type I interferon regulates angiogenesis in Down Syndrome

项目摘要 21三体（T21）是世界范围内最普遍的染色体异常，导致唐氏综合征（DS）。 [1，2]，一种与心肺疾病相关的多系统综合征。肺部疾病包括 肺动脉高压、肺发育不全、肺含铁血黄素沉着症和肺毛细血管炎， 这可能是由于肺内皮细胞失调引起的。此外，T21肺的特征在于 肺泡周围存在不成熟的双毛细血管网络系统， 囊状发育阶段[3]。这表明DS患者的内皮缺陷可能是由 在子宫里单细胞转录组学数据表明，在内皮细胞中存在不同的内皮细胞群。 成人肺[4，5]。虽然其他人和我们已经报道了在发展中国家受损的内皮网络， T21肺以毛细血管充血、淋巴管扩张和肌化动脉为特征[6]， 这些缺陷和导致这些缺陷的不同内皮细胞群的研究还有待于进一步深入。 明白此外，发育中的T21人肺显示抗血管生成因子的表达增加[3， 6-8]。在T21外周血中发现内皮祖细胞减少[9]。T21 iPSC- 衍生的内皮细胞显示出细胞增殖降低、发芽和管形成受损， 整倍体细胞[10]。在DS中持续激活的主要途径之一是I型干扰素（IFN）途径 [6]的文件。升高的I型IFN导致内皮祖细胞减少[9]，并抑制VEGF诱导的内皮祖细胞增殖。 毛细血管样结构的发展[11，12]，从而起到抗血管生成作用。此外，I型 干扰素病与肺动脉高压和肺血管病有关[13]。Sc-RNAseq数据 T21和整倍体肺细胞证明存在几种内皮细胞群，显示出 增加T21中I型IFN信号传导途径基因的表达。因此，我们假设， 肺血管生成发生在发育过程中的T21中，是I型IFN依赖性变化的结果， 内皮细胞增殖、分化和迁移。为了验证这一假设，我们将1）确定内皮细胞 通过定义不同的内皮细胞群， 它们的时空分布使用组合原位杂交与IF染色和评估缺陷 通过IF和3D图像定量，确定各组的内皮细胞增殖和发芽， 通过确定I型IFN信号的获得和丧失的影响，I型IFN信号在T21中的内皮缺陷中的作用 IFN信号对原代和iPSC衍生内皮细胞增殖、迁移、渗透性和管道形成的影响 T21和整倍体细胞的细胞培养物。预防、改善或逆转内皮相关疾病的改进策略 DS中的肺部疾病将取决于对这些缺陷和驱动这些缺陷的途径的详细理解。 这些缺陷可以识别新的治疗靶点进行干预。

PROJECT SUMMARY Trisomy 21 (T21) is the most prevalent chromosomal abnormality worldwide, resulting in Down Syndrome (DS) [1, 2], a multisystem syndrome associated with cardiopulmonary disorders. Pulmonary disorders include pulmonary hypertension, pulmonary hypoplasia, pulmonary hemosiderosis and pulmonary capillaritis, all of which can result from a dysregulated lung endothelium. In addition, T21 lungs are characterized by the persistence of an immature double capillary network system surrounding the alveoli and representative of the saccular stage of development [3]. This suggests that endothelial defects in individuals with DS are likely initiated in utero. Single cell transcriptomics data demonstrated the presence of diverse endothelial cell populations in the human adult lung [4, 5]. While others and we have reported impaired endothelial networks in the developing T21 lung characterized by congested capillaries, lymphatic dilatation, and muscularized arteries [6], the nature of these defects and the different endothelial cell populations contributing to such defects are yet to be understood. Moreover, developing T21 human lungs display increased expression of anti-angiogenic factors [3, 6-8]. A decrease in endothelial progenitor cells is found in T21 peripheral blood [9]. Furthermore, T21 iPSC- derived endothelial cells exhibit decreased cell proliferation, impaired sprouting and tube formation compared to euploid cells [10]. One of the major pathways consistently activated in DS is the type I interferon (IFN) pathway [6]. Elevated type I IFN causes a decrease of endothelial progenitor cells [9] and inhibits VEGF induced development of capillary like structures [11, 12], thus playing an anti-angiogenic role. Additionally, type I interferonopathies are linked to pulmonary hypertension and pulmonary vasculopathy [13]. Sc-RNAseq data of T21 and euploid lung cells demonstrated the presence of several endothelial cell populations displaying increased expression of type I IFN signaling pathway genes in T21. Therefore, we hypothesize that defective lung angiogenesis occurs in T21 during development and is a result of type I IFN-dependent changes in endothelial cell proliferation, differentiation and migration. To test this hypothesis, we will 1) determine endothelial cell defects in T21 vs euploid human developing lungs by defining the different endothelial cell populations and their spatiotemporal distribution using combinatorial in situ hyridization with IF stainings and assessing defects in endothelial cell proliferation and sprouting of each group via IF and 3D image quantifications and 2) define the role of type I IFN signaling in the endothelial defects in T21 by determining the effect of gain and loss of type I IFN signaling on proliferation, migration, permeability and tube formation in primary and iPSC-derived endothelial cell cultures of T21 and euploid cells. Improved strategies to prevent, ameliorate or reverse endothelial related lung disease in DS will be contingent upon a detailed understanding of the defects and pathways driving these defects that may identify novel therapeutic targets for intervention.