Congenital hemophilia A with low activity of factor XII: a case report and literature review

Background Congenital hemophilia A is a recessive inherited hemorrhagic disorder. According to the activity of functional coagulation factors, the severity of hemophilia A is divided into three levels: mild, moderate and severe. The first bleeding episode in severe and moderate congenital hemophilia A occurs mostly in early childhood and mainly involves soft tissue and joint bleeds. At present, there are limited reports on severe congenital hemophilia A with low factor XII (FXII) activity during the neonatal period. Case presentation A 13-day-old neonate was admitted to the hospital with hematoma near the joints of both upper arms. Coagulation tests showed he had low activity of factor VIII (FVIII) and FXII. He was diagnosed with congenital hemophilia A and treated with human coagulation factor VIII (recombinant FVIII). Although the hematoma became smaller, FVIII activity was only increased to a certain extent and FXII activity decreased gradually. Unfortunately, the child responded poorly to recombinant human coagulation factor VIII and his guardian rejected prophylactic inhibitors and genetic testing and refused further treatment. Three months later, the child developed intracranial hemorrhage (ICH) due to low FVIII activity. Conclusions In hemophilia A, the presence of FVIII inhibitors, drug concentration and testing are three important aspects that must be considered when FVIII activity does not reach the desired level. Early positive disease treatment and prophylaxis can decrease the frequency of bleeding and improve quality of life. We recommend that pregnant women with a family history of hemophilia A undergo early prenatal and neonatal genetic testing.

Novel Coagulation Factor VIII Gene Therapy in a Mouse Model of Hemophilia A by Lipid-Coated Fe3O4 Nanoparticles

Hemophilia A is a bleeding disease caused by loss of coagulation factor VIII (FVIII) function. Although prophylactic FVIII infusion prevents abnormal bleeding, disability and joint damage in hemophilia patients are common. The cost of treatment is among the highest for a single disease, and the adverse effects of repeated infusion are still an issue that has not been addressed. In this study, we established a nonviral gene therapy strategy to treat FVIII knockout (FVIII KO) mice. A novel gene therapy approach was developed using dipalmitoylphosphatidylcholine formulated with iron oxide (DPPC-Fe3O4) to carry the B-domain-deleted (BDD)-FVIII plasmid, which was delivered into the FVIII KO mice via tail vein injection. Here, a liver-specific albumin promoter-driven BDD-FVIII plasmid was constructed, and the binding ability of circular DNA was confirmed to be more stable than that of linear DNA when combined with DPPC-Fe3O4 nanoparticles. The FVIII KO mice that received the DPPC-Fe3O4 plasmid complex were assessed by staining the ferric ion of DPPC-Fe3O4 nanoparticles with Prussian blue in liver tissue. The bleeding of the FVIII KO mice was improved in a few weeks, as shown by assessing the activated partial thromboplastin time (aPTT). Furthermore, no liver toxicity, thromboses, deaths, or persistent changes after nonviral gene therapy were found, as shown by serum liver indices and histopathology. The results suggest that this novel gene therapy can successfully improve hemostasis disorder in FVIII KO mice and might be a promising approach to treating hemophilia A patients in clinical settings.

Characterization and visualization of murine coagulation factor VIII-producing cells in vivo

Coagulation factors are produced from hepatocytes, whereas production of coagulation factor VIII (FVIII) from primary tissues and cell species is still controversial. Here, we tried to characterize primary FVIII-producing organ and cell species using genetically engineered mice, in which enhanced green fluorescent protein (EGFP) was expressed instead of the F8 gene. EGFP-positive FVIII-producing cells existed only in thin sinusoidal layer of the liver and characterized as CD31high, CD146high, and lymphatic vascular endothelial hyaluronan receptor 1 (Lyve1)+. EGFP-positive cells can be clearly distinguished from lymphatic endothelial cells in the expression profile of the podoplanin− and C-type lectin-like receptor-2 (CLEC-2)+. In embryogenesis, EGFP-positive cells began to emerge at E14.5 and subsequently increased according to liver maturation. Furthermore, plasma FVIII could be abolished by crossing F8 conditional deficient mice with Lyve1-Cre mice. In conclusion, in mice, FVIII is only produced from endothelial cells exhibiting CD31high, CD146high, Lyve1+, CLEC-2+, and podoplanin− in liver sinusoidal endothelial cells.

