Project 1: Role of Microbiota and Myeloid cells in Mouse Models of Barretts Esophagus

摘要 发达国家在过去30年中食管腺癌(EAC)的迅速增长有力地表明 环境影响。Barrett‘s食道(EAC)是EAC的前驱病变，其发病率正在增加，并与 食道微生物区系的改变。肥胖是EAC的另一个危险因素，与肠道微生物群的改变有关。 肠道细菌能够通过激活促进炎症和癌症的髓系细胞来促进炎症和癌症 再生和免疫抑制。在初步研究中，我们检查了L2中的微生物区系和髓系细胞 IL-1β小鼠BE模型。此小鼠模型显示12个月时GE连接微生物组的变化与 WT小鼠，并居住在无菌(GF)条件下可减少炎症、化生和异型增生。 在SPF条件下，喂食高脂饮食的L2-IL-1β小鼠表现出微生物群的变化和GE的增加 结合部肿瘤。用质子泵抑制剂(PPI)治疗也会加速GEJ的化生和异型增生。 这改变了胃微生物区系，并通过IL-8的表达，介导了髓系对微生物的反应。最后，我们有 开发的工具(HDC-EGFP和HDC-DTR小鼠)允许我们跟踪或去除未成熟的髓系细胞/MDSCs 对微生物做出反应，促进胃肠道肿瘤。我们提出了三个具体目标：(1)明确肠道的作用 使用L2-IL-1b小鼠模型研究BE/EAC中的微生物区系。疾病期间将对GE连接微生物区系进行分析 使用16S rRNA测序的进展，以及由GF外壳或抗生素抑制确定的EAC中的作用 通过有明确的植物区系的殖民。(2)肥胖和PPI是否部分通过微生物区系促进BE/EAC？我们会 通过HFD或PPI检查细菌根除对BE进展的影响。我们将研究微生物区系的变化 肥胖或苗条的患者。(3)。细菌是否主要通过髓系细胞诱导BE/EAC？我们将检查更改 在L2-IL-1β小鼠中髓系细胞对微生物群和IL-8的反应中，使用hDC-EGFP杂交，以及 通过消融和采用移植评估它们的功能作用。总而言之，这些研究将定义 微生物区系在BE/EAC进展中的潜在作用。

SUMMARY The rapid increase in developed countries over the past 30 years in esophageal adenocarcinoma (EAC) suggests strongly environmental influences. Barrett’s esophagus (EAC), a precursor lesion for EAC, is increasing and associated with alterations in esophageal microbiota. Obesity, another risk factor for EAC, is associated with an altered gut microbiome. Gut bacteria are able to promote inflammation and cancer through activation of myeloid cells that contribute to regeneration and immunosuppression. In preliminary studies, we have examined microbiota and myeloid cells in our L2- IL-1β mouse model of BE. This mouse model shows alterations in the GE junction microbiome at 12 months compared to WT mice, and housing in germ-free (GF) conditions leads to reductions in inflammation, metaplasia and dysplasia. Under SPF conditions, L2-IL-1β mice fed a high fat diet (HFD) show alterations in the microbiome and increased GE junction tumors. GEJ metaplasia and dysplasia are also accelerated by treatment with proton pump inhibitors (PPIs), which alters gastric microbiota, and by IL-8 expression, which mediates myeloid responses to microbes. Finally, we have developed tools (HDC-EGFP and HDC-DTR mice) that allow us to track or ablate immature myeloid cells/MDSCs that respond to microbes and promote gastrointestinal tumors. We propose 3 specific aims: (1) Define the role of gut microbiota in BE/EAC using the L2-IL-1b mouse model. The GE junction microbiota will be analyzed during disease progression using 16S rRNA sequencing, and the role in EAC determined by GF housing or antibiotic suppression, as well as by colonization with defined flora. (2) Do obesity and PPIs promote BE/EAC in part through microbiota? We will examine the effect of bacterial eradication on BE progression by HFD or PPIs. We will examine changes in microbiota in obese or slender BE patients. (3). Do bacteria induce BE/EAC primarily through myeloid cells? We will examine changes in myeloid cell trafficking to the GEJ in L2-IL-1β mice in response to microbiota and IL-8 using HDC-EGFP crosses, and assess their functional role through ablation and adoptive transfer. Taken together, these studies will define the potential role of microbiota in BE/EAC progression.