Components of distinct rural environments confer asthma protection in childhood via A20-mediated immune effects in dendritic cells on regulatory T cells

该项目旨在通过环境不同区域的化合物刺激血细胞，解开树突状细胞（DC）和调节性T细胞（TCFs）对儿童哮喘的A20介导作用的不同保护性免疫调节机制。独特的自然暴露于两种环境，即欧洲的农场和中国的农村地区，强烈保护儿童哮喘，这为评估彼此不同的潜在免疫机制提供了很好的机会。由于A20（抗炎）和炎性体调节在不同的粉尘刺激后表现出差异表达，我们将鉴定A20和炎性体调节在细胞系和分离的细胞中暴露于不同粉尘的环境后的特定作用。我们将解开特定的哮喘保护性免疫机制，通过A20介导的影响，通过暴露于不同的农村环境灰尘的健康和哮喘儿童的树突状细胞对TcB。我们将揭示来自不同环境地区（德国、芬兰、中国）的环境粉尘提取物对T reg功能、甲基化、乙酰化（FOXP 3启动子）和mTOR信号传导的影响。我们的目的是确定A20在DC和炎症体激活中的调节信号。我们的目的是研究树突状细胞中A20调节和炎性小体激活对Treg介导的抑制的影响。最后，在原理验证实验中，我们将评估灰尘刺激对与哮喘儿童相比的哮喘儿童中的DC、炎性小体和Treg调节中的A20调节的影响。微生物细菌的不同代谢产物，如短链脂肪酸（SCFA），已被证明对Treg功能至关重要，可防止鼠结肠炎，并可能防止鼠过敏性气道炎症。因此，我们的目标是确定SCFA（和不同环境区域的灰尘的其他代谢物）对A20介导的DC-Treg轴的调节和炎症小体调节的哮喘保护作用。为了确定相关成分，我们将检查不同粉尘中SCFA和代谢物的含量。我们的目的是研究SCFA对受保护和哮喘儿童体外DC和Treg反应的影响。我们现在处于独特的位置：i）有足够数量和质量的来自不同农村环境的灰尘，ii）比较不同队列中有哮喘风险和受保护的儿童，以全面评估A20介导的DC-Treg机制，用于随后的儿童哮喘一级/二级预防策略。该项目不仅将提供对哮喘保护相关因素的深入途径分析，而且还提供了一个无与伦比的机会，可以在环境非常不同的地区（欧洲/中国）解开不同或共同的途径，这对于转化为未来的儿童哮喘预防策略至关重要。

This project aims to disentangle distinct protective immune regulatory mechanisms of A20-mediated effects of dendritic (DC) and regulatory T cells (Tregs) for childhood asthma by stimulation of blood cells with compounds of environmentally distinct areas. The unique natural exposure to two environments strongly protecting from childhood asthma, i.e. farms in Europe and rural areas in China offers the great opportunity to assess underlying immune mechanisms which are distinct from each other. As A20 (anti-inflammatory) and inflammasome regulation have been shown differentially expressed following different dust stimulation, we will identify the specific role of A20 and inflammasome regulation following environmental exposure with different dusts in cell lines, and isolated cells. We will disentangle specific asthma-protective immune mechanisms via A20-mediated effects of DCs on Tregs through exposure to distinct rural environmental dust in healthy and asthmatic children. We will unravel the effect of environmental dust extracts from different environmental areas (Germany, Finland, China) on T reg-function, methylation, acetylation (FOXP3 promoter), and mTOR signalling. We aim to identify signalling of A20 regulation in DCs and inflammasome activation. We aim to investigate the effect of A20-regulation in DCs and inflammasome activation on Treg-mediated suppression. Finally, in a proof-of-principle experiment, we will assess the effects of dust stimulation on A20-regulation in DCs, inflammasome and Treg regulation in children protected from asthma in comparison to asthmatic children. Different metabolites of microbial bacteria such as short-chain fatty acids (SCFA) have been shown critical for Treg-function protecting against murine colitis, and possibly murine allergic airway inflammation. Thus, we aim to identify the effect of SCFA (and other metabolites of dust of distinct environmental areas) on the regulation of the A20-mediated DC-Treg-axis and inflammasome regulation for asthma protection. To pin-point the relevant components, we will examine the content of SCFA and metabolites present in the different dusts. We aim to investigate the effects of SCFA on DC and Treg-responses in vitro in protected and asthmatic children. We are now in the unique position of i) having the dusts from distinct rural environments available in sufficient amount and quality, ii) having a comparison of children at risk and protected from asthma in different cohorts available to comprehensively assess A20-mediated DC-Treg mechanisms for subsequent strategies for primary/secondary prevention of childhood asthma. This project will not only provide in depth pathway analysis of relevant factors for asthma protection, but represents an unparalleled opportunity to disentangle different or common pathways in environmentally very distinct areas (Europe/China), which is critical for the translation into future prevention strategies for childhood asthma.