scholarly journals Bioengineering hemophilia A–specific microvascular grafts for delivery of full-length factor VIII into the bloodstream

2019 ◽  
Vol 3 (24) ◽  
pp. 4166-4176 ◽  
Author(s):  
Joseph Neumeyer ◽  
Ruei-Zeng Lin ◽  
Kai Wang ◽  
Xuechong Hong ◽  
Tien Hua ◽  
...  

Key Points HA-specific iPSC-derived ECs overexpress full-length F8 after genetic engineering via a piggyBac transposon system. Bioengineered microvascular grafts deliver full-length FVIII into the bloodstream and restore hemostasis in hemophilic SCID mice.

PLoS ONE ◽  
2014 ◽  
Vol 9 (8) ◽  
pp. e104957 ◽  
Author(s):  
Hideto Matsui ◽  
Naoko Fujimoto ◽  
Noriko Sasakawa ◽  
Yasuhide Ohinata ◽  
Midori Shima ◽  
...  

Blood ◽  
2016 ◽  
Vol 127 (19) ◽  
pp. 2289-2297 ◽  
Author(s):  
Andreas Tiede ◽  
Christoph J. Hofbauer ◽  
Sonja Werwitzke ◽  
Paul Knöbl ◽  
Saskia Gottstein ◽  
...  

Key Points This study is the first to assess the prognostic value of FVIII-specific antibody data in patients with AHA. Anti-FVIII IgA, but not immunoglobulin G, autoantibodies at baseline are potential predictors of recurrence and poor outcome of AHA.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4012-4012
Author(s):  
Saulius Butenas ◽  
Behnaz Parhami-Seren ◽  
Matthew T. Gissel ◽  
Edward D. Gomperts ◽  
Kenneth G. Mann

Abstract Several factor VIII products, recombinant and natural, have been used for hemophilia A treatment worldwide. Typically, two activity-based assays (factor Xase and aPTT) are used for the assessment of factor VIII concentration in these products. Frequently, the results are dependent upon the assay and its modifications in different laboratories. In this study, we evaluated five pharmacologic factor VIII products (three lots of each) in three activity-based assays and in two immunoassays for the concentration and activity of factor VIII protein. Two factor VIII products were plasma-derived (Immunate and Hemofil M) and three were recombinant; two of these contained full-length factor VIII (Recombinate and Kogenate) and one was B-domainless (ReFacto). Albumin-free full-length recombinant factor VIII was used as a standard in all assays. In the factor Xase assay, all recombinant factor VIII products and Immunate at 1U/ml (indicated by manufacturer) showed activity similar to that of 0.7nM (1U/ml) standard, whereas activity of Hemofil M was 64–68% of the standard. In the aPTT assay both full-length recombinant products and Hemofil M displayed activity similar to the standard, whereas Immunate had increased (142% of standard) and ReFacto decreased (83% of standard) activity. In synthetic plasma, all three recombinant products had standard-like activity, whereas Hemofil M and Immunate were slightly more active than standard. The ELISA immunoassay revealed that the factor VIII protein content in Recombinate, Kogenate and Hemofil M corresponded to the units assigned by manufacturers (1.4–1.6x1012U/mol vs1.4x1012U/mol calculated for standard), whereas the specific activity of Immunate was 50% of that expected (0.7x1012U/mol). In contrast, the specific activity of ReFacto was almost 3-fold that of full-length factor VIII (4.0x1012U/mol). The data of this study indicate that: 1) factor VIII activity estimated in different assays gives dissimilar results; 2) the specific activity of factor VIII in various factor VIII products is different and, as a consequence, administration of an equal factor VIII activity in U/ml means the administration of different amounts of factor VIII protein.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 238-238 ◽  
Author(s):  
Rebecca C. Markovitz ◽  
John F. Healey ◽  
W. Hunter Baldwin ◽  
Ernest T. Parker ◽  
Shannon L. Meeks ◽  
...  

