Expression and function of microRNA in autoimmune Sjogren's Syndrome

描述（由申请人提供）：自身免疫性Sj" green 's syndrome （SjS）主要以女性个体的外分泌腺（如唾液腺和泪腺）为靶点，导致严重的分泌功能障碍及其并发症。由于SjS发病机制的复杂性，迄今为止，SjS特异性的诊断和治疗还没有可用。MicroRNAs （miRNAs）是一类重要的非编码rna，参与多种生物、病理和免疫过程。我们最新的研究结果表明，与健康对照相比，原发性SjS患者外周血单核细胞（PBMC）或单核细胞中miR-146a和- 155表达的改变表明，mirna可能在SjS的自身免疫启动和进展中发挥关键作用。易患pjs的C57BL/6的唾液腺和PBMC的研究结果进一步支持了这一数据。NOD-Aec1Aec2小鼠模型，其中从早期开始观察到这些mirna的上调。在我们的初步体外研究中，人单核细胞系（THP-1）中miR-146a的过表达能够改变先天免疫反应，如吞噬和促炎细胞因子的产生。我们现在提出的研究旨在验证我们的假设，即miR-146a和miR-155通过改变先天免疫反应对延长炎症过程至关重要，特别是参与先天免疫的psjs特异性mirna可以差异表达（甚至可能在疾病发作之前导致持续炎症）。在本项目的目的1中，我们将利用miRNA模拟物和抑制剂转染THP-1细胞，然后进行功能测定，研究miR-146a和/或miR-155改变的后果。改变的功能也将在pSjS患者的原代培养单核细胞中进行测试。目的是确定mirna对免疫基因的表观遗传调控是否在SjS中改变免疫过程中起关键作用。在目标2中，我们将利用miRNA微阵列方法开始分析与psi有关的复杂miRNA网络。在这里，我们将验证我们的假设，即人类psj特异性的miRNA谱是可识别的。此外，我们将继续在Aim 2中鉴定差异表达mirna的靶基因，并进行Aim 1中建立的功能测定，以筛选它们参与先天免疫反应。我们设想，这些实验将鉴定出psj中的新型mirna，以及鉴定出的mirna在SjS异常免疫调节中的调节功能，并可能最终适用于生物标志物和治疗干预的开发。

DESCRIPTION (provided by applicant): Autoimmune Sj"gren's syndrome (SjS) targets the exocrine glands, such as the salivary and lacrimal glands, of mostly female individuals, leading to severe secretory dysfunction and its complications. To date, SjS- specific diagnostics and therapeutics have not been available due to complexity of SjS disease pathogenesis. MicroRNAs (miRNAs) have been recognized as an important class of non-coding RNAs that are involved in a variety of biological, pathological, and immunological processes. Our latest findings on altered miR-146a and- 155 expression in peripheral blood mononuclear cells (PBMC) or monocytes of primary SjS (pSjS) patients in comparison with healthy controls indicate that miRNAs may play a critical role in autoimmune initiation and progression of SjS. The data were further supported by the findings in the salivary glands and PBMC of our pSjS-prone C57BL/6.NOD-Aec1Aec2 mouse model, where up-regulation of those miRNAs was observed from an early age on. Over-expression of miR-146a in human monocyte cell line (THP-1) was able to alter innate immune responses such as phagocytosis and pro-inflammatory cytokine production in our preliminary study in vitro. We now propose studies designed to test our hypotheses that miR-146a and miR-155 are vital to prolong inflammatory processes by altering innate immune response and that pSjS-specific miRNAs especially involved in innate immunity can be differentially expressed (potentially even prior to disease onset resulting in persistent inflammation). In Aim 1 of this project, we will investigate consequences of altered miR-146a and/or miR-155 by utilizing miRNA mimics and inhibitors transfected into THP-1 cells followed by functional assays. Altered functions will also be tested in primary cultured monocytes from pSjS patients. This aim is to determine if epigenetic regulation of immune genes by miRNAs are critical in altering immunological processes in SjS. In Aim 2, we will begin to profile a complex network of miRNAs involved in pSiS by utilizing a miRNA microarray approach. Here we will test our hypothesis that miRNA profiles that are specific for human pSjS are identifiable. Furthermore, we will continue to identify in Aim 2 target genes of differentially expressed miRNAs and perform functional assays established in Aim 1 to screen their involvement in innate immune responses. We envision that these experiments will identify novel miRNAs in pSjS and regulatory functions of identified miRNAs in abnormal immune regulation of SjS and may ultimately be amenable to development of biomarkers and therapeutic intervention.