Current status and development trend of coagulation factor Ⅷ activity / 中华检验医学杂志

The detection of coagulation factor Ⅷ activity plays an important role in the diagnosis, typing, efficacy monitoring and detection of inhibitor titer in hemophilia A, acquired hemophilia A and von Willebrand disease. However, due to the diversity of detecting systems, the difference of reagent composition, the existence of interfering substances and other influence factors, the detection of coagulation factor Ⅷ activity in the laboratories in China still needs to be improved.

Clinical application evaluation of chromogenic substrate assay in detecting coagulation factor Ⅷ activity / 中华检验医学杂志

Objective:To establish clinical detection of coagulation factor Ⅷ activity by chromogenic substrate assay and evaluate its clinical application.Methods:A total of 40 hemophilia Apatients, 20 acquired hemophilia A patients, 26 patients with positive lupus anticoagulant and 60 apparently healthy people were enrolled from January 2018 to May 2019 in Ruijin Hospital of Medical College, Shanghai Jiaotong University. According to Clinical and Laboratory Standards Institute(CLSI), the accuracy, within-run and between-run imprecision, lower detection limit, linear range, carryover rate, reference range, and reportable range of chromogenic substrate assay for detecting coagulation factor Ⅷ activity was evaluated, and compared with coagulation assay. The clinical application was evaluated by detecting F Ⅷ activity in acquired hemophilia A patients and patients with lupus anticoagulant by chromogenic substrate assay.Results:The results of two constant quality control products were within range provided by the manufacturer(the bias was 3.93%-6.79%). The within-run imprecision was 1.86%-2.06%(≤5%). The between-run imprecision was 4.83%-6.90%(≤15%). The chromogenic substrate assay had a good performance in sensitivity(CV=11.23%<20%). The recommended reference range was appropriate for our laboratory. The maximum dilution was 1∶16. The linear range was 5.00%-193.50% (a=1.0243, R 2=1.000). The clinical reportable range was 0.50%-387.00%. The method had a low carryover rate (0.04%). The chromogenic substrate assay had good consistency with coagulation assay in detecting coagulation factor Ⅷactivity (R 2=0.961) as well as the titer of FⅧ inhibitor(R 2=0.973).The difference of FⅧ activity in patients with lupus anticoagulant between these two assays was statistically significant(t=9.232,P<0.05). Conclusion:The chromogenic substrate assay has a good performance in clinical detection of coagulation factor Ⅷactivity with wider clinical application and less interference.

Establishment of variables-specific reference ranges of von Willebrand factor antigen and activity / 中国输血杂志

Objective To analyze the screening results of yon Willebrand factor among patients before blood transfusion in Ruijin Hospital and discuss von Willebrand factor in ABO blood group and the relationship between age and gender,refine the classification of vWF antigen and activity by reference factors.Methods The von Willebrand factor among 247 cases of patients before blood transfusion in Ruijin Hospital with no clinical manifestations of abnormal blood clots and routine coagulation as laboratory tests for normal surgical patients.The vWF:Ag and vWF:Act were measured by immune turbidimetric method and ABO blood group was identified by blood type serology.Furthermore,the differences between A,B,O,AB different blood groups,sex and high (≥40 years) and low age group (＜40 years) were compared by statistical methods.Results The levels of vWF:Ag in different blood groups were as follows:A blood type:98.5-142.00,B blood type:97.90-160.30,O blood type:82.13-125.45,A B blood type:103.00-135.80.The levels of vWF:Act in different blood groups were as follows:A blood type:76-130.14,B blood type:78.06-144.3,O blood type:60.89-116.11,AB blood type:88.99-124.09.O blood type vWF:Ag and vWF:Act were lower significantly (P＜0.05) than non-O blood type,the difference was.Besides,young vWF:Ag and vWF:Act were lower significantly than in the elderly.There was no significant difference in vWF:Ag and vWF:Act levels between male and female groups.At last,the reference range of four groups of vWF activity (antigen) was obtained.Conclusion Plasma vWF antigen and activity levels were significantly affected by ABO blood type and age,and the refined reference range established for these influencing factors was beneficial for more detailed diagnosis of VWD and predicting vWF levels associated with bleeding and thrombosis risk.

