RESUMO
OBJECTIVE: To identify the genetic mutation of coagulation factor â ¦ ( F7) gene in a pedigree with coagulation factor â ¦ (Fâ ¦) deficiency and explore the molecular pathogenesis. METHODS: The prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), D-dimer (DD), fibrin degradation products (FDP) and coagulation factor â ¦ activity (Fâ ¦:C) of the proband and her family members were detected by Sysmex-CS5100 analyzer. All exons and exon-intron boundaries of the F7 gene were amplified by PCR followed by direct sequencing. The detected mutation was confirmed by reverse sequencing. The ClustalW software was used to analyze the conservatism of the mutant site. Pathogenicity of the mutation was assessed with Mutation Taster and PolyPhen-2 online bioinformatics software. Structure of the mutant protein was analyzed using Swiss-PdbViewer software. RESULTS: The results of routine coagulation tests showed that PT of the proband was markedly extended to 42.5 s, and her Fâ ¦:C significantly reduced to 2%. The Fâ ¦:C of her grandmother, mother and sister had slightly reduced to 49%, 51%, and 42%, respectively. These coagulant parameters of her father were within the normal range. Genetic analysis reveled a heterozygous G>A change at cDNA 646 in exon 6 of F7 gene in the proband, resulting in a replacement of glycine at 156 of Fâ ¦ catalytic region with serine (p.Gly156Ser). The sequencing results of other exons and exon-intron boundaries of her F7 gene were normal. The proband's grandmother, mother and sister were all the carriers of this missense mutation except her father. Bioinformatics analysis showed that the p.Gly156Ser mutation caused polarity change of the amino acid at this site and formation of side chains, leading to increase of protein instability, which may affect catalytic activity of structural domain. Meanwhile, both Mutation Taster and PolyPhen-2 online bioinformatics software also predicted the pathogenicity of this missense mutation with high scores. CONCLUSION: The heterozygous p.Gly156Ser mutation is the direct cause of the reduced Fâ ¦ in this proband.
Assuntos
Deficiência do Fator VII , Fator VII , Mutação , Linhagem , Humanos , Feminino , Fator VII/genética , Deficiência do Fator VII/genética , Éxons , Heterozigoto , MasculinoRESUMO
Nonalcoholic fatty liver disease (NAFLD) is considered a risk factor for cardiovascular and cerebrovascular disease owing to its close association with coagulant disturbances. However, the precise biological functions and mechanisms that connect coagulation factors to NAFLD pathology remain inadequately understood. Herein, with unbiased bioinformatics analyses followed by functional testing, we demonstrate that hepatic expression of coagulation factor VII (FVII) decreases in patients and mice with NAFLD/nonalcoholic steatohepatitis (NASH). By using adenovirus-mediated F7-knockdown and hepatocyte-specific F7-knockout mouse models, our mechanistic investigations unveil a noncoagulant function of hepatic FVII in mitigating lipid accumulation and lipotoxicity. This protective effect is achieved through the suppression of fatty acid uptake, orchestrated via the AKT-CD36 pathway. Interestingly, intracellular FVII directly interacts with AKT and PP2A, thereby promoting their association and triggering the dephosphorylation of AKT. Therapeutic intervention through adenovirus-mediated liver-specific overexpression of F7 results in noteworthy improvements in liver steatosis, inflammation, injury, and fibrosis in severely afflicted NAFLD mice. In conclusion, our findings highlight coagulation factor FVII as a critical regulator of hepatic steatosis and a potential target for the treatment of NAFLD and NASH.
Assuntos
Fator VII , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Fator VII/genética , Fator VII/metabolismo , Ácidos Graxos/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
OBJECTIVE: Development of alloantibodies against coagulation factor VII (FVII) is the main therapeutic challenge in severe congenital FVII deficiency. About 7% of patients with severe congenital FVII deficiency develop an inhibitor against FVII. In this research, the relationship between interleukin (IL)-10 and tumor necrosis factor-alpha (TNF)-α gene variants and inhibitor development was evaluated for a group of Iranian patients with severe congenital factor VII deficiency. METHODS: Patients with FVII deficiency were divided into 2 groups: 6 cases and 15 controls. Genotyping was performed using the amplification-refractory mutation system polymerase chain reaction. RESULTS: We found that IL-10 rs1800896 A>G gene variant is associated with the risk of FVII inhibitor development (OR = 0.077, 95% CI = 0.016-0.380, P = .001), whereas the TNFα-rs1800629G>A variant has no relation with inhibitor development in severe FVII deficiency. CONCLUSION: The results show that the IL-10 rs1800896 A>G variant increases the risk of developing an inhibitor in patients with severe congenital FVII deficiency.
