Factor VIII deficiency inhibition or abnormal contact

Poster presented at the International Society on Thrombosis and Haemostasis 2015 Congress, 20-25 June 2015, Toronto.

Successful use of recombinant factor VII in massive hemoptysis due to community-acquired pneumonia

Recombinant activated factor VII (rFVIIa) is a powerful hemostatic agent developed for use in hemophilia. It has been used increasingly in life-threatening hemorrhage in a variety of other settings in which conventional medical or surgical therapy is unsuccessful. This report describes the successful use of rFVIIa for pulmonary hemorrhage due to a focal bleeding source in a regional hospital where bronchial artery embolization or surgery were not available. rFVIIa may be a useful temporizing measure in the unstable patient with pulmonary hemorrhage without coagulopathic bleeding when conventional treatment. is not immediately available.

Quantitative correlation between transcriptional levels of ER chaperone, peroximal protein and FVIII productivity in human Hek-293 cell line

Hek-293 cell line presents good production platform for recombinant therapeutic proteins, however little is known about the components that contribute to the cellular control of recombinant protein production. In this study, we generated a Hek-293 producing recombinant factor VIII (FVIII) and we evaluated the immunoglobulin-binding protein (BiP) and phytanoil-CoA α-hydroxylase (PAHX) expression levels which are known for diminishing FVIII production. Our analyses showed that the recombinant cell population expresses 3.1 ± 1.4 fold of BIP mRNA (P = 0.0054) and 97.8 ± 0.5 fold of PAHX mRNA (P = 0.0016) compared to nontransduced cells. The amount of these proteins was inversely correlated to the secreted FVIII. In conclusion, BIP and PAHX expression are augmented in human cells producing FVIII and they antagonize the amount of therapeutic factor VIII in the cell culture.

Transient transfection of serum-free suspension HEK 293 cell culture for efficient production of human rFVIII

Abstract Background Hemophilia A is a bleeding disorder caused by deficiency in coagulation factor VIII. Recombinant factor VIII (rFVIII) is an alternative to plasma-derived FVIII for the treatment of hemophilia A. However, commercial manufacturing of rFVIII products is inefficient and costly and is associated to high prices and product shortage, even in economically privileged countries. This situation may be solved by adopting more efficient production methods. Here, we evaluated the potential of transient transfection in producing rFVIII in serum-free suspension HEK 293 cell cultures and investigated the effects of different DNA concentration (0.4, 0.6 and 0.8 μg/106 cells) and repeated transfections done at 34° and 37°C. Results We observed a decrease in cell growth when high DNA concentrations were used, but no significant differences in transfection efficiency and in the biological activity of the rFVIII were noticed. The best condition for rFVIII production was obtained with repeated transfections at 34°C using 0.4 μg DNA/106 cells through which almost 50 IU of active rFVIII was produced six days post-transfection. Conclusion Serum-free suspension transient transfection is thus a viable option for high-yield-rFVIII production. Work is in progress to further optimize the process and validate its scalability.

Rational combinatorial chemistry-based selection, synthesis and evaluation of an affinity adsorbent for recombinant human clotting factor VII

The selection, synthesis and chromatographic evaluation of a synthetic affinity adsorbent for human recombinant factor VIIa is described. The requirement for a metal ion-dependent immunoadsorbent step in the purification of the recombinant human clotting factor, FVIIa, has been obviated by using the X-ray crystallographic structure of the complex of tissue factor (TF) and Factor VIIa and has directed our combinatorial approach to select, synthesise and evaluate a rationally-selected affinity adsorbent from a limited library of putative ligands. The selected and optimised ligand comprises a triazine scaffold bis-substituted with 3-aminobenzoic acid and has been shown to bind selectively to FVIIa in a Ca2+-dependent manner. The adsorbent purifies FVIIa to almost identical purity (>99%), yield (99%), activation/degradation profile and impurity content (∼1000 ppm) as the current immunoadsorption process, while displaying a 10-fold higher static capacity and substantially higher reusability and durability. © 2002 Elsevier Science B.V. All rights reserved.

Key Issues In Inhibitor Management In Patients With Haemophilia.

12 Suppl 1

Unexpected bleeding following eyelid tumor resection leading to the rare diagnosis of acquired haemophilia.

