Impaired Tumor-Necrosis-Factor-α-driven Dendritic Cell Activation Limits Lipopolysaccharide-Induced Protection from Allergic Inflammation in Infants

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Enhanced Platelet Activation in Patients with Atopic Eczema/Dermatitis Syndrome

Data gathered prove that circulating platelets are activated upon human allergic inflammation, partly as a result of direct IgE-mediated process. It has been indicated that platelets may contribute to pathogenesis of atopic eczema/dermatitis syndrome (AEDS). Authors of the recent study have investigated systemic platelet activation in patients with AEDS on the basis of blood level of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4), which are recognized markers of platelet activation, also belonging to C-X-C chemokine family. Plasma levels of beta-TG and PF4 were measured by enzyme-linked immunoassay (ELISA) in 18 AEDS patients with moderate disease activity and 23 healthy, nonatopic individuals. No differences in peripheral platelet count of the two groups were noted. Only four (33.3%) AEDS patients represented beta-TG and PF4 within the control range; plasma beta-TG and PF4 were significantly increased (p < 0.001) in the AEDS group compared as a whole with the control subjects. No association between circulating concentrations of beta-TG or PF4 and total IgE levels in AEDS patients was proved. The results suggest that some patients with AEDS may have enhanced blood platelet activity as expressed by beta-TG and PF4 level.     

Platelet Function Analyzer: Shear Activation of Platelets in Microchannels

Platelet function is suggestive of pathological conditions in cardiovascular diseases. With current insufficient prognostic devices, the need exists for a device to assess complete platelet function. This work presents a preliminary microfluidic device for such analysis based on platelet adhesion under shear flow conditions. In this novel device, polydimethylsiloxane (PDMS) microchannels were coated using a layer-by-layer self-assembly technique to provide controlled nanometer-thick layers of fibrinogen. Anticoagulated platelet rich plasma labeled with a fluorescein isothiocynate-tagged anti-glycoprotein IIb/IIIa-antibody and acridine orange was passed through these micro-channels at various time-averaged shear rate values. Fluorescence assays confirmed shear-dependent adhesion of platelets in the microchannels. Control experiments showed that the extent of adhesion on bare PDMS surfaces was less than on the surfaces coated with fibrinogen at similar shear rates. Fluorescent microscopy demonstrated that the extent of platelet adhesion to the fibrinogen substrate depended on shear rate. The extent of adhesion was modeled as a third order polynomial in shear rate.     

Role of Airway Eosinophilia and Eosinophil Activation in Sephadex-induced Inflammation

The effects of an intravenous injection of Sephadex beads on lung eosinophil infiltration and eosinophil peroxydase activity and its relationship to bronchial hyperresponsiveness was examined in guinea pigs. This Sephadex beads injection led to blood, lung and airway eosinophilia in association with bronchial hyperresponsiveness. Histologic examination of the lower bronchus indicated that the eosinophil number increased markedly in the mucosa and submucosa. In addition, the eosinophils surrounding the bronchioles 1 day after the Sephadex injection migrated further in airway submucosa and mucosa 7 and 14 days after. Moreover, the bronchial hyperresponsiveness is observed without histologic evidence of airway epithelium damage. Therefore, the bronchial hyperresponsiveness seems to be more related to the eosinophil infiltration in the airway epithelium and possibly eosinophil activation rather than to the eosinophil number recovered in the BAL fluid. We conclude that the maintenance of hyperresponsiveness state could be associated with the persistence of blood and airway eosinophilia.     

Platelet activation factor inhibits irritant-induced migration of leukocytes into the mouse peritoneal cavity

Institute of Cell Biochemistry and Physiology, Biotechnology Center, Ministry of Health of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 5, pp. 481–483, May, 1991,     

三色流式细胞术检测全血中血小板活化

三色流式细胞术检测全血中活化血小板P 选择素的表达。采用双注射器筒采外周静脉血 ,枸橼酸钠抗凝。取 5 μl全血 ,加入 5 μlCD42a FITC、 5 μl6 2P PE、 5 μlCD45 CY ,室温避光 2 0min ,1%多聚甲醛固定 10min ,PBS洗后 ,上机分析。结果显示 ,全血三色法测定全血中血小板P 选择素表达阳性率明显低于富血小板血浆 (P <0 0 5 )。全血三色法测定全血中血小板P 选择素表达客观、特异、更接近人体生理情况。     

