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1.
A mutant form of the common beta-subunit of the GM-CSF, interleukin-3 (IL3) and IL5 receptors is activated by a 37 residue duplicated segment which includes the WSXWS motif and an adjacent, highly conserved, aliphatic/basic element. Haemopoietic expression of this mutant, hbeta(c)FIDelta, in mice leads to myeloproliferative disease. To examine the mechanism of activation of this mutant we targetted the two conserved motifs in each repeat for mutagenesis. Here we show that this mutant exhibits constitutive activity in BaF-B03 cells in the presence of mouse or human GM-CSF receptor alpha-subunit (GMRalpha) and this activity is disrupted by mutations of the conserved motifs in the first repeat. In the presence of these mutations the receptor reverts to an alternative conformation which retains responsiveness to human IL3 in a CTLL cell line co-expressing the human IL3 receptor alpha-subunit (hIL3Ralpha). Remarkably, the activated conformation is maintained in the presence of substitutions, deletions or replacement of the second repeat. This suggests that activation occurs due to insertion of extra sequence after the WSXWS motif and is not dependent on the length or specific sequence of the insertion. Thus hbeta(c) displays an ability to fold into functional receptor conformations given insertion of up to 37 residues in the membrane-proximal region. Constitutive activation most likely results from a specific conformational change which alters a dormant, inactive receptor complex, permitting functional association with GMRalpha and ligand-independent mitogenic signalling.  相似文献   

2.
To assess the role that polymorphisms of cytokine genes play in genetic predisposition to chronic obstructive pulmonary disease (COPD), the allele and genotype distributions of IL1B, IL1RN, TNFA, LTA, IL6, IL8, and IL10 were studied in COPD patients (N = 319) and healthy individuals (N = 403), residents of Ufa, Bashkortostan. Genotype IL1RN*2/IL1RN*2 of IL1RN was identified as a risk factor for COPD, its frequency being 9.80% in the COPD patients and 4.67% in the healthy subjects (x 2 = 5.45, df = 1, P = 0.02, OR = 2.21). Genotype GG of the LTA polymorphism A252G was significantly more common in the COPD patients than in the controls (7.84% vs. 3.72%; x 2 = 5.00, df = 1, P = 0.026). In patients with COPD stage IV, the frequency of this genotype was twice as high as in those with COPD stages II and III (11.18% vs. 4.79%; x 2 = 3.08, df = 1, P = 0.08). Genotype GG of the TNFA polymorphism G(?308)A in combination with genotype AA of the LTA polymorphism A252G was significantly less frequent in the COPD patients than in the healthy subjects (38.55% vs. 46.93%; x 2 = 8.82, df = 1, P = 0.0039). Genotype GG of the IL6 polymorphism G(?174)C was more frequent in the patients with COPD stage IV (43.75% vs. 31.54% in the patients with COPD stages II and III, x 2 = 4.15, P = 0.042). No significant differences were found between the groups of COPD patients and healthy subjects concerning the genotype frequencies of the polymorphisms T(?511)C and T3953C of IL1B, G(?308)A of TNFA, G(?174)C of IL6, A(?251)C of IL8, and C(?627)A of IL10.  相似文献   

3.
IL 3 and IL 6 do not induce bone resorption in vitro   总被引:5,自引:0,他引:5  
B E Barton  R Mayer 《Cytokine》1990,2(3):217-220
Bone resorption in vitro and in vivo can be induced by interleukin 1 (IL 1) and tumor necrosis factor (TNF), both of which are potent inflammatory cytokines. Additionally, there are other factors produced by cells which can active osteoclasts. Because diverse factors are involved in bone resorption, we examined the role of two other inflammatory cytokines, IL 3 and IL 6. IL 3 has been shown to induce the formation of osteoclast-like cells from precursors, while IL 6 is a potent mediator of inflammatory responses. Osteoclast activity in neonatal mouse calvaria was measured as 45Ca released into the supernatant fluid following a 48 hr incubation period with cytokine. Our results show that while parathyroid hormone (PTH) and IL 1 are potent inducers of bone resorption, neither IL 3 nor IL 6 displayed such activity.  相似文献   

