OBJECTIVE: To construct a mouse model of Glanzmann's thrombasthenia (GT) with ITGA2B c.2659 C>T (p.Q887X) nonsense mutation by CRISPR/Cas9 technology, and then further explore the expression and function of glycoprotein αIIbβ3 on the surface of platelet membrane. METHODS: The donor oligonucleotide and gRNA vector were designed and synthesized according to the ITGA2B gene sequence. The gRNA and Cas9 mRNA were injected into fertilized eggs with donor oligonucleotide and then sent back to the oviduct of surrogate mouse. Positive F0 mice were confirmed by PCR genotyping and sequence analysis after birth. The F1 generation of heterozygous GT mice were obtained by PCR and sequencing from F0 bred with WT mice, and then homozygous GT mice and WT mice were obtained by mating with each other. The phenotype of the model was then further verified by detecting tail hemorrhage time, saphenous vein bleeding time, platelet aggregation, expression and function of αIIbβ3 on the surface of platelet. RESULTS: The bleeding time of GT mice was significantly longer than that of WT mice (P<0.01). Induced by collagen, thrombin, and adenosine diphosphate (ADP), platelet aggregation in GT mice was significantly inhibited (P<0.01, P<0.01, P<0.05). Flow cytometry analysis showed that the expression of αIIbβ3 on the platelet surface of GT mice decreased significantly compared with WT mice (P<0.01), and binding amounts of activated platelets to fibrinogen were significantly reduced after thrombin stimulation (P<0.01). The spreading area of platelet on fibrinogen in GT mice was significantly smaller than that in WT mice (P<0.05). CONCLUSION A GT mouse model with ITGA2B c.2659 C>T (p.Q887X) nonsense mutation has been established successfully by CRISPR/Cas9 technology. The aggregation function of platelet in this model is defective, which is consistent with GT performance.
Animals ; CRISPR-Cas Systems ; Codon, Nonsense ; Disease Models, Animal ; Fibrinogen/genetics* ; Humans ; Integrin alpha2/genetics* ; Mice ; Oligonucleotides ; Platelet Glycoprotein GPIIb-IIIa Complex/genetics* ; RNA, Guide ; Thrombasthenia/genetics* ; Thrombin/genetics*

OBJECTIVE: To develop methods of extraction and purification of Cterminal NUDT9 homology domain of human transient receptor potential melastatin 2 (TRPM2) channel. METHODS: After sonication and centrifuge of strain Rosetta (DE3) which was induced by isopropylthio-β-D-galactoside, GST-NUDT9-H was collected after the binding of supernatant with GST beads and eluted with reduced glutathione. Then the elution buffer containing fusion protein was purified by size exclusion chromatography after concentration and centrifuge. Finally, with the cleavage of thrombin and binding with the GST beads, NUDT9-H with high purity in supernatant was collected. RESULTS: The GST-NUDT9-H fusion protein was stabilized with lysis buffer containing 0.5% n-dodecyl -β-d-maltoside (DDM), and wash buffer containing 0.025% DDM in size-exclusion chromatography system, and finally the NUDT9-H with high purity was obtained after cleaved by thrombin (1 U/2 mg fusion protein) for 24 h. CONCLUSIONS Due to the poor stability of NUDT9-H, it is necessary to add DDM in extraction and purification buffer to stabilize the conformation of NUDT9-H, so as to increase its yields and purity.
Escherichia coli ; genetics ; Glucosides ; chemistry ; Humans ; Protein Domains ; Protein Stability ; Pyrophosphatases ; chemistry ; genetics ; isolation & purification ; Recombinant Fusion Proteins ; chemistry ; isolation & purification ; TRPM Cation Channels ; chemistry ; isolation & purification ; Thrombin ; metabolism

OBJECTIVETo explore the molecular pathogenesis and clinical phenotypes in 10 probands with inherited fibrinogen (Fg) deficiency.

METHODSThe diagnosis of hereditary Fg deficiency was validated by prothrombin time (PT), thrombin time (TT), Fg activity (Fg:C) and Fg antigen (Fg:Ag) in plasma. All of the exons and their flanking sequences of the Fg gene were analyzed by direct sequencing. Detected mutations were confirmed by reverse sequencing.