Assuntos
Fator VII , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/genética , Fator VII/genética , Interleucina-10/genética , Irã (Geográfico) , IsoanticorposRESUMO
Coagulation factor VII (FVII) deficiency is a congenital disorder with heterogeneous clinical phenotypes ranging from asymptomatic to life-threatening bleeding and/or thrombotic events. We present the case of an adolescent male who developed acute deep and superficial venous thromboses of the upper extremities in the setting of multiple peripheral venous line insertions and shortly after receiving his second coronavirus disease of 2019 immunization dose. A hemostatic work-up revealed low FVII activity levels associated with 4 different FVII genetic variants. We highlight the need to better understand the pathophysiologic mechanisms behind FVII deficiency-associated prothrombotic risk and the role that specific FVII genetic variants may play in the clinical presentation of these patients.
Assuntos
Infecções por Coronavirus , Coronavirus , Deficiência do Fator VII , Trombose , Masculino , Humanos , Deficiência do Fator VII/complicações , Deficiência do Fator VII/genética , Fator VII/genética , ImunizaçãoRESUMO
INTRODUCTION: Inherited Factor VII (FVII) deficiency is commonest among the rare bleeding disorders. A small number of patients present in infancy with severe bleeding, and many may remain asymptomatic but detected before surgery/invasive procedures. Genetic testing may be helpful in predictive testing/prenatal diagnosis in severe cases. AIM: Characterisation of clinical and genotypic spectrum of patients with inherited FVII deficiency. METHODS: Retro-prospectively, 35 cases with prolonged prothrombin time and FVII activity (FVII:C) <50 IU/dl were subjected to targeted resequencing. After in-silico analysis, variant/s were validated by Sanger sequencing in index cases and family members. Haplotype analysis was done for F7 polymorphisms. RESULTS: Severe FVII deficiency was found in 50% of patients (FVII:C ≤1 IU/dl), and 42.9% were asymptomatic. Clinical severity assessment revealed 17% severe, 17% moderate and 22.9% patients with mild bleeds. FVII levels ranged from .3 to 38 IU/dl. Molecular analysis revealed variants in 30/35 cases, of which 17 were homozygous, 10 were compound heterozygous and 3 were heterozygous. Twelve genetic variants were identified, one promoter variant c.-30A>C; seven missense (c.215C>G, c.244T>C, c.253G>C, c.904G>A, c.961C>T, c.1109G>T, c.1211G>A), two deletions (c.21delG, c.868_870delATC), and one each of nonsense c.634C>T and splice-site variant c.316+1G>A. Recurrent variants c.1109G>T and c.215C>G were found in 17 and 8 cases, 12 of the former cases were homozygous. They had the same haplotype, indicating the founder effect in North Indians. CONCLUSION: This is the largest cohort of FVII genotyping from India, confirming heterogeneity in terms of clinical manifestations, FVII activity and zygosity of the variants with a limited genotypic phenotypic correlation.
