Role of mouse microbiome in cancer and inflammation

在癌症免疫生物学部分以及癌症和炎症项目的其他一些部分以及CCR的其他部分中，非常需要了解肠道植物群在炎症和免疫性结肠炎发病机制中以及结肠炎相关癌症小鼠模型中的作用。我们广泛使用免疫或炎症相关基因缺陷的小鼠，并且总是难以区分这些基因对结肠炎或癌症的直接影响，或通过肠道植物群的调节的间接影响。该计划中的其他合作研究旨在研究肝脏免疫反应在控制肝癌发生中的作用，并且肝脏中的炎症免疫微环境也可能受到肠道植物群组成的显著影响。总体而言，这些研究将大大受益于无菌设施的使用，特别是基于最新测序和生物信息学的肠道微生物学专业知识的可用性，这些专业知识很难进入单个实验室，但可以有效地提供给在该领域具有重叠利益的多学科扩展实验室联盟。我们已经建立了使用16种RNA的454测序、特定细菌类型的FISH标记的细胞荧光分析以及可能的其他方法（包括微阵列）来确定小鼠微生物瘤的方法。将需要测序和生物信息学专业知识。我们还开始了无菌小鼠、具有明确肠道植物群的无菌小鼠和抗生素治疗后重建的小鼠的研究。最初，我们计划研究肠道植物群在结肠炎和结肠炎相关癌症的实验模型中的作用，使用遗传缺陷的炎症控制基因，如MyD 88，IL-18，TNF，TLR等。在小鼠实验模型和观察性临床实验中，正在计划肠道微生物群在与癌症相关的能量改变（即肥胖症、恶病质、厌食症）中的作用。居民皮肤免疫的分区控制（科学。2012;337：1115-9）。肠道细菌诱导保护性和调节性反应，维持宿主-微生物互惠共生。然而，在其他屏障部位，组织驻留的细胞对免疫和炎症的贡献尚未得到解决。我们发现，在小鼠中，皮肤微生物群在控制局部炎症环境和调节常驻T淋巴细胞功能方面具有自主作用。对皮肤病原体的保护性免疫被发现严重依赖于皮肤微生物群，而不是肠道微生物群。此外，皮肤细胞以依赖于白细胞介素-1受体下游信号传导的方式调节局部T细胞的功能。这些发现强调了微生物群作为组织区室化的独特特征的重要性，并提供了对健康和疾病中居民肠道小生境的免疫系统调节机制的见解。共生细菌通过调节肿瘤微环境来控制癌症对治疗的反应（Science 342：967-970）。肠道微生物组影响局部和全身炎症。尽管炎症在癌症中的作用已被充分证明，但肠道细菌是否能对无菌肿瘤微环境中的炎症产生远距离影响仍不清楚。在这里，我们表明微生物群扰动损害皮下癌对CpG寡核苷酸免疫疗法或铂化疗的反应。在化疗或无菌小鼠中，CpG-ODN治疗后肿瘤浸润单核细胞衍生细胞的细胞因子产生减少，肿瘤坏死减少，而缺乏化疗诱导的骨髓细胞产生的活性氧损害了遗传毒性和肿瘤破坏。因此，对癌症免疫疗法和化学疗法的最佳反应需要完整的肠道微生物群，其通过调节肿瘤微环境中的髓源性细胞功能而远距离发挥作用。这些发现强调了微生物群在疾病治疗结果中的重要性。

In the Section of Cancer Immmunobiology as well as in a few other Sections within the Cancer and Inflammation Program as well as other part of CCR there is great need to understand the role of the gut flora in the pathogenesis of inflammatory and immune colitis and in mouse models of colitis-associated cancer. We extensively use mice deficient for immune or inflammation-related genes and it is always difficult to distinguish a direct effect of those genes on the colitis or cancer, or an indirect one through the regulation of the intestinal flora. Other collaborative studies in the program are directed to the study of the role of the liver immune response in controlling liver carcinogenesis and it is likely that the inflammatory-immunological microenvironment in the liver is also significantly affected by the composition of the intestinal flora. Overall these studies would greatly benefit by the access to a germ free facility and particularly by the availability of committed expertise in gut microbiology based on state of the art sequencing and bioinformatics, expertise that it is of difficult access to single laboratories but that could be efficiently provided to a multidisciplinary extended consortium of laboratories with overlapping interests in this field. We have established methods for the determination of mouse microbioma using 454 sequencing of 16 RNA, cytofluorimetric analysis of FISH labeling of specific bacterial types, and possibly other approaches including microarray. Sequencing and bioinformatic expertise will be needed. We also initiated studies with germ free mice, gnotobiotic mice with defined intestinal flora, and mice reconstitute after antibiotic treatment. Initially we plan to study the role of the intestinal flora in experimental models of colitis and colitis-associated cancer using mice genetically deficient for inflammation-controlling genes such as MyD88, IL-18, TNF, TLRs, and others. The role of commensal microbiota in energetic alteration associated with cancer (i.e. obesiti, cachxia, anorexia) is being planned in murine experimental models and in observational clinical experimentation. Compartmentalized control of skin immunity by resident commensals (Science. 2012;337:1115-9). Intestinal commensal bacteria induce protective and regulatory responses that maintain host-microbial mutualism. However, the contribution of tissue-resident commensals to immunity and inflammation at other barrier sites has not been addressed. We found that in mice, the skin microbiota have an autonomous role in controlling the local inflammatory milieu and tuning resident T lymphocyte function. Protective immunity to a cutaneous pathogen was found to be critically dependent on the skin microbiota but not the gut microbiota. Furthermore, skin commensals tuned the function of local T cells in a manner dependent on signaling downstream of the interleukin-1 receptor. These findings underscore the importance of the microbiota as a distinctive feature of tissue compartmentalization, and provide insight into mechanisms of immune system regulation by resident commensal niches in health and disease. Commensal bacteria control cancer response to therapy by modulating the tumor microenvironment (Science 342:967-970). The gut microbiome influences both local and systemic inflammation. Although the role of inflammation in cancer is well documented, whether commensal bacteria can exert distant effects on the inflammation in the sterile tumor microenvironment remains unclear. Here we show that microbiota perturbation impairs the response of subcutaneous cancers to CpG-oligonucleotide-immunotherapy or platinum chemotherapy. In antibiotic-treated or germ-free mice, decreased cytokine production from tumor-infiltrating monocyte-derived cells following CpG-ODN treatment reduced tumor necrosis, whereas deficient chemotherapy-induced production of reactive oxygen species by myeloid cells impaired genotoxicity and tumor destruction. Thus, optimal response to cancer immunotherapy and chemotherapy requires an intact commensal microbiota that acts distantly by modulating myeloid-derived cell function in the tumor microenvironment. These findings underscore the importance of the microbiota in the outcome of disease treatment.