Genetic and hormonal mechanisms mediating sex differences in TB and TB-HIV

项目摘要 结核病（TB）在男性（约70%的病例）中比女性更常见。虽然获得护理的机会减少， 对女性和女性病例的低估可能会对这种长期流行病有一定的影响。 在一些国家的观察，无论是人类研究（吕贝克灾难和太监研究）以及动物 这些模型强调了生物因素在女性对结核病的耐药性中起主导作用的事实。尽管 尽管结核病中这种性别偏见的重要性，但它在很大程度上被基础科学研究人员所忽视。中央 这种应用的科学前提是，确定结核病男性偏好的生物学机制， 启发我们对结核病发病机制和结核病中保护性人类免疫应答的机制理解。一 一个多学科团队，在性别差异（Klein）、结核病发病机制（Bishai）和性别方面拥有数十年的专业知识 艾滋病毒的差异（斯卡利）将进行该项目。 这项提案将调查遗传学（X染色体互补）和性类固醇激素的影响 使用细胞工具、动物模型和人体样本研究结核病发病机制。目标1中使用的一个关键工具是 新的四核心基因型（FCG）小鼠模型，其中具有XX基因型的动物具有雄性 具有XY基因型的人具有雌性性腺/激素水平，而具有XY基因型的人具有雌性性腺/激素水平。这种模式的 使我们能够区分遗传学和性类固醇对小鼠结核病控制的影响。 X染色体编码许多具有免疫学重要性的基因，包括编码 TLR 7、TLR 8、CYBB、NEMO、CD 40 L和FOXP 3。X染色体失活（XCI）的过程， 一个女性X染色体是表观遗传沉默-旨在提供平衡的基因剂量之间 女性和男性。然而，某些基因可以逃脱XCI，导致女性的基因剂量加倍。的 尚未在结核病背景下研究XCI的基因逃逸过程，先进的分子工具将 在目标2中用于研究XCI基因逃逸作为结核病严重程度男性偏好的原因。 虽然众所周知性类固醇信号传导调节免疫功能，但性类固醇作为免疫调节剂的影响 结核病中男性偏见的基础尚未得到彻底调查。替吉奥具有免疫耐受作用， 降低IFN-γ水平和升高IL-4水平。相反，雌激素促进更高水平的巨噬细胞 激活和TNF-α水平升高。在目标2中，我们将仔细剖析性类固醇的作用， 转移方法以及用选择性激素替代的性腺切除小鼠。 最后，在目标3中，我们将扩展这些研究，以评估艾滋病毒感染（结核病的关键风险）与 免疫力的性别差异我们将评估艾滋病毒感染者（PLWH）样本的免疫反应。 ART与健康对照（HC），特别是性别平衡组。我们将评估整体的能力 来自PLWH和HC的血液和hMDM以单独和在DHEA存在下均包含Mtb生长。最后， 我们将评估Mtb感染后来自男性和女性PLWH和HC的PBMC中的转录组学应答。

PROJECT SUMMARY Tuberculosis (TB) occurs more frequently in males (~70% of cases) than females. While reduced access to care for females and undercounting of female cases may contribute modestly to this longstanding epidemiologic observation in some countries, both human studies (the Lűbeck disaster and eunuch studies) as well as animal models underscore the fact that biological factors play a dominant role in female resistance to TB. Despite the importance of this sex-bias in TB, it has gone largely neglected by basic science researchers. The central scientific premise of this application is that defining the biological mechanisms of the male bias for TB will enlighten our mechanistic understanding of TB pathogenesis and protective human immune responses in TB. A multidisciplinary team with decades of expertise on sex differences (Klein), TB pathogenesis (Bishai), and sex differences in HIV (Scully) will conduct the project. This proposal will investigate the impact of genetics (X chromosome complement) and sex steroid hormones on TB pathogenesis using cellular tools, animal models, and human samples. A key tool used in Aim 1 will be the novel four core genotype (FCG) mouse model, in which animals with XX genotypes have male gonads/hormone levels and those with XY genotypes have female gonads/hormone levels. This model will enable us to differentiate the impact of genetics from those of the sex steroids on murine control of TB. The X chromosome encodes numerous genes of immunologic importance including the genes that encode for TLR7, TLR8, CYBB, NEMO, CD40L, and FOXP3. The process of X-chromosome inactivation (XCI)--in which one female X chromosome is epigenetically silenced--is designed to provide balanced gene dosing between females and males. Certain genes, however, can escape XCI, leading to a double gene dose in females. The process of gene escape from XCI has not been studied in the context of TB, and advanced molecular tools will be used in Aim 2 to investigate gene escape from XCI as a cause of the male bias in severity of TB. While it is widely known that sex steroid signaling modulates immune function, the impact of sex steroids as a basis for the male bias in TB has not been thoroughly investigated. Testosterone has an immunotolerizing effect, reducing levels of IFN-γ and elevating levels of IL-4. In contrast, estrogen promotes higher levels of macrophage activation and increases in TNF-α levels. In Aim 2, we will carefully dissect the role of sex steroids using adoptive transfer methods as well as gonadectomized mice with selective hormone replacement. Lastly, in Aim 3 we will extend these studies to assess the intersection of HIV infection, a critical risk for TB, and sex differences in immunity. We will assess immune responses in samples from people living with HIV (PLWH) on ART versus healthy controls (HCs), specifically balancing groups for sex. We will evaluate the ability of whole blood and hMDM from PLWH and HCs to contain Mtb growth both alone and in the presence of DHEA. Lastly, we will assess transcriptomic responses in PBMCs from male and female PLWH and HCs following Mtb infection.