4.
The signalling of cytokine receptors plays a crucial role in regulating tolerance and immunity. Impaired immunological processes result in autoimmune inflammation that target the hair follicles, causing many hair disorders, mainly alopecia areata (AA). Therefore, polymorphisms in cytokine receptor genes are suggested to have a significant impact on the pathogenesis of AA, a disease with a multifactorial basis and uncertain etiology. In the present study, 152 AA patients of the Jordanian population were investigated for their genetic susceptibility to develop AA compared to 150 control subjects. Genomic DNA extraction and genotyping had conducted for IL17RA (rs879575, rs2229151, and rs4819554), IL2RA (rs3118470), IL23R (rs10889677), and IL31RA (rs161704) using the Sequenom MassARRAY® system. The allele frequency of IL17RA rs879575 is significantly higher in patients, while no statistical differences were found for IL2RA, IL23R, and IL31RA SNPs. Also, the recessive model of IL31RA rs161704 showing that AA genotype is significantly associated with AA development. To date, there is no published data regarding the association between AA and the selected genetic variants in our population. However, this study's findings assert that SNPs of IL17RA and IL31RA are linked to AA susceptibility in Jordanian patients.  相似文献   

5.
The genomic nucleotide sequence and chromosomal position of the interleukin 5 (IL5) gene has been described for the model marsupial Macropus eugenii (tammar wallaby). A 272 base pair genomic IL5 polymerase chain reaction (PCR) product spanning exon 3, intron 3, and exon 4 was generated using stripe-faced dunnart (Sminthopsis macroura) DNA. This PCR product was used to isolate a genomic lambda clone containing the complete IL5 gene from a tammar wallaby EMBL3 lambda library. Sequencing revealed that the tammar wallaby IL5 gene consists of four exons separated by three introns. Comparison of the marsupial coding sequence with coding sequences from eutherian species revealed 61 to 69% identity at the nucleotide level and 48 to 63% identity at the amino acid (aa) level. A polymorphic complex compound microsatellite was identified within intron 2 of the tammar wallaby IL5 gene. This microsatellite was also found in other marsupials including the swamp wallaby, tree kangaroo, stripe-faced dunnart, South American opossum, brushtail possum, and koala. Fluorescence in situ hybridization using DNA from the IL5 clone on tammar wallaby chromosomes indicated that the IL5 gene is located on Chromosome 1.  相似文献   

6.
The purpose of this study was to investigate the possible roles of the cytokines genes in the development of chronic obstructive pulmonary disease (COPD). Polymorphisms in the genes encoding IL1B, IL1RN, TNFA, LTA, IL6, IL8 H IL10 were investigated in COPD patients (N = 319) and healthy individuals (N = 403) living in Ufa, the Republic of Bashkortostan. We observed that IL1RN*2/IL1RN*2 genotype of ILRN gene was associated with susceptibility for COPD (9.8% vs. 4.67%; chi(2)= 5.45, df= 1, P = 0.02; OR = 2.21). Analysis of the LTA gene polymorphic locus A252G showed that in patients with COPD, the frequency of the GG genotype was significantly higher than that in the control group (7.84% vs. 3.72%; chi(2) = 5.00, df= 1, P = 0.025). The increase of this genotype was significant in case of stage IV of COPD (11.18% vs. 4.79%; chi(2) = 3.075, df= 1, P = 0.07). Frequency of genotype combination TNFA-308 G/G and LTA252 A/A significantly decreased in COPD group (38.55% vs. 46.93% in control group; chi(2) = 8.82, df= 1, P = 0.0039). The frequency of GG genotype of the IL6 gene was higher in the patients with stage IV of COPD (43.75% vs. 31.54%, chi(2) = 4.14, P = 0.041). Our results indicate that the genotype frequency of the T(-511)C, T3953C of IL1B, G(-308)A of TNFA, G(-1 74)C of IL6, A(-251)C of IL8 and C(-627)A of ILl0 genes polymorphisms was similar in COPD and healthy control groups.  相似文献   

