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111.
目的研究白细胞介素-13(IL-13)处理小鼠支气管哮喘(哮喘)模型前后肺组织黏蛋白基因Muc5ac、凋亡相关蛋白Bcl-2和Bax表达的作用,探讨气道黏液过度分泌的机制.方法45只雄性BALB/c小鼠随机分为对照组、哮喘组和IL-13组,每组15只.用逆转录-聚合酶链反应(RT-PCR)方法和免疫组化法分别检测Muc5acmRNA、Muc5ac蛋白、Bcl-2蛋白以及Bax蛋白在肺组织的表达.结果哮喘组和对照组肺组织Muc5acmRNA分别为(0.1552±0.0057)和(0.0633±0.0013),Muc5ac蛋白分别为(0.8849±0.0257)和(0.1166±0.0064),两组比较差异均有统计学意义(P<0.01);IL-13组肺组织Muc5acmRNA和蛋白分别为(0.2807±0.0027)和(1.6138±0.0483),与哮喘组、对照组比较差异也均有统计学意义(P均<0.01).与对照组Bcl-2蛋白(0.3279±0.0136)、Bax蛋白(1.7284±0.0263)相比,哮喘组分别增加和降低(分别为0.8383±0.0310和0.8987±0.0106),两组差异均有统计学意义(P均<0.01);IL-13处理后可分别促进Bcl-2和Bax蛋白增加和降低(分别为1.6934±0.0229和0.3522±0.0152),其和哮喘组的差异均有统计学意义(P均<0.01);哮喘组和IL-13组小鼠肺组织Muc5acmRNA、蛋白表达与Bcl-2蛋白表达均呈直线正相关(P均<0.05),而与Bax蛋白表达则均呈直线负相关(P均<0.05).结论IL-13是引起哮喘气道黏液过度分泌的重要细胞因子,它可能通过改变Bcl-2和Bax的表达导致了上述病变. 相似文献
112.
Interleukin-2 (IL-2), secreted principally by activated helper T-cells, plays a pivotal role in the generation and regulation
of the immune response. The various biologic functions of IL-2 have been the focus of intensive study over the years and have
been well worked out. By contrast, an understanding of the intracellular signals coupled to the IL-2 receptor and responsible
for mediating IL-2 effects in T-cells is far less developed, and the role that protein kinase C (PKC) may play in the various
cellular responses to IL-2 receptor activation is unclear. In this article we will discuss IL-2, its receptors, and IL-2 signal
transduction in relation to the physiological roles PKC activation may play in IL-2-mediated activation of T-cells and other
hematopoietic cells. 相似文献
113.
The pro-inflammatory cytokine interleukin-1β (IL-1β) is released by cells during injury and stress, and increased neuronal expression of IL-1β is a feature of age-related neurodegeneration. We have recently reported that IL-1β has a biphasic effect on the K+-induced rise in intracellular Ca2+ concentration ([Ca2+]i) in cortical synaptosomes, exerting an inhibitory effect on the K+-induced rise in [Ca2+]i at lower (3.5 ng/mL) concentrations and a stimulatory effect on the K+-induced rise in [Ca2+]i at higher (100 ng/mL) concentrations. In the present study, we observed that the K+-induced rise in [Ca2+]i was inhibited to a similar extent by the lower concentration of IL-1β in cortical synaptosomes prepared from young (3-month-old), middle-aged (12-month-old) and aged (24-month-old) rats. In contrast, cortical synaptosomes prepared from the aged rats exhibited an increased susceptibility to the higher concentration of IL-1β, resulting in a marked elevation in [Ca2+]i. We propose that the age-related increase in neuronal concentration of IL-1β promotes a dramatic elevation in [Ca2+]i following membrane depolarization, thereby altering Ca2+ homeostasis and exacerbating neuronal vulnerability to excitotoxicity. 相似文献
114.
R. Sanchez L. Kanarek J. Koninkx H. Hendriks P. Lintermans A. Bertels G. Charlier E. Van Driessche 《Microbial pathogenesis》1993,15(6)
Enterotoxigenic Escherichia coli strains expressing F17 fimbriae bind to the intestinal mucosa of young calves. F17 fimbriae recognize receptors present in the mucus layer and the brush-border membranes from duodenum, jejunum and ileum. The adhesion of E. coli F17 can be inhibited by several glycoproteins. Adhesion is also inhibited by pretreatment of mucus and brush-border membranes with sodium metaperiodate. The use of glycoconjugates as potential adhesion-blockers is further discussed. 相似文献
115.
