Differential Immunodominance of Human and Porcine Factor VIII in Hemophilia A Mice.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 40-40 ◽  
Author(s):  
John F. Healey ◽  
Ernest T. Parker ◽  
Rachel T. Barrow ◽  
Pete Lollar

Abstract Hemophilia A inhibitor patients and patients with acquired hemophilia A recognize immunodominant epitopes in the A2 and C2 domains of human factor VIII (fVIII). Hemophilia A mice also recognize A2 and C2 domain epitopes when immunized with human fVIII using a dosing schedule that mimics clinical use. We compared the immune responses of hemophilia A mice to human and porcine fVIII using a domain specific ELISA. In this assay, monoclonal antibodies are tested against a panel of six single human fVIII domain hybrid human/porcine fVIII molecules that contain the human A1, A2, ap, A3, C1 or C2 domains. With anti-human antibodies, a positive signal with one of the single human domain proteins identifies domain specificity, whereas loss of signal indicates domain specificity of anti-porcine fVIII antibodies. Exon16 (E16) - disrupted hemophilia A mice (n = 3) received six weekly μ10 g/kg intravenous injections of recombinant B-domain deleted human fVIII and a final 25 μg/kg boost. To obtain comparable inhibitor titers, E16 mice (n = 3) received six weekly injections of μ40 g/kg of recombinant B-domain deleted porcine fVIII. Spleens from high titer mice were fused with NS1 mouse myeloma cells and 485 of the resulting hybridomas were analyzed for fVIII domain specificity (Table). Only two hybridomas secreted antibodies specific for the ap domain. Human fVIII elicited a significantly greater number of antibodies to the A2 domain, whereas porcine fVIII elicited a significantly greater number of antibodies to the A1 and A3 domains (p < 0.01, chi square test). The greater number of anti-C2 antibodies to human fVIII was not significant at the 95% confidence level (p = 0.08). The differential immunodominance of human and porcine fVIII epitopes suggests that it may be possible to design a recombinant hybrid human/porcine fVIII molecule that is less immunogenic than human fVIII in the treatment of patients with hemophilia A. Domain Specificity of Anti-FVIII MAbs Mouse ID: Immunogen No. of MAbs A1 A2 A3 C1 C2 CR & MD CR: Cross Reactive MD: Multidomain 1- Human fVIII 95 2 16 2 7 21 23 & 24 2- Human fVIII 126 13 23 1 2 27 39 & 21 3- Human fVIII 54 1 15 2 1 10 9 & 15 4- Porcine fVIII 123 39 7 19 8 16 33 & 0 5- Porcine fVIII 27 13 5 0 0 4 2 & 3 6- Porcine fVIII 60 9 6 12 1 9 13 & 10

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3186-3186
Author(s):  
Peiqing Ye ◽  
Carol H. Miao

Abstract Formation of inhibitory antibodies to transgene product may limit the success of gene therapy especially for the treatment of hemophilia A. The risk of forming inhibitory antibodies against factor VIII depends on multiple factors. Previously we have shown that following naked gene transfer of fifty micrograms of a liver-specific, high-expressing factor VIII plasmid, pBS-HCRHPI-FVIIIA into hemophilia A mice (at least 60 days old), a robust humoral response was induced two weeks post plasmid injection despite of initial high-level gene expression of factor VIII (Ye et al. (2004) Mol. Ther. 10, 117–126). This response completely inhibited the activity of circulating factor VIII although factor VIII was persistently expressed in the liver. In this study, the cytokine production was characterized in human factor VIII-activated T cells from plasmid-treated and untreated hemophilic A mice, consistent with a response predominantly mediated by Th2-induced signals. Injection of plasmid DNA into 4 groups of hemophilia A mice (n=5, 60 days old) with 4 different doses (0.4, 2, 10, & 50 microgram per animal) resulted in vector dose-dependent expression of factor VIII. In addition, the two groups of mice with lower doses of plasmid DNA (0.4 & 2 microgram per animal) did not elicit any antibody response against factor VIII, whereas the two groups of mice with higher doses of plasmid DNA (10 & 50 microgram per animal) induced inhibitory antibody formation. Nevertheless, when the two groups of animals (n=4) with lower doses were treated with second injection of fifty microgram of factor VIII plasmid 180 days post plasmid delivery, all mice developed inhibitors suggesting no immune tolerance was induced by first injection of plasmids. Furthermore, fifty micrograms of factor VIII plasmids were injected into 4 groups of hemophilia A mice (n=5) of 4 different age groups (36, 48, 60 & 72 days). It was found that none of the mice with age 36 days at the time of plasmid injection developed inhibitors, 1/5 mice with age 48 days developed inhibitors, whereas the two groups of mice with age 60 & 72 days all developed high-titer inhibitors. These results indicate that induction of anti-factor VIII antibody following gene therapy is strongly dependent upon the vector dose and age of the animals, which has important implication for developing immunomodulation or other strategies to avoid/eliminate antibody responses.


