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51.
Background
Immunoglobulin E (IgE) binds to high affinity receptor FcεRI numerously expressed on mast cells. Recent findings have revealed that IgE by itself may regulate various aspects of mast cell biology, however, detailed data is still limited.Methodology/Findings
Here, we have examined the influence of IgE alone, used at different concentrations, on mast cell activity and releasability. For the study we have employed in vivo differentiated mature tissue mast cells isolated from rat peritoneal cavity. Mast cells were exposed to IgE alone and then the release of preformed and de novo-synthesized mediators, surface FcεRI expression and mast cell migratory response were assessed. IgE by itself was found to up-regulate FcεRI expression and activate mast cells to degranulation, as well as de novo synthesis and release of cysteinyl leukotrienes and TNF. We have provided evidence that IgE alone also amplified spontaneous and CCL5- or TNF-induced migration of mast cells. Importantly, IgE was effective only at concentrations ≥ 3 µg/mL. A molecular basis investigation using an array of specific inhibitors showed that Src kinases, PLC/PLA2, MAP kinases (ERK and p38) and PI3K were entirely or partially involved in IgE-induced mast cell response. Furthermore, IgE alone stimulated the phosphorylation of MAP kinases and PI3K in rat mast cells.Conclusion
Our results clearly demonstrated that IgE by itself, at higher concentrations, influences mast cell activity and releasability. As there are different conditions when the IgE level is raised it might be supposed that in vivo IgE is one of the important factors modulating mast cell biology within tissues. 相似文献52.
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54.
Ole J Hamming Ewa Terczyńska‐Dyla Gabrielle Vieyres Ronald Dijkman Sanne E Jørgensen Hashaam Akhtar Piotr Siupka Thomas Pietschmann Volker Thiel Rune Hartmann 《The EMBO journal》2013,32(23):3055-3065
The IFNL4 gene is a recently discovered type III interferon, which in a significant fraction of the human population harbours a frameshift mutation abolishing the IFNλ4 ORF. The expression of IFNλ4 is correlated with both poor spontaneous clearance of hepatitis C virus (HCV) and poor response to treatment with type I interferon. Here, we show that the IFNL4 gene encodes an active type III interferon, named IFNλ4, which signals through the IFNλR1 and IL‐10R2 receptor chains. Recombinant IFNλ4 is antiviral against both HCV and coronaviruses at levels comparable to IFNλ3. However, the secretion of IFNλ4 is impaired compared to that of IFNλ3, and this impairment is not due to a weak signal peptide, which was previously believed. We found that IFNλ4 gets N‐linked glycosylated and that this glycosylation is required for secretion. Nevertheless, this glycosylation is not required for activity. Together, these findings result in the paradox that IFNλ4 is strongly antiviral but a disadvantage during HCV infection. 相似文献
55.
Małgorzata Jarmuz-Szymczak Kinga Pelinska Magdalena Kostrzewska-Poczekaj Ewa Bembnista Maciej Giefing Damian Brauze Marcin Szaumkessel Andrzej Marszalek Joanna Janiszewska Katarzyna Kiwerska Anna Bartochowska Reidar Grenman Witold Szyfter Krzysztof Szyfter 《Molecular biology reports》2013,40(7):4161-4171
We reinvestigated rearrangements occurring in region q13 of chromosome 11 aiming to: (i) describe heterogeneity of the observed structural alterations, (ii) estimate amplicon size and (iii) identify of oncogenes involved in laryngeal cancer progression as potential targets for therapy. The study included 17 cell lines derived from laryngeal cancers and 34 specimens from primary laryngeal tumors. The region 11q13 was analyzed by fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and gene expression microarray. Next, quantitative real time PCR was used for chosen genes to confirm results from aCGH and gene expression microarray. The observed pattern of aberrations allows to distinguish three ways, in which gain and amplification involving 11q13 region may occur: formation of a homogeneously staining region; breakpoints in/near 11q13, which lead to the three to sevenfold increase of the copy number of 11q13 region; the presence of additional copies of the whole chromosome 11. The minimal altered region of gain and/or amplification was limited to ~1.8 Mb (chr.11:69,395,184–71,209,568) and comprised mostly 11q13.3 band which contain 12 genes. Five, out of these genes (CCND1, ORAOV1, FADD, PPFIA1, CTTN) had higher expression levels in comparison to healthy controls. Apart from CCND1 gene, which has an established role in pathogenesis of head and neck cancers, CTTN, ORAOV1 and FADD genes appear to be oncogene-candidates in laryngeal cancers, while a function of PPFIA1 requires further studies. 相似文献
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Monika Lesicka Ewa Jabłońska Edyta Wieczorek Barbara Seroczyńska Leszek Kalinowski Jarosław Skokowski 《Chronobiology international》2013,30(8):1103-1114
ABSTRACTOne of the supposed mechanisms that may lead to breast cancer (BC) is an alteration of circadian gene expression and DNA methylation. We undertook an integrated approach to identify methylation pattern of core circadian promoter regions in BC patients with regard to clinical features. We performed a quantitative methylation-specific real-time PCR analysis of a promoter methylation profile in 107 breast tumor and matched non-tumor tissues. A panel of circadian genes CLOCK, BMAL1, PERIOD (PER1, 2, 3), CRYPTOCHROME (CRY1, 2) and TIMELESS as well as their association with clinicopathological characteristics were included in the analysis. Three out of the eight analyzed genes exhibited marked hypermethylation (PER1, 2, 3), whereas CLOCK, BMAL1, CRY2 showed significantly lower promoter CpG methylation in the BC tissues when compared to the non-tumor tissues. Among variously methylated genes we found an association between the elevated methylation level of PERs promoter region and molecular subtypes, histological subtypes and tumor grading of BC. Methylation status may be associated with a gene expression level of circadian genes in BC patients. An aberrant methylation pattern in circadian genes in BC may provide information that could be used as novel biomarkers in clinics and molecular epidemiology as well as play an important role in BC etiology. 相似文献
58.