Assuntos
Transtornos da Coagulação Sanguínea , Deficiência do Fator VII , Humanos , Efeito Fundador , Mutação , Deficiência do Fator VII/diagnóstico , Deficiência do Fator VII/genética , Fator VII/genética , HemorragiaRESUMO
BACKGROUND: Congenital coagulation factor VII (FVII) deficiency is a rare, autosomal-recessive haemorrhagic disorder with an estimated incidence of 1:500,000. This disorder is caused by mutations in the F7 gene. CASE DESCRIPTION: Here, we report a pedigree of congenital FVII deficiency. The proband was a 30-year-old female with severely low FVII activity and a history of menorrhagia and epistaxis since her childhood who was subsequently diagnosed with congenital compound heterozygous FVII deficiency. A genetic study revealed a novel combination of compound heterozygous mutations (c.64G ã A, p.Gly22Ser and c.1027G ã A, p.Gly343Ser). Her father and older son had the c.64G ã A, p.Gly22Ser (heterozygous) mutation. Her mother and younger son had the c.1027G ã A, p.Gly343Ser (heterozygous) mutation. The predicted results of PolyPhen-2 and MutationTaster indicated that these mutations were probably damaging and disease-causing, respectively. CONCLUSION: In this study, we identified a novel combination of genetic mutations that could expand the mutant library and help in elucidating the pathogenesis of hereditary human coagulation FVII deficiency. A novel combination of compound heterozygous mutations was reported for the first time in Chinese individuals.
Assuntos
Transtornos da Coagulação Sanguínea , Deficiência do Fator VII , Humanos , Feminino , Criança , Adulto , Fator VII/genética , Linhagem , População do Leste Asiático , Deficiência do Fator VII/genética , Heterozigoto , Mutação/genéticaRESUMO
RATIONALE: Congenital factor VII deficiency is the most common among rare bleeding disorders, characterized by spontaneous or traumatic bleeding. The clinical manifestation is heterogeneous, ranging from asymptomatic phenotype to life-threatening hemorrhages. Intracranial hemorrhage is a common complication of brain tumor neurosurgery, which significantly challenges the perioperative management of patients with hemostatic defects. PATIENT CONCERNS: This report presented a 55-year-old man with congenital factor VII deficiency, who had no history of hemorrhage or family history. He underwent a craniotomy for the treatment of papillary craniopharyngioma. DIAGNOSES: The patient was diagnosed as papillary craniopharyngioma, factor VII deficiency, and atrial fibrillation. INTERVENTIONS: To prevent bleeding, a total of 8 doses of recombinant activated factor VII and 1 dose of fresh frozen plasma were administered as the perioperative replacement therapy. This scheme was guided by a pharmacodynamic evaluation, laboratory tests, and imaging examinations. OUTCOMES: No excessive surgical bleeding was observed during the 22-day treatment. The patient was found to have compound heterozygous mutations, Ala304Thr (c.910G > A) and IVS5-2A > G (c.572-2A > G), in the F7 gene. LESSONS: This is the first reported case in which surgical hemorrhage secondary to brain tumor resection was successfully controlled in the presence of congenital factor VII deficiency. Perioperative coagulation state, hemostasis, and thrombosis events should be closely observed, and the interval and dosage of recombinant factor VIIa should be adjusted accordingly.
Assuntos
Neoplasias Encefálicas , Craniofaringioma , Deficiência do Fator VII , Neurocirurgia , Neoplasias Hipofisárias , Masculino , Humanos , Pessoa de Meia-Idade , Fator VIIa/uso terapêutico , Deficiência do Fator VII/diagnóstico , Craniofaringioma/complicações , Proteínas Recombinantes/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Hipofisárias/complicações , Plasma , Fator VII/genética , Fator VII/uso terapêuticoRESUMO
Interferon (IFN)-induced protein 35 (IFI35, also known as IFP35), a member of IFN induced genes (ISGs), participates in virus infection, cancer progression and the chronic inflammatory diseases. However, its roles during fish nodavirus infection still remained largely unknown. In the present study, a homolog of IFI35 from orange spotted grouper (Epinephelus coioides) (EcIFI35) was cloned and characterized. The open reading frame of EcIFI35 was composed of 1,128 bp, and encoded a 375 amino acid polypeptide, which contained two conserved N-myc-interactor (Nmi)/IFP35 domains (NIDs). Homology analysis indicated that EcIFI35 shared 95.73% and 31.96% identity with homologs of giant grouper (E. lanceolatus) and human (Homo sapiens), respectively. The transcription of EcIFI35 was significantly up-regulated in grouper spleen (GS) cells after challenged with red-spotted grouper nervous necrosis virus (RGNNV), polyinosinic:polycytidylic acid [poly(I:C)] or lipopolysaccharide (LPS). The subcellular localization analysis showed that EcIFI35 encoded a cytoplasmic protein. The ectopic expression of EcIFI35 inhibited RGNNV replication by reducing viral genes transcription and protein synthesis. Co-immunoprecipitation (Co-IP) assay demonstrated that EcIFI35 interacted with RGNNV coat protein (CP), and partly co-localized with CP. EcIFI35 overexpression promoted the expression of IFN-related molecules and pro-inflammatory factors, including IFN regulatory factor 7 (IRF7), mitochondrial antiviral signaling protein (MAVS) and myxovirus resistance gene I (MxI), nuclear factor κB (NF-κB), interleukin 6 (IL-6) and IL-8. Together, our results revealed that EcIFI35 interacted with CP and inhibited fish nodavirus replication through positively regulated host innate immune response.
