scholarly journals Erythroid-specific Human Factor IX Delivery From In Vivo Selected Hematopoietic Stem Cells Following Nonmyeloablative Conditioning in Hemophilia B Mice

2008 ◽  
Vol 16 (10) ◽  
pp. 1745-1752 ◽  
Author(s):  
Alex H Chang ◽  
Matthias T Stephan ◽  
Leszek Lisowski ◽  
Michel Sadelain
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Human Factor ◽  
Factor Ix ◽  
Hemophilia B ◽  
Hematopoietic Stem ◽  
Human Factor Ix ◽  
B Mice

Mesenchymal Stromal Cells Gene-Enhanced To Express Human Factor IX and Their In Vivo Use for Correction of Hemophilia B Phenotype in R333Q Mice.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 5136-5136
Author(s):  
Daniel L. Coutu ◽  
Jessica Cuerquis ◽  
May Griffith ◽  
Mark D. Blostein ◽  
Jacques Galipeau
Keyword(s):  
Gene Therapy ◽  
Mesenchymal Stromal Cells ◽  
Stromal Cells ◽  
Human Factor ◽  
Factor Ix ◽  
Hemophilia B ◽  
Monogenic Disease ◽  
Human Factor Ix ◽  
B Mice

Abstract Hemophilia B is considered an appropriate disease target for gene therapy because it is a well characterized monogenic disease with a large therapeutic index. Despite promising preclinical and clinical trials in the last decade, safety and efficacy concerns associated with the in vivo administration of viral vectors still need to be addressed before gene therapy becomes part of the standard arsenal for clinicians. Our laboratory has developed a cell therapy approach using gene-enhanced autologous Mesenchymal Stromal Cells (MSCs) to deliver a therapeutic plasmatic protein which addresses these safety concerns. In this study, we tested whether MSCs engineered to express human Factor IX (hFIX) can be used to reverse the bleeding phenotype of R333Q hemophilia B mice developed by Stafford et al. We retrovirally engineered MSCs harvested from normal C57Bl/6 to express hFIX. A gene enhanced polyclonal population of MSCs was capable of producing carboxylated and fully active hFIX by in vitro clotting assays. By ELISA, the cells were shown to produce approximately 250ng of hFIX per million cells per 24h. Ten million of these cells were embedded in a collagen I gel matrix and implanted subcutaneously in R333Q hemophilia B mice (n=10). hFIX activity in mouse plasma (test and control groups) were followed weekly by aPTT assays. hFIX activity reached levels as high as 20% normal activity in some animals with an average +/− SEM of 11.2 +/− 2.1 (FIX activity in controls is <1%). The hFIX activity returned to baseline within 4 weeks. In conclusion, we demonstrate that gene-enhanced autologous MSCs can serve as an effective delivery of functional FIX for temporary correction of the hemophilia B phenotype. We hypothesize the presence of GFP co-expression by the implanted MSCs caused their immune rejection and we are currently testing this hypothesis.

scholarly journals Delivery of human factor IX in mice by encapsulated recombinant myoblasts: a novel approach towards allogeneic gene therapy of hemophilia B

Blood ◽  
1996 ◽  
Vol 87 (12) ◽  
pp. 5095-5103 ◽  
Author(s):  
G Hortelano ◽  
A Al-Hendy ◽  
FA Ofosu ◽  
PL Chang
Keyword(s):  
Gene Therapy ◽  
Human Factor ◽  
Ex Vivo ◽  
Cost Effective ◽  
Factor Ix ◽  
Hemophilia B ◽  
Therapy Strategy ◽  
Human 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 approach was assessed by implanting encapsulated mouse myoblasts secreting human factor IX into allogeneic mice. Human factor IX was detected in the mouse plasma for up to 14 days maximally at approximately 4 ng/mL. Antibodies to human factor IX were detected after 3 weeks at escalating levels, which were sustained throughout the entire experiment (213 days). The antibodies accelerated the clearance of human factor IX from the circulation of the implanted mice and inhibited the detection of human factor IX in the mice plasma in vitro. The encapsulated myoblasts retrieved periodically from the implanted mice up to 213 days postimplantation were viable and continued to secrete human factor IX ex vivo at undiminished rates, hence suggesting continued factor IX gene expression in vivo. Thus, this allogeneic gene therapy strategy represents a potentially feasible alternative to autologous approaches for the treatment of hemophilia B.

