Adenoviridae ; genetics ; Gene Expression ; Hepatic Stellate Cells ; metabolism ; Humans ; Urokinase-Type Plasminogen Activator ; genetics ; metabolism

The thrombolytic agent DSPAalpha1 is currently undergoing clinical trials for the treatment of acute ischemic stroke and has shown good pharmacodynamic, pharmacokinetic and safety profiles. Here, the DSPAalpha1 gene, optimized for the preferred codons of yeast, was cloned into the Pichia pastoris strains GS115 and KM71. Both expression systems produced functional DSPAalpha1 into the broth medium under shaking flask growth conditions with the yield of about 70 mg/L, and 105 mg/L, respectively. In addition, three glycosylation minus DSPAalpha1 mutants, constructed by site-directed mutagenesis, were also expressed in Pichia pastoris. The mutant proteins were assayed by SDS-PAGE and fibrin degradation activities were evaluated. The secretion levels of all the mutants, especially N362Q and N117Q/N362Q, were so lower compared to the wild-type DSPAalpha1 that only minimal quantities of mutant protein could be recovered by purification from the culture medium. The protein specific activities from mutants (N117Q, N362Q) were less 25% than that of the wild type protein. These results imply that the N-linked carbohydrate chains (at N117 and N362) are vital for the enzymatic activity of rDSPAalpha1 and for its secretion from Pichia pastoris.
Fibrinolytic Agents ; metabolism ; Genetic Vectors ; genetics ; Glycosylation ; Pichia ; genetics ; metabolism ; Plasminogen Activators ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; pharmacology

OBJECTIVETo construct the expression vector of human tissue factor (TF), and investigate the influence of TF/coagulant factor VIIa (FVIIa) complex on the transcriptional expression of urokinase plasminogen activator (u-PA) and u-PA receptor (u-PAR) in human ovarian cancer.

METHODSThe human TF cDNA was obtained from placenta by RT-PCR and then inserted into eukaryotic expression vector pcDNA3 to obtain the TF-pcDNA3 combinant. This combinant was transfected into human ovarian cancer cell line A2780 by lipofectamine. Stably-transfected cells A2780/TF were screened. A2780 and A2780/TF cell lines were stimulated by FVIIa respectively, and the transcriptional levels of u-PA and u-PAR were examined by RT-PCR.

RESULTS(1) The constructed product was identified as TF-pcDNA3 combinant by sequencing. (2) TF was highly expressed not only at transcriptional level in the stable-transfected A2780/TF cell (transfected cell 3.91 +/- 0.28, untransfected cell 0.97 +/- 0.23, P < 0.01), but also on the membrane of the cell surface [transfected cell (48.56 +/- 9.53)%, untransfected cell (2.73 +/- 1.15)%, P < 0.01]. (3) The u-PA and u-PAR mRNA levels in A2780 cell line did not change significantly after stimulated by FVIIa; (4) While stimulated by FVIIa, the u-PAR mRNA levels in A2780/TF cells increased significantly in both dose-dependent and time-dependent manner, while the u-PA mRNA levels did not change significantly; (5) In the A2780/TF cell line the enhanced expression of u-PAR mRNA by FVIIa was significantly inhibited by coincubated with anti-TF antibody.

CONCLUSIONTF/FVIIa complex could up-regulate the transcription of u-PAR in human ovarian cancer cells so as to enhance tumor invasion and metastasis.

Cell Line, Tumor ; Factor VIIa ; genetics ; metabolism ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Ovarian Neoplasms ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Receptors, Urokinase Plasminogen Activator ; genetics ; metabolism ; Thromboplastin ; genetics ; metabolism ; Up-Regulation ; Urokinase-Type Plasminogen Activator ; genetics ; metabolism

OBJECTIVETo investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women.

METHODSThe study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis.

RESULTSThe frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12).

CONCLUSIONThe present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.

