• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.243.2-243
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• 1995

No Abstract, See Full Text

• BMB Reports
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• v.39 no.1
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• pp.55-60
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• 2006

We describe a phage display strategy, based on the differential resistance of proteins to denaturant-induced unfolding, that can be used to select protein variants with improved conformational stability. To test the efficiency of this strategy, wild-type and two stable variants of ${\alpha}_1$-antitrypsin (${\alpha}_1AT$) were fused to the gene III protein of M13 phage. These phages were incubated in unfolding solution containing denaturant (urea or guanidinium chloride), and then subjected to an unfavorable refolding procedure (dialysis at $37^{\circ}C$). Once the ${\alpha}_1AT$ moiety of the fusion protein had unfolded in the unfolding solution, in which the denaturant concentration was higher than the unfolding transition midpoint ($C_m$) of the ${\alpha}_1AT$ variant, around 20% of the phage retained binding affinity to anti-${\alpha}_1AT$ antibody due to a low refolding efficiency. Moreover, this affinity reduced to less than 5% when 10 mg/mL skimmed milk (a misfolding-promoting additive) was included during the unfolding/refolding procedure. In contrast, most binding affinity (>95%) remained if the ${\alpha}_1AT$ variant was stable enough to resist unfolding. Because this selection procedure does not affect the infectivity of M13, the method is expected to be generally applicable to the high-throughput screening of stable protein variants, when activity-based screening is not possible.

• The Korean Journal of Cytopathology
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• v.6 no.2
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• pp.106-115
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• 1995

Reactive humsn mesothelial cells were examined by immunocytochemical stain with intermediate filaments (cytokeratin [CK1, CK7, CK8, CK18, CD19), vimentin, desmin, actin), epithelial membrane antigen, carcinoembryonic antigen (CEA), MHC class II antigen (HLA-DR), LeuM-1 (CD15), $\alpha1-antitrypsin$(ACT), $\alpha1-antichymotrypsin$ (ACHT), CD68(KP-1) and FcyRIII(CD16). The mesothelial cells were isolated from patients with liver cirrhosis and pleural effusion, and short-term cultured in RPMI 1640 media containing 10% heat inactivated fetal calf serum and 1% identical supernatant fluid of the patients' transudates. The results obtained are as follows 1. The cultured-reactive mesothelial cells were positive for the protein of cytoskeleton such as cytokeratin and vimentin, but negative for desmin and actin. The resting mesothelial cells showed positive reactions for cylokeratin, but negative for vimentin, desmin and actin. 2. The primary antibodies to the cytokeratin were strongly reactive for CK1, CK8 and CK18 but negative for CK7 and CK19 in both reactive and resting mesothelial cells. 3. Resting mesothelial cells showed negative reactions for CEA, but strong positive reactions in cultured-reactive mesothelial cells. 4. The markers for the monocytes/histiocytes(CD11b, CD14, CD16, CD68, Iysozyme and $\alpha1-antitrypsin$ and $\alpha1-antichymotrypsin$) were nonreactive in resting mesothelial cells, but lysozyme and $\alpha1-antitrypsin$ were weakly reactive in reactive and proliferative mesothelial cells. 5. MHC Class II molecule(HLA-DR antigen) was negative in both resting and reactive mesothelial cells. These results suggest that the short-term cultured, reactive mesothelial cells show a newly aberrant expression of the vimentin and calcine-embryonic antigen. The reason of the aberrant expression of the intermediate filament and oncofetal antigen in reactive and proliferative mesothelial cells should be further evaluated.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10187-10192
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• 2015

Cytochrome P450 (CYP) enzymes are a large family of constitutive and inducible mono-oxygenase enzymes that play a central role in the oxidative metabolism of both xenobiotic and endogenous compounds. Several CYPs are involved in metabolism of oxysterols, which are cholesterol oxidation products whose expression may be dysregulated in inflammation-related diseases including cancer. This study focused on CYP39A1, which can metabolize 24-hydroxycholesterol (24-OH) that plays important roles in the inflammatory response and oxidative stress. We aimed to investigate the expression status of CYP39A1 and its transcription factor (RUNX2) in relation to clinical significance in cholangiocarcinoma (CCAs) and to determine whether 24-OH could induce oxidative stress in CCA cell lines. Immunohistochemistry showed that 70% and 30% of CCA patients had low and high expression of CYP39A1, respectively. Low expression of CYP39A1 demonstrated a significant correlation with metastasis. Our results also revealed that the expression of RUNX2 had a positive correlation with CYP39A1. Low expression of both CYP39A1 (70%) and RUNX2 (37%) was significantly related with poor prognosis of CCA patients. Interestingly, oxidized alpha-1 antitrypsin (ox-A1AT), an oxidative stress marker, was significantly increased in CCA tissues in which CYP39A1 and RUNX2 were down regulated. Additionally, immunocytochemistry showed that 24-OH could induce ox-A1AT in CCA cell lines. In conclusion, our study revealed putative roles of the CYP39A1 enzyme in prognostic determination of CCAs.

