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Nishiyama A, Ogiwara K, Mizumachi K, Hashimoto N, Takeyama M, Nogami K. Activated partial thromboplastin time-based clot waveform analysis enables measurement of very low levels of factor IX activity in patients with severe hemophilia B. Int J Hematol 2022; 116:778-786. [PMID: 35864291 DOI: 10.1007/s12185-022-03419-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 07/05/2022] [Accepted: 07/07/2022] [Indexed: 11/30/2022]
Abstract
The precise measurement of very low levels of factor IX activity (FIX:C < 1 IU/dL) is essential for understanding clinical severity and risk of inhibitor development in patients with severe hemophilia B (Pw-SHB). However, such measurement sensitivity has not yet been achieved. We aimed to establish a measurement method using clot waveform analysis (CWA). Residual FIX:C by adding anti-FIX monoclonal antibody, FIX:C by adding recombinant (r)FIX to the commercial Pw-SHB plasmas, and FIX:C in our Pw-SHB were determined by CS-2000i™/CS-2400™, followed by analysis of CWA parameters. The presence of anti-FIX antibody in the commercial Pw-SHB plasmas significantly decreased coagulation potential compared to its absence. The addition of rFIX to these innate plasma samples produced significant changes in three parameters upon adding FIX:C at 0.1-1 IU/dL, supporting the presence of trace FIX:C in Pw-SHB. Therefore, appropriate FIX-depleted plasma containing minimum residual FIX:C was chosen from reference curves of FIX:C (0.01-1 IU/dL). Among patients with untreated Pw-SHB, two had FIX:C 0.6-0.7 IU/dL and two had lower than detectable levels using FIX-depleted plasma. One of the latter had detectable trough levels post-rFIX administration. In conclusion, CWA enabled measurement of very low levels of FIX:C using appropriate FIX-deficient plasma.
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Affiliation(s)
- Atsuko Nishiyama
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan
| | - Kenichi Ogiwara
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan.
| | - Kuniyoshi Mizumachi
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan
| | - Naoki Hashimoto
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan
| | - Masahiro Takeyama
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan
| | - Keiji Nogami
- Department of Pediatrics, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan
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2
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Branchini A, Morfini M, Lunghi B, Belvini D, Radossi P, Bury L, Serino ML, Giordano P, Cultrera D, Molinari AC, Napolitano M, Bigagli E, Castaman G, Pinotti M, Bernardi F. F9 missense mutations impairing factor IX activation are associated with pleiotropic plasma phenotypes. J Thromb Haemost 2022; 20:69-81. [PMID: 34626083 PMCID: PMC9298354 DOI: 10.1111/jth.15552] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/06/2021] [Accepted: 10/06/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Circulating dysfunctional factor IX (FIX) might modulate distribution of infused FIX in hemophilia B (HB) patients. Recurrent substitutions at FIX activation sites (R191-R226, >300 patients) are associated with variable FIX activity and antigen (FIXag) levels. OBJECTIVES To investigate the (1) expression of a complete panel of missense mutations at FIX activation sites and (2) contribution of F9 genotypes on the FIX pharmacokinetics (PK). METHODS We checked FIX activity and antigen and activity assays in plasma and after recombinant expression of FIX variants and performed an analysis of infused FIX PK parameters in patients (n = 30), mostly enrolled in the F9 Genotype and PK HB Italian Study (GePKHIS; EudraCT ID2017-003902-42). RESULTS The variable FIXag amounts and good relation between biosynthesis and activity of multiple R191 variants results in graded moderate-to-mild severity of the R191C>L>P>H substitutions. Recombinant expression may predict the absence in the HB mutation database of the benign R191Q/W/K and R226K substitutions. Equivalent changes at R191/R226 produced higher FIXag levels for R226Q/W/P substitutions, as also observed in p.R226W female carrier plasma. Pharmacokinetics analysis in patients suggested that infused FIX Alpha distribution and Beta elimination phases positively correlated with endogenous FIXag levels. Mean residence time was particularly prolonged (79.4 h, 95% confidence interval 44.3-114.5) in patients (n = 7) with the R191/R226 substitutions, which in regression analysis were independent predictors (β coefficient 0.699, P = .004) of Beta half-life, potentially prolonged by the increasing over time ratio between endogenous and infused FIX. CONCLUSIONS FIX activity and antigen levels and specific features of the dysfunctional R191/R226 variants may exert pleiotropic effects both on HB patients' phenotypes and substitutive treatment.
