Regulating Cathelicidin Expression for Disease Therapy

描述（由申请人提供）：抗生素耐药菌感染和败血症的可能性是一个主要的健康问题。抗菌肽（AMP）如cathelicidins（CAMP）和防御素（defensins）作为潜在的杀微生物剂、抗LPS药物和炎症调节剂以及其他潜在用途在治疗用途上产生了相当大的兴趣。然而，CAMP表达的调控机制在很大程度上是未知的。驱动拟议研究的中心假设是来自CCAAT/增强子结合蛋白（C/EBP）、ETS/PU.1、CREB/ATF和类固醇/甲状腺激素受体家族的转录因子（TF）控制造血和上皮组织中CAMP的组成型和诱导型表达。我们提出了一项旨在实现3个特定目的的研究：[1]鉴定髓样和上皮细胞中调节CAMP基因转录的TF; [2a]确定维生素DS介导的CAMP诱导在各种人类细胞类型和特应性皮炎中的程度; [2b]鉴定类维生素A和维生素D3协同激活人类CAMP基因表达的机制; [2c]确定维生素D3对人类CAMP基因表达的影响。[2c]发现调节CAMP基因表达的新型小分子; [3]阐明维生素D3调节CAMP基因表达的生物学重要性和潜在治疗益处。具体目标1和2将产生对骨髓和上皮隔室中CAMP基因的转录调控的全面评估，并鉴定单独或与维生素D3组合可能证明治疗有用的其他化合物。具体目标3将表征维生素D对抗菌基因调控的进化和生物学重要性，并将使用平行的体外和体内小鼠模型，这些模型利用强大的遗传方法来严格检查维生素D3如何调节CAMP的表达，以应对微生物入侵或病原体衍生分子的挑战。这些具体目标的实现将提供一个全面的知识的CAMP基因的转录调控，并证明维生素D3介导的抗菌肽的调节的生物学重要性。这些知识将导致开发用于体外操纵内源性CAMP表达的方法，用于人类疾病的全身和局部治疗益处。

DESCRIPTION (provided by applicant): Infections by antibiotic resistant bacteria and the potential for sepsis are a major health concern. Antimicrobial peptides (AMPs) like cathelicidins (CAMP) and defensins are generating considerable interest for therapeutic use as potential bactericidals, anti-LPS drugs and modulators of inflammation, and other potential uses. However, the mechanisms governing CAMP expression are largely unknown. The central hypothesis driving the proposed research is that transcription factors (TFs) from the CCAAT/enhancer binding protein (C/EBP), ETS/PU.1, CREB/ATF and the steroid/thyroid hormone receptor families control constitutive and inducible expression of CAMP in hematopoietic and epithelial tissues. We propose an investigation directed towards achieving 3 Specific Aims: [1] Identify the TFs in myeloid and epithelial cells that regulate CAMP gene transcription; [2a] Determine extent of vitamin DS-mediated induction of CAMP in various human cell types and atopic dermatitis; [2b] Identify mechanism of synergistic activation of human CAMP gene expression by retinoids and vitamin D3; [2c] Discover novel small molecules that regulate CAMP gene expression; [3] Elucidate the biological importance and potential therapeutic benefits of vitamin D3 regulation of CAMP gene expression. Specific Aims 1 and 2 will generate a comprehensive assessment of the transcriptional regulation of the CAMP gene in the myeloid and epithelial compartments and identify additional compounds that either alone or in combination with vitamin D3 may prove therapeutically useful. Specific Aim 3 will characterize the evolutionary and biological importance of antimicrobial gene regulation by vitamin D and will use parallel in vitro and in vivo mouse models that exploit a powerful genetic approach to critically examine how vitamin D3 regulates expression of CAMP in response to microbial invasion or challenge with pathogen-derived molecules. Achievement of these specific aims will provide a comprehensive knowledge of the transcriptional regulation of the CAMP gene and demonstrate the biological importance of vitamin D3-mediated regulation of antimicrobial peptides. This knowledge will lead to the development of approaches for extrinsically manipulating endogenous CAMP expression for systemic and localized therapeutic benefit of human diseases.