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101.
Carmi Y Rinott G Dotan S Elkabets M Rider P Voronov E Apte RN 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(6):3462-3471
Inflammatory cytokines modulate immune responses in the tumor microenvironment during progression/metastasis. In this study, we have assessed the role of IL-1 and IL-17 in the control of antitumor immunity versus progression in a model of experimental lung metastasis, using 3LL and B16 epithelial tumor cells. The absence of IL-1 signaling or its excess in the lung microenvironment (in IL-1β and IL-1R antagonist knockout [KO] mice, respectively) resulted in a poor prognosis and reduced T cell activity, compared with WT mice. In IL-1β KO mice, enhanced T regulatory cell development/function, due to a favorable in situ cytokine network and impairment in APC maturation, resulted in suppressed antitumor immunity, whereas in IL-1R antagonist KO mice, enhanced accumulation and activity of myeloid-derived suppressor cells were found. Reduced tumor progression along with improved T cell function was found in IL-17 KO mice, compared with WT mice. In the microenvironment of lung tumors, IL-1 induces IL-17 through recruitment of γ/δ T cells and their activation for IL-17 production, with no involvement of Th17 cells. These interactions were specific to the microenvironment of lung tumors, as in intrafootpad tumors in IL-1/IL-17 KO mice, different patterns of invasiveness were observed and no IL-17 could be locally detected. The results highlight the critical and unique role of IL-1, and cytokines induced by it such as IL-17, in determining the balance between inflammation and antitumor immunity in specific tumor microenvironments. Also, we suggest that intervention in IL-1/IL-17 production could be therapeutically used to tilt this balance toward enhanced antitumor immunity. 相似文献
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Bone marrow stem cells have been shown to differentiate into various phenotypes including cardiomyocytes, vascular endothelial cells and smooth muscle. Bone marrow stem cells are mobilized and home in to areas of injured myocardium where they are involved in tissue repair. In addition, bone marrow secretes multiple growth factors, which are essential for angiogenesis and arteriogenesis. In some patients, these processes are not enough to avert clinical symptoms of ischemic disease. Therefore, in vivo administration of an adequate number of stem cells would be a significant therapeutic advance. Unfractionated bone marrow derived mononuclear stem cells, which contain both hematopoietic and nonhematopoietic cells may be more appropriate for cell therapy. Studies in animal models suggest that implantation of different types of stem cells improve angiogenesis and arteriogenesis, tissue perfusion as well as left ventricular function. Several unanswered questions remain. For example, the optimal delivery approach, dosage and timing of the administration of cell therapy as well as durability of improvements need to be studied. Early clinical studies have demonstrated safety and feasibility of various cell therapies in ischemic disease. Randomized, double blind and placebo-controlled clinical trials need to be completed to determine the effectiveness of stem cell. 相似文献
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Mosyak L Wood A Dwyer B Buddha M Johnson M Aulabaugh A Zhong X Presman E Benard S Kelleher K Wilhelm J Stahl ML Kriz R Gao Y Cao Z Ling HP Pangalos MN Walsh FS Somers WS 《The Journal of biological chemistry》2006,281(47):36378-36390
Nogo receptor (NgR)-mediated control of axon growth relies on the central nervous system-specific type I transmembrane protein Lingo-1. Interactions between Lingo-1 and NgR, along with a complementary co-receptor, result in neurite and axonal collapse. In addition, the inhibitory role of Lingo-1 is particularly important in regulation of oligodendrocyte differentiation and myelination, suggesting that pharmacological modulation of Lingo-1 function could be a novel approach for nerve repair and remyelination therapies. Here we report on the crystal structure of the ligand-binding ectodomain of human Lingo-1 and show it has a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. The structure, together with biophysical analysis of its solution properties, reveals that in the crystals and in solution Lingo-1 persistently associates with itself to form a stable tetramer and that it is its LRR-Ig-composite fold that drives such assembly. Specifically, in the crystal structure protomers of Lingo-1 associate in a ring-shaped tetramer, with each LRR domain filling an open cleft in an adjacent protomer. The tetramer buries a large surface area (9,200 A2) and may serve as an efficient scaffold to simultaneously bind and assemble the NgR complex components during activation on a membrane. Potential functional binding sites that can be identified on the ectodomain surface, including the site of self-recognition, suggest a model for protein assembly on the membrane. 相似文献
107.
Despite extensive biochemical analyses, the biological function(s) of plant β-amylases remains unclear. The fact that β-amylases degrade starch in vitro suggests that they may play a role in starch metabolism in vivo. β-Amylases have also been suggested to prevent the accumulation of highly polymerized polysaccharides that might otherwise impede flux through phloem sieve pores. The identification and characterization of a mutant of Arabidopsis var. Columbia with greatly reduced levels of β-amylase activity is reported here. The reduced β-amylase 1 (ram1) mutation lies in the gene encoding the major form of β-amylase in Arabidopsis. Although the Arabidopsis genome contains nine known or putative β-amylase genes, the fact that the ram1 mutation results in almost complete loss of β-amylase activity in rosette leaves and inflorescences (stems) indicates that the gene affected by the ram1 mutation is responsible for most of the β-amylase activity present in these tissues. The leaves of ram1 plants accumulate wild-type levels of starch, soluble sugars, anthocyanin, and chlorophyll. Plants carrying the ram1 mutation also exhibit wild-type rates of phloem exudation and of overall growth. These results suggest that little to no β-amylase activity is required to maintain normal starch levels, rates of phloem exudation, and overall plant growth. 相似文献
108.
Gross Menachem Ashqar Fadi Sionov Ronit Vogt Friedman Michael Eliashar Ron Zaks Batya Gati Irith Duanis-Assaf Danielle Feldman Mark Steinberg Doron 《International microbiology》2022,25(1):177-187
International Microbiology - In this study, we aimed to develop a novel, sustained release varnish (SRV) for voice prostheses (VP) releasing chlorhexidine (CHX), for the prevention of biofilm... 相似文献
109.
Lyanne M. Kieneker Oliver Hartmann Andreas Bergmann Rudolf A. de Boer Ron T. Gansevoort Michel M. Joosten 《Biomarkers》2018,23(5):474-482
Background: Proenkephalin (pro-ENK) was recently found to be associated with low estimated glomerular filtration rate (eGFR). The association of pro-ENK with urinary albumin excretion (UAE), another marker for chronic kidney disease (CKD), has not been investigated. We examined the association of pro-ENK with eGFR and UAE as markers of CKD.Methods: We included 4375 subjects of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. CKDeGFR was defined as development of eGFR?<60?ml/min/1.73 m2 and CKDUAE as albuminuria?>30?mg/24?h.Results: Baseline median pro-ENK was 52.2 (IQR: 44.9–60.5) pmol/L. After a median follow-up of 8.4 (IQR: 7.9–8.9) years, 183 subjects developed CKDeGFR and 371 developed CKDUAE. The association of pro-ENK with CKDeGFR was modified by sex (Pinteraction?0.1), in such a way that after adjustment, the association only remained significant in men (adjusted hazard ratio per SD increase in 10log-transformed pro-ENK, 1.65; 95% CI: 1.15–2.36) and not in women (0.83; 0.58–1.20). No significant association was observed between pro-ENK and CKDUAE risk (0.83; 0.58–1.20).Conclusions: High pro-ENK is associated with increased risk of CKDeGFR in men, but not in women. No association of pro-ENK with CKDUAE was observed. These results should be interpreted with caution, since residual confounding and potential overfitting of models could have influenced the results. 相似文献
110.