• Korean Journal of Microbiology
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• v.30 no.2
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• pp.108-112
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• 1992

To investigate the expression and the secretion of heterologous proteins in yeast, we constructed an yeast secretion vector and produced a human secretory protein, .alpha.-1-antitrypsin (.alpha.-1-AT), from yeast cells. The secretion vector pGAT8 was constructed by inserting the signal sequence of yeast acid phosphatase gene (PH05) into the .alpha.1-AT expression vector pGAT6 which contained .alpha.-1-AT cDNA fused to GAL10-CYC1 promotor. The .alpha.-1-AT was produced efficiently in the yeast cells transformed with plasmid pGAT8, which was onfirmed both by the .alpha.-1-AT activity assay and by the immunoblot method using .alpha.-1-AT antibody. We also showed the secretion of .alpha.-1-AT into the culture media and into the periplasmic space by immunoblot.

• Korean Journal of Veterinary Research
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• v.59 no.1
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• pp.9-15
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• 2019

In canine acute pancreatitis (AP), inappropriate release and activation of zymogen proteases within the pancreas results in the consumption of serum antiproteases. The aim of this study was to examine whether the serum concentrations of ${\alpha}_2$-macroglobulin (A2MG), ${\alpha}_1$-antitrypsin (A1AT), and C-reactive protein (CRP) differ between dogs with AP and healthy dogs. Twenty healthy dogs and 20 dogs with AP were included in this study. Concentrations of A2MG, A1AT, and CRP were measured in the sera of healthy dogs and dogs diagnosed with AP. Serum A2MG and A1AT concentrations were significantly lower in dogs with AP than in healthy dogs, whereas the serum CRP concentration was significantly higher. In addition, the concentrations of A2MG and A1AT were significantly higher in AP survivors than in AP non-survivors, while the CRP concentration was significantly lower. However, in both AP survivors and non-survivors, the CRP concentrations showed a negative correlation with A2MG concentrations but not with A1AT. These findings indicate that serum antiproteases and CRP concentrations might be associated with the mortality rate of AP in dogs.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.80-80
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• 1995

No Abstract, See Full Text

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.30-30
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• 2002

The native forms of common globular proteins are in their most stable state but the native forms of plasma serpins (serine protease inhibitors) show high-energy state interactions. The high-energy state strain of a ${\alpha}$$_1$-antitrypsin, a prototype serpin, is distributed throughout the whole molecule, but the strain that regulates the function directly appears to be localized in the region where the reactive site loop is inserted during complex formation with a target protease.(omitted)

• Clinical and Experimental Pediatrics
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• v.46 no.9
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• pp.921-925
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• 2003

Intestinal lymphangiectasia, one of the protein-losing gastroenteropathies, is an uncommon disease characterized by dilated intestinal lymphatics, enteric protein loss, edema, hypoalbuminemia, and lympocytopenia. Small bowel biopsy and CT have been used to confirm the diagnosis of intestinal lymphangiectasia. Small bowel biopsy shows collections of abnormal dilated lacteals in submucosa with distortion of villi and CT findings have been described as diffuse nodular thickening of the small bowel and as linear hypodense streaking densities in the small bowel caused by dilated lymphatic channels. Demonstration of increased enteric protein loss using $^{51}Cr-$, $^{131}I-$ or $^{99m}Tc-labeled$ albumin, timed measurement of fecal excretion of radioactivity or by measuring fecal clearance of alpha 1-antitrypsin can also help the diagnosis. We experienced a rare case of intestinal lymphangiectasia in an eight year old boy who presented with facial edema, abdominal distension and intermittent diarrhea. We report a patient with intestinal lymphangiectasia, in whom abdominal CT, $^{99m}Tc-labeled$ albumin scintitigraphy, and stool alpha 1-antitrypsin measurement played key roles in determining the diagnosis. A brief review of literature was made.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.4-4
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• 1996

$\alpha$$_1$-arantitrypsin, a member of the serpin (serine protease inhibitor) family, undergoes a large structural rearrangement upon the cleavage and insertion of the reactive site loop. This conformational change is driven by the metastability of the native serpin structures and has an important role in the regulation of the inhibitory-serpin function. (omitted)