Abstract The development of neutralizing anti-factor VIII (fVIII) antibodies (inhibitors) remains the most significant complication in the treatment of hemophilia A patients. Treatment of inhibitor patients consists of management of bleeding episodes using bypassing agents or porcine fVIII. Inhibitors can be eradicated by immune tolerance induction (ITI) using thrice-weekly administration of large doses of fVIII. However, ITI fails in approximately 30% of patients. Additionally, the median time to tolerance in successful cases is ~18 months, making ITI expensive and inconvenient. In the current study, we used a murine E16 hemophilia A model to test a novel approach to both prevent and eradicate fVIII inhibitors. We hypothesized that conjugation of fVIII to the toxin saporin, a Type I ribosome-inactivating protein, would target fVIII-specific cell surface immunoglobulin and selectively delete fVIII-specific naïve and memory B cells. Recombinant full-length fVIII was covalently linked to saporin using the heterobifunctional crosslinker N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP). To test for eradication of existing fVIII inhibitors by fVIII-saporin, an adoptive transfer protocol was developed to measure fVIII-specific memory B cells. Hemophilia A donor mice were immunized with 2 μg of full-length fVIII by intravenous injection every other week for 8 weeks, followed by a final dose of 4 μg at ten weeks. Four weeks later, the mice were randomized into three treatment groups to receive equimolar doses of saporin, fVIII, or fVIII-saporin. Seven days after treatment, the mice were sacrificed and 4 x 106 plasma cell CD138+-depleted splenocytes were adoptively transferred as a source of fVIII-specific memory B cells into naïve recipient hemophilia A mice. At 24 hours, recipient mice were given a single injection of 0.5, 1.0 or 2.0 μg of recombinant full-length fVIII by tail vein injection. Anti-fVIII IgG antibodies in recipient mice were measured by ELISA 2 and 5 weeks following the fVIII injection. In the absence of fVIII-specific memory B cells from donor mice, naïve hemophilia A mice did not produce detectable anti-fVIII antibodies. Recipient hemophilia A mice receiving splenocytes from fVIII donor and saporin donor mice displayed a dose-dependent increase in anti-fVIII antibodies. In contrast, the slope of the anti-fVIII titer versus dose of fVIII was significantly decreased in recipient mice receiving splenocytes from fVIII-saporin donor mice. To test for prevention of fVIII inhibitor formation by fVIII-saporin, naïve hemophilia A mice were divided into three treatment groups to receive a single dose of saporin, fVIII, or fVIII-saporin by tail vein injection. Seven days after treatment, the mice were immunized by tail vein injection with 2 μg of full-length fVIII every other week for 10 weeks. Anti-fVIII IgG antibodies were measured 1 week after the fourth and sixth injections of fVIII. Anti-fVIII antibody titers were significantly lower in the fVIII-saporin group compared to the fVIII group (1,900 vs. 21,400 (p=0.027, n=4, Mann-Whitney test, see figure) after the fourth injection. After 6 injections, the average anti-fVIII titer of the fVIII group was 23,000 compared to 4,000 in the fVIII-saporin group (p=0.057, n=4, Mann-Whitney test, see figure). In conclusion, our results suggest that infusion of fVIII-saporin results in the depletion of both fVIII-specific naïve B cells and memory B cells. FVIII-saporin potentially could be used in the treatment of congenital hemophilia A patients with inhibitors and patients with acquired hemophilia A. In addition, fVIII-saporin potentially could be used in previously untreated patients with hemophilia A to prevent inhibitor development. Similar therapeutic strategies could be extended to other antigen-specific immune disorders. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2017 ◽  
Vol 130 (23) ◽  
pp. 2559-2568 ◽  
Author(s):  
Patricia E. Zerra ◽  
Courtney Cox ◽  
W. Hunter Baldwin ◽  
Seema R. Patel ◽  
Connie M. Arthur ◽  
...  

Key Points FVIII colocalizes with MZ B cells following infusion into hemophilia A mice. Depletion of MZ B cells prevents FVIII inhibitor development in hemophilia A mice.


2000 ◽  
Vol 83 (06) ◽  
pp. 811-816 ◽  
Author(s):  
E. Gorina ◽  
E. Kellermann ◽  
E. Vosburgh ◽  
T. C. Abshire ◽  
H.-H. Brackmann ◽  
...  

SummaryTo add an increased level of safety to antihemophilic factor replacement therapy, a full-length, recombinant Factor VIII (rFVIII) product has been developed without human-derived plasma proteins during purification and formulation and using an additional solvent/detergent viral inactivation step. This first clinical trial of a sucrose-formulated full-length rFVIII (rFVIII-FS) was conducted in previously treated patients (≥100 prior exposure days) with severe (<2% FVIII) hemophilia A in North America (NA) and Europe (EU). Pharmacokinetic profiles for rFVIII-FS were compared with those of currently licensed rFVIII product (Kogenate®) in 35 patients. Safety and efficacy during home therapy were evaluated in 71 patients. The new formulation displayed a pharmacokinetic profile similar to that of rFVIII. Patients on home therapy received a cumulative total of 11,867 exposure days, 12,546 infusions, and 22,443,694 IU of rFVIII-FS. Of 2585 bleeds, 93.5% were treated with 1-2 infusions and 80.5% of responses were rated as excellent or good. No evidence of de novo inhibitor formation was observed. Only 0.27% of infusions were associated with any drugrelated adverse event. Except for an episode of intermittent chest pain with palpitations which ceased after treatment with analgesics, associated adverse events were mild or moderate. Overall, rFVIII-FS provided excellent hemostatic control, was well-tolerated, and caused no significant adverse effects, thus demonstrating safety and efficacy for treatment of bleeds in patients with hemophilia A.


