BACKGROUND: Telomeres are simple repeats elements located at each end of the chromosomes of eukaryotic cells. The main function of telomeres is to cap the chromosome end and protect it from enzymatic attack. Telomerase that facilitates the synthesis of telomere has been detected in not only cancer, but also in precancerous lesion. In this study, we compared the telomerase expression between low-grade and high-grade gastric dysplasia. METHODS: The telomerase expression of 43 patients with gastric dysplasia (22 low-grade and 21 high-grade) was evaluated by immunohistochemical staining in tissues. RESULTS: The telomerase expression was much higher in the tissues from the patients with high-grade gastric dysplasia than in those tissues of the patients with low-grade gastric dysplasia. CONCLUSIONS: Activation of telomerase may be related with the malignant potentiality in gastric cells. Further studies are needed to define the role of telomerase in gastric tumorigenesis.
Carcinogenesis ; Eukaryotic Cells ; Humans ; Immunohistochemistry ; Telomerase* ; Telomere

The target of rapamycin (TOR) signaling pathway is a conserved pathway that regulates eukaryotic cell growth in response to environmental cues. Chemical genomic approaches that profile rapamycin sensitivity of yeast deletion strains have given insights into the function of TOR signaling pathway. In the present study, we analyzed the rapamycin sensitivity of yeast deletion library strains on synthetic medium. As a result, we identified 130 strains that are hypersensitive or resistant to rapamycin compared with wild-type cells. Among them, 36 genes are newly identified to be related to rapamycin sensitivity. Moreover, we found 16 strains that show alteration in rapamycin sensitivity between complex and synthetic media. We suggest that these genes may be involved in part of TOR signaling activities that is differentially regulated by media composition.
Cues ; Eukaryotic Cells ; Saccharomyces ; Saccharomyces cerevisiae ; Sirolimus ; Yeasts

Human cytomegalovirus (HCMV) glycoprotein H (gH) is one of target molecules in the human immune response to HCMV infection. This study was performed to rneasure the immune responses to HCMV gH in human sera by the expression of HCMV gH in eukaryotic cells. Amplified DNA from the gene encoding gH of HCMV by polymerase chain reaction was cloned into pcDNA3 to construct eukaryotic expression vector. Immunofluorescent staining revealed that the expressed gH in mammalian cells was reactive with the specific monoclonal antibody. Antibody titer in patient's sera with HCMV infection was measured with HCMV-infected fibroblasts and HCMV gH expressed in mammalian cells. Anti-HCMV gH antibody titer was higher in patient group than in healthy control group. There was no correlation between the antibody titer to the whole HCMV and neutralizing antibody titer, and between the antibody titer to whole HCMV and whole gH. Conclusively it is highly recommendable to use the defined antigen such as HCMV gH for the detection of antibody in HCMV-infected persons in the aspect of immunological properties.
Antibodies, Neutralizing ; Clone Cells ; Cytomegalovirus* ; DNA ; Eukaryotic Cells ; Fibroblasts ; Glycoproteins* ; Humans* ; Polymerase Chain Reaction

The kinesin superfamily is a class of motor proteins moving along microtubule filaments and playing essential roles in mitosis of eukaryotic cells. In the cancer biology, mitotic activity is an essential factor for development and metastasis of various cancers. Therefore, the inhibition of kinesin activity is suggested as an alternative cancer therapy. Accumulated clinical evidences have proved the potency of kinesin inhibitors in cancer treatments. In this review, we provided an overview of kinesins that play a critical role in the pathophysiology of various cancers and described the beneficial vs. side effects of their inhibitors that have been tested in both basic science and clinical studies.
Biology ; Eukaryotic Cells ; Kinesin* ; Microtubules ; Mitosis ; Neoplasm Metastasis ; Translational Medical Research*

BACKGROUND: Proteasomes are multi-subunit enzyme complexes present in the cytoplasm and nucleus of eukaryotic cells. Proteasomes are involved in the pathophysiological process resulting in development of many diseases. Release of proteasomes from lyzed erythrocytes has been suggested in recent reports. Accumulation of proteasomes in blood products could contribute to formation of storage lesions and have adverse effects on recipients; therefore, we conducted an analysis of changes in concentration of proteasomes in blood products during storage. METHODS: Concentrations of 20S proteasomes in supernatant of whole blood products obtained from eight healthy volunteers and in segments of 16 packed red blood cell (pRBC) units transfused to patients were measured by ELISA. Plasma samples containing several hemoglobin concentrations were prepared in order to assess the relationship between proteasome concentration and degree of hemolysis. RESULTS: Proteasome concentrations in whole blood products on day one of storage were significantly lower than those on day seven of storage and later (P<0.05). In segments of pRBC units, the proteasome concentration was 8.072+/-11.802 microg/mL (storage day: 13.8+/-4.7). Of the 32 pRBC units, two showed extremely high proteasome concentrations (36.662 and 62.798 microg/mL). Proteasome concentrations in plasma increased with increasing hemoglobin concentrations. CONCLUSION: During storage of whole blood products, except during the first seven storage days, levels of proteasome do not undergo significant change. However, hemolysis may be related to accumulation of proteasome. Further study to evaluate the effects of blood components containing high proteasome concentrations on recipients should be conducted.
Cytoplasm ; Enzyme-Linked Immunosorbent Assay ; Erythrocytes ; Eukaryotic Cells ; Hemoglobins ; Hemolysis ; Humans ; Plasma ; Proteasome Endopeptidase Complex