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Affiliation(s)
- Alessio Branchini
- Department of Life Sciences and Biotechnology and LTTA CentreUniversity of FerraraFerraraItaly
| | | | - Barbara Lunghi
- Department of Life Sciences and Biotechnology and LTTA CentreUniversity of FerraraFerraraItaly
| | - Donata Belvini
- Transfusion ServiceHaemophilia Centre and HaematologyCastelfranco Veneto HospitalCastelfranco VenetoItaly
| | - Paolo Radossi
- Oncohematology‐Oncologic Institute of VenetoCastelfranco Veneto HospitalCastelfranco VenetoItaly
| | - Loredana Bury
- Department of Medicine and SurgeryUniversity of PerugiaPerugiaItaly
| | - Maria Luisa Serino
- Haemostasis and Thrombosis CentreUniversity Hospital of FerraraFerraraItaly
| | - Paola Giordano
- Paediatric SectionDepartment of Biomedicine and Human OncologyA. Moro” UniversityBariItaly
| | - Dorina Cultrera
- Haemophilia Regional Reference CenterVittorio Emanuele” University HospitalCataniaItaly
| | | | - Mariasanta Napolitano
- Haematology UnitThrombosis and Haemostasis Reference Regional Center and PROMISE DepartmentUniversity of PalermoPalermoItaly
| | - Elisabetta Bigagli
- Department of Neuroscience, PsychologyDrug Research and Child Health (NEUROFARBA)Section of Pharmacology and ToxicologyUniversity of FlorenceFlorenceItaly
| | - Giancarlo Castaman
- Department of Oncology, Center for Bleeding DisordersCareggi University HospitalFirenzeItaly
| | - Mirko Pinotti
- Department of Life Sciences and Biotechnology and LTTA CentreUniversity of FerraraFerraraItaly
| | - Francesco Bernardi
- Department of Life Sciences and Biotechnology and LTTA CentreUniversity of FerraraFerraraItaly
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3
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Maternal low-level somatic mosaicism of Cys155Tyr of F9 in severe hemophilia B. Blood Coagul Fibrinolysis 2015; 26:866-8. [DOI: 10.1097/mbc.0000000000000234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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4
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Lin PC, Su YN, Liao YM, Chang TT, Tsai SP, Shu HL, Chiou SS. Efficient detection of factor IX mutations by denaturing high-performance liquid chromatography in Taiwanese hemophilia B patients, and the identification of two novel mutations. Kaohsiung J Med Sci 2014; 30:187-93. [PMID: 24656159 DOI: 10.1016/j.kjms.2013.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 08/19/2013] [Indexed: 10/25/2022] Open
Abstract
Hemophilia B (HB) is an X-linked recessive disorder characterized by mutations in the clotting factor IX (FIX) gene that result in FIX deficiency. Previous studies have shown a wide variation of FIX gene mutations in HB. Although the quality of life in HB has greatly improved mainly because of prophylactic replacement therapy with FIX concentrates, there exists a significant burden on affected families and the medical care system. Accurate detection of FIX gene mutations is critical for genetic counseling and disease prevention in HB. In this study, we used denaturing high-performance liquid chromatography (DHPLC), which has proved to be a highly informative and practical means of detecting mutations, for the molecular diagnosis of our patients with HB. Ten Taiwanese families affected by HB were enrolled. We used the DHPLC technique followed by direct sequencing of suspected segments to detect FIX gene mutations. In all, 11 FIX gene mutations (8 point mutations, 2 small deletions/insertions, and 1 large deletion), including two novel mutations (exon6 c.687-695, del 9 mer and c.460-461, ins T) were found. According to the HB pedigrees, 25% and 75% of our patients were defined as familial and sporadic HB cases, respectively. We show that DHPLC is a highly sensitive and cost-effective method for FIX gene analysis and can be used as a convenient system for disease prevention.