Identification of genetic defects in a Chinese pedigree with factor XIII deficiency: case report and literature review / 中华血液学杂志

<p><b>OBJECTIVE</b>To perform phenotypic diagnosis, genetic diagnosis and prenatal diagnosis of inherited coagulation factor XIII (FXIII)deficiency in a Chinese family also provide a review of inherited coagulation F XIII deficiency.</p><p><b>METHODS</b>The activity levels of F XIII (F XIII:C) of proband and family members were measured by clot solubility test and REA-chrom F XIII kit. The antigen levels of F XIII(FXIII:Ag) were measured by enzyme-linked immunosorbent assay. Thrombelastography (TEG) test was used to make a comprehensive evaluation of coagulation status in the proband. All 15 exons and exon-intron boundaries of the F13A1 gene were amplified by PCR, and DNA sequencing was performed then. The mutation identified in the proband was screened in the family members. Furthermore, the related literatures were reviewed to provide a profile of clinical manifestation, gene mutations, the relationship between the mutations and phenotype, and treatments of inherited coagulation F XIII deficient cases.</p><p><b>RESULTS</b>The clot solubility test was positive in the proband. The FXIII:Ag level of the proband was less than 1% and the FXIII:C level was below the lower limit of detection (<3%). Two compound heterozygous missense mutations (p.Arg662* and p.Trp665*) were identified in the proband. Family study showed that the two mutations were both inherited from the parents. The fetus also carried two compound heterozygous mutations, the same as the proband, and was diagnosed with severe F XIII deficiency. As reported in the literatures, most mutations were missense mutations and nonsense mutations, and no hot spot was found. The clinical pattern of F XIII deficiency varied among patients, with potentially fatal consequences from severe bleeding complications.</p><p><b>CONCLUSION</b>Better understanding of F XIII biochemical properties and function and developing of FXIII laboratory assays and genetic detection could prevent missed diagnosis, and patients moght benefit from better care.</p>

Compound heterozygous mutations of a family with inherited hypofibrinogenemia / 中华检验医学杂志

Objective To analyze the phenotype and genotype of a Chinese family with inherited hypofibrinogenemia,and to investigate its molecular mechanism.Methods Peripheral blood was collected from seven people of this family and then plasma was separated.Activated partial thromboplastin time ( APTT),prothrombin time ( PT),thrombin time ( TT),reptilase time ( RT),the activities of antithrombin( AT∶ A ),protein C ( PC ∶ A ) and protein S ( PS ∶ A ) were tested.The activity and antigen of plasma fibrinogen were analyzed by Clauss method and immunoturbidimetry method,respectively.The fibrinogen peptide chain of the proband was semiquantitatively assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE).Thrombin generation test was performed by calibrated automated thromhogram.The dynamic process of blood coagulation was evaluated by the thrombelastography (TEG).Genomic DNA was extracted from the peripheral blood.The sequences of all the exons and exon-intron boundaries of the three fibrinogen genes FGA,FGB and FGG were amplified by polymerase chain reaction ( PCR ) and analyzed by direct sequen(c)ing.Results The activity and the antigen levels of the proband' s plasma fibrinogen were reduced to 0.48 g/L and 0.68 g/L,respectively.TT prolonged to 29.2 s and RT prolonged to 75.8 s.The assays of SDS-PAGE showed no abnormal molecular weight of fibrinogen.Peak height of thrombin generation was reduced to 249.93 nmol/L and endogenous thrombin potential was reduced to 1007.0 nmol · L-1 · min.Hypocoagulability state of the whole blood was found by TEG test.The coagulation index was - 8.6.The proband was diagnosed as inherited hypofibrinogenemia by phenotype analysis.Two mutations (Gln143Pro and g.4642delC) were found in the proband's fibrinogen Aa-chain gene,Gln143Pro came from her mother and g.4642delC came form her father.Conclusion Compound Heterozygous Mutations (Gln143Pro and g.4642delC ) of fibrinogen Aa-chain causes the proband congenital hypofibrinogenemia.

The phenotypic and genotypic diagnosis of three Chinese patients with von Willebrand disease / 中华内科杂志

Objective To analyze the phenotype and genotype of three patients with yon Willebrand disease (vWD),and to explore its molecular pathogenesis.Methods Bleeding time (BT),APTT,ristocetin induced platelet aggregation (RIPA),von Willebrand factor (vWF):ristocetin cofactor (Rco)(vWF∶ Rco),vWF antigen (vWF∶ Ag),vWF activity (vWF∶ A) test,vWF collagen binding assay (vWF∶ CB) and multimer analysis were detected for phenotype diagnosis.The dynamic process of blood coagulation was evaluated by using the thrombelastography.Genomic DNA was extracted from the peripheral blood.The vWF gene mutation was detected by sequencing.Results APTT,BT were prolonged in the three probands.Plasma vWF∶ Rco,vWF∶ Ag,vWF∶ A and vWF∶ CB were decreased in different degrees.RIPA was reduced in probands B and C.vWF multimer analysis found the lost of the large molecular weight multimers in proband B,while basically normal in probands A and C.The dynamic process of blood coagulation of proband C presented obvious hypocoagulability by using the thrombelastography.Heterozygous missense mutation g.106782G ＞ T resulting in Cys1130Phe in exon 26,g.110988G ＞ A resulting in Gly1579Arg in exon 28 and g.110373C ＞T resulting in Arg1374Cys in exon 28 were found in the probands A,B and C,respectively.Conclusion Three probands were diagnosed as type 1,type 2A or type 2MvWD by phenotype detection.Heterozygous missense mutation Cys1130Phe,Gly1579Arg and Arg1374Cys induced vWD of three probands,respectively.

