Bacterial Mast cell conditioning modulates skin allergic reactions

 描述(由申请人提供)：我们的发现表明，肥大细胞(MC)在皮肤中可以有不同的细胞因子谱，皮肤微生物群对塑造这些不同的谱有很大影响。我们已经证明，皮肤表面的细菌产品可以诱导人类MCs的抗炎表型，有助于维持皮肤的动态平衡，并有助于避免不必要的炎症。在这项建议中，我们的目的是证明，在皮肤微生物组产品的调节下，MC可以在与人体免疫系统相关的环境中塑造皮肤对变应原的反应。利用体内和体外试验，我们打算确定MC-细菌相互作用在引导树突状细胞和T细胞转运对变应原的反应中的相对贡献。在我们的初步研究中，我们 使用来自两个代表性细菌株的成分：病原体金黄色葡萄球菌群落获得的耐甲氧西林美国300(美国300)和共生的表皮葡萄球菌，并表明它们都有能力改变MC炎症表型。我们将使用这些细菌成分来探索在过敏反应过程中操纵MC的可能性，最终目标是开发治疗过敏性炎症和相关皮肤病的新治疗策略。为了研究MC与细菌的相互作用在皮肤中的作用，我们提出如下建议：1.在活体内检测MC与细菌制品的预适应是否导致皮肤过敏反应的调节。我们推测，MC暴露于共生细菌小分子会诱导抗炎MC细胞因子谱，导致皮肤免疫环境的改变，降低皮肤的过敏反应。采用两种不同的小鼠过敏反应模型，研究MC预适应对皮肤过敏反应的影响。我们还将在体外系统中使用激光捕获显微解剖(LCM)来验证LTA和细菌产品对人皮肤MC IL-10表达的影响。体内过敏反应研究产生的数据将阐明MC产生的细胞因子的重要性，以及它们如何调节皮肤的过敏反应。2.探讨细菌制剂对体外培养的小鼠肾小球系膜细胞修饰树突状细胞细胞因子以调节变态反应的作用机制。我们推测，用共生副产物或LTA单独预适应MC，将阻止或减少树突状细胞(DC)的分化和T细胞的成熟，从而抑制过敏反应。在这项提案的第二部分，我们将把重点放在APC细胞因子上，它负责T细胞的极化。这项体外研究产生的数据将为我们提供关于预适应MC释放细胞因子如何扭曲过敏反应的机制的重要信息。

 DESCRIPTION (provided by applicant): Our findings suggest that Mast cells (MCs) can have different cytokine profiles in the skin and that the skin microbiome has a strong influence on shaping these different profiles. We have demonstrated that bacterial products at the skin surface induce an anti-inflammatory phenotype in human MCs that contributes to maintaining skin homeostasis and helps avoid unnecessary inflammation. In this proposal, we aim to demonstrate that MCs, conditioned by the skin microbiome products, can shape skin responses to allergens in contexts that are relevant to the human immune system. Using both in vivo and in vitro assays, we intend to define the relative contribution of MC-bacterial interactions in directing dendritic and T cell trafficking in response to allergens. In our preliminary studies, we employ components from two representative bacterial strains: the pathogen S. aureus community acquired methicillin resistant USA 300 (USA 300) and the commensal S. epidermidis and show that they are both capable of shifting MC inflammatory phenotypes. We will use these bacterial components to explore the possibility of manipulating MCs during allergic reactions with the end goal of developing new therapeutic strategies for the treatment of allergic inflammation and related skin diseases. To characterize of the effects of MC-bacterial interactions in the skin, we propose the followings: 1. To test whether preconditioning of MCs with bacterial products results in the modulation of skin allergic reactions in vivo. We hypothesize that exposure of MCs to commensal bacterial small molecules will induce anti-inflammatory MC cytokine profiles, resulting in changes to the skin immunological environment and the reduction of the allergic response in the skin. Using two different mouse models of allergic reaction we will investigate the effects of MC preconditioning on allergic reactions in th skin. We will also verify the effects of LTA and bacterial products on MC IL-10 expression in human skin using laser capture micro dissection (LCM) in an ex-vivo system. Data generated by the in vivo allergic reaction studies in this aim will clarify the importance of the cytokine profies generated by MCs and how they can modulate allergic reactions in the skin. 2. To investigate the mechanism of how preconditioning of MCs with bacterial products modifies dendritic cell cytokine profiles to modulate allergic reactions in vitro. We hypothesize that MCs preconditioned with commensal byproducts or LTA alone, will prevent or decrease dendritic cell (DC) differentiation and T cell maturation in vitro and consequently dampen the allergic response. In the second part of this proposal, we will focus our interest on APC cytokines, which are responsible for T cell polarization. Data generated by this in vitro study will give us important information regarding the mechanism of how the release of cytokines by preconditioned MCs can skew the allergic response.