Development of neutralizing antibodies in application of various concentrates of blood coagulation factor VIII in the treatment of hemophilia A

Серьезным осложнением, связанным с лечением гемофилии А, является развитие ингибиторов. В последние годы был проведён ряд исследований, посвящённых данной проблеме: RODIN, INSIGHT, FranceCoag, SIPPET и NuProtect. В данном обзоре суммируются основные результаты этих исследований. Согласно результатам рандомизированного исследования SIPPET, препараты плазматического фактора свертывания крови VIII (FVIII) обладают меньшей иммуногенностью, чем препараты рекомбинантного FVIII, синтезированного из клеточной линии китайских хомячков, что следует учитывать при выборе стратегии лечения. Согласно результатам исследования NuProtect, опубликованным в 2019 г., концентрат рекомбинантного FVIII, полученный из клеточной линии человека, демонстрирует профиль иммуногенности, сходный с таковым у препаратов плазматического FVIII. У ранее нелеченых пациентов с ненулевыми мутациями при применении симоктоког альфа не наблюдалось образования ингибиторов, также как и в случае применения препаратов плазматического FVIII в исследовании SIPPET. Inhibitor development is a serious complication associated with hemophilia A therapy. A number of studies have been carried out of this issue — RODIN, INSIGHT, FranceCoag, SIPPET, and NuProtect. This review summarizes the main results of these studies. According to the results of the SIPPET randomized trial, plasma-derived coagulation factor VIII (FVIII) products are less immunogenic than recombinant FVIII products synthesized from a Chinese hamster cell line; this fact should be taken into account in choosing a treatment strategy. According to the results of NuProtect study published in 2019, the concentrate of human cell line-derived recombinant FVIII demonstrates immunogenicity profi le similar to the one in plasma-derived FVIII products. Previously untreated patients with non-zero mutations receiving simoctocog alfa did not show development of inhibitors as well as in case of administration of plasma-derived FVIII products in SIPPET study.

Protein residue network analysis reveals fundamental properties of the human coagulation factor VIII

Hemophilia A is an X-linked inherited blood coagulation disorder caused by the production and circulation of defective coagulation factor VIII protein. People living with this condition receive either prophylaxis or on-demand treatment, and approximately 30% of patients develop inhibitor antibodies, a serious complication that limits treatment options. Although previous studies performed targeted mutations to identify important residues of FVIII, a detailed understanding of the role of each amino acid and their neighboring residues is still lacking. Here, we addressed this issue by creating a residue interaction network (RIN) where the nodes are the FVIII residues, and two nodes are connected if their corresponding residues are in close proximity in the FVIII protein structure. We studied the characteristics of all residues in this network and found important properties related to disease severity, interaction to other proteins and structural stability. Importantly, we found that the RIN-derived properties were in close agreement with in vitro and clinical reports, corroborating the observation that the patterns derived from this detailed map of the FVIII protein architecture accurately capture the biological properties of FVIII.

APPLICATION OF THE myPKFiT PROGRAM FOR AN INDIVIDUALIZED APPROACH TO PREVENTIVE TREATMENT WITH COAGULATION FACTOR VIII IN CHILDREN WITH HEMOPHILIA A OF THE CHELYABINSK REGION

Для пациентов, получающих лечение препаратом октоког альфа, разработано программное обеспечение (ПО) myPKFiT* на основе web-приложения, позволяющее моделировать режим дозирования с учетом фармакокинетического профиля пациента на основании определения активности F VIII в 2 образцах крови. ПО позволяет изменять (повышать) целевой уровень остаточной активности F VIII, учитывая образ жизни и уровень физической активности пациента. Возможности ПО позволяют наглядно продемонстрировать больному активность FVIII при различных дозах и интервалах введения препарата, а также обозначить риски, возникающие при пропуске приема препарата. Таким образом, myPKFiT решает важную задачу индивидуализированного подхода к подбору и коррекции терапии, способствует улучшению сотрудничества и взаимопонимания врача и пациента, повышению приверженности больного к терапии и достижению оптимальных результатов.