Genetic diagnosis of four combined deficiency of factor Ⅴ and Ⅷ patients / 中华检验医学杂志

Objective To investigate the genetic diagnosis and molecular pathogenesis of four patients with combined deficiency of coagulation factor Ⅴ and Ⅷ and their family members. Methods The APPT, FT, FⅤ: C, FⅧ: C were detected for phenotypic diagnosis. Thrombin generation assay was applied to determine the generation condition of thrombin in patients and healthy controls. Cenomic DNA was extracted from peripheral blood using the TianGen RelaxCene Blood DNA System;amniotic fluid DNA was extracted with phenol-ethyl ether method. The LMAN1 and MCFD2 genes were analyzed by PCR. Gene mutations were detected with nucleotid sequences by using end-labeling dideoxy method. Results The APTT of Proband 1 was significantly prolonged to 88. 2s and her PT was prolonged to 19. 6 s. The combined deficiency was identified with FⅧ (FⅧ: C 24. 2% ) and FV(FⅤ: C 9. 1% ). Proband 2 and 3 were sisters. The coagulation studies revealed that both of them had prolonged APTT (71.6 s and 74.6 s respectively) and PT (22. 1 s and 18. 3 s respectively). The combined deficiency of FⅤ (FⅤ: C 7. 6% and 14. 5% respectively) and FⅧ( FⅧ: C 25% and 19.6% respectively) were identified. Proband 4 was detected to have the prolonged APTT (70.3 s),PT (18.2 s) and the deficiency of FⅤ(FⅤ: C 9. 4% ) and FⅧ (15. 7% ). The remaining phenotype indicators test of the 4 probands were normal. The diagnosis for the 4 probands was combined deficiency of factor Ⅴ and Ⅷ. The proband 1 was detected to have compound heterozygous mutations in LMAN1 gene while having the LMAN1 and MCFD2 direct gene sequencing. One mutation was a small insertion located on exon 8 [ nt912insA (X71661. 1)] that resulted in p. 305frameshiftX20 and her mother was detected to have the same heterozygous mutation on the the locus. The other mutation was located on exon 11: nt1366C > CT ( X71661. 1 ) , p. 456Arg > Stop which was inherited from her father. Amniocyte DNA was detected to have only one heterozygous mutaion [nt1366C > CT (X71661. 1) , 456Arg > Stop] inherited from the father. No mutation in MCFD2 gene was found in proband 1 and her parents. The analysis of the MCFD2 gene in proband 2 and 3 revealed a novel homozygous single base substitution (nt411T>C) in exon 4, which results in the exchange of the amino acid isoleucine by the amino acid threonine at amino acid position 136 (p. Ile136Thr). Sequencing of the whole LMAN1 gene showed that the proband 4 had one homozygous nonsence mutation in the exon 5 of the LMAN1 ( nt615C >T,p. 202 Arg> Stop). All of the 4 probands with combined deficiency of FⅤ and FⅧ showed declined endogenous thrombin potential in the thrombin generation tests. Conclusion The combined deficiency of FⅤ and FⅧ in the proband 1 results from the compound heterozygous mutations ( nt1366C > CT and nt912insA) in LMAN1 gene, which are inherited from her parents respectively. The prenatal genetic investigation for the patient mother with preganency indicates that the fetus is a female carrier with one mutation (nt1366C > CT) inherited from the father. The homozygous missence mutation ( nt411T > C, p. Ile136Thr) in the MCFD2 gene accounts for the proband 2 and 3. The daughter of the proband 2 is a carrier with a heterozygous mutation inherited from her mother. The homozygous nonsence mutation in the LMAN1 gene of the proband 4 results in the deficency of F Ⅴ and FⅧ.