7.
To gain insight into IL5 receptor subunit recruitment mechanism, and in particular the experimentally elusive pathway for assembly of signaling subunit beta(c), we constructed a soluble beta(c) ectodomain (s(beta)(c)) and developed an optical biosensor assay to measure its binding kinetics. Functionally active s(beta)(c) was anchored via a C-terminal His tag to immobilized anti-His monoclonal antibodies on the sensor surface. Using this surface, we quantitated for the first time direct binding of s(beta)(c) to IL5R(alpha) complexed to either wild-type or single-chain IL5. Binding was much weaker if at all with either R(alpha) or IL5 alone. Kinetic evaluation revealed a moderate affinity (0.2-1 microM) and relatively fast off rate for the s(beta)(c) interaction with IL5:R(alpha) complexes. The data support a model in which beta(c) recruitment occurs with preformed IL5:R(alpha) complex. Dissociation kinetics analysis suggests that the IL5-alpha-beta(c) complex is relatively short-lived. Overall, this study solidifies a model of sequential recruitment of receptor subunits by IL5, provides a novel biosensor binding assay of beta(c) recruitment dynamics, and sets the stage for more advanced characterization of the roles of structural elements within R(alpha), beta(c), and cytokines of the IL5/IL3/GM-CSF family in receptor recruitment and activation.  相似文献   

8.
Induction of IL 2 responsiveness in a murine IL 3-dependent cell line   总被引:12,自引:0,他引:12  
A mouse IL 3-dependent cell line, FD.C/1, can be induced to IL 2 growth responsiveness by culture in IL 2-conditioned culture medium. The IL 2-dependent cell lines derived by this procedure have been designated FD.C/2 cells. Once established, the FD.C/2 cells respond to human, rat, and mouse IL 2. When cultured with murine IL 3, FD.C/2 cells did not proliferate, appearing to accumulate in the G1 phase of the cell cycle. Other human and mouse lymphokines failed to stimulate FD.C/2 cell growth. The growth dependence of FD.C/2 cells on IL 2 could not be reversed to IL 3. Cell lines derived by these procedures could provide in vitro models for hemopoietic differentiative events.  相似文献   

9.
The effect of cyclic AMP-elevating agents on mitogen-stimulated IL2 production was examined. Prostaglandin E2 (PGE2) inhibited IL2 production by human peripheral blood T cells stimulated with PHA. In contrast, PGE2 did not inhibit PHA-stimulated IL2 production by the human leukemic T cell line. Jurkat, and often slightly enhanced IL2 production by those cells. Other cyclic adenosine monophosphate (cAMP) elevating agents (forskolin, isoproterenol, and the cAMP analogue, dibutyryl cAMP) also inhibited lectin-stimulated IL2 production by T cells, but could not inhibit IL2 production by Jurkat cells. Of the cAMP-elevating agents examined, only cholera toxin (CT) inhibited IL2 production by both Jurkat cells and peripheral blood T cells. Although phorbol myristate acetate (PMA) greatly enhanced PHA-stimulated IL2 production by Jurkat cells. CT remained markedly inhibitory. The combination of PMA and the calcium ionophore, ionomycin, also induced IL2 production by Jurkat cells, and this was similarly suppressed by CT, suggesting that a step after initial second messenger generation was inhibited. A prolonged increase in intracellular cAMP levels was induced by CT in both T cells and Jurkat cells, but the maximal level and the length of elevation achieved in T cells were much less than those observed in Jurkat cells. In contrast, PGE2 caused only a modest and transient increase in intracellular cAMP levels in Jurkat cells compared to that noted with T cells. PGE2 induced a more marked and sustained increase in cAMP levels in Jurkat cells treated with isobutylmethylxanthine (IBMX), a phosphodiesterase inhibitor. Moreover, in the presence of IBMX, PGE2 caused a marked inhibition of IL2 production by PHA-stimulated Jurkat cells. Differences in the capacity of PGE2 to induce cAMP could not be explained by disparities in the level of cAMP phosphodiesterase activity as this was comparable in Jurkat cells and in T cells. Thus, these observations indicate that IL2 production by both peripheral T cells and Jurkat cells can be modulated by cAMP-elevating agents. The data suggest that the diminished capacity of PGE2 to inhibit IL2 production by Jurkat cells reflects both a diminished capacity of PGE2 to induce increases in cAMP levels in these cells and an increase in the threshold of cAMP required to inhibit Jurkat cells.  相似文献   