RESULTSThe ranges of Fg:C and Fg:Ag in the 10 probands were 0.52-0.91 g/L and 0.62-2.98 g/L, respectively. Five of the probands had type I disorders, and 5 had type II disorders. Seven point mutations were identified, among which 6 have located in the D region. γThr277Arg, γAsp316His, γTrp208Leu and Lys232Thr were novel mutations, and αArg19Ser was first reported in Chinese. Four probands had the same mutation site (γArg275). As to the clinical manifestation, probands with type I disorders were asymptomatic or with mild or medium symptoms, while those belonged to type II disorders had moderate or serious symptoms. Two probands have carried an Arg275Cys mutation but had different clinical manifestations.

CONCLUSIONMutations of the Fg gene seem to aggregate to the D region of FGG in our region, and Arg275 is a common mutation. However, no correlation has been found between the mutation site and clinical manifestations.

Adolescent ; Adult ; Afibrinogenemia ; blood ; classification ; genetics ; Base Sequence ; Child ; DNA Mutational Analysis ; methods ; Exons ; genetics ; Family Health ; Female ; Fibrinogen ; genetics ; metabolism ; Genotype ; Humans ; Male ; Middle Aged ; Mutation, Missense ; Partial Thromboplastin Time ; Phenotype ; Point Mutation ; Polymerase Chain Reaction ; Prothrombin Time ; Thrombin Time ; Young Adult

OBJECTIVETo analyze the phenotype, genotype and function in four Chinese pedigrees with inherited dysfibrinogenemia.

METHODSRouting tests including activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), reptilase time (RT), the activities of antithrombin (AT), protein C (PC) and protein S (PS) were detected in four pedigrees. The activity and antigen of plasma fibrinogen were analyzed by Clauss and immunoturbidimetry methods, respectively. The molecular weight of fibrinogen of four probands was assessed by Western blot. The function of abnormal fibrinogen was evaluated by fibrinogen clottability, fibrinogen dynamic polymerization and fibrinolysis velocity, respectively. The sequences of all the exons and exon-intron boundaries of the three fibrinogen genes were amplified by PCR and analyzed by direct sequencing.

RESULTSFour probands had prolonged TT and RT, reduced plasma fibrinogen activity levels and normal antigen levels. The assays of Western blot showed no abnormal molecular weight of fibrinogen. Function tests revealed reduced fibrinogen clottability, delayed and decreased fibrinogen dynamic polymerization and reduced fibrinolysis velocity. Aα chain Arg16His and Arg16Cys mutations were identified in the four probands, respectively.

CONCLUSIONThe four probands with dysfibrinogenemia were caused by the mutations of Aα chain Arg16His or Arg16Cys. Mutation of the fibrinogen induced dysfunction of plasma fibrinogen.

Adult ; Afibrinogenemia ; blood ; genetics ; Blood Coagulation Tests ; Female ; Fibrinogen ; genetics ; Fibrinogens, Abnormal ; genetics ; Genotype ; Humans ; Male ; Middle Aged ; Pedigree ; Phenotype ; Thrombin Time

Animals ; Cardiovascular Diseases ; etiology ; metabolism ; Humans ; Inflammation ; metabolism ; Periodontitis ; complications ; metabolism ; microbiology ; Platelet Aggregation ; physiology ; Porphyromonas gingivalis ; pathogenicity ; RNA, Messenger ; metabolism ; Receptor, PAR-1 ; metabolism ; Receptor, PAR-2 ; genetics ; metabolism ; Receptors, Proteinase-Activated ; metabolism ; Receptors, Thrombin ; metabolism

BACKGROUNDIntracerebral hemorrhage (ICH) can cause brain damage through a number of pathways. The purpose of the study was to explore the effect of thrombin, protease nexin-1 (PN-1) and protease activated receptor-1 (PAR-1) in rat and human cerebellum after ICH.

