound Healing in <B>HemophiliaB> B.
Blood, 2006Co-Authors: Anna G. Mcdonald, H.r. Roberts, Maureane Hoffman, Ulla Hedner, Dougald M. MonroeAbstract:We recently descriBed aBnormal wound healing in a mouse model of <B>HemophiliaB> B (Hoffman et al, Blood 2006; DOI 10.1182/Blood-2006-05-020495). Specifically: epithelial closure was delayed in <B>HemophiliaB> B mice; hemophilic animals, unlike wild type, developed suBcutaneous hematomas; macrophage influx was delayed compared to wild-type mice; and, surprisingly, angiogenesis was enhanced in the <B>HemophiliaB> B mice. We hypothesized that restoring the initial hemostatic Burst of thromBin generation following wounding By administration of a single dose of factor IX (FIX) replacement or factor VIIa (FVIIa) Bypassing therapy would not only prevent Bleeding, But correct the suBsequent wound healing process. One dose of therapy was given thirty minutes prior to placement of a single three mm punch Biopsy wound on the dorsal skin of each wild type, untreated <B>HemophiliaB> B, and treated <B>HemophiliaB> B mouse. The size of the wounds was measured daily until full epithelial closure. The time course of epithelial closure in treated <B>HemophiliaB> B was intermediate Between wild type and untreated <B>HemophiliaB> B. FVIIa-treated <B>HemophiliaB> B Began to heal earlier than FIX-treated. Skin from the wound site was collected at different days and examined histologically. Macrophage influx was earlier in treated <B>HemophiliaB> B mice compared to untreated <B>HemophiliaB> B, likely a due to the increased thromBin and fiBrin acting as chemotactic agents. The macrophage influx in FVIIa-treated HB was significantly greater at certain time points than in FIX-treated mice, possiBly reflecting some signaling effect of TF/FVIIa in addition to its effects on thromBin generation. With the earlier influx in macrophages, hemogloBin was degraded to storage iron at earlier time points. However, tissue iron continued to persist in treated <B>HemophiliaB> B mice similar to untreated <B>HemophiliaB> B, suggesting continued reBleeding. FIX treatment led to significantly more angiogenesis than FVIIa. The reasons for this difference remain to Be determined. Untreated and some treated <B>HemophiliaB> B mice developed suBcutaneous hematomas Both Before and after wound closure. The early hematomas are likely caused By a comBination of the initial wounding trauma and vulneraBility to Bleeding related to the high level of vascularity within the granulation tissue. We propose the late hematomas are due to a cycle of Bleeding, leading to more inflammation with production of more pro-angiogenic cytokines, leading to greater angiogenesis with its attendant risk of Bleeding. In conclusion, restoring initial hemostatic thromBin generation did not normalize cutaneous wound healing in a <B>HemophiliaB> B mouse model. While the time frame of healing may not Be the same in human and murine <B>HemophiliaB>cs, our findings suggest that this model could Be helpful in rational determination of treatment schedules for replacement or Bypassing therapy following injury or surgery.
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cutaneous wound healing is impaired in <B>HemophiliaB> B
Blood, 2006Co-Authors: Maureane Hoffman, H.r. Roberts, Angie Lenkowski, Ulla Hedner, Anna Harger, Dougald M. MonroeAbstract:We used a mouse model to test the hypothesis that the time course and histology of wound healing is altered in <B>HemophiliaB> B. Punch Biopsies (3 mm) were placed in the skin of normal mice and mice with <B>HemophiliaB>. The size of the wounds was measured daily until the epidermal defect closed. All wounds closed in mice with <B>HemophiliaB> By 12 days, compared with 10 days in normal animals. Skin from the area of the wound was harvested at different time points and examined histologically. Hemophilic animals developed suBcutaneous hematomas; normal animals did not. Macrophage infiltration was significantly delayed in <B>HemophiliaB> B. Unexpectedly, hemophilic mice developed twice as many Blood vessels in the healing wounds as controls, and the increased vascularity persisted for at least 2 weeks. The deposition and persistence of ferric iron was also greater in hemophilic mice. We hypothesize that iron plays a role in promoting excess angiogenesis after wounding as it had Been proposed to do in hemophilic arthropathy. We have demonstrated that impaired coagulation leads to delayed wound healing with aBnormal histology. Our findings have significant implications for treatment of patients with <B>HemophiliaB>, and also highlight the importance of rapidly estaBlishing hemostasis following trauma or surgery.
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Delayed Wound Healing in <B>HemophiliaB> B Mice.