Jan K. Lacki Kamilla Klama Stefan H. Mackiewicz Urszula Mackiewicz Wolfgang Müller 《Inflammation research》1995,44(1):24-26
In order to evaluate the relationship between serum concentrations of interleukin-10 (IL-10), IL-6, and acute phase proteins in rheumatoid arthritis (RA) patients treated with methotrexate (MTX) or intramuscular gold (IMG) we determined IL-10, IL-6, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP) and alpha-1-antichymotrypsin (ACT) in the sera of 35 RA patients. IL-10 and IL-6 levels were evaluated using an enzyme-linked immunoassay (ELISA). AGP and ACT level were measured using rocket immunoelectrophoresis. IL-10 serum level was not increased in RA patients as compared to controls (58.7 ± 18.1 pg/ml vs. 57.2 ± 11.9 pg/ml). IL-6 level was significantly elevated (91.6 ± 46.9 pg/ml vs. 45 ± 19 pg/ml, p < 0.05). CRP was significantly increased as compared to healthy controls (35 ± 19 mg/l vs. 3 ± 2 mg/l, p < 0.05). Patients treated with MTX or IMG presented an increased level of IL-10 and decreased amounts of IL-6, as compared to those treated with NSAID only. However, only changes between patients treated with IMG and NSAID were found to be statistically significant. A good negative correlation between IL-10 and IL-6 serum level was found (r = –0.75, p < 0.05). A positive significant correlation between IL-6 serum level and CRP (r = 0.62, p < 0.05), AGP (r = 0.78, p < 0.05) and ACT (r = 0.45, p < 0.05) was established. On the other hand, a negative correlation between IL-10 and serum level of CRP (r = –0.76, p < 0.05), AGP (r = –0.64, p < 0.05) and ACT (r = –0.38, p < 0.05) was also observed. Moreover, these relationships were maintained when patients treated with MTX, IMG, or NSAID were analyzed independently. According to the data thus far obtained, it seems that IL-10 decreases IL-6 production, and thereby indirectly affects the acute phase response, decreasing CRP, AGP, and ACT concentration in RA patients.Abbreviations ACT
-1-antichymotrypsin
- AGP
1-acid glycoprotein
- APP
acute phase protein
- CRP
C-reactive protein
- CSF
colony stimulating factor
- IFN
interferon
- IL
interleukin
- IMG
intramuscular gold
- MTX
methotrexate
- NSAID
non-steroidal anti-inflammatory drug
- RA
rheumatoid arthritis 相似文献
116.
遗传过敏性皮炎患者血清IL—4水平与IgE的关系 总被引:4,自引:0,他引:4
钱起丰 《中华微生物学和免疫学杂志》1995,15(5):312-314
采用酶联免疫技术检测21例遗传过敏性皮炎患者血清白细胞介素4(IL-4)及IgE水平。实验结果发现,AD患者血清IL-4水平比正常人显著增高,并且与IgE密切相关。说明AD的发病与IL-4产一失调,从而导致B细胞合成IgE增加有关。人IL-4酶联免疫检测具有敏感、特异、简便、快速及结果可靠等特点。 相似文献
117.
Clinicopathological significant and prognostic influence of cadherin-17 expression in gastric cancer 总被引:5,自引:0,他引:5
Ito R Oue N Yoshida K Kunimitsu K Nakayama H Nakachi K Yasui W 《Virchows Archiv : an international journal of pathology》2005,447(4):717-722
Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our
serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas.
CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric
carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics
and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal
metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression
was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive
CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases
that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression
of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis. 相似文献
118.
应用mRNA麦胚无细胞体外转译体系,动态地观察了人参三醇皂甙(PTGS)对人淋巴结细胞IL-5基因表达的促进效应。结果表明,PTGS可以明显促进PHA活化人淋巴结细胞分泌IL-5,最大促进效应可达66.67%。PTGS+PHA共刺激后人淋巴结细胞浆IL-5 mRNA转译IL-5的量明显高于单纯PHA组,最大促进效应40%。上述结果首次证明PTGS对IL-5的促诱生效应是通过调节IL-5基因表达而实现的。 相似文献
119.
The focus of our research is to understand the immune response to foreign tissue. We believe that adichotomy exists within
the immune response to an allograft such that part of the response is dedicated to the protection of the graft. Nevertheless,
in a dominantly graft-aggressive environment, rejection typically ensues. In this article, we describe models that have been
set up to test directly the ability of potentially protective aspects of the immune response to prevent allograft rejection.
We discussour data in the context of a growing body of exciting and often controversial literature. 相似文献
120.
Martin C Al-Qaoud KM Ungeheuer MN Paehle K Vuong PN Bain O Fleischer B Hoerauf A 《Medical microbiology and immunology》2000,189(2):67-74
The pathways conferring immunity to human filariases are not well known, in part because human-pathogenic filariae do not
complete a full life cycle in laboratory mice. We have used the only fully permissive infection of mice with filariae, i.e.,
infection of BALB/c mice with the rodent filarial nematode Litomosoides sigmodontis. Our previous results showed that worm development is inversely correlated with Th2 cytokine production and eosinophilia.
The scope of the present study was to directly elucidate the role of interleukin-5 (IL-5) and eosinophils in controlling the
development of L. sigmodontis after vaccination and in primary infection. BALB/c mice immunized with irradiated third-stage larvae (L3) were confirmed
to have elevated IL-5 levels as well as high subcutaneous eosinophilia and to attack and reduce incoming larvae within the
first 2 days, resulting in 70% reduction of worm load. Treatment of vaccinated mice with anti-IL-5 antibody (TRFK-5) suppressed
both blood and tissue eosinophilia and completely abolished protection. This demonstrates, for the first time in a fully permissive
filarial infection, that IL-5 is essential for protection induced by irradiated L3 larvae. In contrast, in primary-infected
mice, anti-IL-5 treatment did not modify filarial infection within the 1st month, most likely because during primary infection
IL-5-dependent mechanisms such as subcutaneous eosinophilia are induced too late to disturb worm establishment. However, there
is a role for IL-5 late in primary infection where neutrophil-dependent worm encapsulation is also under the control of IL-5.
Received: 30 March 2000 相似文献