Mechanism of Activation of ADP-Induced Platelet Aggregation under the Influence of Oxidatively Modified Fibrinogen

For evaluation of the mechanisms underlying the effect of oxidized fibrinogen on platelet aggregation we studied ADP-induced platelet aggregation in the presence of UV-oxidized fibrinogen and inhibitors of major enzymes of platelet activation. Cyclooxygenase inhibitor acetylsalicylic acid, protein kinase C inhibitor H7, and to a lesser extent, protein tyrosine kinase inhibitor genistein suppressed ADP-induced platelet aggregation. In the presence of oxidized fibrinogen the degree of suppression was lower than in the presence of nonoxidized fibrinogen. Phospholipase C inhibitor U73122 markedly suppressed platelet aggregation in the presence of oxidized and nonoxidized fibrinogen. It can be hypothesized that oxidized fibrinogen activates platelets by modulating activity of the key signal component phospholipase C.     

Two-Dimensional Dynamic Simulation of Platelet Activation During Mechanical Heart Valve Closure

A major drawback in the operation of mechanical heart valve prostheses is thrombus formation in the near valve region. Detailed flow analysis in this region during the valve closure phase is of interest in understanding the relationship between shear stress and platelet activation. A fixed-grid Cartesian mesh flow solver is used to simulate the blood flow through a bi-leaflet mechanical valve employing a two-dimensional geometry of the leaflet with a pivot point representing the hinge region. A local mesh refinement algorithm allows efficient and fast flow computations with mesh adaptation based on the gradients of the flow field in the leaflet-housing gap at the instant of valve closure. Leaflet motion is calculated dynamically based on the fluid forces acting on it employing a fluid-structure interaction algorithm. Platelets are modeled and tracked as point particles by a Lagrangian particle tracking method which incorporates the hemodynamic forces on the particles. A platelet activation model is included to predict regions which are prone to platelet activation. Closure time of the leaflet is validated against experimental studies. Results show that the orientation of the jet flow through the gap between the housing and the leaflet causes the boundary layer from the valve housing to be drawn in by the shear layer separating from the leaflet. The interaction between the separating shear layers is seen to cause a region of intensely rotating flow with high shear stress and high residence time of particles leading to high likelihood of platelet activation in that region.     

白介素17单克隆抗体对变应性鼻炎小鼠气道炎症的作用

目的 探讨白介素17单克隆抗体（IL-17mAb）的不同给予剂量及方式在变应性鼻炎小鼠气道炎症中的作用。方法 将48只小鼠采用随机数字表法分为A、 B、 C、 D、 E、 F组,每组8只。分别于第0、 7、 14 d将20 μg卵清蛋白（OVA）加2 mg铝佐剂腹腔注射处理A、C、D、E及F组小鼠,间隔7 d,第22天开始进行鼻腔激发,每天每侧鼻孔各给予OVA 10 μl（共500 μg）滴鼻,连续7 d。A、C、D、E组小鼠于每次OVA鼻腔激发前1 h分别给予生理盐水、100 ng IL-17mAb、500 ng IL-17mAb、5 μg IL-17mAb滴鼻,F组小鼠于每次OVA鼻腔激发前4 h给予5 μg IL-17mAb腹腔注射,B组小鼠于相同时间点给予等量生理盐水腹腔注射及滴鼻。所有小鼠于最后1次激发后评估鼻部症状学变化,Diff-Quik染色观察鼻腔灌洗液（NLF）中嗜酸性粒细胞浸润情况,ELISA方法检测血清及NLF中IL-6、IL-10水平,鼻黏膜组织行甲苯胺蓝染色观察肥大细胞。结果 ４周末A组所有小鼠症状学评分均＞5分,提示造模成功。F组小鼠的挠鼻及喷嚏次数均少于A组（P＜0.05）;F组小鼠NLF中嗜酸性粒细胞数、血清IL-6水平低于A组,血清及NLF中IL-10水平均高于A组（P＜0.05）;E组小鼠血清中IL-10水平高于A组（P＜0.05）;A组小鼠鼻黏膜组织中肥大细胞数多于B组,统计学意义显著（P＜0.01）;F组小鼠鼻黏膜组织中肥大细胞数少于A组,但差异无统计学意义（P＞0.05）;F组小鼠鼻黏膜组织中肥大细胞数与B组比较,差异无统计学意义（P＞0.05）。结论 高剂量的（5 μg）IL-17mAb腹腔注射处于激发阶段的变应性鼻炎小鼠促使小鼠变应性鼻炎症状明显减轻,鼻腔灌洗液嗜酸性粒细胞减少。促使变应性鼻炎小鼠血清中IL-6表达降低,血清中及鼻腔灌洗液中IL-10表达升高,因此推测这些细胞因子的变化可能抑制Th17/促进Treg的分化,进而对变态反应产生抑制作用。     