Assuntos
Bass , Infecções por Vírus de DNA , Doenças dos Peixes , Nodaviridae , Sequência de Aminoácidos , Aminoácidos/metabolismo , Animais , Antivirais , Fator VII/genética , Fator VII/metabolismo , Proteínas de Peixes/química , Regulação da Expressão Gênica , Humanos , Imunidade Inata/genética , Interferons/metabolismo , Interleucina-6/genética , Interleucina-8/genética , Lipopolissacarídeos , NF-kappa B/metabolismo , Nodaviridae/fisiologia , Poli I-C/farmacologia , Alinhamento de SequênciaRESUMO
OBJECTIVE: Spinocerebellar ataxia with axonal neuropathy type 3 (SCAN3) is a very rare autosomal recessive hereditary disease. Mutations in the COA7 gene, which encodes cytochrome c oxidase assembly factor 7, have been recently reported as the causative gene of SCAN3. So far, only five SCAN3 patients with COA7 mutations have been documented. Herein, we report the clinical, electrophysiological, histological, and genetic findings of a Chinese patient with SCAN3. MATERIALS AND METHODS: The patient was a 31-year-old woman who presented with early-onset peripheral neuropathy and progressive ataxia. She was asked about her medical history and underwent electrophysiological examination, nerve and muscle biopsy, and gene detection. RESULTS: Whole exome next-generation sequencing identified a novel compound heterozygous mutation of COA7 (c.17A>G p.D6G; c.554G>A, p.W185*) in this patient. Magnetic resonance imaging showed cerebellum and spinal cord atrophy. Nerve conduction studies and sural nerve biopsies revealed sensorimotor axonal neuropathy. Muscle biopsies showed mitochondrial abnormalities. Respiratory chain enzyme assay of skin fibroblasts showed normal respiratory chain complex activities. Additionally, the clinical data on previously reported SCAN patients with identified genetic causes in PubMed was summarized. Compared with SCAN1 and SCAN2 patients, SCAN3 patients had earlier onset age, less cognitive impairment, and no ocular signs. CONCLUSION: We reported the first patient diagnosed with SCAN3 in China. A novel mutation in the gene COA7 (c.554G>A, p.W185*) expanded the genetic spectrum of the disease.
Assuntos
Doenças do Sistema Nervoso Periférico , Ataxias Espinocerebelares , Adulto , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fator VII/genética , Feminino , Humanos , Mutação , Linhagem , Doenças do Sistema Nervoso Periférico/genética , Ataxias Espinocerebelares/genéticaRESUMO
BACKGROUND: Congenital factor VII (FVII) deficiency is a rare inherited autosomal recessive disorder characterized by prolongation of prothrombin time and low FVII coagulation activity, which may increase the risk of bleeding. CASE PRESENTATION: A 66-year-old man with acute postoperative intracranial hemorrhage was transferred to our hospital owing to coagulation dysfunction. In coagulation tests, the FVII coagulation activity was less than 2%. Genetic analysis of the gene encoding FVII identified compound heterozygous mutations: c. 681+1 G>T and c. C1286T (p. Ala429Val). CONCLUSIONS: To our knowledge, this is the first report describing the c. C1286T (p. Ala429Val) mutation in the FVII-encoding gene. We suggest that these mutations resulted in the reduced FVII activity and abnormal clotting in our patient after brain surgery.
