The present study was aimed to investigate the molecular mechanisms responsible for the pathogenesis of severe factor XIII (FXIII) deficiency. Site-directed mutagenesis was conducted to obtain human FXIIIA expression plasmids bearing the mutations. Wild type FXIIIA recombinant plasmid (pcDNA3.1-FXIIIA-wt) and 2 mutant FXIIIA recombinant plasmids (pcDNA3.1/FXIIIA/77mut, pcDNA3.1/FXIIIA/174mut) were transfected into the cultured COS-7 cells using lipofectamine 2000 transfection reagent, respectively. FXIII activities were measured by the Berichrom(®) FXIII chromogenic assay. The expression levels of FXIIIA mRNA were detected by real-time RT-PCR. The recombinant FXIIIA mutants were determined by using Western blot and ELISA. The results showed that the normalized mRNA levels of 2 mutants in transfected COS-7 cells were 0.82 ± 0.21 and 0.76 ± 0.17, respectively. The relative levels of both mRNA transcripts were not significantly decreased as compared with the wild type (1.06 ± 0.51). FXIII activity and FXIIIA antigen levels in concentrated media of cell expressing the wild type protein were (24.0 ± 2.9)% and (13.2 ± 2.3)%, respectively. FXIII activity and FXIIIA antigen levels in cell lysates containing the wild type recombinant protein were (61.6 ± 30.4)% and (32.8 ± 14.5)%, respectively. However, the antigen levels and activity of 2 mutants were severely decreased as compared to the wild type. It is concluded that both mutations severely disturb the normal expression of FXIIIA protein. The reduction of expression levels and decreased activities of the 2 mutants provides a convincible explanation for the deficiency phenotype in the index case.
Animals ; COS Cells ; Cercopithecus aethiops ; Codon, Nonsense ; Factor XIII Deficiency ; genetics ; Factor XIIIa ; genetics ; Genotype ; Humans ; Mutagenesis, Site-Directed ; Mutation, Missense ; Reverse Transcriptase Polymerase Chain Reaction

Humans ; Factor XIII/genetics* ; Factor XIII Deficiency/genetics* ; Mutation ; Pedigree

OBJECTIVETo explore F (13) A gene mutation in a pedigree with hereditary coagulation factor XIII (FXIII) deficiency.

METHODSThe FXIII deficiency was diagnosed by clot solubility test and other standard laboratory clotting tests. All exons, exon-intron boundary sequences of F(13) A gene were amplified by PCR and the products were sequenced directly. Any mutation identified by direct sequencing was confirmed by reverse sequencing. The mutation identified in the proband was screened in the family members.

RESULTSThe assays of PT, Qiulan, fibrinogen leveling, platelet counts, bleeding time were normal and the clot solubility test was positive in the proband. The homozygous deletion of 33 nucleotides (127067de133) in exon 10 of F(13) A gene which resulted in deletion of 11 amino acids in FXIIII A protein with 720aa residues was identified in the proband. Family studies showed that the mutation was inherited from the parents both of whom carried the heterozygous deletion mutation.

CONCLUSIONThe homozygous 127067de133 mutation of F(13) A gene is responsible for the disorder of the pedigree.

Adolescent ; Factor XIII ; genetics ; Factor XIII Deficiency ; genetics ; Heterozygote ; Homozygote ; Humans ; Male ; Pedigree ; Sequence Deletion

Adult ; Factor XIII ; antagonists & inhibitors ; Factor XIII Deficiency ; complications ; etiology ; Female ; Humans ; Sjogren's Syndrome ; complications

OBJECTIVETo investigate the mechanisms of DelCD11-279 of factor XIII subunit A mRNA in the pathogenesis of hereditary factor XIII deficiency.

METHODSThe recombinant plasmids containing pET-22b(+)/FXIIIA of normal subject and proband's mother and pET-22b(+)/FXIIIA-Del of the proband were constructed and transformed into E. coli BL21. Expressing protein was analyzed by the SDS-PAGE and purified by Ni-NTA resin. Purified proteins were detected by the Western-blot. The activity of purified protein was detected by the incorporation test with EZ-LinkTM5-(Biotinamido) Pentylamine.

RESULTSThe recombinant plasmids containing pET-22b(+)/FXIIIA and pET-22b(+)/FXIIIA-Del which constructed and identified successfully by enzyme digestion and PCR, were transformed into E. coli BL21 and efficiently expressed by IPTG induction. The molecular weights of expressing proteins are 83 200 and 51 900 by the SDS-PAGE. Expressing proteins were purified by Ni-NTA resin, and were proved to be human FXIIIA proteins by Western-blot. Purified protein activity of proband's mother and proband was 95.87% and 0 of the purified FXIIIA protein activity from the normal subject, respectively.

CONCLUSIONDelCD11-279 of FXIIIA mRNA which encoding a 464 amino acids of inactive FXIIIA protein is one of the molecular mechanisms resulting in FXIII deficiency in the patient.

