• The Zoological Society Korea : Newsletter
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• v.18 no.2
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• pp.33-37
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• 2001

Intercellular adhesion molecule-1 (ICAM-1)은 T 세포의 활성이나 면역세포가 염증작용이 일어나고 있는 곳으로 옮겨갈 때 중요한 역할을 수행하는 당단백질 (glycoprotein)으로서 2-integrin 계열의 분자인 leukocyte function associated antigen-1(LFA-1)이나 Mac-1의 수용체이며 세포의 막에 homodimer인 상태로 발현되어진다. ICAM-1은 5개의 세포외 domain과 transmembrane domain(TM) 및 짧은 cytoplasmic domain을 갖고 있으며, dimerization motif는 domain 5 또는 TM인 것으로 알려져 있다. 최근의 crystal 구조분석 결과에 의하면 domain 1에도 dimerization motif가 있는 것으로 추정되어지지만 정확한 실험적인 뒷받침이 되어져 있지 않다. 본 연구에서는domain 1에 dimer를 형성할 수 있는 motif가 존재하는 지에 대한 실험적인 증명과 함께 ICAM-1이 세포의 막에서 어떠한 구조를 갖고 있는지에 대한 최근의 연구성과를 보고하고자 한다.

• Molecules and Cells
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• v.25 no.3
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• pp.452-456
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• 2008

The interactions between monocytes and extracellular matrix proteins have been implicated in atherosclerosis pathophysiology. In the present study we evaluated monocyte attachment and migration through oxidized and non-oxidized collagen IV. Monocyte attachment was tested on microwells coated with either native or oxidized collagen IV. Monocyte migration through collagen IV was examined on transwells. Monocytes derived from patients with diabetes mellitus showed an increased ability to attach and migrate through collagen IV as compared to those derived from healthy volunteers. Moreover, control monocytes attached to oxidized collagen at a higher degree, while they migrated through oxidized collagen at a lower degree, as compared to the native protein. Our results also showed the involvement of the alpha2 integrin subunit in the above phenomena suggesting a modified interaction between monocytes and collagen IV in diabetes mellitus.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.131-135
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• 2000

Human polymorphonuclear neutrophils undergo diaphoresis after a selectin-mediated rolling on the endothelial cells of the blood vessel wall. Extravasation is believed to be an integrin-mediated process. Galectin-1 is a small dimeric beta-galactoside-binding protein synthesized by the endotherial cells and present in the perivascular connective tissue. In this study we suggest the possible role of galectin-1 in extravasation of the activated neutrophils. MAL lectin binding study showed, that f-MetLeuPhe-activated neutrophils decrease surface sialylation and increase galectin-1 binding via exposure of new galectin-1 binding sites. Desialylated HL-60 cells also show the same decrease in MAL binding and increase in galectin-1 binding, an increase which was not observed in the presence of lactose. Galectin-1 blotting analysis detected two possible major ligands (approximately 120 and 160 kDa) of galectin-1 from the desialylated HL-60 cell lysates.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.99.2-99.2
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• 2003

One of the major limitations in using adenoviral vector for gene therapy is inefficient infection of host cells. The presence of coxsackievirus and adenovirus receptor (CAR) and ${\alpha}$-integrin on cell surfaces is required for efficient adenovirus infection. In this study, we investigated the effect of trichostatin A, a histone deacetylase inhibitor, on transfection efficiency after transduction of adenovirus mediated p16$\^$INK4a/ gene transfer. In our previous study, p16$\^$INK4a/ tumor suppressor gene transfer in the non-small cell lung cancer cells (A549 cells) by transduction of recombinant adenovirus (Ad5CMV-p16) resulted in significant inhibition of cancer cell proliferation. (omitted)

• Korean journal of applied entomology
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• v.55 no.2
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• pp.81-89
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• 2016