Adult ; Female ; Humans ; Infertility ; genetics ; Plasminogen Activator Inhibitor 1 ; genetics ; Polymorphism, Genetic ; Pregnancy ; Uterine Diseases ; genetics ; Women's Health

OBJECTIVETo report a patient with congenital plasminogen activator inhibitor-1 (PAI-1) deficiency and explore its molecular mechanism.

METHODSThe activities of tissue plasminogen activator (tPA), alpha(2) antiplasmin (alpha(2)AP) and PAI-1 were measured by the methods of chromogenic substrate, the antigens of tPA and PAI-1 were measured by ELISA. PAI-1 gene was studied by PCR product sequencing and restriction endonuclease ana-lysing.

RESULTSIn the present patient, the euglobulin clot lysis time was 70 minutes and was corrected to normal range after added 50 ng/ml PAI-1 to his plasma. The activities of t-PA, alpha(2)AP, and factor were normal; the activity and antigen of PAI-1 in plasma were both significantly decreased. Nucleotide sequence analysis revealed that the patient had a heterozygous missense mutation in exon 2, a G to A transition at nucleotide 43. The possibility of gene polymorphism was excluded by restriction endonuclease analysing.

CONCLUSIONSIt is the first patient with congenital PAI-1 deficiency reported in China. The PAI-1 deficiency in the patient may be caused by compound heterozygosity, one of which is the G to A transition at nt43, a new mutation in congenital PAI-1 deficiency.

Adult ; Base Sequence ; Humans ; Male ; Molecular Sequence Data ; Mutation ; Plasminogen Activator Inhibitor 1 ; blood ; deficiency ; genetics

BACKGROUNDRecent studies have proved that brain-derived neurotrophic factor (BDNF) possesses angiogenic activity in vitro and in vivo. However, the proangiogenic mechanism of BDNF has not yet been provided with enough information. To explore the proangiogenic mechanism of BDNF, we investigated the effects of BDNF on extracellular proteolytic enzymes, including matrix metalloproteinases (MMPs) and serine proteases, particularly the urokinase-type plasminogen activator (uPA)-plasmin system in human umbilical vein endothelial cells (HUVECs) model.

METHODSTube formation assay was performed in vitro to evaluate the effects of BDNF on angiogenesis. The HUVECs were treated with various concentrations of BDNF (25 - 400 ng/ml) for different (6 - 48 hours), reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assay MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNA in HUVECs, and the conditioned medium was analyzed for MMP and uPA activity by gelatin zymography and fibrin zymography, respectively. uPA, plasminogen activator inhibitor (PAI)-1, tissue inhibitors of metalloproteinase (TIMP)-1, and TIMP-2 were quantified by western blotting analysis.

RESULTSBDNF elicited robust and elongated angiogeneis in two-dimensional cultures of HUVECs in comparison with control. The stimulation of serum-starved HUVECs with BDNF caused obvious increase in MMP-2 and MMP-9 mRNA expression and induced the pro-MMP-2 and pro-MMP-9 activation without significant differences in proliferation. However, BDNF had no effect on TIMP-1 and TIMP-2 production. BDNF increased uPA and PAI-1 production in a dose-dependent manner. Maximal activation of uPA and PAI-1 expression in HUVECs was induced by 100 ng/ml BDNF, while effects of 200 ng/ml and 400 ng/ml BDNF were slightly reduced in comparison with with those of 100 ng/ml. Protease activity for uPA was also increased by BDNF in a dose-dependent manner. BDNF also stimulated uPA and PAI-1 production beyond that in control cultures in a time-dependent manner from 12 hours to 48 hours after BDNF treatment.

CONCLUSIONSBDNF stimulates MMP and uPA/PAI-1 proteolytic network in HUVECs, which may be important to the acquisition of proangiogenic potential.