Blood ◽  
2001 ◽  
Vol 97 (10) ◽  
pp. 3311-3312 ◽  
Author(s):  
Hengjun Chao ◽  
Christopher E. Walsh

Abstract This paper reports loss of human factor VIII (hFVIII) inhibitory antibody in immunocompetent C57BL/6 mice. High-titer anti-hFVIII antibody developed in the mice within 7 to 14 days of intraportal administration of adeno-associated virus (AAV) carrying FVIII that coincided with a reduction in plasma hFVIII antigen. Bethesda titers (&gt; 100 units) persisted relatively unchanged for 9 to 10 months. Unexpectedly, at 10 months after injection of the virus, hFVIII protein (up to 59 ng/mL) was detected in 3 mice at the same time as disappearance of hFVIII inhibitor. The level of hFVIII was similar to that found in immunodeficient mice receiving the same dose of recombinant AAV carrying hFVIII without hFVIII inhibitor. These results suggest that tolerance to hFVIII can be induced by sustained expression of hFVIII in a mouse model. Further elucidation of this observation may affect use of FVIII gene transfer in the treatment of inhibitor-positive patients with hemophilia A.


1996 ◽  
Vol 76 (01) ◽  
pp. 017-022 ◽  
Author(s):  
Sylvia T Singer ◽  
Joseph E Addiego ◽  
Donald C Reason ◽  
Alexander H Lucas

SummaryIn this study we sought to determine whether factor VUI-reactive T lymphocytes were present in hemophilia A patients with inhibitor antibodies. Peripheral blood mononuclear cells (MNC) were obtained from 12 severe hemophilia A patients having high titer inhibitors, 4 severe hemophilia A patients without inhibitors and 5 normal male subjects. B cell-depleted MNC were cultured in serum-free medium in the absence or presence of 2 µg of recombinant human factor VIII (rFVIII) per ml, and cellular proliferation was assessed after 5 days of culture by measuring 3H-thymidine incorporation. rFVIII induced marked cellular proliferation in cultures of 4 of 12 inhibitor-positive hemophilia patients: fold increase over background (stimulation index, SI) of 7.8 to 23.3. The remaining 8 inhibitor-positive patients, the 4 hemophilia patients without inhibitors and the 5 normal subjects, all had lower proliferative responses to rFVIII, SI range = 1.6 to 6.0. As a group, the inhibitor-positive subjects had significantly higher proliferative responses to rFVIII than did the inhibitor-negative and normal subjects (p < 0.05 by t-test). Cell fractionation experiments showed that T lymphocytes were the rFVIII-responsive cell type, and that monocytes were required for T cell proliferation. Thus, rFVIII-reactive T lymphocytes are present in the peripheral circulation of some inhibitor-positive hemophilia A patients. These T cells may recognize FVIII in an antigen-specific manner and play a central role in the regulation of inhibitor antibody production


1966 ◽  
Vol 16 (03/04) ◽  
pp. 559-573 ◽  
Author(s):  
L Uszyński

SummaryRabbits immunized against human AHG fibrinogen-free preparations, were shown to produce anti-AHG antibodies. The inhibitory activity of these antibodies was tested by thromboplastin generation test, thrombelastography, and the specific anti-AHG antibodies neutralization test. The latter test permitted quantitative determination of antigenic form of factor VIII. The inhibitory activity of anti-FI-O-Ta serum resulted exclusively from the anti-AHG antibodies which in coagulation tests behaved like circulating anticoagulants directed against factor VIII.The anti-AHG antibodies were neutralizable by normal human serum or plasma even contained only trace of AHG activity after storage. There was no antigenic form of factor VIII in the severely affected patients with hemophilia A, von Willebrand’s disease nor in the normal plasma adsorbed on bentonite. The presented results suggest a molecular defect of factor VIII in patients with hemophilia A. The severe form of this disease depends, probably, on a major impairment of AHG biosynthesis, leading to changes in the antigenic properties of the molecule. The AHG from rabbit, porcine and bovine plasma respectively did not neutralize the anti-AHG antibodies formed in rabbits immunized against human factor VIII preparations.


