• Proceedings of the Korean Society of Radiological Science
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• 1995.10a
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• pp.148-149
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• 1995

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.190-190
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• 2004

Tissue plasminogen activator (tPA) plays important roles in the brain after excitotoxic injury. This study was conducted to produce transgenic pig harboring human tissue plasminogene activator (htPA) gene. Recombinent htPA(rhtPA) genes containing bovine-β-casein promoter (bBC) were prepared for microinjection and testified the expression level of htPA protein from the Chinese hamster ovary (CHO) cell lines before NDA microinjection into the porcine pronuclei. (omitted)

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.522-525
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• 1988

A method to produce tissue type Plasminogen Activator (tPA) from normal human fibroblast is developed by cultivating cells in serum free media containing heparin as an inducer. Optimal dose of this inducer was 30$\mu$g/m$\ell$. The composition of serum free medium was also defined to fit to the industrial scale cultivation. 1.42 ug of tPA per 10$^5$ viable cells per ml was produced. 1.1 gram of tPA can be produced every day from this cell line under normal perfusion chemostat operations assuming that same productivity is maintained when the process is sealed up. This method could reduce pro-duction costs and simplify purification processes by using serum free medium. Tissue type PA produced from this cell line has high ability of dissolving clots, based upon fibrin lysis test showing 50mm$^2$ of clearing zones in agarose gel plate. These results were reproducible and in good agreement with results of ELISA assay. tPA from normal human cells will be safer than that from melanoma and recombinant cells in human clinical trials.

• Animal cells and systems
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• v.10 no.2
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• pp.79-83
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• 2006

Tissue plasminogen activator (tPA) is used to lyse clots and reperfuse brain in ischemic stroke. However, sideeffects of intracerebral hemorrhage (ICH) and edema limit their clinical application. In part, these phenomena has been linked with elevations in matrix metalloproteinase-9 (MMP-9) in neurovascular unit. However little is known about their regulatory signaling pathways in brain cells. Here, I examine the role of MAP kinase pathways in tPA-induced MMP-9 regulation in rat cortical astrocytes. tPA $(1-10\;{\mu}g/ml)$ induced dose-dependent elevations in MMP-9 and MMP-2 in conditioned media. Although tPA increased phosphorylation in two MAP kinases (ERK, JNK), only inhibition of the JNK pathway by the JNK inhibitor SP600126 significantly reduced MMP-9 upregulation. Neither ERK inhibition with U0126 nor p38 inhibition with SB203580 had any significant effects. Taken together, these results suggest that c-jun N-terminal kinase (JNK) plays an essential role for tPA-induced MMP-9 upregulation.

• Journal of Embryo Transfer
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• v.25 no.3
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• pp.171-177
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• 2010

Plasminogen activators (PAs) are serine proteases that convert plasminogen to plasmin. The PA/plasmin system has been associated with a number of physiological processes such as fibrinolysis, ovulation and fertilization. Although correlations have been reported between reactive oxygen species (ROS) and oocyte maturation, the relationship between PA activity and ROS is unknown. The present study was undertaken to determine the effects of cumulus cells on PA activity in matured porcine oocytes under xanthine (X)-xanthine oxidase (XO) system. When oocytes were matured under the X-XO system, the proportion of oocytes remaining GV stage was higher (p<0.05) in oocytes without cumulus cells. The incidence of degenerated oocytes was higher (p<0.05) in the X+XO ($11.1{\pm}6.1$ and $21.6{\pm}3.4%$) than in the control group ($2.9{\pm}1.8$ and $4.0{\pm}1.6%$). The proportion of TUNEL-positive oocytes and activity of caspase-3 were higher (p<0.05) in cumulus-free oocytes and oocytes exposed to ROS. Tissue-type plasminogen activator-plasminogen activator inhibitor (tPA-PAI) and tissue-type plasminogen activator (tPA) activity were detected in oocytes that were separated from cumulus-oocytes complexs (COCs) at 44 h of maturation culture, and only tPA was produced in oocytes that were denuded before the onset of maturation culture. On the other hand, the activities of PA were increased (p<0.05) when oocytes were cultured under the X-XO system. The higher activity of tPA was observed in denuded oocytes (DOs) underwent apoptotic changes by oxidative stress. In COCs, however, tPA-PAI as well as tPA activity was detected and apoptotic changes such as DNA cleavage or caspase-3 activation were not observed. These results suggest that tP A may be relevant to apoptotic cell death in porcine oocytes by oxidative stress.