10.
In mice there are two forms of the beta chain used in the IL3 receptor system, betacom and betaIL3. betacom is used by the IL3, IL5 and GM-CSF receptors whereas betaIL3 is only used in the IL3 receptor. In this work an assay was developed to identify residues of beta1L3 that restrict IL5 activity. It was found that such residues reside within the 2nd CRM of the molecule. Furthermore, when residues in the betaIL3 B'-C' loop were replaced with betacom sequence a form of betaIL3 was produced that was able to respond to IL5. This region is also responsible for IL3 binding to betaIL3 in the absence of alpha chain. It is therefore an important structural motif of betacom and betaIL3 responsible for both ligand interaction and specificity.  相似文献   

11.
Mycobacterium avium ssp. paratuberculosis (MAP) infection causes a chronic granulomatous inflammatory condition of the bovine gut that is characterized by diarrhea, progressive weight loss, and emaciation, and ultimately leads to loss in productivity and profitability of dairy operations. The host cytokine machinery is known to play an important role in protecting against MAP infection. Therefore, the goal of the present study was to assess whether polymorphisms in candidate genes encoding important cytokines and cytokine receptors are associated with MAP infection status of dairy cattle. MAP infection status was evaluated based on serum and milk enzyme-linked immunosorbent assays (ELISAs) for MAP-specific antibodies. Twenty previously reported polymorphisms in genes encoding bovine interferon gamma (IFNG), IFNGR1, IFNGR2, IL22, IL22RA1, IL12RB1, IL12RB2, and IL23R were genotyped in a resource population of 446 dairy Holsteins with known MAP infection status, and logistic regression was used to assess the statistical association with a binomial MAP infection status phenotype. Four SNPs in IFNGR2, IL12RB1, IL12RB2, and IL23R were found to be associated with the MAP infection status of the resource population. These results underscore the importance of cytokines and their receptors in conferring protection against MAP infection and warrant further functional characterization of these associations.  相似文献   

12.
Inflammatory markers have consistently been associated with vascular disease. Evidence of genetic polymorphisms in inflammatory loci that predict severe carotid artery disease (CAAD) would suggest that this relationship is not secondary to other correlated factors, but related to inflammation itself. We examined the full common genetic variation in 42 inflammatory loci for prediction of severe CAAD versus ultrasound proven controls using a tagSNP approach. For selected loci, monocyte RNA levels were contrasted in subjects with and without CAAD. We confirm the association of IL6−174, FGB −455, and ALOX5 with CAAD and show that multiple ALOX5 SNPs independently predict CAAD. We provide evidence for previously unreported associations of SNPs in IL4R, NFKBIA, and PLG with CAAD, and weaker evidence for associations with CSF3, IL10RA, and VCAM1. The NFKBIA and IL10RA expression levels significantly differed between subjects with CAAD and controls. These results support a role for genetic variation related to inflammation in CAAD and a causal role for specific gene products. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   