Assuntos
Deficiência do Fator VII , Idoso , Fator VII/genética , Deficiência do Fator VII/complicações , Deficiência do Fator VII/genética , Heterozigoto , Humanos , Masculino , Mutação/genética , Tempo de ProtrombinaRESUMO
Factor VII (FVII) deficiency is a rare bleeding disorder normally caused by homozygous and compound heterozygous mutations in the F7 gene. Whole-exome sequencing was performed to identify F7 mutations in 3 individuals from 2 unrelated families who were diagnosed with FVII deficiency. Four compound heterozygous mutations were identified and validated in these 3 probands with FVII deficiency. Among the 4 identified mutations, NM_000131.4:c.572-1_581del, NM_000131.4:c.1250A>G (p.Tyr417Cys), and NM_000131.4:c.647G>T (p.Gly216Val) were novel. All 3 novel mutations were predicted to be likely pathogenic by the American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines.
Assuntos
Deficiência do Fator VII/patologia , Fator VII/genética , Heterozigoto , Mutação , Adolescente , Criança , Deficiência do Fator VII/congênito , Deficiência do Fator VII/genética , Família , Feminino , Humanos , Masculino , PrognósticoRESUMO
Factor VII deficiency is the most common of the rare coagulation deficiencies. A hemorrhagic syndrome may occur in patients with FVII deficiency below 20%, although no correlation exist between the plasma FVII activity level (FVII:C) and the bleeding risk. Therefore, the management of surgery in patients with FVII deficiency remains challenging. Laboratory monitoring of FVII:C level may be helpful but should be interpreted with caution, because the dosage of FVII:C level may vary depending on the origin of the thromboplastin used. Herein, we report the case of the management of a woman who had been fortuitously diagnosed during pregnancy with FVII deficiency due to FVII variant Padua, which have induced discrepant results between two different laboratories.
Assuntos
Deficiência do Fator VII/diagnóstico , Deficiência do Fator VII/genética , Fator VII/genética , Fator VII/metabolismo , Complicações Hematológicas na Gravidez/diagnóstico , Tromboplastina/metabolismo , Adulto , Substituição de Aminoácidos , Coagulação Sanguínea/genética , Testes de Coagulação Sanguínea , Fator VII/análise , Deficiência do Fator VII/sangue , Feminino , Humanos , Achados Incidentais , Recém-Nascido , Mutação de Sentido Incorreto , Gravidez , Complicações Hematológicas na Gravidez/genética , Tromboplastina/análiseRESUMO
Circulating miRNAs (c-miRNAs) are promising biomarkers for HF diagnosis and prognosis. There are no studies on HF pediatric patients undergoing VAD-implantation. Aims of this study were: to examine the c-miRNAs profile in HF children; to evaluate the effects of VAD on c-miRNAs levels; to in vitro validate putative c-miRNA targets. c-miRNA profile was determined in serum of HF children by NGS before and one month after VAD-implant. The c-miRNA differentially expressed were analyzed by real time-PCR, before and at 4 hrs,1,3,7,14,30 days after VAD-implant. A miRNA mimic transfection study in HepG2 cells was performed to validate putative miRNA targets selected through miRWalk database. Thirteen c-miRNAs were modified at 30 days after VAD-implant compared to pre-VAD at NSG, and, among them, six c-miRNAs were confirmed by Real-TimePCR. Putative targets of the validated c-miRNAs are involved in the hemostatic process. The in vitro study confirmed a down-regulatory effect of hsa-miR-409-3p towards coagulation factor 7 (F7) and F2. Of note, all patients had thrombotic events requiring pump change. In conclusion, in HF children, the level of six c-miRNAs involved in the regulation of hemostatic events changed after 30 days of VAD-treatment. In particular, the lowering of c-miR-409-3p regulating both F7 and F2 could reflect a pro-thrombotic state after VAD-implant.