Ewa Rębacz-Maron Irena Baranowska-Bosiacka Izabela Gutowska Natalia Krzywania Dariusz Chlubek 《Biological trace element research》2013,156(1-3):91-95
The present study aimed at analysing the content of fluorine (F), calcium (Ca) and magnesium (Mg) in the hair of young male students (n?=?52) of a secondary school in Mafinga in Tanzania (Africa) who participated in anthropological examinations. Ca and Mg concentrations were determined using atomic absorption spectrophotometer while F levels using a potentiometric method. F in the hair of boys from older group (≥16 years old; n?=?24) was significantly higher than in the younger group (<16 years old; n?=?28) versus Ca and Mg levels. High carbohydrate diet was predominant—mainly based on corn or bean and meat served once a week, with few fruit and raw vegetables. Collective catering in the dormitory reflected habits and culinary preferences at home. The lack of balanced diet, with majority of the nutritional energy supplied by easily accessible and cheap carbohydrates, was reflected in dietary deficiencies, characterised, among others, by visible skin conditions and tooth decay. 相似文献
59.
Magdalena Chelchowska Jadwiga Ambroszkiewicz Katarzyna Jablonka-Salach Joanna Gajewska Tomasz M. Maciejewski Ewa Bulska Teresa Laskowska-Klita Jerzy Leibschang 《Biological trace element research》2013,155(2):169-175
To assess the effect of lead exposure from cigarette smoke on fetal growth, blood lead concentrations were measured using inductively coupled plasma mass spectrometry in 150 healthy pregnant women. Mean lead concentrations in plasma and whole blood were significantly higher in the smoking group compared with the nonsmoking group in each trimester of pregnancy (p?<?0.001). Logistic regression analysis showed the highest impact of the number of cigarettes smoked per day for serum lead concentration (β?=?0.238; p?<?0.05), while in whole blood, it was duration of smoking before conception (β?=?0.297; p?<?0.001). Birth weight of the smoking mothers' infants was significantly lower (mean?±?SEM, 3,192?±?50.8 and 3,569?±?49.6 g, respectively; p?<?0.001) and negatively correlated with lead levels in plasma (r?=??0.38; p?<?0.001) and in whole blood (r?=??0.27; p?<?0.001). Therefore, it is suggested that smoking during pregnancy increases lead concentrations in maternal blood. Fetal exposure to low doses of lead in utero may be a serious risk factor causing lower birth weight. 相似文献
60.
Ewa Kaczorek Karolina Cieślak Katarzyna Bielicka-Daszkiewicz Andrzej Olszanowski 《Indian journal of microbiology》2013,53(1):84-91
Twelve different bacteria–yeast combinations were tested for determination of their ability to biodegrade diesel oil. The cell surface properties of the bacterial and yeast strains were correlated with the type of carbon source used in the experiments. The highest biodegradation of diesel oil after 7 days was obtained for the following combinations: Aeromonas hydrophila MR4–Yarrowia lipolytica EH 56 (87 %) and Xantomonas maltophila MRP7–Candida maltosa EH15 (90 %). Degradation performances of 10 of 12 combinations were enhanced by the presence of rhamnolipids. The highest increases were observed for A. hydrophila MR4–C. maltosa EH15 (from 34 to 67 %), A. hydrophila MR4–C. maltosa EH60 (from 47 to 76 %) and for Pseudomonas stutzeri MR7–C. maltosa EH60 (from 29 to 79 %). The addition of rhamnolipids to the system reduces the removal time of diesel oil from the contaminated water and changes the microbial adhesion to hydrocarbons. Modification of the cell surface of the tested strain during biodegradation is a very important factor determining the removal of hydrophobic compounds. 相似文献