Resistin is elevated in cystic fibrosis sputum and correlates negatively with lung function

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Molecular simplification of lipid A structure: TLR4-modulating cationic and anionic amphiphiles

A growing body of data suggests that therapies based on Toll-like receptors (TLR) targeting, in particular TLR4, holds promise in curing autoimmune and inflammatory pathologies still lacking specific treatment, included several rare diseases. While TLR4 activators (agonists) have already found successful clinical application as vaccine adjuvants, the use of TLR4 blockers (antagonists) as antisepsis agents or as agents against inflammatory diseases (including arthritis, multiple sclerosis, neuroinflammations) and cancer is still at a preclinical phase of development. This minireview focuses on recent achievements on the development of TLR4 modulators based on lipid A structure simplification, in particular on compounds having disaccharide or monosaccharide structures. As the TLR4 activity of natural TLR4 ligands (lipopolysaccharide, LPS and its biologically active part, the lipid A) depends on both the structure of endotoxin aggregates in solution and on single-molecule interaction with MD-2 and CD14 receptors, the rational design of TLR4 modulators should in principle take into account both these factors. In the light of the most recent advances in the field, in this minireview we discuss the structure–activity relationship in simplified lipid A analogs, with cationic or anionic amphiphilic structures.     

TLR9在不同胎龄新生儿脐血中的表达变化

目的 通过观察早产儿不同胎龄Toll样受体9（TLR9）的表达，探讨早产儿免疫功能低下的机制。方法 采集2010年7月至2014年6月在上海市嘉定区妇幼保健院产科出生的活产新生儿的脐血229份，按胎龄分为4组，28~31周组，31~34周组，34~37周组，≥37周组，采用流式细胞术和实时荧光定量PCR方法，分别检测其TLR9的蛋白和mRNA表达情况，了解其与胎龄之间的关系，并分析mRNA和蛋白表达间的相关性。结果 TLR9阳性细胞率在28~31周组，31~34周组，34~37周组，≥37周组分别为（15.93±6.23）%，（11.63±6.70）%，（13.66±6.88）%，（20.51±12.06）%；其在胎龄28~31周较高，至31~34周逐渐下降至最低，两组差异有统计学意义（P<0.05）；34~37周后TLR9阳性细胞率表达逐渐升高，至≥37周达最高，两胎龄组比较，差异具有统计学意义（P<0.05）。31~37周间新生儿脐血TLR9阳性细胞率与胎龄呈正相关（r=0.273，P=0.006）。TLR9 mRNA表达在28~31周组，31~34周组，34~37周组，≥37周组分别为（4.95±3.44）%，（8.89±8.49）%，（13.91±10.92）%，（7.19±7.11）%；其在28~36周逐渐升高，与胎龄呈正相关（r=0.355，P< 0.001）。≥37周TLR9 mRNA表达量下降，该值虽高于28~31周，但差异无统计学意义（P>0.05）。相关性分析表明，同胎龄时期同样本新生儿的TLR9 mRNA和TLR9阳性细胞率之间存在负相关（r=-0.227，P=0.011）。结论 TLR9阳性细胞率和TLR9 mRNA表达在不同胎龄组新生儿间有差异，TLR9阳性细胞率表达在31~37周间随着胎龄的增加而增加，TLR9 mRNA在28~36周间随着胎龄的增加而增加。     

急性出血坏死性胰腺炎肝损伤中TLR2/4mRNA的表达及氯喹的干预效应

目的： 研究急性出血坏死性胰腺炎（AHNP）肝损伤中Toll-样受体(TLR)2/4mRNA表达的变化及氯喹的干预效应。 方法：采用逆行胰胆管牛磺胆酸钠（TAC）注射造成大鼠AHNP肝损伤动物模型。动物分为假手术组（S组）、胰腺炎组和氯喹（CQ）治疗组。后2组于术后3，6，12 h分批剖杀，S组于术后6 h剖杀。观察血清淀粉酶、ALT和AST及肝组织NO和TNF-α的变化，RT-PCR方法检测各组不同时点肝组织TLR2和TLR4mRNA的表达。 结果：相对于S组，胰腺炎组大鼠3 h肝组织TLR2和TLR4mRNA表达开始增高，术后6～12 h肝组织TLR2和TLR4mRNA表达迅速达到峰值（P<0.05），肝损伤加重，血清淀粉酶升高，肝组织TNF-α浓度升高，NO浓度逐渐降低（P<0.05）；相对胰腺炎组，CQ治疗组TLR2/4mRNA表达降低（P<0.05），肝损伤程度减轻，血清淀粉酶降低，肝组织TNF-α浓度降低，NO浓度显著升高（P<0.05）。 结论：AHNP大鼠肝组织内TLR2和TLR4的基因表达上调；其表达增高可能在AHNP肝损伤的发生、发展中起重要作用。氯喹对大鼠AHNP过程中肝损伤可能有保护作用。     

Bacterial ghosts (BGs)—Advanced antigen and drug delivery system

Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy.     