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Affiliation(s)
- Pei-Chin Lin
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yi-Ning Su
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Mei Liao
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tai-Tsung Chang
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Shih-Pien Tsai
- Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Hsiu-Lan Shu
- Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Shyh-Shin Chiou
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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5
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Branchini A, Campioni M, Mazzucconi MG, Biondo F, Mari R, Bicocchi MP, Bernardi F, Pinotti M. Replacement of the Y450 (c234) phenyl ring in the carboxyl-terminal region of coagulation factor IX causes pleiotropic effects on secretion and enzyme activity. FEBS Lett 2013; 587:3249-53. [PMID: 23994528 PMCID: PMC3778434 DOI: 10.1016/j.febslet.2013.08.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/09/2013] [Accepted: 08/16/2013] [Indexed: 11/29/2022]
Abstract
Disease-causing missense mutations mainly impair protein biosynthesis and/or function. The p.Y450C mutation in factor IX (FIX) provided a model to study their interplay. The mutation in the carboxyl-terminus impairs both FIX protein secretion and activity. The phenyl group at this relatively conserved position (c234) has a key role. The differential effects have pathophysiological and evolutionary implications.
The interplay between impaired protein biosynthesis and/or function caused by missense mutations, particularly in relation to specific protein regions, has been poorly investigated. As model we chose the severe p.Y450C mutation in the carboxyl-terminal region of coagulation factor IX (FIX) and, by expression of a panel of recombinant variants, demonstrated the key role of the tyrosine phenyl group for both FIX secretion and coagulant activity. Comparison among highly homologous coagulation serine proteases indicate that additive or compensatory pleiotropic effects on secretion and function by carboxyl-terminal mutations produce life-threatening or mild phenotypes in the presence of similarly reduced protein amounts.
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Affiliation(s)
- Alessio Branchini
- Department of Life Sciences and Biotechnology and LTTA Center, University of Ferrara, Ferrara, Italy
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6
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Spectrum of F9 mutations in Chinese haemophilia B patients: identification of 20 novel mutations. Pathology 2012; 44:342-347. [DOI: 10.1097/pat.0b013e328353443d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 10/23/2011] [Accepted: 11/06/2011] [Indexed: 12/30/2022]
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7
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A diagnostic challenge: mild hemophilia B with normal activated partial thromboplastin time. Blood Coagul Fibrinolysis 2010; 21:368-71. [DOI: 10.1097/mbc.0b013e3283367946] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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8
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Borensztajn K, Chafa O, Le Bonniec B, Wajcman H, Reghis A, Fischer AM, Tapon-Bretaudière J. Inherited factor VII deficiency: identification of two novel mutations (A191V and T239P) in the catalytic domain. Thromb Res 2005; 116:115-20. [PMID: 15907525 DOI: 10.1016/j.thromres.2004.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Revised: 11/09/2004] [Accepted: 11/10/2004] [Indexed: 10/26/2022]
Abstract
We describe here five F7 mutations found in four patients without bleeding history, despite constitutional coagulation Factor VII (FVII) deficiency. All five mutations are missense and affect the catalytic domain of FVII (A191T, A191V, T239P, R224Q and M298I). The A191V and T239P mutations are novel and were found in homozygous patients with no clinical bleeding tendency. The patient diagnosed with the A191V mutation had a phenotype corresponding to a moderate type 1 FVII deficiency (FVII:C 4%, FVII:Ag 5%). The T239P mutation was found in a patient with mild type 2 FVII deficiency (FVII:C 25%, FVII:Ag 95%). Novel mutations are both in close vicinity to the charge-stabilizing system of FVII. Modeling studies allow understanding in part the molecular basis for the loss of function.