Sustained and therapeutic levels of human factor IX in hemophilia B mice implanted with microcapsules: key role of encapsulated cells

2006 ◽  
Vol 8 (3) ◽  
pp. 362-369 ◽  
Author(s):  
Jianping Wen ◽  
Andrew Gómez Vargas ◽  
Frederick A. Ofosu ◽  
Gonzalo Hortelano
Keyword(s):  
Human Factor ◽  
Factor Ix ◽  
Hemophilia B ◽  
Encapsulated Cells ◽  
Human Factor Ix ◽  
B Mice

scholarly journals Pharmacokinetics of Human Factor IX in a dog with Severe Hemophilia B.

1977 ◽  
Author(s):  
P.A. Gentry ◽  
A.R. Thompson ◽  
A.W. Forrey
Keyword(s):  
Human Factor ◽  
Numerical Procedure ◽  
Factor Ix ◽  
Hemophilia B ◽  
High Yield ◽  
Severe Hemophilia ◽  
Activity Data ◽  
Human Factor Ix

In preparing a factor IX concentrate with a high yield and low hepatitis and thromboembolic risks, we have tested this material for survival in an in vivo system, the hemophiliac dog. By following the disappearance of radiolabeled, isolated factor IX in addition to the classic clotting assays, data on protein survival and more accurate kinetic parameters were obtained.Crude factor IX concentrate was prepared by batchwise adsorption-elution with DEAE-Sephadex using cryoprecipitate-poor human plasma. Isolated human factor IX was radiolabeled with 125I by chloramine-T without in vitro loss of clotting activity (Thompson, J Clin Invest, in press, 1977). A preparation containing both crude and isolated factor IX was then subjected to filtration (0.22 μm) and lyophilization; clotting and radioactivity were not altered by these steps.Following infusion of the combined preparation into a dog with severe hemophilia B (0% baseline factor IX) 10 post infusion samples were taken over 96 h for determination of radioactivity and factor IX clotting activity. These data were then analyzed by fitting to a two exponential expression using a Marquart non-linear least squares numerical procedure for a two compartment open model. The central volume was 14.5% of the animal’s body weight; the total volume of distribution was 28% with a t 1/2 distribution of 114 min. The t 1/2 elimination was 20 h; the slower phase of elimination (β, or that affected by redistribution) had a t 1/2 of 40 h. Factor IX clotting activity from the crude concentrate closely paralleled radioactivity from the isolated factor IX throughout the 96 h; t 1/2 β was slightly longer from the clotting activity data.

scholarly journals Recombinant human factor IX: replacement therapy, prophylaxis, and pharmacokinetics in canine hemophilia B

Blood ◽  
1996 ◽  
Vol 88 (7) ◽  
pp. 2603-2610 ◽  
Author(s):  
KM Brinkhous ◽  
JL Sigman ◽  
MS Read ◽  
PF Stewart ◽  
KP McCarthy ◽  
...  
Keyword(s):  
Replacement Therapy ◽  
Human Factor ◽  
Factor Ix ◽  
Hemophilia B ◽  
Degree Of Saturation ◽  
Prophylactic Regimen ◽  
Human Factor Ix ◽  
In Vivo Testing ◽  
Recombinant Human Factor Ix

Recombinant human factor IX (rFIX) has been expressed in transduced cultured cell systems since 1985. Because there has been limited in vivo testing of rFIX in hemophilia B subjects, this study was undertaken using the severe hemophilia B canines of the Chapel Hill strain. Three groups of hemophilic dogs received either 50, 100, or 200 IU/kg of rFIX. As a control, a fourth group of hemophilic dogs received 50 IU/kg of a high purity, plasma-derived human FIX (pdFIX). The coagulant and hemostatic effects of rFIX and pdFIX were similar with all comparative dosing regimens. Based on activity data, the elimination half-life of rFIX was 18.9 +/- 2.3 hours and pdFIX was 17.9 +/- 2.1 hours. A prophylactic regimen administering rFIX daily resulted in a continuous therapeutic level of plasma FIX and was accompanied by a two-fold increase in recovery levels by day 5, compared to that observed with administration of a single bolus. The mechanisms of the high to complete recovery of FIX with the prophylactic regimen could depend not only on the degree of saturation of the vascular endothelial binding sites but also on the altered dynamics of the balance of FIX distribution between the intravascular and extravascular compartments. The pharmacokinetic (PK) parameters for rFIX and pdFIX were similar. However, the relative PK values for V1 and V5s of both products on day 5 differed greatly from day 1 and may reflect the changing equilibrium of FIX between compartments with elevated levels of plasma FIX. Neutralizing antihuman FIX antibodies resulting from human FIX antigen being administered to FIX deficient dogs were observed beginning at 14 days. The antigenicity of rFIX and pdFIX appeared to be comparable. Despite the very different procedures used for production of rFIX and pdFIX products, in vivo testing in hemophilia B dogs showed the functional behavior of these products is similar; they are highly effective for replacement therapy and for prophylaxis.

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