Assuntos
MicroRNA Circulante/sangue , Insuficiência Cardíaca/terapia , Coração Auxiliar/efeitos adversos , Trombose/diagnóstico , Biomarcadores/sangue , Pré-Escolar , MicroRNA Circulante/agonistas , MicroRNA Circulante/metabolismo , Biologia Computacional , Regulação para Baixo , Fator VII/genética , Feminino , Perfilação da Expressão Gênica , Insuficiência Cardíaca/sangue , Células Hep G2 , Humanos , Lactente , Masculino , MicroRNAs/agonistas , MicroRNAs/sangue , MicroRNAs/metabolismo , Projetos Piloto , Prognóstico , Protrombina/genética , Reação em Cadeia da Polimerase em Tempo Real , Trombose/sangue , Trombose/etiologiaRESUMO
OBJECTIVE: To detect potential mutations of the coagulation factor â ¦ (F7) gene in a pedigree affected with hereditary Fâ ¦ deficiency and explore its molecular pathogenesis. METHODS: The Fâ ¦ antigen (Fâ ¦:Ag) was analyzed by an enzyme-linked immunosorbent assay (ELISA) method. Prothrombin time (PT), Fâ ¦ activity (Fâ ¦:C) and other coagulant parameters were quantified with an one-stage clotting assay. The F7 gene was amplified by PCR and sequenced. Mutational sites were confirmed by reverse sequencing. Impact of amino acid substitution was assessed using SIFT and PolyPhen-2 software. Structure of the mutant protein was analyzed using Swiss-pdb Viewer software based on the three-dimensional structure in the Protein Data Bank. RESULTS: The propositus had prolonged PT (36.3 s), with Fâ ¦:C and Fâ ¦:Ag significantly reduced to 2% and 44%, respectively. Her father, mother, younger sister and daughter had slightly prolonged PT and reduced Fâ ¦:C (86%-120%). The Fâ ¦:Ag of her father and younger sister were also reduced. DNA sequencing revealed that the propositus has carried compound heterozygous mutations (Lys341Glu and IVS6-1G>A) of the F7 gene. Her father and younger sister were heterozygous for the IVS6-1G>A mutation, while her mother and daughter were heterozygous for the Lys341Glu mutation. Bioinformatics analysis indicated that Lys341Glu mutation may affect the stability and function of the Fâ ¦ protein. CONCLUSION: The Lys341Glu and IVS6-1G>A mutations probably underlie the reduced activity of Fâ ¦ in this pedigree.
Assuntos
Deficiência do Fator VII/genética , Fator VII/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , Masculino , Mutação , LinhagemRESUMO
Infections caused by drug-resistant "superbugs" pose an urgent public health threat due to the lack of effective drugs; however, certain mammalian proteins with intrinsic antibacterial activity might be underappreciated. Here, we reveal an antibacterial property against Gram-negative bacteria for factors VII, IX and X, three proteins with well-established roles in initiation of the coagulation cascade. These factors exert antibacterial function via their light chains (LCs). Unlike many antibacterial agents that target cell metabolism or the cytoplasmic membrane, the LCs act by hydrolyzing the major components of bacterial outer membrane, lipopolysaccharides, which are crucial for the survival of Gram-negative bacteria. The LC of factor VII exhibits in vitro efficacy towards all Gram-negative bacteria tested, including extensively drug-resistant (XDR) pathogens, at nanomolar concentrations. It is also highly effective in combating XDR Pseudomonas aeruginosa and Acinetobacter baumannii infections in vivo. Through decoding a unique mechanism whereby factors VII, IX and X behave as antimicrobial proteins, this study advances our understanding of the coagulation system in host defense, and suggests that these factors may participate in the pathogenesis of coagulation disorder-related diseases such as sepsis via their dual functions in blood coagulation and resistance to infection. Furthermore, this study may offer new strategies for combating Gram-negative "superbugs".
Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Fator IX/farmacologia , Fator VII/farmacologia , Fator X/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/fisiologia , Animais , Antibacterianos/farmacologia , Cromatografia Líquida de Alta Pressão , Fator IX/genética , Fator IX/metabolismo , Fator VII/genética , Fator VII/metabolismo , Fator X/genética , Fator X/metabolismo , Bactérias Gram-Negativas/fisiologia , Células Hep G2 , Humanos , Lipídeo A/análise , Lipídeo A/metabolismo , Lipopolissacarídeos/análise , Lipopolissacarídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Human mesenchymal stem cells (hMSCs) have the potential to differentiate into hepatocyte-like cells, indicating that these cells may be the new target cell of interest to produce biopharmaceuticals. Our group recently established a hMSC-derived immortalized hepatocyte-like cell line (imHC) that demonstrates several liver-specific phenotypes. However, the ability of imHC to produce coagulation factors has not been characterized. Here, we examined the potential for imHC as a source of coagulation protein production by investigating the ability of imHC to produce human factor VII (FVII) using a lentiviral transduction system. Our results showed that imHC secreted a low amount of FVII (~22 ng/mL) into culture supernatant. Moreover, FVII from the transduced imHC (0.11 ± 0.005 IU/mL) demonstrated a similar coagulant activity compared with FVII from transduced HEK293T cells (0.12 ± 0.004 IU/mL) as determined by chromogenic assay. We demonstrate for the first time, to the best of our knowledge, that imHC produced FVII, albeit at a low level, indicating the unique characteristic of hepatocytes. Our study suggests the possibility of using imHC for the production of coagulation proteins.
Assuntos
Fator VII/genética , Técnicas de Transferência de Genes , Hepatócitos/metabolismo , Lentivirus/genética , Linhagem Celular , Fator VII/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução GenéticaRESUMO
Factor VII (FVII) is a key serine protease in blood coagulation. N-glycosylation in FVII has been shown to be critical for protein secretion. To date, however, the underlying biochemical mechanism remains unclear. Recently, we found that N-glycans in the transmembrane serine protease corin are critical for calnexin-assisted protein folding and extracellular expression. In this study, we tested the hypothesis that N-glycans in the FVII protease domain mediate calnexin-assisted protein folding and that naturally occurring F7 mutations abolishing N-glycosylation impair FVII secretion. We expressed human FVII wild-type (WT) and mutant proteins lacking one or both N-glycosylation sites in HEK293 and HepG2 cells in the presence or absence of a glucosidase inhibitor. FVII expression, secretion and binding to endoplasmic reticulum chaperones were examined by immune staining, co-immunoprecipitation, Western blotting, and ELISA. We found that N-glycosylation at N360 in the protease domain, but not N183 in the pro-peptide domain, of human FVII is required for protein secretion. Elimination of N-glycosylation at N360 impaired calnexin-assisted FVII folding and secretion. Similar results were observed in WT FVII when N-glycan-calnexin interaction was blocked by glucosidase inhibition. Naturally occurring F7 mutations abolishing N-glycosylation at N360 reduced FVII secretion in HEK293 and HepG2 cells. These results indicate that N-glycans in the FVII protease domain mediate calnexin-assisted protein folding and subsequent extracellular expression. Naturally occurring F7 mutations abolishing N-glycosylation in FVII may impair this mechanism, thereby reducing FVII levels in patients.
Assuntos
Calnexina/metabolismo , Retículo Endoplasmático/metabolismo , Deficiência do Fator VII/metabolismo , Fator VII/metabolismo , Polissacarídeos/metabolismo , Calnexina/genética , Fator VII/genética , Deficiência do Fator VII/genética , Variação Genética , Glicosilação , Células HEK293 , Células Hep G2 , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação , Dobramento de ProteínaRESUMO
Interaction between the transcription factors, hypoxia-inducible factor (HIF1α and HIF2α) and Sp1, mediates hypoxia-driven expression of FVII gene encoding coagulation factor VII (fVII) in ovarian clear cell carcinoma (CCC) cells. This mechanism is synergistically enhanced in response to serum starvation, a condition possibly associated with tumor hypoxia. This transcriptional response potentially results in venous thromboembolism, a common complication in cancer patients by producing procoagulant extracellular vesicles (EVs). However, which deficient serum factors are responsible for this characteristic transcriptional mechanism is unknown. Here, we report that cholesterol deficiency mediates synergistic FVII expression under serum starvation and hypoxia (SSH) via novel sterol regulatory element binding protein-1 (SREBP1)-driven mechanisms. Unlike conventional mechanisms, SREBP1 indirectly enhances FVII transcription through the induction of a new target, glucocorticoid-induced leucine zipper (GILZ) protein. GILZ expression induced in response to hypoxia by a HIF1α-dependent mechanism activates SREBP1 under SSH, suggesting reciprocal regulation between SREBP1 and GILZ. Furthermore, GILZ binds to the FVII locus. Xenograft tumor samples analyzed by chromatin immunoprecipitation confirmed that HIF1α-aryl hydrocarbon nuclear translocator and GILZ bind to the TSC22D3 (GILZ) and FVII gene loci, respectively, thereby potentially modulating chromatin function to augment FVII transcription. Thus, deficiency of both O2 and cholesterol, followed by interplay between HIFs, Sp1, and SREBP1-GILZ pathways synergistically induce fVII synthesis, resulting in the shedding of procoagulant EVs.