13.
14.
To investigate the thyroid hormone metabolism in altered states of thyroid function, serum concentrations of 3, 3'-diiodothyronine (3, 3'-T2), 3', 5'-T2 and 3, 5-T2 as well as T4, T3 and rT3 were determined by specific radioimmunoassays in 17 hyperthyroid and 10 hypothyroid patients, before and during the treatment. Serum T4, T3, rT3, 3, 3'-T2 and 3', 5'-T2 concentrations were all higher in the hyperthyroid patients than in age-matched controls and decreased to the normal ranges within 3 to 4 months following treatment with antithyroid drugs. In the hypothyroid patients, these iodothyronine concentrations were lower than in age-matched controls and returned to the normal ranges after 2 to 3 months treatment with T4. In contrast, serum 3, 5-T2 concentrations in hyperthyroid patients (mean +/- SE : 4.0 +/- 0.5 ng/dl) were not significantly different from those in controls (3.9 +/ 0.4 ng/dl), although they tended to decrease in 3 of 6 patients after the antithyroid drug therapy. Serum 3, 5-T2 levels in the hypothyroid patients (3.8 +/- 0.6 ng/dl) were also within the normal range and showed no significant change following the T4 replacement therapy. However, serum 3, 5-T2 as well as 3, 3'T2 concentrations rose significantly with a marked rise in serum T3 following T3 administration, 75 micrograms/day for 7 days, in Graves' patients in euthyroid state.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
旨在利用简单的表达纯化工艺,获得纯度较高、有活性的重组免疫毒素IL3-PE38KDEL并对其物理学及免疫学性质进行鉴定。利用PQE30-IL3-PE38KDEL/SG12009工程菌表达重组免疫毒素IL3-PE38KDEL,在提取包涵体后经一步强阳离子柱层析得到纯度较高的免疫毒素复性纯化产物,用Westenblotting、质谱、氨基测序等先进技术对产物鉴定。结果显示,发酵后目的蛋白表达量占总菌体的17.56%,经强阳离子柱层析纯化复性后的目的蛋白纯度达到90%以上,Western blotting、质谱、氨基测序结果均表明,纯化产物分子量为54.9kD且具有相应的免疫学活性,序列与预期序列完全一致。纯化复性方法对重组免疫毒素IL3-PE38KDEL的生物性质及纯度有较大影响,因此选择一种适当的纯化复性方法至关重要。  相似文献   

16.
17.
The pathogenesis of stroke is associated with the immune and inflammatory responses. Cytokines, such as interleukin 10 (IL10), play an important role in the process of inflammation. To investigate whether IL10, IL10RA, and IL10RB polymorphisms are associated with the risk of ischemic stroke (IS), selected two IL10 SNPs (rs1518111 and rs1554286), three IL10RA SNPs (rs2256111, rs4252243, and rs2228054), and two IL10RB SNPs (rs999788 and rs2834167) were analyzed in 120 patients with IS and 285 control subjects. All IS patients were classified into the clinical subgroups, according to the levels of blood pressure (hypertension, present and absent), fasting plasma glucose (diabetes mellitus, present and absent), and lipids (dyslipidemia, present and absent). SNPStats and SPSS 18.0 program were used to obtain the odds ratios, 95 % confidence intervals, and P values. Multiple logistic regression models (codominant1, codominant2, dominant, recessive, and log-additive models) were performed to analyze the genetic data. Seven polymorphisms were not associated with the IS, but showed significant associations with hypertension, in the risk of IS. These results suggest that the IL10, IL10RA, and IL10RB genes may be contributed to the hypertension in the risk of IS in the Korean population.  相似文献   