Blood, 2005Co-Authors: Maureane Hoffman, Angie Lenkowski, Jacqueline Brock, Ulla Hedner, Dougald M. MonroeAbstract:These studies use our previously reported wound healing model to estaBlish the mechanisms Behind the impaired wound healing we oBserved in <B>HemophiliaB> B animals. We hypothisized that thromBin mediated signals generated in response to the initial wound would Be aBsent or reduced in <B>HemophiliaB> B mice, leading to an impaired course of wound healing and poor angiogenesis. All work was done in accord with the US Amended Animal Welfare Act and was monitored By the Institutional Animal Care and Use Committee of UNC. Three mm circular dermal wounds were made in normal and <B>HemophiliaB> B mice. All wounds were treated with an antiBiotic gel at the time the wound was made. The mice were monitored for Bleeding Both at the time the wound was made and for delayed Bleeding. <B>HemophiliaB> B mice with excessive Bleeding were treated. The wounds were monitored for regrowth of the epithelial layer. The size of the area not covered By epithelial tissue was measured and expressed as square millimeters (wound size). We have previously reported that there is a significant difference in the time to wound healing Between untreated hemophilic (10 days) and normal animals (7 days). At the end of the time course, wound areas were excised and the skin was formalin fixed, paraffin emBedded, and sectioned. Essentially all <B>HemophiliaB> But no normal animals showed unresolved suBcutaneous hematoma. During the wound healing process, macrophage infiltration into the granulation tissue was significantly delayed. Unexpectedly, <B>HemophiliaB> B mice relative to wild type mice showed twice as many Blood vessels in the healing wound. This difference persisted out to two weeks after the wound was made and well after reepithelialization. Pretreatment (30 minutes prior to wounding) of <B>HemophiliaB> B mice with a single Bolus dose of human factor IX sufficient to give 1 U/mL corrected the wound healing time. Pretreated <B>HemophiliaB> B mice did not have oBvious suBcutaneous hematomoas. The oBservation that a single Bolus dose of factor IX prior to wounding a <B>HemophiliaB> B animal normalized the wound healing time provides a starting point for determining how different doses or different administration times effect wound healing. It also provides a starting point from which to compare the effects of Bypassing therapy on wound healing.
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Extravascular administration of factor IX: potential for replacement therapy of canine and human <B>HemophiliaB> B.
Thrombosis and Haemostasis, 1997Co-Authors: Darla K. Liles, H.r. Roberts, Dougald M. Monroe, Marjorie S. Read, Charles N. Landen, Celeste Lindley, Kenneth M. BrinkhousAbstract:ABstract Current therapy for <B>HemophiliaB> B requires large intravenous doses of factor IX (F.IX) given in the clinic or at home. Although home therapy is possiBle for many patients, it is often complicated By factors such as the lack of good venous access. Very little is known aBout extravascular routes for administering proteins like F.IX (57 kD) or other vitamin K-dependent procoagulant factors into the circulation. Questions aBout the aBsorption rate from extravascular administration as well as plasma recovery and BioavailaBility have arisen recently with the growing availaBility of highly purified procoagulant proteins and increased interest in gene therapy of <B>HemophiliaB> B. Therefore, a group of studies were undertaken to determine the aBsorption rate, plasma recovery, and BioavailaBility of high purity, human plasma-derived F.IX concentrates administered via extravascular routes in <B>HemophiliaB> B dogs and in one human <B>HemophiliaB> B suBject. Five <B>HemophiliaB> B dogs were given human F.IX via either a suBcutaneous (s.c.), intramuscular (i.m.), intraperitoneal (i.p.) or intravenous (i.v.) route. In a suBsequent study, a single SC administration of human F.IX was compared to an identical i.v. dose of F.IX in the human <B>HemophiliaB> B suBject. All extravascular routes of F.IX administration in Both the canine and human gave lower levels of circulating plasma F.IX than the i.v. route, however all routes resulted in measuraBle F.IX activity. Of the extravascular routes, the i.m. injection in the canine resulted in a BioavailaBility of 82.8%, while the s.c. injection resulted in a BioavailaBility of 63.5%. F.IX reached the plasma compartment By all extravascular routes used, confirming that F.IX can Be aBsorBed extravascularly. The duration of measuraBle F.IX activity following extravascular administration is prolonged Beyond that typically seen with i.v. administration. These data show that significant levels of F.IX may Be oBtained via s.c. injection in canine and human <B>HemophiliaB> B suBjects and further highlight the potential of extravascular routes of administration for future experimental and clinical uses of F.IX and other procoagulant proteins.