Calcineurin Aα Contributes to IgE-Dependent Mast-Cell Mediator Secretion in Allergic Inflammation

Mast cells (MCs) are key mediators of allergic inflammation through the activation of cross-linked immunoglobulin E (IgE) bound to the high-affinity IgE receptor (FcϵRI) on the cell surface, leading to the release of biologically potent mediators, either from preformed granules or newly synthesized. Pharmacological inhibitors have been developed to target a key signaling protein phosphatase in this pathway, calcineurin, yet there is a lack of genetic and definitive evidence for the various isoforms of calcineurin subunits in FcϵRI-mediated responses. In this study, we hypothesized that deficiency in the calcineurin Aα isoform will result in a decreased allergic immune response by the MCs. In a model of passive cutaneous anaphylaxis, there was a reduction in vascular permeability in MC-deficient mouse tissues reconstituted with calcineurin subunit A (CnAα) gene-knockout (CnAα^−/−) MCs, and in vitro experiments identified a significant reduction in release of preformed mediators from granules. Furthermore, released levels of de novo synthesized cytokines were reduced upon FcϵRI activation of CnAα^−/− MCs in vitro. Characterizing the mechanisms associated with this deficit response, we found a significant impairment of nuclear factor of kappa light polypeptide gene enhancer in B cell phosphorylation and impaired nuclear factor kappa-light-chain-enhancer of activated B-cell inhibitor alpha (NF-κB) activation. Thus, we concluded that CnAα contributes to the release of preformed mediators and newly synthesized mediators from FcϵRI-mediated activation of MCs, and this regulation includes NF-κB signaling.     

Sigma-1 Receptor Expression in DRG Neurons During a Carrageenan-Provoked Inflammation

Sigma 1 receptor (σ1R) is a non-opioid receptor that modulates pain perception and is strongly expressed in dorsal root ganglion (DRG) neurons. We studied the changes in the expression of σ1R in different sub-populations of DRG neurons during the first 48 hr in a carrageenan-induced inflammation rat model, with σ1R being a possible base for the development of neuropathic pain after inflammation. Twenty Sprague Dawley rats were divided into five groups (N = 4 in each group): the control (C) group was sacrificed immediately; all other animals received an intraplantar injection of 0.1 mL 2% carrageenan and were sacrificed in 6, 12, 24 or 48 hr after the injection and DRGs were collected and processed for immunohistochemistry. σ1R fluorescence intensity decreased slightly but significantly in up to 24 hr post-carrageenan injection in all sub-populations of DRG neurons (ib4+; ib4− medium, ib4− large and ib4− in total; P < 0.05 – P < 0.001), with the exception of the ib4− small neurons (<25 μm; P > 0.05). This decrement was followed by a subsequent increase in σ1R fluorescence intensity 48 hr after the plantar carrageenan injection (P < 0.05 – P < 0.0001). The same trend was also observed in the CGRP+ population of the DRG neurons, in the total population as well as in the CGRP+ small (<25 μm) and larger CGRP (>25 μm) sub-populations (P < 0.05 – P < 0.001). The presented results may contribute to further understanding of role of σ1R in the development of peripheral sensitization during inflammation. They may also be valuable for the therapeutic application of σ1R antagonists, particularly in the adjustment of the antagonist's dosage in a particular time window. Anat Rec, 302:1620–1627, 2019. © 2019 American Association for Anatomy     

Enhanced Allergic Inflammation of Der p 2 Affected by Polymorphisms of MD-2 Promoter

Purpose

Myeloid differentiation-2 (MD-2) has been associated with endotoxin and inflammatory disorders because it can recognize lipopolysaccharide (LPS) binding and attenuate Toll-like receptor 4 (TLR4)-mediated signaling. However, its role in allergic inflammation has yet to be clarified. We examined whether single nucleotide polymorphisms (SNPs) in MD-2 promoter can affect MD-2 expression and aimed to clarify the relationship between Der p 2 allergy and SNPs of MD-2 promoter.