18.
IL23/IL17 pathway plays an important role in the development of inflammatory bowel diseases (IBD). In general, the genes encoding the cytokines are genetically polymorphic and polymorphisms in genes IL23R and IL17 have been proved to be associated with its susceptibility to inflammatory diseases as well as cancer including colorectal cancer. Moreover, it has been shown that these interleukins are involved in anti-tumor or pro-tumor effects of various cancers. Previously, we showed that there is a significant association between IL17A, IL17F and IL23R polymorphisms as well as the occurrence of colorectal cancer and the clinical features of the disease. The purpose of the present work is to investigate an association between IL17A, IL17F and IL23R polymorphisms in 102 Tunisian patients with colorectal cancer treatment. The association was analyzed by statistical tools. We found that patients with mutated genotypes of IL17A G197A SNP could be a risk factor for the inefficiency of chemotherapy and radiotherapy. Unlike IL17F variant, patients with wild type genotypes require surgery and adjuvant chemotherapy. On the one hand, we found no evidence that supports a significant association between IL23R polymorphism and the combined genotypes of these three genes and the colorectal cancer treatment. On the other hand, we showed that there is an important interaction between IL17A/IL17F polymorphisms and the stage of the disease as well as its treatment. Finally, patients with IL17F wild type genotype highlighted that there is a valid longer OS without all treatments and with radiotherapy and a neoadjuvant chemotherapy. In contrast, we observed that there are no relationships between IL17A, IL23R and the survival of these patients neither with nor without the treatment. Our results suggest that polymorphisms in IL17A and IL17F genes may be a predictive source of colorectal cancer therapy type. Therefore, IL17F may serve as an independent prognostic factor for overall survival in patients with colorectal cancer.  相似文献   

19.
STAT5 activation underlies IL7 receptor-dependent B cell development   总被引:8,自引:0,他引:8  
Signals initiated by the IL7R are required for B cell development. However, the roles that distinct IL7R-induced signaling pathways play in this process remains unclear. To identify the function of the Raf and STAT5 pathways in IL7R-dependent B cell development, we used transgenic mice that express constitutively active forms of Raf (Raf-CAAX) or STAT5 (STAT5b-CA) throughout lymphocyte development. Both Raf-CAAX and STAT5b-CA mice exhibit large increases in pro-B cells. However, crossing the Raf-CAAX transgene onto the IL7R(-/-) background fails to rescue B cell development. In contrast, STAT5 activation selectively restores B cell expansion in IL7R(-/-) mice. Notably, the expansion of pro-B cells in STAT5b-CA mice correlated with an increase in cyclin D2, pim-1, and bcl-x(L) expression, suggesting that STAT5 directly affects pro-B cell proliferation and survival. In addition, STAT5 activation also restored B cell differentiation in IL7R(-/-) mice as determined by 1) the restoration of V(H) Ig gene rearrangement and 2) the appearance of immature and mature B cell subsets. These findings establish STAT5 as the key player entraining B cell development downstream of the IL7R.  相似文献   

20.
In the search for genes involved in type 1 diabetes (T1D), other than the well-established risk alleles at the human leukocyte antigen loci, we have investigated the association and interaction of polymorphisms in genes involved in the IL4/IL13 pathway in a sample of 90 Filipino patients with T1D and 94 controls. Ten single-nucleotide polymorphisms (SNPs), including two promoter SNPs in the IL4R locus on chromosome 16p11, one promoter SNP in the IL4 locus on chromosome 5q31, and four SNPs--including two promoter SNPs--in the IL13 locus on chromosome 5q31 were examined for association, linkage disequilibrium, and interaction. We found that both individual SNPs (IL4R L389L; odds ratio [OR] 0.34; 95% confidence interval [CI] 0.17-0.67; P=.001) and specific haplotypes both in IL4R (OR 0.10; 95% CI 0-0.5; P=.001) and for the five linked IL4 and IL13 SNPs (OR 3.47; P=.004) were strongly associated with susceptibility to T1D. Since IL4 and IL13 both serve as ligands for a receptor composed, in part, of the IL4R alpha chain, we looked for potential epistasis between polymorphisms in the IL4R locus on chromosome 16p11 and the five SNPs in the IL4 and IL13 loci on chromosome 5q31 and found, through use of a logistic-regression model, significant gene-gene interactions (P=.045, corrected for multiple comparisons by permutation analysis). Our data suggest that the risk for T1D is determined, in part, by polymorphisms within the IL4R locus, including promoter and coding-sequence variants, and by specific combinations of genotypes at the IL4R and the IL4 and IL13 loci.  相似文献   

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