METHODSA model of ICH was produced in adult Sprague-Dawley rats by direct injection of autologous blood (50 microl) into caudate nucleus. Patients with injured hemorrhage were also enrolled in this study. Different expressions of thrombin, PAR-1, PN-1 were detected in rat and human cerebellum by immunohistochemistry and in situ hybridization.

RESULTSIn rat cerebellum, thrombin protein significantly increased at 6 hours and reached the maximum 2 days after ICH. The expression of PAR-1 protein reached the maximum at 24 - 48 hours, and then began to decrease. The expression of PN-1 protein reached the maximum at 3 hours, decreased somewhat after that and increased a little at 5 days after ICH. While in human cerebellum, the changing tendency of thrombin, PAR-1 and PN-1 was almost conform to the rat.

CONCLUSIONIn cerebellum, thrombin can activate PAR-1 expression after ICH, and PN-1 appears quickly after ICH in order to control the deleterious effect of thrombin.

Adult ; Aged ; Aged, 80 and over ; Animals ; Cerebellum ; metabolism ; Cerebral Hemorrhage ; metabolism ; Female ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Male ; Middle Aged ; Rats ; Rats, Sprague-Dawley ; Receptor, PAR-1 ; genetics ; metabolism ; Serpin E2 ; genetics ; metabolism ; Thrombin ; genetics ; metabolism

OBJECTIVESTo investigate molecular mechanisms of PAR-1 regulation on intracellular Ca²(+) mobilization in lung giant cell carcinoma cells in vitro and its involvement in tumor metastasis.

METHODSFree intracellular Ca²(+) ([Ca²(+)]i) was measured in lung giant cell carcinoma PLA801C and PLA801D cells by confocal microscopy. Sense and anti-sense PAR-1 expression vectors were transfected into PLA801C (C+)and PLA801D(D-) cells, respectively. The effects of PAR-1 expression were investigated by thrombin and TRAP-induced mobilization of [Ca²(+)]i in the C+ and D-cells.

RESULTSThere were significant differences of the mean values of [Ca²(+)]i between PLA801D (59.55) and PLA801C cells (35.46, P < 0.01). The mean [Ca²(+)]i of C+ cells (45.77) was significantly higher than that of its control CV cells (35.46, P < 0.05), and the mean [Ca²(+)]i of D-cells (48.42) was significantly lower than that of its control DV cells (59.55, P < 0.05). The peaks of [Ca²(+)]i of C+ and CV cells were 48.19 ± 9.84 and 45.64 ± 9.87 (P < 0.05) respectively at 80 s and 100 s after thrombin treatment, but were 111.31 ± 25.00 and 52.93 ± 11.21 (P < 0.05) respectively at 60 s after TRAP treatment. The peaks of [Ca²(+)]i of D- and DV cells were 40.71 ± 5.89 and 61.07 ± 21.36 (P < 0.05) respectively at 60 s after thrombin treatment, but were 84.98 ± 11.23 and 102.58 ± 21.48 (P < 0.05) respectively at 40 s after TRAP treatment.

CONCLUSIONSThe high metastatic potential of PLA801D and PLA801C may be related to [Ca²(+)]i of the tumor cells. PAR-1 may play an important role in the metastasis of lung giant cell carcinoma cells by up-regulating the intracellular Ca²(+).

Calcium ; metabolism ; Calcium Signaling ; drug effects ; Carcinoma, Giant Cell ; metabolism ; pathology ; Cell Line, Tumor ; DNA, Antisense ; genetics ; Humans ; Lung Neoplasms ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Receptor, PAR-1 ; genetics ; metabolism ; physiology ; Receptors, Thrombin ; metabolism ; Thrombin ; pharmacology ; Transfection ; Up-Regulation