Methods

The function of SNPs of MD-2 promoter and the effects of cytokines and immunoglobulin on the secretion and mRNA expression were investigated in 73 allergic subjects with different MD-2 gene promoter variants. Peripheral blood mononuclear cells were cultured with or without LPS in the presence of Dermatophagoides pteronyssinus group 2 allergen (Der p 2), followed by mRNA extraction and cytokine expression analysis. The culture supernatants were collected for cytokine measurement.

Results

Patients with the MD-2 promoter SNPs (rs1809441/rs1809442) had increased mRNA expressions of MD-2, ε heavy chain of IgE (Cε), and interleukin (IL)-8; however, only MD-2 and IL-8 were further up-regulated after Der p 2 stimulation. Patients with SNPs of MD-2 promoter tended to have high levels of IL-1β, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α after Der p 2 and LPS stimulation. Increased secretions of IL-6, IL-8, and IL-10 were found to be up-regulated by Der p 2 stimulation, and an increased secretion of IFN-γ and decreased secretion of IL-4 were noted after LPS stimulation.

Conclusions

The high levels of proinflammatory cytokines secreted by Der p 2 were predetermined by MD-2 promoter SNPs (rs1809441/rs1809442). Through cytokine secretion by Der p 2 and LPS, these SNPs may serve as an indicator of the pathological phenotype of Der p 2-induced allergic inflammation.     

Platelet activating factor and endotoxin-induced platelet activation

Central Research Institute of Epidemiology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. I. Pokrovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 5, pp. 538–540, May, 1989.     

The Allergic Airway Inflammation Repository – a user‐friendly,curated resource of mRNA expression levels in studies of allergic airways

Public microarray databases allow analysis of expression levels of candidate genes in different contexts. However, finding relevant microarray data is complicated by the large number of available studies. We have compiled a user‐friendly, open‐access database of mRNA microarray experiments relevant to allergic airway inflammation, the Allergic Airway Inflammation Repository (AAIR, http://aair.cimed.ike.liu.se/ ). The aim is to allow allergy researchers to determine the expression profile of their genes of interest in multiple clinical data sets and several experimental systems quickly and intuitively. AAIR also provides quick links to other relevant information such as experimental protocols, related literature and raw data files.     

Effect of Stress Due to Anticipated Minor Surgery upon in Vivo Platelet Aggregation in Humans

Abstract

When measured just prior to hospital admission, platelet aggregation was faster and systolic and diastolic blood pressure were higher compared to measurements just prior to surgery and upon discharge from the hospital.     

精—甘—天冬—丝氨酸肽抑制血小板活化的胞内信号转导机制

本工作在凝血酶活化的大鼠血小板上,观察ＲＧＤＳ肽对血小板聚集,蛋白磷酸化及丝裂素活化蛋白激酶（ＭＡＰＫ）活性的影响,结果发现,ＩＵ／ｍＬ凝血酶明显引起血小板聚集,９５和６６ｋＤ蛋白磷酸化及ＭＡＰＫ活性的增加,应用５０、１００、２００μｍｏｌ／ＬＲＧＤＳ肽共向孵育,呈浓度依赖地抑制凝血酶引起的血小板聚集和ＭＡＰＫ活性,且两者呈正相关（ｒ＝０．８１,Ｐ＜０．０１）。ＲＧＤＳ肽亦呈浓度依赖地抑制凝血酶诱导的９５和６６ＫＤ蛋白磷酸化,与其抑制ＭＡＰＫ活性呈明显正相关（ｒ＝０．４１,Ｐ＜０．０５和ｄ．５３,Ｐ＜０．０１）。提示,ＭＡＰＫ系统参与了凝血酶引起的Ｗ小板聚集,ＲＧＤＳ肽抑制血小板聚集机理之一可能是通过干预血小板内信号传导途径所致。     

Platelet antigens in dogs

Four antigens specific for platelets and unconnected with antigens of red and white blood cells, were distinguished in dogs by the thromboagglutination test. Inheritance of platelet antigens in dogs is Mendelian in type and is controlled by several recessive genes.Laboratory of Experimental Surgery, A. V. Vishnevskii Institute of Surgery, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Savel'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 12, pp. 1455–1457, December, 1976.