2021 ◽  
Vol 100 (2) ◽  
pp. 182-187
Author(s):  
P.A. Zharkov ◽  

Currently, the prophylactic use of factor VIII concentrate is the «gold standard» for treatment of an uncomplicated severe hemophilia A without inhibitors. However, there are a number of difficulties associated with frequent intravenous injections to maintain the activity of factor VIII above 1% in children and adolescents, which cannot but affect the adherence of patients to this type of treatment. The article discusses modern approaches to extend the half-life of recombinant factor VIII allowing to reduce the frequency of infusions and increase the residual activity of the deficient factor. On the example of efmoroctocog alpha, the first recombinant factor VIII concentrate registered in our country with a prolonged half-life, effectiveness and safety data of this class of drugs approved for use in children is presented.


2001 ◽  
Vol 85 (01) ◽  
pp. 125-133 ◽  
Author(s):  
Huiyun Wu ◽  
Mark Reding ◽  
Jiahua Qian ◽  
David Okita ◽  
Ernie Parker ◽  
...  

SummaryMice genetically deficient in factor VIII (fVIII) are a model of hemophilia A. As a first step to reproduce in this mouse model what occurs over time in hemophilia A patients treated with human fVIII (hfVIII), we have investigated the time course and the characteristics of their immune response to hfVIII, after multiple intravenous injections. Anti-hfVIII antibodies appeared after four to five injections. They were IgG1 and to a lesser extent IgG2, indicating that they were induced by both Th2 and Th1 cells. Inhibitors appeared after six injections. CD4+ enriched splenocytes from hfVIII-treated mice proliferated in response to fVIII and secreted IL-10: in a few mice they secreted also IFN-γ and in one mouse IL-4, but never IL-2. A hfVIII-specific T cell line derived from hfVIII-treated mice secreted both IL-4 and IFN-γ, suggesting that it included both Th1 and Th2 cells. CD4+ enriched splenocytes of hfVIII-treated mice recognized all hfVIII domains. Thus, hemophilic mice develop an immune response to hfVIII administered intravenously similar to that of hemophilia A patients. Their anti-hfVIII antibodies can be inhibitors and belong to IgG subclasses homologous to those of inhibitors in hemophilic patients; their anti-hfVIII CD4+ cells recognize a complex repertoire and both Th1 and Th2 cytokines, and especially IL-10, may drive the antibody synthesis. Abbreviations used: antibodies, Ab; antigen presenting cells, APC; Arbitrary Units, AU; enzyme-linked immunosorbant assay, ELISA; factor VIII, fVIII; human factor VIII, hf VIII; intravenous, i.v.; optical density, OD; polymerase chain reaction, PCR; phosphate buffered saline solution, PBS; PBS containing 3% bovine serum albumin, PBS/BSA; PBS containing 0.05% polyoxyethylene sorbitan monolaurate, PBS/Tween-20; phytohemoagglutinin, PHA; stimulation index, SI


2007 ◽  
Vol 10 (23) ◽  
pp. 4299-4302 ◽  
Author(s):  
Habib Onsori ◽  
Mohammad Ali Hossein . ◽  
Sheideh Montaser-Kou . ◽  
Mohammad Asgharzadeh . ◽  
Abbas Ali Hosseinpou .