Assuntos
Micropartículas Derivadas de Células/metabolismo , Coagulantes/metabolismo , Fator VII/genética , Hipóxia/metabolismo , Neoplasias Ovarianas/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Colesterol/metabolismo , Montagem e Desmontagem da Cromatina , Fator VII/metabolismo , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Soro/metabolismo , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: To investigate the prevalence of thrombotic events among patients with proven or highly probable homozygosis for the Arg304Gln (Factor VII Padua) defect or compound heterozygosis containing the Arg304Gln mutation. METHODS: Homozygotes and compound heterozygotes proven by molecular studies to have the Arg304Gln mutation were gathered from personal files and from two PubMed searches. In addition, patients with probable homozygosis on the basis of clotting tests (discrepancies among Factor VII activity levels according to the tissue thromboplastin used) were also gathered. RESULTS: 30 proven homozygotes and 17 probable ones were gathered together with 8 compound heterozygotes. In the latter use, the associated mutation was Cys135Arg (twice), Gly180Arg, Arg304Trp, Arg315Trp, His348Gln, Gly365Cys. The prevalence of venous thrombotic events was 16.6, 11.8 and 11.1 percent, respectively for the three groups of patients. Heterozygotes showed no thrombotic event. The difference for proven homozygotes was statistically significant, while for the other groups only a trend was present. CONCLUSION: proven homozygous or compound heterozygous patients with the Arg304Gln mutation showed a higher than expected incidence of thrombotic events. The same is true for probable cases gathered only on the basis of clotting tests. These patients, because of their frequent lack of bleeding and for their relatively high prevalence of thrombosis should probably receive only limited replacement therapy in case of surgical procedures.
Assuntos
Fator VII/genética , Trombose/genética , Adulto , Coagulação Sanguínea , Pré-Escolar , Feminino , Heterozigoto , Homozigoto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Trombose/sangue , Trombose/epidemiologia , Trombose/terapiaRESUMO
Factor VII (FVII) is an important component of the coagulation cascade. Few genetic loci regulating FVII activity and/or levels have been discovered to date. We conducted a meta-analysis of 9 genome-wide association studies of plasma FVII levels (7 FVII activity and 2 FVII antigen) among 27 495 participants of European and African ancestry. Each study performed ancestry-specific association analyses. Inverse variance weighted meta-analysis was performed within each ancestry group and then combined for a trans-ancestry meta-analysis. Our primary analysis included the 7 studies that measured FVII activity, and a secondary analysis included all 9 studies. We provided functional genomic validation for newly identified significant loci by silencing candidate genes in a human liver cell line (HuH7) using small-interfering RNA and then measuring F7 messenger RNA and FVII protein expression. Lastly, we used meta-analysis results to perform Mendelian randomization analysis to estimate the causal effect of FVII activity on coronary artery disease, ischemic stroke (IS), and venous thromboembolism. We identified 2 novel (REEP3 and JAZF1-AS1) and 6 known loci associated with FVII activity, explaining 19.0% of the phenotypic variance. Adding FVII antigen data to the meta-analysis did not result in the discovery of further loci. Silencing REEP3 in HuH7 cells upregulated FVII, whereas silencing JAZF1 downregulated FVII. Mendelian randomization analyses suggest that FVII activity has a positive causal effect on the risk of IS. Variants at REEP3 and JAZF1 contribute to FVII activity by regulating F7 expression levels. FVII activity appears to contribute to the etiology of IS in the general population.