Brain-Derived Neurotrophic Factor ; pharmacology ; Cells, Cultured ; Gene Expression Regulation ; drug effects ; Humans ; Matrix Metalloproteinase 2 ; genetics ; Matrix Metalloproteinase 9 ; genetics ; Neovascularization, Physiologic ; drug effects ; Plasminogen Activator Inhibitor 1 ; genetics ; RNA, Messenger ; analysis ; Urokinase-Type Plasminogen Activator ; genetics

Tumor angiogenesis plays a pivotal role in the progress of tumor. Among the various endogenous angiogenic inhibitors discovered, the human plasminogen kringle 5 (K5) has been demonstrated to be a potential inhibitor of the proliferation and migration of vascular endothelial cells in vitro. The replication-incompetent adenovirus (Ad) vector Adeno-X-CMV-K5 (Ad-K5) (where CMV is cytomegalovirus) was constructed and its antiangiogenic effect was tested on vascular endothelial cell and tumor cell. For the construction, the K5 cDNA was fused in-frame with human plasminogen signal sequence and inserted into the eukaryotic expression vector pcDNA3 to form pcDNA3K5. The recombinant plasmid was subcloned into the shuttle plasmid pShuttle under the control of the constitutive CMV immediate-early promoter. The plasmid carrying the cDNA for K5 (pShuttleKS) was then recombined with the Adeno-X viral DNA and transformed into E. coli DH5alpha. The resultant recombinant plasmid pAd-K5 was transfected into human embryonic kidney (HEK) 293 cells with liposome. The adenovirus expressing human plasminogen kringle 5 (Ad-K5) was successfully packaged and propagated in 293 cells, as detected by the cytopathic effect (CPE) on the cells, and the viral titer in the supernatant was 5 x 10(8) pfu/mL by plaque assay. Both human umbilical vein endothelial cell line ECV304 and human breast carcinoma cell line MDA-MB-231 were infected with Ad-K5 and Ad-LacZ, which was used the negative control, and assayed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Compared with uninfected control and Ad-LacZ infected control, Ad-K5 infected group at 80 MOI (multiplicity of infection) significantly inhibited ECV304 proliferation; the difference between uninfected control and Ad-LacZ infected control was not significant. In contrast, there was no significant difference in the proliferation of MDA-MB-231 among all the treatments. In addition, the Ad-K5 at 100 MOI inhibited the differentiation and tube formation of ECV304 on ECMatrix gel. These results suggested that the recombinant replication-defective Adenovirus expressing human plasminogen kringle 5 inhibited the proliferation, differentiation and tube formation of ECV304 and had no effect on the proliferation of MDA-MB-231. Adenovirus mediated human plasminogen kringle 5 gene therapy may be a potential treatment of cancer through angiogenesis inhibition.
Adenoviridae ; genetics ; Cell Line ; Cell Line, Tumor ; Cell Proliferation ; Genetic Vectors ; genetics ; Humans ; Neovascularization, Physiologic ; genetics ; physiology ; Peptide Fragments ; genetics ; physiology ; Plasminogen ; genetics ; physiology ; Polymerase Chain Reaction

To obtain a recombinant human plasminogen (hPLG) with potential anti-platelet aggregation activity, we cloned the cDNA coding Pro544 to Asn791 of hPLG, a kringle-deficit derivative (hPLG-deltaK). The Pro559 in activation loop was then mutated into Asp559 to provide Arg-Gly-Asp (RGD) motif. The constructed pPICZalphaA-RGD-HPLG-deltaK plasmid was expressed in yeast Pichia pastoris GS115, which produced RGD-hPLG-deltaK about 0.160 g/L broth. After affinity chromatography, the purity of the recombinant protein reached above 90%. Western blotting test confirmed that it retained the immunological reaction capability as human PLG. Its urokinase activation rate in 24 hours and its fibrinolytic activity made no deference against native hPLG-deltaK (P=0.630, n=5). Importantly, after activation by urokinase, RGD-hPLG-deltaK showed a significantly higher platelet aggregation inhibition rate (Ri) (21.8% +/- 1.57%) than hPLG-deltaK (3.8% +/- 0.33%) (P=0.000, n=5). These results proved that we constructed an hPLG mutant with anti-platelet aggregation activity, which made a foundation for developing innovative thrombolytic drugs with multifunction.
Humans ; Kringles ; genetics ; Oligopeptides ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Plasminogen ; biosynthesis ; genetics ; Platelet Aggregation Inhibitors ; isolation & purification ; pharmacology ; Point Mutation ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; pharmacology