Common human Toll-like receptor 9 polymorphisms and haplotypes: association with atopy and functional relevance

BACKGROUND: Toll-like receptor 9 (TLR9) is a pattern-recognition receptor that detects unmethylated CpG motifs prevalent in bacterial and viral DNA. TLR9 stimulation is a key event after bacterial infection, triggering innate immunity and T-helper type 1 skewed adaptive immunity. Synthetic CpG-oligodeoxynucleotides (CpG-ODNs) represent a promising and novel class of immune adjuvants for allergy treatment, vaccination, and cancer therapy. However, common functional TLR9 gene variants could interfere with the clinical utilization of CpG-ODN in immunotherapy. Recently, a possible association of TLR9 polymorphism C-1237T with asthma has been reported. OBJECTIVE: The aim of the present study was to investigate whether TLR9 polymorphisms or haplotypes have functional relevance and are associated with atopy. METHODS: We genotyped five common TLR9 single-nucleotide polymorphisms (SNPs) in promoter, exon, and intron regions of the gene in 527 healthy blood donors, and estimated four common haplotypes. The total IgE and specific IgE levels against the most common aeroallergens were measured (n=303). IFN-alpha production by plasmacytoid dendritic cells (pDCs) was analysed after stimulation with TLR9 ligand CpG-ODN (n=220). RESULTS: No significant influence of common TLR9 polymorphisms and haplotypes on the total and specific IgE levels was found. Functional analysis of CpG-ODN-induced IFN-alpha did not indicate a significant role for common TLR9 gene polymorphisms in TLR9 function. CONCLUSION: We conclude that common genetic differences in the TLR9 gene exert no major influence on allergy susceptibility, and are unlikely to have on impact on clinical application of CpG-ODNs.     

TLR在小鼠胸腺中的表达及其在胸腺细胞发育中的可能作用

检测体外培养和体内发育过程中,胎鼠胸腺处于不同发育阶段时Toll样受体(TLR)的表达,阐明TLR表达量与胸腺细胞发育相关性,为TLR和胸腺细胞发育分化相关研究提供基础数据。无菌取15d胎龄胎鼠胸腺进行体外培养(FTOC),在培养不同时间点(2d,4d,6d),检测处于不同发育期胸腺TLR的表达;同时在孕期不同天数(15~19d),分别取胎鼠胸腺,检测在体内发育过程中胸腺TLR的表达;在FTOC中加入二脱氧鸟苷培养6d以制备胸腺基质细胞,检测基质细胞与胸腺细胞TLR表达情况。结果:小鼠胸腺中检测到多种TLR。FTOC培养中:培养第2天(F2)开始检测到各种TLR,到培养第6天(F6),TLR1,TLR3,TLR6,TLR7,TLR8明显上调,而TLR4,TLR5保持低水平,TLR4在培养第6天又下降;体内发育过程中:TLR6表达量随胎龄增加有较明显上调,TLR1,TLR3-8保持低水平表达;TLR2,TLR9体内体外都未检测到明显表达。在对胸腺细胞与基质细胞TLR表达比较中发现TLR1,TLR5,TLR6,TLR7高表达于胸腺细胞。胎鼠胸腺表达某些TLR,并且在发育不同阶段表达量有所改变,提示TLR可能参与胸腺细胞的发育过程。     

Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling

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TLR2 as an essential molecule for protective immunity against Toxoplasma gondii infection

To investigate the role of the Toll-like receptor (TLR) family in host defense against Toxoplasma gondii, we infected TLR2-, TLR4- and MyD88-deficient mice with the avirulent cyst-forming Fukaya strain of T. gondii. All TLR2- and MyD88-deficient mice died within 8 days, whereas all TLR4-deficient and wild-type mice survived after i.p. infection with a high dose of T. gondii. Peritoneal macrophages from T. gondii-infected TLR2- and MyD88-deficient mice did not produce any detectable levels of NO. T. gondii loads in the brain tissues of TLR2- and MyD88-deficient mice were higher than in those of TLR4-deficient and wild-type mice. Furthermore, high levels of IFN-gamma and IL-12 were produced in peritoneal exudate cells (PEC) of TLR4-deficient and wild-type mice after infection, but low levels of cytokines were produced in PEC of TLR2- and MyD88-deficient mice. On the other hand, high levels of IL-4 and IL-10 were produced in PEC of TLR2- and MyD88-deficient mice after infection, but low levels of cytokines were produced in PEC of TLR4-deficient and wild-type mice. The most remarkable histological changes with infiltration of inflammatory cells were observed in lungs of TLR2-deficient mice infected with T. gondii, where severe interstitial pneumonia occurred and abundant T. gondii were found.     

Histamine downregulates CD14 expression via H2 receptors on human monocytes

Lipopolysaccharide (LPS) binds to LPS-binding protein (LBP) in plasma and is delivered to the cell surface receptor CD14 on human monocyte. LPS is transferred to the transmembrane signaling receptor toll-like receptor (TLR) 4. In the present study, the effect of histamine on the expression of CD14 on human monocytes was investigated. Histamine concentration- and time-dependently decreased the expression of cell surface CD14, whereas histamine did not decrease mRNA for CD14 nor increase soluble CD14 (sCD14). The inhibitory effects of histamine on CD14 expression were antagonized by H2-receptor antagonist, but not by H1 and H3/H4 antagonist. The effects of selective H2-receptor agonists, 4-methylhistamine and dimaprit, on CD14 expression mimicked that of histamine indicating that histamine regulated CD14 expression through the stimulation of H2-receptors. The pretreatment with histamine partially inhibited the LPS-induced TNF-alpha production in human peripheral blood mononuclear cells (PBMC). Such inhibition might be due to the down-regulation of CD14 expression on monocytes by histamine.