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71.
Elevated interleukin-18 levels in bronchoalveolar lavage fluid of patients with eosinophilic pneumonia 总被引:3,自引:0,他引:3
BACKGROUND: Interleukin (IL)-18 can induce Th2 cytokine production particularly in collaboration with IL-2. Accumulation of Th2 cells and increased levels of Th2 cytokines are found in bronchoalveolar lavage fluid (BALF) from patients with eosinophilic pneumonia (EP). To evaluate the role of IL-18 in the pathogenesis of EP, we measured the concentration of IL-2, IL-12, IL-18, and Th2 cytokines in BALF from patients with EP. METHODS: The concentrations of interferon (IFN)-gamma, IL-2, IL-5, IL-10, IL-12, IL-13, and IL-18 in BALF were measured in patients with idiopathic acute eosinophilic pneumonia (AEP), with idiopathic chronic eosinophilic pneumonia (CEP), with sarcoidosis and healthy volunteers (HV). RESULTS: The BALF concentrations of Th2 cytokines, IL-5, IL-10, and IL-13, were higher in patients with EP than in sarcoidosis and control. The IL-2 level in BALF was higher in EP than in sarcoidosis and control. The IL-18 and IL-12 (p40 + p70) levels were higher in patients with EP than sarcoidosis, while the level of IL-12 (p70) was below the detection limit in patients with EP. There was a significant correlation between IL-2 level and both IL-5 and IL-13 in BALF of patients with EP. CONCLUSIONS: Our findings suggest that IL-18 may contribute to Th2 cytokine-dominant responses in patients with EP in collaboration with IL-2. 相似文献
72.
The distributions of retrograde labeled cells in fields 17 and 18 and the fields 17/18 transitional zone were studied in both hemispheres of cats after microiontophoretic administration of horseradish peroxidase into individual cortical columns in fields 17, 18, 19, and 21a. The clustered organization of the internal connections of the cortical fields, the asymmetrical locations of labeled callosal cells relative to the injected columns, and the defined distribution of labeled cells in layers A of the lateral geniculate body suggested that eye-specific neuronal connections support binding of the visual hemifields separately for each eye. Application of marker to columns in fields 19 or 21a demonstrated disparate inputs from fields 17 and 18 and the fields 17/18 transitional zone. It is suggested that these connections may support the extraction of loci and stereoscopic boundaries located in the central sectors of the visual space.Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 89, No. 10, pp. 1281–1290, October, 2003. 相似文献
73.
Ectodermal dysplasias (EDs) are developmental disorders affecting tissues of ectodermal origin including hair, nails, teeth and sweat glands. Ectodermal dysplasia of hair, nails and teeth is a rare type of congenital disorder characterized by sparse and thin hair, dystrophic finger-and toenails and missing and abnormal teeth. In an effort to understand the molecular basis of this form of ED a family of Pakistani origin with an autosomal recessive pattern of inheritance was ascertained from a remote region in Pakistan. The clinical features of the affected individuals included thin and fine hair on the scalp, dystrophic and flat nails, absent or sparse eyebrows and eyelashes, missing and abnormal teeth, and thin body hair. A human genome scan carried out using microsatellite markers mapped the disease locus in this family to chromosome 18q22.1–18q22.3. A maximum two-point LOD score of 2.73 (θ= 0.0) was obtained at marker D18S541. Multipoint linkage analysis resulted in a maximum LOD score of 3.42 obtained with several markers, including D18S1125, ATA82B02, D18S848, D18S488, D18S1091, and D18S485, which supported the linkage. The linkage interval is flanked by markers D18S857 and D18S815, which corresponds to a region of 17.32 cM according to Rutgers combined linkage and physical map (build 36). This region covers 8.63 Mb according to the sequence-based physical map. Three candidate genes, CDH7, CDH19 and ZNF407 , from the linkage interval were sequenced and found to be negative for functional sequence variants. This study is the first step towards the identification of a gene involved in hair, nails and teeth type ED. 相似文献
74.