Thrombin-like enzymes (TLEs) are studied widely because of their therapeutic potential in myocardial infarction and thrombotic diseases. We synthesized the DNA fragment encoding thrombin-like enzyme calobin from Agkistrodon caliginosus (Korean Viper) venom by fusion PCR and expressed it in Pichia pastoris. After induction by 0.5% methanol for 48 h, the expression level of recombinant calobin reached 3.5 g/L in medium. The recombinant calobin was purified by Q-Sepharose Fast Flow ion-exchange chromatography and Sephacryl-S-100 gel filtration chromatography. Purified sample had a molecular weight of 32 kD shown in SDS-PAGE. It hydrolyzed fibrinogen and formed a light white hydrolysis circle in fibrinogen plate. SDS-PAGE analysis showed that recombinant calobin cleaved Aalpha-chain of fibrinogen specifically, and produced an appropriately 40 kD new band. However, we failed to find its fibrin-clot formation activity.
Agkistrodon ; Animals ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Serine Endopeptidases ; biosynthesis ; genetics ; Thrombin ; biosynthesis ; genetics ; Viper Venoms ; enzymology

OBJECTIVETo observe the effects of tetramethylpyrazine (TMP) on tissue factor (TF) expression induced by thrombin in human umbilical vein endothelium derived cell line ECV304.

METHODSThe changes in the total cellular procoagulant activity (PCA) of ECV304 cells exposed to thrombin were observed with one-stage clotting assay. TF mRNA expression in the exposed cells was examined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSECV304 cells stimulated with increasing concentrations of thrombin (1.25-20 U/ml) showed a gradual increase of PCA (r=0.9602, P<0.01). The application of FVII-deficient plasma and the monoclonal antibody of TF confirmed that the PCA of the cells mediated by TF activity. TMP at 125-1000 microg/ml alone did not affect TF expression in ECV304 cells (P>0.20), TMP administered 30 min prior to thrombin exposure showed a significant concentration-dependent inhibitory effect on the increments of PCA (r=-0.9644, P<0.01) and TF mRNA expression (r=-0.9576, P<0.05) in ECV304 cells, and 1000 microg/ml TMP produced the strongest effect. In ECV304 cells stimulated with thrombin for 4, 6, 8, 10 and 12 h, TMP administration significantly inhibited the thrombin-induced PCA, and the effect was especially obvious at 8 h following thrombin exposure (P<0.05).

CONCLUSIONThrombin induces TF expression in vascular endothelial cells, and this effect can be inhibited by TMP at the mRNA level.

Animals ; Cell Line ; Dose-Response Relationship, Drug ; Endothelial Cells ; cytology ; drug effects ; metabolism ; Gene Expression Regulation ; drug effects ; Humans ; Pyrazines ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Thrombin ; pharmacology ; Thromboplastin ; genetics ; metabolism ; Time Factors

OBJECTIVETo observe the effect of Xiaoyu Zhixue Tablet (XYZXT) on expression of platelet membrane glycoproteins (GP) Ib/IX/V complex and its component GP Ibalpha in patients with hemorrhagic thrombopathy, so as to explore its possible mechanism.

METHODSNinety-eight patients with hemorrhagic thrombopathy were randomly assigned to two groups, the TCM group (68 cases) treated with XYZXT and the Western medicine group (30 cases) treated with adrenosin, vitamins C, K and P, for 6 months totally. The hemostatic effect and the platelet aggregation recovery rate in the two groups were observed. And expressions of GPIb/IX/V complex and GP Ibalpha were analyzed by flow cytometry in both groups before and after treatment as well as in 34 healthy persons for control.

RESULTSThe hemostatic effective rate was 89.7% in the TCM group and 46.7% in the Western medicine group (u= 5.68, P < 0.01); the platelet aggregation recovery rate in the two groups was 67.6% and 3.3% respectively (chi2 = 34. 49, P < 0.01). The fluorescence intensity of GPIb/IX/V complex and GPIbalpha were lower in both groups before treatment than those of the healthy control (P < 0.05), but after treatment the two markers elevated in the TCM group, approaching the control (P > 0.05), and significantly higher than those in the Western medicine group (P < 0.05).

CONCLUSIONThe partial mechanism of XYZXT in treating hemorrhagic thrombopathy might be its regulation on the expression of thrombin receptor at the receptor protein level.

Adolescent ; Adult ; Aged ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Gene Expression ; drug effects ; Hemorrhage ; drug therapy ; genetics ; metabolism ; Humans ; Male ; Middle Aged ; Receptors, Thrombin ; genetics ; metabolism ; Tablets ; Young Adult