BACKGROUND: Our goal is to report for the first time in the literature a case of uncontrolled bleeding after an oculoplastic surgical procedure leading to the diagnosis of acquired haemophilia. HISTORY AND SIGNS: An 82-year-old patient underwent tumor excision and reconstruction of his right lower eyelid. On the same day, uncontrolled bleeding occurred that resisted optimal blood pressure control, external compression, surgical haemostasis and wound revision. Usual coagulation screening tests were normal, except for a slightly prolonged activated partial thromboplastin time. THERAPY AND OUTCOME: Extensive coagulation check was performed, which showed a severely reduced factor VIII due to the presence of an inhibitor. The bleeding was immediately stopped after administration of recombinant factor VIIa. After healing of the wound, factor VIIa treatment was replaced by immunosuppressive therapy. The factor VIII inhibitor became unmeasurable and remained so for three months after stopping the immunosuppressive therapy. CONCLUSIONS: Ophthalmologists confronted with unexpected uncontrolled bleeding should think about the possibility of blood dyscrasia, in particular acquired haemophilia.

Tratamiento de sangrado postoperatorio en cirugía cardiaca con Factor VII Recombinante

El sangrado posterior a cirugía cardiaca es una complicación importante dada la alta morbimortalidad asociada. La hemotransfusión es la terapia mandatoria, pero la administración masiva de hemoderivados también es un factor de riesgo independiente de morbimortalidad. El factor VIIr se ha propuesto para disminuir las trasfusiones y controlar sangrado. El propósito de este estudio fue determinar si el factor VIIr es una herramienta útil para disminuir el consumo de hemoderivados en sangrado postoperatorio durante cirugía cardiaca sin riesgo de complicaciones tromboembólicas o falla renal aguda. Es un estudio de cohorte retrospectivo realizado durante dos años, comparando el consumo de hemoderivados y las complicaciones postoperatorias en la cohorte que recibió factor VIIa y en la que no. Se realizó muestreo por comparación de medias emparejadas y se describieron variables cualitativas mediante distribuciones de frecuencias y porcentuales, variables cuantitativas con medidas de tendencia central como promedio y mediana, medidas de dispersión como la desviación estándar. Para determinar normalidad se utilizó prueba Kolgomorov Smirnov con nivel de significancia a=10%; de no cumplir normalidad se utilizaron pruebas t-student y U de Mann-Whitney con nivel de significancia a=5%. Se recolectaron 54 pacientes de los cuales a 14 se les aplicó factor VIIr. Un promedio cinco unidades de glóbulos rojos, nueve de plasma, seis de plaquetas y cuatro de crioprecipitados fueron transfundidas sin diferencias significativas en los grupos. Si se aprecia disminución del sangrado en 24 horas postoperatorias, corrección de los tiempos de coagulación, y menor mortalidad. Las complicaciones tromboembólicas y falla renal no fueron estadísticamente significativas.

Calidad de vida en personas con hemofilia: una revisión de la literatura

Introducción: La hemofilia es una enfermedad poco frecuente; no obstante, los avances en los tratamientos de pacientes hemofílicos en las últimas décadas han generado cambios en su calidad de vida. Esto ha motivado el desarrollo de múltiples investigaciones al respecto. Objetivo: Revisar la literatura sobre la calidad de vida en el paciente hemofílico, producida en el periodo 2008-2012. Método: Se consultaron algunas bases de datos científicas utilizando como palabras clave “hemofilia” y “calidad de vida”. Se recopiló la información encontrada y se organizó según los objetivos propuestos en “factores negativos” y “factores protectores” de la calidad de vida a nivel fisiológico, psicosocial y cultural; “instrumentos para la evaluación de la calidad de vida” a nivel específico y general; y antecedentes empíricos de los últimos cinco años en los que se evaluara la calidad de vida o se realizara alguna intervención en la misma. Resultados: En general la información disponible sobre el comportamiento epidemiológico de la hemofilia es limitada. El interés por factores protectores y negativos es principalmente de tipo fisiológico, aunque se encontraron factores de tipo psicosocial y cultural, lo que indica la importancia de profundizar en esta temática. Existen pocos instrumentos especializados para la evaluación de la calidad de vida en hemofílicos. La evidencia empírica se centra en la evaluación. Conclusión: El estudio de la calidad de vida en pacientes hemofílicos amerita ser abordado de manera interdisciplinaria.