Blood ◽  
2015 ◽  
Vol 126 (9) ◽  
pp. 1078-1085 ◽  
Author(s):  
Barbara A. Konkle ◽  
Oleksandra Stasyshyn ◽  
Pratima Chowdary ◽  
David H. Bevan ◽  
Tim Mant ◽  
...  

Key Points BAX 855, a pegylated full-length rFVIII with extended half-life, was highly effective in the prevention and treatment of bleeding events. No subjects receiving BAX 855 developed FVIII inhibitory antibodies nor experienced unexpected adverse events.


2018 ◽  
Vol 2 (14) ◽  
pp. 1792-1798 ◽  
Author(s):  
Nicoletta Machin ◽  
Margaret V. Ragni ◽  
Kenneth J. Smith

Key Points Gene therapy is cost-effective in severe hemophilia A compared with standard factor VIII prophylaxis. Over a 10-year time horizon, gene therapy cost $1M and resulted in 8.33 QALYs gained, whereas prophylaxis cost $1.7M and resulted in 6.62 QALYs gained.


Blood ◽  
2000 ◽  
Vol 95 (5) ◽  
pp. 1594-1599 ◽  
Author(s):  
Hengjun Chao ◽  
Lan Mao ◽  
Andrew T. Bruce ◽  
Christopher E. Walsh

Persistent therapeutic levels of human factor VIII (hFVIII) would signify a major advance in the treatment of hemophilia A. Here we report sustained expression of hFVIII in immunocompetent mice using recombinant adeno-associated virus (rAAV) vectors. AAV can stably transduce liver cells, the target tissue for efficient hFVIII production. Because of rAAV packaging constraints, we tested 2 constructs using small regulatory elements designed for liver-specific transgene expression linked to B-domain–deleted hFVIII (BDD-hFVIII) cDNA. More than 1012/mL rAAV/BDD-hFVIII virion particles were generated using a transfection scheme that eliminates adenovirus. Coatest and APTT assays confirmed the production of functional BDD-hFVIII protein after transduction of 293 and HepG2 cells. In vivo experiments were performed in C57BL/6 and NOD/scid mice receiving 1010–11 rAAV/hFVIII particles via portal vein injection. All C57BL/6 mice tested developed anti-hFVIII antibody. In contrast, NOD/scid mice expressed hFVIII reaching 27% of normal human plasma levels. As expected, we could not detect hFVIII antigen from plasma samples isolated from control animals receiving equivalent doses of rAAV expressing enhanced green fluorescent protein (EGFP). Transgene mRNA expression was detected primarily in the liver and histologic analysis of the liver revealed no pathologic abnormalities. These results demonstrate a promising approach for treatment of hemophilia A.


1999 ◽  
Vol 81 (02) ◽  
pp. 234-239 ◽  
Author(s):  
Sheila Connelly ◽  
Julie Andrews ◽  
Angela Gallo-Penn ◽  
Luigina Tagliavacca ◽  
Randal Kaufman ◽  
...  

SummaryAdenoviral vectors provide a promising gene therapy system for the treatment of hemophilia A. Potent vectors encoding a human factor VIII (FVIII) cDNA were developed that mediated sustained FVIII expression in normal and hemophiliac mice and complete phenotypic correction of the bleeding disorder in hemophiliac mice and dogs (Connelly and Kaleko, Haemophilia 1998; 4: 380-8). However, these studies utilized vectors encoding a truncated version of the human FVIII cDNA lacking the B-domain (BDD FVIII). In this work, an adenoviral vector encoding the human full-length (FL) FVIII cDNA was generated and characterized. While functional FL FVIII was secreted in vitro, expression of the FL protein was not detected in the plasma of vector-treated hemophiliac mice. Unexpectedly, the FL FVIII vector-treated animals demonstrated phenotypic correction of the bleeding defect as measured by a tail-clip survival study. FL FVIII protein was visualized in the mouse livers using human FVIII-specific immunohistochemical analyses. These data demonstrate that adenoviral vector-mediated in vivo expression of BDD FVIII is more efficient than that of the FL protein and that phenotypic correction can occur in the absence of detectable levels of FVIII.


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