Escherichia coli ; Factor XIII ; Factor XIII Deficiency ; Humans ; Polymerase Chain Reaction ; RNA, Messenger ; Sequence Deletion

Objective: To explore the relationship between plasma coagulation factor XIII (FXIII) and bleeding events. Methods: A total of 55 cases of acute leukemia (AL) at the myelosuppression phase after chemotherapy hospitalized in our hospital from August 2017 to March 2018 were enrolled, with 35 normal controls. The concentration of plasma coagulation factor XIII (FXIII) was detected by ELISA to determine the relationship between the plasma FXIII levels in AL patients at the myelosuppression phase after chemotherapy with bleeding events. Results: The level of FXIII in AL patients at the myelosuppression phase after chemotherapy was significantly lower than that in controls (P<0.001) . The level of FXIII was inversely related with the bleeding severity (the Spearman correlation coefficient -0.761) . Given the diagnosis cut-off point of FXIII concentration as 103.9 μg/L, the sensitivity of diagnosing bleeding in AL patients at the myelosuppression phase after chemotherapy was 0.939, and the specificity 0.909. Conclusion: AL patients at the myelosuppression phase after chemotherapy had low level of plasma FXIII, and patients with lower plasma FXIII associated with higher incidence and severity of bleeding. FXIII level was an independent influencing factor of bleeding in AL patients at the myelosuppression phase after chemotherapy.
Acute Disease ; Blood Coagulation Tests ; Factor XIII ; Factor XIII Deficiency ; Hemorrhage ; Humans ; Leukemia

To investigate the effect of additional factor XIII on the rate of cross-linked fibrin formation in fibrin glue, we prepared concentrated fibrinogen as a source of fibrin glue using thaw -syphon method from fresh frozen plasma, purified human factor XIII from plasma, and performed biochemical analysis of the fibrin glue formed with or without additional factor XIII. It was concluded that additional factor XIII promoted rapid formation of cross-linked fibrin (gamma-gamma dimer and a-polymer) which would be essential to clinically effective fibrin glue.
Factor XIII* ; Fibrin Tissue Adhesive* ; Fibrin* ; Fibrinogen ; Humans ; Plasma

OBJECTIVETo identify the genetic defect of inherited coagulation factor (F) deficiency in a Chinese family and to explore its molecular mechanism.

METHODSThe activity and antigen of plasma F were measured by photometric test and enzyme-linked immunosorbent assay, and rocket-electrophoresis, respectively. All the exons and exon-intron boundaries of the FA subunit gene were amplified by PCR and then DNA sequencing was performed. Restriction endonuclease analysis was used for the PCR products of the family members and 80 healthy donors to exclude gene polymorphism.

RESULTSRapid dissolution of the proband's fibrin clot occurred within 30 minutes, and antigen of his plasma F was significantly decreased, two compound heterozygous missense mutations (a C to T transition at nucleotide 177,246 which caused Arg703Trp, and a A to G transition at nucleotide 177,286 which caused His716Arg) in exon 15 of FA subunit gene were found. The possibility of gene polymorphism was excluded by restriction endonuclease analysing. Each of these two missense mutations was respectively found in his mother and father. Molecular modeling based on 3D crystallographic data predicted that the mutant protein decreased stability and was likely to be rapidly degraded.

CONCLUSIONSThe inherited F deficiency in the Chinese family is caused by two compound heterozygous missense mutations-Arg703Trp and His716Arg in the FA subunit, which to our knowledge, are reported for the first time.

Base Sequence ; Child ; Exons ; Factor XIII ; genetics ; Factor XIII Deficiency ; genetics ; Heterozygote ; Humans ; Male ; Molecular Sequence Data ; Mutation, Missense ; Pedigree

OBJECTIVETo analyze the expressed mRNA of the factor subunit A (FA) in monocyte in a hereditary factor (F) deficiency family.

METHODSThe F A mRNA of the proband and the other family members was analyzed by RT-PCR, semi-quantitative RT-PCR, cloning and sequencing. The three dimensional structure of the protein was predicted by SWISS-MODEL and viewed by RASMIOL.

RESULTS(1) A large in frame deletion from codons 11 to 279, spanning from exon 2 to 7 of F A (DelCD11-279), was identified in the proband at mRNA level and a truncated protein is predicted composed of 464 amino acids. Compared with the normal and the other families, the proband showed lower level of F A mRNA in RT-PCR. (2) SWISS-MODEL analysis showed that the truncated protein lacked the β-sandwich and a part of catalytic core, resulting in loss of the normal catalytic domains.

CONCLUSIONDelCD11-279 of F A mRNA is associated with hereditary F deficiency. The reduced expressing level of F A gene is one of the causes resulting in F deficiency in the patients.

Adolescent ; DNA Mutational Analysis ; Exons ; Factor XIII ; genetics ; Factor XIII Deficiency ; genetics ; Female ; Humans ; Male ; Pedigree ; RNA, Messenger ; genetics ; Sequence Deletion

OBJECTIVETo identify the gene mutation type of an inherited coagulation factor XIII (FXIII) deficiency pedigree.

METHODSPCR and DNA sequencing were used to identify the mutations in the 15 exons and the flank sequence of FXIII gene in the proband. The identified mutations were validated by allele specific PCR, PCR restriction fragment length polymorphism technique or DNA sequencing in the family members and 100 healthy volunteers.

RESULTSArg77Cys and Argl74stop double heterozygous mutations were discovered in the proband. The pedigree analysis showed that Arg77Cys missense mutation inherited from her father, and Arg174stop from her mother. The Arg77Cys missense mutation in exon 3 was not found in her husband and the other 100 healthy volunteers.

CONCLUSIONA novel Arg174stop nonsense mutation was discovered in human FXIII gene. A simple DNA assay based on PCR for detection of this mutation was developed. The congenital FXIII deficiency in the proband might be caused by the coinheritance of the Arg77Cys missense mutation in exon 3 and the Arg174stop nonsense mutation in exon 4.

Adult ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; DNA Mutational Analysis ; Exons ; Factor XIII ; genetics ; Factor XIII Deficiency ; genetics ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Pedigree