Study on the molecular mechanism of the inherited factor X deficiency in three unrelated families / 中华检验医学杂志

Objective To identify the clinical features, the molecular diagnosis and the molecular mechanism of three unrelated factor X deficiency families. Methods Three probands were male and the diagnosis was validated by coagulant parameters. The F X coagulation activity ( F X∶ C ) and antigen (FX∶ Ag) were tested by clotting test and ELISA method. The cross-corrected test was used to rule out the inhibitor of FX in plasma. Thrombin generation test was evaluated. The antigen and the molecule weight of the FX in plasma were measured with western blotting. Gene mutations were analyzed in the probands and their family members with PCR and DNA sequencing. FX expression plasmids were constructed and transientby being transfected into 293T cells. FX: C and FX: Ag of the expression products were tested. Results APTT and PT in proband 1 were obviously prolonged, 113.4 s and 62.3 s, respectively. And there was no inhibitor in plasma. The thrombin generation was lower compared to normal reference. APTT and PT in proband 2 were 56. 5 s and 28.7 s. There was no inhibitor in the plasma. The thrombin generation was 1 101.5 nmol · min. APTT and PT in proband 3 were 117.3 s and 44. 3 s. The thrombin generation was 782.5 nmol · min. FX∶ C and FX∶ Ag in proband 1 were 1.4% and 3.6%, with a homozygous mutation in FX gene (Ser425→Pro). In vitro expression of the mutation showed a normal synthesis in the cell but secretion dysfuntion. In proband 2 F X: C and F X: Ag were 2. 2% and 5. 5%, with two heterozygous mutations in FX gene (Ala-29→Pro and Phe324→Leu). The Ala-29 → Pro mutation led to significantly reduced expressions of FX in both cell lysate and cell culture supernatants compared to wild-type plasmid,(41.32 ±5.21 )% and(6. 30 ± 1.84)% respectively. However Phe324→Leu mutation almost did not affect the FX synthesis. FX: C and FX: Ag in proband 3 were 2. 2% and 35%, with two heterozygous mutations in FX gene( Ala235→Thr and Arg347→Cys). The expressions of these two mutant FX proteins in cell lysate were similar to those of wild-type but obviously lower in the supernatant. Conclusions Five mutations of F X gene are found in this study. These mutations (Ser425Pro, Phe324Leu, Ala235Thr and Arg347Cys)can not affect F X protein synthesis. However Ala-29Pro mutation can reduce F X protein synthesis and cause secretion dysfunction.

Mutation analysis of coagulation factor Ⅺ gene of inherited factor Ⅺ deficiency / 中华检验医学杂志

Ⅺ deficiency in Chinese Han population. Conclusion The 13 mutations of the F Ⅺ gene which were found in this study may unravel the molecular pathogenesis of the F Ⅺ deficiency in Chinese Han population.

Molecular analysis of the genotypes and phenotypes in three pedigrees with inherited antithrombin defidency / 中华检验医学杂志

Objective To investigate the clinical phenotype and genotype in three probands with antithmmbin(AT)deficiency and their families,and to identify the molecular mechanism of AT deficiency.Methods Chromogenic substrate method and immunoturbidimetry assay was used to detect the plasma levels of AT:A and AT:Ag,respectively.Genomic DNA was extracted from the peripheral blood.All 7 exons and the flanking sequences were amplified by PCR.and the abnormal mutant genes were analyzed by direct sequencing.Western blot was used to detect the AT levels and thrombin generation tests were used to detect coagulation status.Results The plasma levels of AT:A and AT:Ag of the three probands declined by 50%.G7386C(Trp225Cys)mutation in exon 4,C2591G(Ser36stop)in exon 2 and C9819T(Arg359stop)in exon 5 were characterized in the three prebands and they could result in W(Trp)225C(Cys)missense mutation,S(Set)36X(stop)nonsense mutation and R(Arg)359X(stop)nonsense mutation respectively,The testing results of phenotype and genotype from some of their family members showed consistent with results from the probands.Western blot results indicated that the Icyels of PC:Ag were lower compared with the normal pooled plasma.The hypercoagulative status was present in the probands using thrombin generation tests.Conclusions Type Ⅰ hereditary AT deficiency was found in these three families.The 3 heterozygous mutations.W225C,S36X and R359X are genetic defects of hereditary AT deficiency.W225C and S36X have not been described before.

Study on hemostatic and coagulative variations during orthotopic liver transplantation / 中华器官移植杂志

Objective To investigate the hemostatic and coagulative variations during orthotopic liver transplantation (OLT).Method The blood platelet count, coagulant and anti-coagulant functions were assessed pre- and intra-operation of OLT.Results During the operation, activated partial thromboplastin time (aPTT) and prothrombin time (PT) were prolonged, platelet count (PLT), activities of most of the coagulation factors and levels of antithrombin (AT), plasminogen (PLG), plasminogen activator inhibitor-1 (PAI-1) and ?2 -antiplasmin (?2-AP) were reduced, while the levels of tissue plasminogen activator (t-PA), plasmin-?2-antiplasmin complex (PAP) and thrombin-antithrombin complex (TAT) were increased. The variations in the neohepatic phase were more significant than that in the pre-operation phase. Conclusion In the entire process of OLT operation, the coagulant and anti-coagulant functions were decreased, and the fibrinolytic functions were sthenic in the anhepatic phase and the neohepatic phase.