Vampire bat saliva contains a plasminogen activator that presumably assists these hematophagous animals during feeding. Bat-PA (H), the full-length form of Vampire Bat Salivary Plasminogen Activator (DSPAalpha1), is homologous and similar efficacy to tissue-type plasminogen activator (t-PA). The strict fibrin dependence of activity is a characteristic which could be desirable in the fibrinolytic therapy. It is a unique fibrinolytic enzyme that does not promote neurodegeneration. In this study, according to the reported gene sequence (GenBank Accession No. J05082) of Vampire bat (D. rotundus) plasminogen activator. It was the first time to synthesize the full sequence of DSPAalpha1 in vitro and clone it into the expression vector pPIC9K, the recombinant plasmid was linearized and transformed into Pichia pastoris GS115 strain. Secreted expression of recombinant DSPAalpha1 was attained by methanol induction and its molecular mass is 47 kD. To get recombinant GS115 with high amount of protein, hundreds of His+ transformants had been screened to isolate clones resistant to high levels G418 (2-4 mg/mL), the selected clones mini-expressed in Pichia pastoris, and tested their fibrinolytic activities and expressed protein bands by fibrin plate assay and SDS-PAGE. DSPAalpha1 was determined by optical density after SDS-PAGE, the yield is about 30 mg per liter of fermentation culture. DSPAalpha1 derived often from mammalian cells: Chinese hamster ovary (CHO) cells, Baby hamster kidney (BHK) cells, COS cells, which might be produced at high cost. In Pichia pastoris, it is expected to higher yield and lower cost, thus it might be able to serve as new thrombolytic candidate.
Animals ; Base Sequence ; Chiroptera ; genetics ; Genetic Vectors ; genetics ; Molecular Sequence Data ; Pichia ; genetics ; metabolism ; Plasminogen Activators ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Recombination, Genetic ; Sequence Analysis, DNA

OBJECTIVETo investigate the relationship between a single nucleotide insertion/deletion(4G/5G) polymorphism located in the promoter region of the plasminogen activator inhibitor-1(PAI-1) gene and the pathogenesis of pregnancy-induced hypertension syndrome(PIHs).

METHODSThe 4G/5G polymorphism of PAI-1 gene in 171 PIHs patients (PIHs group) and that in 193 normal pregnant women (control group) were detected by a combination of polymerase chain reaction-restriction fragment length polymorphism.

RESULTS(1)The genotype frequencies of PAI-1 gene in PIHs group were 47.4% for 4G/4G, 41.5% for 4G/5G, and 11.1% for 5G/5G. The 4G/4G genotype and 4G allele frequencies of PAI-1 gene(47.4% and 0.681) for PIHs patients were higher than those (21.2% and 0.495) for normal controls respectively (P<0.001). (2)Both the 4G/4G genotype and the 4G allele of PAI-1 gene occurred more frequently in the severe PIHs group(61.3% and 0.758) than those (35.8% and 0.623) in the mild PIHs group respectively (P<0.001). However, there were no significant differences between those in mild group (35.8% and 0.623) and moderate group(42.8% and 0.625) respectively. (3) The 4G/4G genotype was significantly associated with PIHs (OR=3.34, 95%CI: 2.14-5.22).

CONCLUSIONThese findings suggested that PAI-1 gene polymorphism may be a susceptible factor to the pathogenesis of PIHs and the 4G/4G genotype may be one of the major risk factors for PIHs in pregnant women.

Adult ; Female ; Gene Frequency ; Genotype ; Humans ; Hypertension ; genetics ; Plasminogen Activator Inhibitor 1 ; genetics ; Polymorphism, Genetic ; Pregnancy ; Pregnancy Complications, Cardiovascular