Autophagy constitutes a major catabolic hub for the quality control of intracellular entities of eukaryotic cells, and is emerging as an essential part of the host antiviral defense mechanism. However, in turn, viruses have evolved elegant strategies to co-opt various stages of the cellular autophagy pathway to establish virulence in vivo. This is particularly the case in the ubiquitous and persistent herpesvirus infection. In this review, I will focus on recent findings regarding the crosstalk between the herpes virus family and the autophagy pathway, with a look at the molecular mechanisms they use to disturb cells' autophagy regulation and eventually result in persistence and pathogenesis.
Autophagy ; Eukaryotic Cells ; Herpesviridae Infections ; Humans ; Immunity, Innate ; Quality Control ; Viruses

BACKGROUND: Intracellular antibody specific to hepatitis B virus X protein (HBx) might be useful for studying the role of HBx in hepatocellular carcinogenesis and HBV replication. METHODS: With variable region genes for H7 monoclonal anti-HBx Ab, we constructed a vector for bacterial expression of single chain Ab (scFv) and a vector for eukaryotic cell expression of it. The expression of H7 scFv and its binding activity against HBx was examined by immunoblotting and immunofluorescence microscopy. RESULTS: H7 scFv expressed in bacterial cells retained reactivity to HBx. We demonstrated its intracytoplasmic expression in CosM6 eukaryotic cells. CONCLUSION: This is the first study showing the expression of intracellular anti-HBx Ab in eukaryotic cells. H7 scFv may be a good tool to study the function of HBx in HBV infection
Carcinogenesis ; Eukaryotic Cells ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis* ; Immunoblotting ; Microscopy, Fluorescence

Autophagy is a fundamental cellular process in eukaryotic cells for maintaining homeostasis by degrading cellular proteins and organelles. Recently, the roles of autophagy have been expanded to immune systems, which in turn modulate innate immune responses. More specifically, autophagy acts as a direct effector for protection against pathogens, as well as a modulator of pathogen recognition and downstream signaling in innate immune responses. In addition, autophagy controls autoimmunity and inflammatory disorders by negative regulation of immune signaling. In this review, we focus on recent advances in the role of autophagy in innate immune systems.
Autoimmunity ; Autophagy ; Eukaryotic Cells ; Homeostasis ; Immune System ; Immunity, Innate ; Organelles ; Proteins ; Toll-Like Receptors

BACKGROUND: The heat shock proteins (HSPs) are stress-responsive genes present in all species and play a major role in many cellular processes. These proteins are highly conserved molecules whose expression is induced in eukaryotic cells by a variety of environmental stresses. These proteins can also be expressed in virally transformed cells and cancer cells. Especially, HSP70 is found at a higher level in growing cells than in resting cells. Sulphomucin is secreted by immature foveolar cells of stomach and expressed in gastric adenocarcinomas. Also, it is known that the population of sulphomucin-producing cells increases with long-lasting stress. The purpose of this study was to determine HSP70 and sulphomucin expressions in gastric adenocarcinoma and the significance of expressions. METHODS: Thirty-one paraffin-embeded surgical specimens of gastric adenocarcinomas were obtained from April 1992 to March 1995 and were selected for analysis. The expressions of HSP70 and sulphomucin were analyzed by immunohistochemical staining with HSP70 monoclonal antibody and the Spicer (HID) method. RESULTS: The expressions of HSP70 and sulphomucin were positive in 13 (42%) cases and 11 (35%) cases, respectively. The expression of HSP70 correlated with neither clinopathological factors nor sulphomucin expression. There was a significant correlation not only between sulphomucin expression and histologic differentiation (p=0.001) but also between disease-free survival and sulphomucin expression. CONCLUSIONS: Sulphomucin expression in gastric adenocarcinoma may be useful as a prognostic factor of gastric adenocarcinomas.
Adenocarcinoma* ; Disease-Free Survival ; Eukaryotic Cells ; Heat-Shock Proteins* ; Hot Temperature* ; HSP70 Heat-Shock Proteins* ; Stomach

Retroviral vector provide a highly efficient method for gene transfer into eukaryotic cells. This vector system can be divided into two components; the retroviral vector itself and the retroviral packaging cell line. The key improvement in the design of these two components are. focused on two aspects; the reduction of helper virus production and high titer-virus. We used PA317 for retrovirus packaging cell line, for its high producibility of viral titer, To test the ability of the vectors to generate high titer-virus, we have chosen four different retroviral vectors; LN, LNSX, LNCX and LXSN. To test easily the viral titer, we have made recombinant construction with CD4 and CD8, checked their viral titer and stained their surface expression. LXSN which contain SV40 early promoter in front of leo gene showed best results in viral transient transfection assay, dot blot assay and surface expression. In addition, recombinant containing CD8 generally showed much higher viral titration and surface expression than CD4.
Cell Line ; Eukaryotic Cells ; Helper Viruses ; Product Packaging ; Retroviridae ; Transfection ; Zidovudine*