Double-stranded RNA (dsRNA) has been applied to control insect pests by its suppressive activity against specific target genes. Integrin is a heterodimer (${\alpha}$ and ${\beta}$) transmembrane protein and plays a critical role in cell-to-cell or cell-to-extracellular matrix interactions in eukaryotes. Suppression of ${\beta}$ subunit integrin gene expression by its specific dsRNA (= dsINT) induces significant mortality against target insects. Furthermore, a recombinant bacterium expressing dsINT is potent to kill target insects. However, it is necessary to develop a formulation technique of the dsRNA-expressing bacteria to apply the bacterial insecticide against field populations. This study formulated the recombinant bacteria by freeze-drying and tested its control efficacy against target insects. The formulation maintained significant insecticidal activity against last instar larvae of Spodoptera exigua. While a commercial Bacillus thuringiensis (Bt) insecticide exhibited only about 60% insecticidal activity against S. exigua last instar, an addition of the dsINT-expressing bacterial formulation significantly enhanced the Bt insecticidal activity. The dsINT-expressing bacterial formulation exhibited relative selectivity to target insects depending on sequence similarity. These results indicate that a freeze-dried form of dsRNA-expressing bacteria keeps its insecticidal activity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.4
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• pp.431-436
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• 2013

Bone homeostasis is maintained by co-ordination of bone-resorbing osteoclasts and bone-forming osteoblasts. Imbalance between osteoclasts and osteoblasts leads to many bone diseases such as osteoporosis, rheumatoid arthritis. Taxillus chinensis is a herb that has been widely used to improve bone health. However, the effect and mechanism of Taxillus chinensis extract on osteoclast differentiation and bone resportion has been unknown. Thus, We investigated the effect of Taxillus chinensis on expression of receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation and bone resorption. Also, the action of Taxillus chinensis on mechanisms relating to osteoclast differentiation was studied. In this results, we identified that Taxillus chinensis significantly inhibited RANKL-induced osteoclast differentiation and bone resportion. Moreover, Taxillus chinensis was suppressed the activation of NF-${\kappa}B$ in bone marrow macrophage treated RANKL and M-CSF. Taxillus chinensis was down-regulated the mRNA expression of c-Fos, nuclear factor of activated T-cells (NFAT)c1, osteoclast-associated receptor (OSCAR), tartrate-resistant acid phosphatase (TRAP). The cell adhesion-related molecules such as integrin ${\alpha}v$ and integrin ${\beta}3$, and the filamentous actin (F-actin) rings of mature osteoclasts-related molecules such as dendritic cell-specific transmembrane preotein (DC-STAMP) and cathepsin K are also suppressed. Taken together, these results indicated that Taxillus chinensis will be a good candidate to treat osteoclast-mediated bone diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.201-208
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• 2013

Objective: To investigate changes in the invasive capacity of gastric cancer cells in vitro after expression inhibition of T lymphoma invasion and metastasis inducing factor 1 (Tiam 1) and underlying mechanisms. Methods: Using adhesion selection, two subpopulations with high ($M_H$) or low ($M_L$) invasive capacity were separated from the human gastric cancer cell line MKN-45 ($M_0$). Tiam 1 antisense oligodeoxynucleotide (ASODN) was transfected into $M_H$ cells with liposomes, and expression of Tiam 1 mRNA and protein was determined by RT-PCR and quantitative cellular-ELISA. Changes in the cytoskeleton, invasive capacity in vitro and expression of ras-related $C_3$ botulinum toxin substrate 1 (Rac 1), integrin ${\beta}1$ and matrix metalloproteinase 2 (MMP 2) between Tiam 1 ASODN transfected $M_H$ cells and non-transfected cells were observed by HE staining, cytoskeletal protein staining, scanning electron microscopy, Boyden chamber tests and cyto-immunohistochemistry. Results: A positive correlation existed between the expression level of Tiam l mRNA or protein and the invasion capacity of gastric cancer cells. After ASODN treatment ($0.43{\mu}M$ for 48 h), Tiam 1 mRNA transcription and protein expression in $M_H$ cells were decreased by 80% and 24% respectively (P < 0.05), compared with untreated controls, while invasive capacity in vitro was suppressed by 60% (P < 0.05). Morphologic and ultrastructural observation also showed that ASODN-treated $M_H$ cells exhibited smooth surfaces with obviously reduced filopodia and microspikes, which resembled $M_0$ and $M_L$ cells. Additionally, cytoskeletal distribution dramatically altered from disorder to regularity with reduced long filament-like structure, projections, pseudopodia on cell surface, and with decreased acitn-bodies in cytoplasm. After Tiam 1 ASODN treatment, the expression of Rac 1 and Integrin ${\beta}1$ in $M_H$ cells was not affected (P > 0.05), but that of MMP 2 in $M_H$ cells was significantly inhibited compared with untreated cells (P < 0.05). Conclusion: Over-expression of Tiam-1 contributes to the invasive phenotype of gastric cancer cells. Inhibition of Tiam 1 expression could impair the invasive capacity of gastric cancer cells through modulating reconstruction of the cytoskeleton and regulating expression of MMP 2.