Cyclooxygenase-2 and vascular endothelial growth factor expression in 5-fluorouracil-induced oral mucositis in hamsters: evaluation of two low-intensity laser protocols

The aim of this study was to investigate the mechanisms whereby low-intensity laser therapy may affect the severity of oral mucositis. A hamster cheek pouch model of oral mucositis was used with all animals receiving intraperitoneal 5-fluorouracil followed by surface irritation. Animals were randomly allocated into three groups and treated with a 35 mW laser, 100 mW laser, or no laser. Clinical severity of mucositis was assessed at four time-points by a blinded examiner. Buccal pouch tissue was harvested from a subgroup of animals in each group at four time-points. This tissue was used for immunohistochemistry for cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), and factor VIII (marker of microvessel density) and the resulting staining was quantified. Peak severity of mucositis was reduced in the 35 mW laser group as compared to the 100 mW laser and control groups. This reduced peak clinical severity of mucositis in the 35 mW laser group was accompanied by a significantly lower level of COX-2 staining. The 100 mW laser did not have an effect on the severity of clinical mucositis, but was associated with a decrease in VEGF levels at the later time-points, as compared to the other groups. There was no clear relationship of VEGF levels or microvessel density to clinical mucositis severity. The tissue response to laser therapy appears to vary by dose. Low-intensity laser therapy appears to reduce the severity of mucositis, at least in part, by reducing COX-2 levels and associated inhibition of the inflammatory response.

NUCEL (Cell and Molecular Therapy Center): A multidisciplinary center for translational research in Brazil

Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil`s scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance. To this end, mammalian cell engineering technologies were used to generate cell lines over-expressing several different recombinant proteins of biomedical and biotechnological interest, namely, recombinant human Amylin/IAPP for diabetes treatment, human FVIII and FIX clotting factors for hemophilia, human and bovine FSH for fertility and reproduction, and human bone repair proteins (BMPs). Expression of some of these proteins is also being sought with the baculovirus/insect cell system (BEVS) which, in many cases, is able to deliver high-yield production of recombinant proteins with biological activity comparable to that of mammalian systems, but in a much more cost-effective manner. Transfer of some of these recombinant products to local Biotech companies has been pursued by taking advantage of the Sao Paulo State Foundation (FAPESP) and Federal Government (FINEP, CNPq) incentives for joint Research Development and Innovation partnership projects.

Obtenção e caracterização de anticorpo monoclonal murino anti-fator VIII da coagulação sangüínea

Entre os avanços da engenharia celular e biotecnologia nas últimas décadas, destaca-se a produção de anticorpos monoclonais murinos (AcMm) utilizados no aprimoramento diagnóstico nas rotinas laboratoriais. A produção de fator VIII de alta pureza sempre foi o desejo e a preocupação das indústrias de hemoderivados para tratamento de pacientes portadores de hemofilia A, porém este produto inexiste no Brasil, sendo necessária sua obtenção no mercado internacional a custos elevados. O trabalho tem por objetivo a produção de AcMm anti-fator VIII humano (FVIII H) através da expansão dos clones e caracterização imunoquímica do anticorpo. Camundongos Balb/c foram imunizados com FVIII H purificado como também proveniente de crioprecipitado e as células esplênicas dos animais foram fusionadas com células mielomatosas murinas segundo o método descrito por Kohler e Milstein para produção de híbridos em cultura. Foram testados 1.983 híbridos dos quais 105 foram submetidos à clonagem. Destes, 39 obtiveram monoclonalidade e 7 destes clones foram caracterizados através de técnicas de immunoblotting. Foram submetidas à purificação por cromatografia três imunoglobulinas de diferentes classes pertencentes aos clones LAMB1-10A1A4, LAMB1-17A1A1 e LAMB1-24A2A1. A imunoglobulina purificada pertencente ao clone LAMB1-10A1A4 foi adsorvida em coluna de imunoafinidade para purificação de concentrado de FVIII proveniente de crioprecipitado plasmático.

Ocorrência de inibidores de fator de coagulação em pacientes hemofílicos atendidos no hemocentro regional de Maringá-PR

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Estabilidade do fator de von Willebrand e fator VIII no crioprecipitado canino em diferentes protocolos de armazenamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)