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Affiliation(s)
- Keren Borensztajn
- INSERM U428, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris V, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
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9
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Enjolras N, Plantier JL, Rodriguez MH, Rea M, Attali O, Vinciguerra C, Negrier C. Two novel mutations in EGF-like domains of human factor IX dramatically impair intracellular processing and secretion. J Thromb Haemost 2004; 2:1143-54. [PMID: 15219198 DOI: 10.1111/j.1538-7836.2004.00756.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We investigated the mechanisms responsible for severe factor IX (FIX) deficiency in two cross-reacting material (CRM)-negative hemophilia B patients with a mutation in the first and second epidermal growth factor (EGF) domains of FIX (C71Y and C109Y, respectively). We have determined the kinetics of mutant FIX biosynthesis and secretion in comparison with wild-type FIX (FIXwt). In transfected cells, FIXwt was retrieved as two intracellular molecular forms, rapidly secreted into the culture medium. One appeared to be correctly N-glycosylated, and corresponded to a form trafficking between the endoplasmic reticulum (ER) and Golgi apparatus. The other corresponded to the mature form, ready to be secreted, exhibiting correct N-glycosylation and sialylation. In contrast, the two mutants, FIXC71Y and FIXC109Y, were not secreted from the cells and did not accumulate intracellularly. Relative to FIXwt, they were retained longer in the ER and were only N-glycosylated. In addition, the intracellular concentration of the FIX mutants increased when ALLN, an inhibitor of cysteine proteases and of the proteasome degradation pathway, was added to the culture medium. Both the FIX mutants and FIXwt were associated in the ER with the 78-kDa glucose-regulated protein (GRP78/BiP) and calreticulin (CRT), though the amount of CRT associated with the two mutants was twice as strong as with FIXwt. These results strongly suggest that chaperone and lectin molecules act in concert to ensure both proper folding of FIXwt and the retention of mutant molecules.
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Affiliation(s)
- N Enjolras
- Laboratoire d'Hémobiologie EA 1508, Faculté de Médecine RTH Laennec, Lyon, France.
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10
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Castaldo G, Nardiello P, Bellitti F, Rocino A, Coppola A, di Minno G, Salvatore F. Denaturing HPLC procedure for factor IX gene scanning. Clin Chem 2003; 49:815-8. [PMID: 12709378 DOI: 10.1373/49.5.815] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Giuseppe Castaldo
- Dipartimento di Biochimica e Biotecnologie Mediche, Università di Napoli "Federico II" and CEINGE-Biotecnologie Avanzate, I-80131 Napoli, Italy
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11
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Castaldo G, Nardiello P, Bellitti F, Santamaria R, Rocino A, Coppola A, di Minno G, Salvatore F. Haemophilia B: from molecular diagnosis to gene therapy. Clin Chem Lab Med 2003; 41:445-51. [PMID: 12747585 DOI: 10.1515/cclm.2003.067] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Thanks to its typical expression, haemophilia can be identified in writings from the second century AD. Haemophilia B, an X-linked recessive bleeding disorder due to factor IX (FIX) deficiency, has an incidence of about 1:30,000 live male births. The factor 9 (F9) gene was mapped in 1984 on Xq27.1. Haemophilia is diagnosed from prothrombin time, activated partial thromboplastin time, and FIX levels. Carrier females are usually asymptomatic and must be identified only with molecular analysis. Linkage analysis of F9 polymorphisms is rapid and inexpensive but limited by non-informative families, recombinant events, and the high incidence of germline mutations; thus, various procedures have been used for the direct scan of F9 mutations. We set up a novel denaturing high performance liquid chromatographic procedure to scan the F9 gene. This rapid, reproducible procedure detected F9 mutations in 100% of a preliminary cohort of 18 haemophilia B patients. Parallel to the development of more efficient diagnostic tools, the life expectancy and reproductive fitness of haemophilic patients have greatly improved and will continue to improve thanks to the use of less immunogenic recombinant FIX. Hopefully, new approaches based on gene therapy now being evaluated in clinical trials will revolutionise haemophilia B treatment.