The therapeutic effect of Interleukin-18 on hypertrophic scar through inducing Fas ligand expression
Xin Le Wei-Wei Wu 《Burns : journal of the International Society for Burn Injuries》2021,47(2):430-438
ObjectiveAmong downstream interleukin-18 (IL-18) targets, Fas ligand (FasL) in particular, has been strongly implicated in many conditions. Our study aims to explore the role of IL-18 in hypertrophic scar through enhancing FasL expression.MethodsIL-18 expression in hypertrophic scar tissues and normal tissues were explored by immunohistochemistry, qRT-PCR and Western blotting, and the expression of IL-18 in normal skin fibroblasts and hypertrophic scar fibroblasts by immunofluorescence. Hypertrophic scar fibroblasts treated with recombinant human IL-18 (rhIL-18) were assessed with MTT, Annexin V-FITC/PI, qRT-PCR, ELISA and western blotting. In the hypertrophic scar of rabbit ears, rhIL-18 was injected to determine histological changes with HE and Masson staining. Additionally, the scars were rated based on contour and overall severity using a visual analog scale scores (VAS).ResultsIL-18 was decreased in hypertrophic scar tissues and fibroblasts compared to normal skin tissues and fibroblasts, respectively. Decreased proliferation and increased apoptosis of hypertrophic scar fibroblasts were found after rhIL-18 treatment with enhanced expression of FasL, sFasL FADD, Caspase-8, Caspase-9 and Caspase-3 in a dose-dependent manner. The VAS and thickness of scars in rabbit ears was decreased as time went on after rhIL-18 treatment, with decreases in scar elevation index (SEI) and the increases in FasL expression.ConclusionIL-18 curbs proliferation and promotes apoptosis of hypertrophic scar fibroblasts by enhancing FasL expression. IL-18is a potential target for treatment of hypertrophic scar. 相似文献
75.
76.
Soos JM Polsky RM Keegan SP Bugelski P Herzyk DJ 《Clinical immunology (Orlando, Fla.)》2003,109(2):188-196
Natural antibodies to cytokines can be found in the sera of normal healthy individuals in the absence of specific immunostimulation. However, the function, impact, and purpose of natural antibody development have yet to be fully elucidated. Interleukin (IL)-18 is a cytokine that exerts proinflammatory activities and induces natural killer (NK) cell activity. Recombinant human IL-18 (rHuIL-18) is currently in development as a cancer immunotherapy. In this study, the presence of natural antibodies to IL-18 in the sera of normal humans and three nonhuman primate species was evaluated by electrochemiluminescence immunoassay (ECLIA). Of the human sera tested, 6 of 47 samples were positive for natural antibodies to IL-18. Of the nonhuman primate sera tested, 22 of 80 cynomolgus monkey samples, 4 of 31 rhesus monkey samples, and 2 of 20 chimpanzee samples were positive for natural antibodies to IL-18. Natural anti-IL-18 antibodies were neutralizing in 5 of 22 cynomolgus and 2 of 4 rhesus sera. None of the chimpanzee or human sera were able to neutralize IL-18 induction of interferon (IFN)-gamma in vitro. In vivo activity of rHuIL-18 was compared in IL-18 natural antibody-positive and -negative cynomolgus monkeys. The presence of natural antibodies to IL-18 did not alter rHuIL-18 systemic exposure levels, induction of neopterin, or induction of treatment-induced antibodies following intravenous administration of rHuIL-18. In conclusion, our data indicate that, as has been found with other cytokines, natural anti-IL-18 antibodies are relatively common. Moreover, natural anti-IL-18 antibodies do not appear to influence rHuIL-18 activity in vivo and are not predictive of a heightened immune response, suggesting that natural anti-IL-18 antibodies do not impact IL-18 therapy. Finally, our data suggest that the ability to detect natural anti-cytokine antibodies may be a useful measure of the adequacy of an assay for deployment in clinical trials. 相似文献
77.
T. Kumazawa O. Suzuki H. Seno Y. Ishikawa H. Hattori 《International journal of legal medicine》1990,103(7):479-485
Summary A simple and rapid method for isolation of seven antiepileptics (2 hydantoin, 2 oxazolidin, and 3 suximide derivatives) from urine and plasma is presented. Urine and plasma (1 ml) samples containing seven antiepileptics were mixed with distilled water (4 ml), and the sample solution was poured into a pretreated Sep-Pak C18 cartridge; this was washed with water and chloroform/methanol was passed through it to elute the antiepileptics. The eluate was mixed with isoamyl acetate and evaporated under a stream of N2. The drugs were detected by gas chromatography with fused silica capillary columns, splitless injection and flame ionization detection. Separation of the seven antiepileptics from each other and from impurities was satisfactory with the use of an SPB-1 capillary column. The detection limit for the seven antiepileptics with the present method was 0.1–1.0 g/ml urine or plasma. The recovery of the drugs from urine and plasma was more than 70% and 50%, respectively.
Offprint requests to: O. Suzuki 相似文献
78.