• Reproductive and Developmental Biology
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• v.29 no.2
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• pp.75-82
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• 2005

This study were examined whether plasminogen activators (PAs) are produced by porcine fresh or frozen-thawed cumulus-oocytes complexes (COCs) and cumulus cell free-oocytes. In fresh or frozen-thawed COCs and oocytes for 0 hour cultured, no activity of PAs was detected. However, at 24 hours of culture urokinase-type plasminogen activator (uPA) was detected in COCs and denuded oocytes. In the frozen-thawed COCs and cumulus cell free-oocytes cultured for 24 hours, no PAs were observed. After COCs were cultured for 48 hours, tissue-type plasminogen activator (tPA) and tPA-PAI were observed in COCs only. In the frozen-thawed COCs and cumulus cell free-oocytes cultured for 48 hours, no PAs were observed. These results suggest that uPA, tPA and tPA-PAI are produced by porcine COCs, but only uPA by oocytes during maturation for 24 hours. Only tPA, and tPA-PAI are produced by COCs cultured for 48 hours, and no PAs are produced by denuded-oocytes cultured for 48 hours. In all of the frozen-thawed groups, no PAs are observed by COCs and denuded-oocytes.

• Journal of Veterinary Clinics
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• v.33 no.3
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• pp.155-159
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• 2016

Four dogs were brought to the Veterinary Medicine Teaching Hospital of Seoul National University (VMTH SNU) with a history of hind limb ataxia, three with pain, one without pain. Three of the four showed weak to absent femoral pulses and cold extremities. Thromboembolism was identified by ultrasonography in the external and/or internal iliac arteries. A thrombolytic agent, recombinant tissue plasminogen activator (rt-PA), was administered (0.5-1 mg/kg, every 60-120 min, 3-5 doses). Two dogs (Cases 2 and 3), which were instantly provided rt-PA treatment, survived 6 and 17 months, respectively, although hematemesis and hematochezia were observed during treatment. In the other two dogs (Cases 1 and 4), rt-PA was administered 4 and 28 days after the appearance of pelvic limb symptoms, which may have limited the benefits of the treatment. When rt-PA treatment is instituted instantly and the side effects are monitored thoroughly during treatment, a good prognosis might be expected in canine aortic thromboembolism. For this reason, we suggest that rt-PA treatment should be initiated immediately if thromboembolism is identified.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1116-1122
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• 2013

Cell line development is the most critical and also the most time-consuming step in the production of recombinant therapeutic proteins. In this regard, a variety of vector and cell engineering strategies have been developed for generating high-producing mammalian cells; however, the cell line engineering approach seems to show various results on different recombinant protein producer cells. In order to improve the secretory capacity of a recombinant tissue plasminogen activator (t-PA)-producing Chinese hamster ovary (CHO) cell line, we developed cell line engineering approaches based on the ceramide transfer protein (CERT) and X-box binding protein 1 (XBP1) genes. For this purpose, CERT S132A, a mutant form of CERT that is resistant to phosphorylation, and XBP1s were overexpressed in a recombinant t-PA-producing CHO cell line. Overexpression of CERT S132A increased the specific productivity of t-PA-producing CHO cells up to 35%. In contrast, the heterologous expression of XBP1s did not affect the t-PA expression rate. Our results suggest that CERT-S132A-based secretion engineering could be an effective strategy for enhancing recombinant t-PA production in CHO cells.

• Korean Journal of Biological Psychiatry
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• v.23 no.4
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• pp.140-147
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• 2016

Objectives To determine the relationship between the Alu insertion/deletion (I/D) polymorphism in the tissue-type plasminogen activator (tPA) gene and the clinical outcome of mirtazapine treatment in Korean major depressive disorder (MDD) patients. Methods We enrolled 422 patients in this study. Symptoms were evaluated using the 21-item Hamilton Depression Rating (HAMD-21) Scale. After 1, 2, 4, and 8 weeks of mirtazapine treatment, the association between the Alu I/D polymorphism in the tPA gene and remission/response outcomes were evaluated. Results The proportion of I/I homozygotes in responders was higher than that in non-responders, whereas the proportion of D/D homozygotes in responders was lower than that in non-responders at 8 weeks of treatment (p = 0.032, OR = 1.57). The percentage decline of HAMD-21 scores in I allele carriers was larger than that of D/D homozygotes at 2 and 8 weeks of treatment (p = 0.035 and 0.007, respectively). I allele carriers were associated with remission at 8 weeks of treatment (p = 0.047, OR = 2.2). Conclusions These results show that treatment response and remission to mirtazapine were associated with the Alu I/D polymorphism of the tPA gene. This suggests the Alu I/D polymorphism may be a potential genetic marker for the prediction of therapeutic response to mirtazapine treatment in patients with MDD.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1299-1305
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• 2011

An important modification of thrombolytic agents is resistance to plasminogen activator inhibitor-1 (PAI-1). In previous studies, a new truncated PAI-1-resistant variant was developed based on deletion of the first three domains in t-PA and the substitution of KHRR 128-131 amino acids with AAAA in the truncated t-PA. The novel variant expressed in a static culture system of Chinese Hamster Ovary (CHO) DG44 cells exhibited a higher resistance to PAI-1 when compared with the full-length commercial drug; Actylase. In the present study, the truncated-mutant protein was expressed in CHO DG44 cells in 50 ml orbital shaking bioreactors. The final yield of the truncated-mutant in the culture was 752 IU/ml, representing a 63% increase compared with the static culture system. Therefore, these results suggest that using the combined features of a transient and stable expression system is feasible for the production of novel recombinant proteins in the quantities needed for preclinical studies.