• Development and Reproduction
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• v.15 no.1
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• pp.41-52
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• 2011

In the present study, embryoid bodies (EBs) obtained from induced pluripotent stem cells (iPSCs) were induced to differentiate into germ lineage cells by treatment with bone morphogenetic protein 4 (BMP4) and retinoic acid (RA). The results were compared to the results for embryonic stem cells (ESCs) and multipotent spermatogonial stem cells (mSSCs) and quantified using immunocytochemical analysis of germ cell-specific markers (integrin-${\alpha}6$, GFR-${\alpha}1$, CD90/Thy1), fluorescence activating cell sorting (FACS), and real time-RT-PCR. We show that the highest levels of germ cell marker-expressing cells were obtained from groups treated with 10 ng/$m{\ell}$ BMP4 or 0.01 ${\mu}M$ RA. In the BMP4-treated group, GFR-${\alpha}1$ and CD90/Thy-1 were highly expressed in the EBs of iPSCs and ESCs compared to EBs of mSSCs. The expression of Nanog was much lower in iPSCs compared to ESCs and mSSCs. In the RA treated group, the level of GFR-${\alpha}1$ and CD90/Thy-1 expression in the EBs of mSSCs Induced pluripotent stem cells, Mouse embryonic stem cells, Multipotent spermatogonial stem cells, Germ cell lineage, Differentiation potential. was much higher than the levels found in the EBs of iPSCs and similar to the levels found in the EBs of ESCs. FACS analysis using integrin-${\alpha}6$, GFR-${\alpha}1$, CD90/Thy1 and immunocytochemistry using GFR-${\alpha}1$ antibody showed similar gene expression results. Therefore our results show that iPSC has the potential to differentiate into germ cells and suggest that a protocol optimizing germ cell induction from iPSC should be developed because of their potential usefulness in clinical applications requiring patient-specific cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.29-34
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• 2014

Bone homeostasis is maintained by balance between bone resorbing-osteoclasts and bone forming-osteoblasts. Excessive osteoclastic bone resorption plays a critical role in bone destruction in pathological bone diseases such as osteoporosis, rheumatoid arthritis, and periodontal disease. Many compounds derived from natural products have pharmacological applications and have therapeutic value for treating or preventing several bone diseases characterized by excessive bone resorption. To discover new compounds that can act as anti-resorptive agents, we screened for natural compounds that regulate osteclast differentiation, and found that water extract of Ziziphus Jujuba Mill (WEZJ) has inhibitory effects on osteoclast differentiation. In this study, WEZJ clearly inhibits the osteoclast differentiation in the presence of receptor activator of nuclear factor kB (RANKL), macrophage colony-stimulating factor (M-CSF) without cytoxicity by blocking activation of nuclear factor of activated T cells (NFAT)c1, and c-Fos. In signaling pathway, the phosphorylation of Akt, p38, c-Jun N-terminal kinases (JNK), extracellular signal-regulated kinases (ERK) and the expression of osteoclast-associated receptor (OSCAR), tartrate-resistant acid phosphates (TRAP), Integrin av, Integrin b3, Cathepsin K are suppressed, too. These result suggest that WEZJ may have therapeutic value for treating or preventing several bone diseases characterized by excessive bone destruction.

• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.247-256
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• 1999

A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.