Objective: To study the treatment of experimental metastatic lung carcinoma by intratracheal injection of IL-18 gene recombinant adenovirus. Methods: (1)The mouse IL-18 mRNA was detected by RT-PCR, and the concentration of 1L-18 and associated cytokines in lung lavages and blood were determined by ELISA at different time points after intratracheal injection of IL-18 recombinant adenovirus. (2)The lung metastasis nodes, mouse survival periods and survival rates were evaluated. NK activity and CTL activity were determined by 51Cr 4 h release method. Results: (1)IL-18 mRNA was detectable in lung tissue 6 h after intratracheal use of IL-18 recombinant adenovirus, and the concentration of IL-18 in lung lavage was higher than that in peripheral blood. Neither IL-18 mRNA nor IL-18 was detectable in control group. (2) Intmtmcheal use of IL-18 recombinant adenovirus resulted in increased CTL and NK activity, longer survival time and higher survival rates compared with the control group, showing significant therapeutic effect on experimental lung metastasis. Conclusion: Intratracheal use of adenovirus vector containing IL-18 gene has therapeutic effect on the lung metastasis, denoting that gene therapy of lung diseases could be applied through airway directly with recombinant adenovirus. 相似文献
79.
目的 鉴定多嘧啶结合蛋白相关的剪切因子(polypyrimidine tract-binding protein-associated splicing factor, PSF)在髓系白血病细胞内的伴侣蛋白,探讨PSF在敏感HL60细胞和耐药的HL60/DOX细胞中易位细胞膜的模式和机制.方法: 通过脂质体瞬时转染PSF真核表达载体过表达PSF,进一步结合流式细胞术在转染后24 h,48 h,72 h检测PSF在细胞膜上的表达水平.构建链亲和素结合肽(streptavidin binding peptide,SBP)和PSF的融合表达载体,转染载体,过表达SBP-PSF融合蛋白.通过链亲和素磁珠共沉淀法和质谱分析,鉴定PSF在细胞内的伴侣蛋白.在慢病毒载体中插入角蛋白18 (cytokeratin 18,K18)干扰序列,转染293T细胞制备病毒液.用慢病毒感染HL60和HL60/DOX细胞,获得稳定干扰K18的细胞株.结合流式细胞术检测干扰K18的HL60和HL60/DOX细胞中细胞膜上PSF的表达水平,由此证实CK18在HL60和HL60/DOX细胞中协同转运PSF易位细胞膜机制的异同.结果: 瞬时过表达PSF后的24 h,48 h,72 h连续3 d检测细胞膜PSF表达水平,HL60敏感株细胞膜上PSF表达率分别为22.4%±3.5%, 37.9%±6.0%, 58.3%±8.8%;耐药株HL60/DOX细胞膜上PSF的表达率分别为4.7%±0.5%, 3.9%±0.6%, 2.9%±0.6%;各时间点下敏感株和耐药株的差异有统计学意义,P<0.01.免疫共沉淀和质谱证实K18为PSF在细胞内的伴侣蛋白.干扰K18的表达后,再次分析细胞膜PSF表达,发现PSF在敏感株细胞膜上的表达水平由原来的48.9%±5.4% 降至6.2%±1.0%;在耐药株细胞膜上的表达水平由9.11%±1.2%降至2.21%±0.51%.结论: K18是PSF在细胞内的伴侣蛋白,在敏感细胞中,K18与PSF相互作用可帮助PSF向细胞膜转运;而在耐药株中,由于该功能障碍导致PSF在胞内发生积累从而介导耐药性. 相似文献
80.
H. Lind MD D. Erlinge MD PhD J. Brunkwall MD PhD L. Edvinsson MD 《Clinical autonomic research》1995,5(4):191-197
Vascular smooth muscle contractile responses to neuropeptide Y, ,ß-methyleneATP and noradrenaline were studied in circular segments of isolated vessels with intact endotheliumin vitro from 12 patients with diabetes mellitus type 2 (NIDDM) and 12 control subjects. The dilatory effect of acetylcholine was used to test the function of the endothelium. Subcutaneous arteries and veins (diameter 0.1–1.1 mm) were obtained during surgery. There was no difference in contractile responses to noradrenaline or ,ß-methyleneATP between diabetic and control vessels. The contractile response to neuropeptide Y, however, was markedly reduced in the diabetic group. The maximal contractile effect (46.0 ± 14.0%,p < 0.05) but not the sensitivity to neuropeptide Y was significantly less in diabetic veins compared to control (107.5 ± 19.6%). Thus, the attenuation of neuropeptide Y responses was present in humans as previously observed in alloxan-induced diabetes mellitus in rabbits. There was no difference in the dilator effect of acetylcholine between the diabetic and the control group in any of the vessel types, indicating that the difference in vascular reactivity to neuropeptide Y was not endothelium-dependent. In conclusion, the present study has shown that the postjunctional effects of neuropeptide Y, a co-transmitter of the peripheral sympathetic nervous system, is selectively attenuated in diabetes mellitus. 相似文献