Blood ◽  
1996 ◽  
Vol 87 (11) ◽  
pp. 4671-4677 ◽  
Author(s):  
S Connelly ◽  
JM Gardner ◽  
RM Lyons ◽  
A McClelland ◽  
M Kaleko

Deficiency of coagulation factor VIII (FVIII) results in hemophilia A, a common hereditary bleeding disorder. Using a human FVIII-encoding adenoviral vector, Av1ALAPH81, we have demonstrated expression of therapeutic levels of human FVIII in mice sustained for more than 5 months after vector administration. Administration of a high dose (4 x 10(9) plaque-forming units [pfu]) of Av1ALAPH81 to mice resulted in a peak expression of 2,063 ng/mL of human FVIII in the mouse plasma, with levels decreasing to background by weeks 15 to 17. Normal FVIII levels in humans range from 100 to 200 ng/mL and therapeutic levels are as low as 10 ng/mL. Alternatively, administration of 8- to 80-fold lower vector doses (5 x 10(8) pfu to 5 x 10(7) pfu) to normal adult mice resulted in expression of FVIII at therapeutic levels sustained for at least 22 weeks. Detailed analysis of vector toxicity indicated that the high vector dose caused a dramatic elevation of liver-specific enzyme levels, whereas an eight-fold lower vector dose was significantly less hepatotoxic. The data presented here demonstrate that administration of lower, less toxic vector doses allow long-term persistence of FVIII expression.


2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Katarzyna A. Jalowiec ◽  
Martin Andres ◽  
Behrouz Mansouri Taleghani ◽  
Albulena Musa ◽  
Martina Dickenmann ◽  
...  

Abstract Background Acquired hemophilia A is a rare autoimmune disease with clinically often significant bleeding diathesis resulting from circulating autoantibodies inhibiting coagulation factor VIII. Half of acquired hemophilia A cases are associated with an underlying disorder, such as autoimmune diseases, cancer, or use of certain drugs, or occur during pregnancy and in the postpartum period. In the other half, no underlying cause is identified. An association of acquired hemophilia A with plasma cell neoplasm seems to be extremely rare. Case presentation We describe a case of a 77-year-old Swiss Caucasian man who was diagnosed with acquired hemophilia A and smoldering multiple myeloma as an underlying cause. Acquired hemophilia A was treated with prednisolone, cyclophosphamide, and immunoadsorption. Extensive workup revealed a plasma cell neoplasm as the only disorder associated with or underlying the acquired hemophilia A. For long-term control of acquired hemophilia A, we considered treatment of the plasma cell neoplasm necessary, and a VRD (bortezomib, lenalidomide, and dexamethasone) regimen was initiated. Due to multiple complications, VRD was reduced to VRD-lite after two cycles. After nine cycles of induction therapy and five cycles of consolidation therapy, the patient is in complete remission of his acquired hemophilia A and very good partial remission of the plasma cell neoplasm. We conducted a literature review to identify additional cases of this rare association and identified 15 other cases. Case descriptions, including the sequence of occurrence of acquired hemophilia A and plasma cell neoplasm , treatment, evolution, and outcome are presented. Discussion and conclusions Our case, together with 15 other cases described in the literature, underscore the possibility of plasma cell neoplasm as an underlying cause of acquired hemophilia A. Physicians should consider including protein electrophoresis, immunofixation, and analysis of free light chains in laboratory diagnostics when treating a patient with acquired hemophilia A. The occurrence of excessive and unexplained bleeding in patients diagnosed with plasma cell neoplasm should raise suspicion of secondary acquired hemophilia A and trigger the request for coagulation tests, particularly in patients treated with immunomodulatory drugs such as thalidomide or lenalidomide. Additionally, early intervention with immunoadsorption can be lifesaving in cases with high-titer factor VIII inhibitors, especially when surgical interventions are necessary.


Blood ◽  
2000 ◽  
Vol 95 (9) ◽  
pp. 2799-2805 ◽  
Author(s):  
Steven S. Fakharzadeh ◽  
Yue Zhang ◽  
Rita Sarkar ◽  
Haig H. Kazazian

To test the hypothesis that factor VIII expressed in the epidermis can correct hemophilia A, we generated transgenic mice in a factor VIII–deficient background that express human factor VIII under control of the involucrin promoter. Mice from 5 transgenic lines had both phenotypic correction and plasma factor VIII activity. In addition to the skin, however, some factor VIII expression was detected in other tissues that have stratified squamous epithelia. To determine whether an exclusively cutaneous source of factor VIII could correct factor VIII deficiency, we grafted skin explants from transgenic mice onto mice that are double knockouts for the factor VIII and RAG-1 genes. Two graft recipients had plasma factor VIII activity of 4% to 20% of normal and improved whole blood clotting compared with factor VIII–deficient mice. Thus, expression of factor VIII from the epidermis can correct hemophilia A mice, thereby supporting the feasibility of cutaneous gene therapy for systemic disease.


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