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Affiliation(s)
- Giuseppe Castaldo
- Dipartimento di Biochimica e Biotecnologie Mediche, Università di Napoli Federico II and CEINGE-Biotecnologie avanzate, Napoli, Italy.
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12
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Hill FGH, Ljung R. Third and fourth Workshops of the European Paediatric Network for Haemophilia Management. Haemophilia 2003; 9:223-8. [PMID: 12614375 DOI: 10.1046/j.1365-2516.2003.00746.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- F G H Hill
- Haematology Department, Birmingham Children's Hospital, Birmingham, UK.
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13
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Abstract
The molecular epidemiology of factor IX germline mutations in patients with hemophilia B has been studied in detail because it is an advantageous model for analyzing recent germline mutations in humans. It is estimated that mutations have been defined in the majority of nucleotides that are the target for mutation. The likelihood that a factor IX missense mutation will cause disease correlates with the degree of evolutionary conservation of the amino acid. Mutation rates per base-pair have been estimated after careful consideration and correction for biases, predicting about 76 de novo mutations per generation per individual resulting in 0.3 deleterious changes. The male-to-female sex ratio of mutation varies with the type of mutation. There is evidence for a maternal age effect and an excess of non-CpG G:C to A:T transitions. The factor IX mutation pattern is similar among geographically, racially and ethnically diverse human populations. The data support primarily endogenous mechanisms of germline mutation in the factor IX gene. Mutations at splice junctions are compatible with simple rules for predicting disease causing mutations.
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Affiliation(s)
- S S Sommer
- Department of Molecular Genetics, Beckman Research Institute, 1450 East Duarte Road, City of Hope, Duarte, CA 91010-0269, USA.
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14
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Ljung R, Petrini P, Tengborn L, Sjörin E. Haemophilia B mutations in Sweden: a population-based study of mutational heterogeneity. Br J Haematol 2001; 113:81-6. [PMID: 11328285 DOI: 10.1046/j.1365-2141.2001.02759.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present series comprises all families (n = 77) with haemophilia B in Sweden and may be considered to be representative for the purposes of a population-based study of mutational heterogeneity. The 77 families (38 severe, 10 moderate, 29 mild) had 51 different mutations in total. Thirteen families had total, partial or small deletions, two had mutations in the promoter, eight families had splice site mutations, 14 had nonsense and the remaining 41 had missense mutations. Ten of the mutations, all C-->T or G-->A, recurred in 1--6 other families. Using haplotype analysis of seven polymorphisms in the factor IX (FIX) gene, we found that the 77 families carried 65 unique, independent mutations. Of the 48 families with severe or moderate haemophilia, 23 (48%) had a sporadic case of haemophilia compared with 31 families out of 78 (40%) in the whole series. Five of those 23 sporadic cases carried de novo mutations, 11 out of 23 of the mothers were proven carriers and, in the remaining seven families, it was not possible to determine carriership. Eleven of the 48 patients (23%) with severe haemophilia B developed inhibitors and all of them had deletions or nonsense mutations. Thus, 11 out of 37 (30%) patients with severe haemophilia B as a result of deletion/nonsense mutations developed inhibitors compared with 0 out of 11 patients with missense mutations. The ratio of male to female mutation rates was 5.3 and the overall mutation rate was 5.4 x 10(-6) per gamete per generation.
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Affiliation(s)
- R Ljung
- Department of Paediatrics, Lund University, University Hospital, Malmö, Sweden.
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