Senescence-Chips for Radiation Biodosimetry

项目摘要/摘要 放射性/核恐怖事件后急性和延迟性辐射损伤的理想生物标志物是 在组织损伤出现之前，通常在电离后一到几天内出现并可测量到 辐射(IR)暴露。它们还应该以非侵入性或微侵入性的方式进行测量--例如 例如，使用外周血液样本。大剂量IR对两种动物的急性和迟发性损伤 造血细胞和固体组织。造血干细胞(HSCs)和间质干细胞(MSCs) 对再生和修复这些组织至关重要。MSCs可分化为成骨细胞、软骨细胞和 脂肪细胞是各种血细胞的前体，而造血干细胞是各种血细胞的前体。我们发现造血干细胞和骨髓间充质干细胞 在IR后经历IR诱导的衰老，这是一个稳定的有丝分裂后状态。相比之下，分化程度最高的血液 IR后细胞发生凋亡，并迅速被清除。造血干细胞和间充质干细胞通常驻留在骨骼中。 骨髓，但总能从外周血中检测到并分离出少量。在这个SBIR项目中， 我们建议使用细胞衰老作为辐射生物剂量学的生物终点。我们将发展 集成的微流控芯片，称为“衰老芯片”，用于快速和准确地检测衰老细胞， 特别是IR诱导的衰老HSCs和MSCs，以及循环中的细胞因子/趋化因子 衰老相关分泌表型(SASP)，来自少量的人外周血。这个 该项目建立在我们最近发表的表征IR诱导的HSC衰老的进展的基础上，并 MSCs，SASP作为一种稳定的(慢性)衰老细胞表型，以及新小鼠的发育 模型(p16-3MR C57BL/6小鼠)，使我们能够识别、跟踪--重要的是，诱导地杀死--衰老 活体内和随意的细胞。我们的新型微流控芯片包含多个功能模块，将捕获和 计数HSCs和MSCs的总数和衰老群体，下至单个细胞，并同时 检测外周血中的SASP。这些芯片将使用细胞系、小鼠模型和人类进行验证 临床样本。衰老芯片将实现低成本、可重复、高度特异和敏感的多路传输 用于辐射生物剂量测定的人体外周血的测量，因此可用于现场部署 辐射/核医学对策平台，包括紧急分诊和医疗反应。

Project Summary/Abstract Ideal biomarkers of acute and delayed radiation injury after a radiological/nuclear terrorist incident are those that arise and are measurable prior to manifestation of tissue injuries, typically one to a few days after ionizing radiation (IR) exposure. They should also be measurable in a non-invasive or minimally invasive way -- for example, using peripheral blood samples. High-dose IR induces acute and delayed injuries to both hematopoietic and solid tissues. Hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs) are critical for regenerating and repairing these tissues. MSCs differentiate into osteoblasts, chondrocytes, and adipocytes while HSCs are precursors of various types of blood cells. We showed that HSCs and MSCs undergo IR-induced senescence, a stable post-mitotic state, after IR. In contrast, most differentiated blood cells undergo apoptosis after IR and are quickly cleared. HSCs and MSCs generally reside in the bone marrow, but small numbers can always be detected and isolated from peripheral blood. In this SBIR project, we propose to use cellular senescence as the biological end-point for radiation biodosimetry. We will develop integrated microfluidic chips, termed "Senescence-Chips", for rapid and accurate detection of senescent cells, particularly, IR-induced senescent HSCs and MSCs, as well as circulating cytokines/chemokines due to the senescence-associated secretory phenotype (SASP), from small volumes of human peripheral blood. The project builds on our recently published progress in characterizing the IR-induced senescence of HSCs and MSCs, the SASP as a stable (chronic) phenotype of senescent cells, and the development of a new mouse model (p16-3MR C57BL/6 mice) that allows us to identify, track - and, importantly, inducibly kill - senescent cells in vivo and at will. Our novel microfluidic chips contain multiple functional modules that will capture and enumerate the total and senescent populations of HSCs and MSCs, down to single cells, and simultaneously detect SASP, in peripheral blood. The chips will be validated using cell lines, mouse models, and human clinical samples. Senescence-chips will enable low-cost, reproducible, highly specific and sensitive multiplex measurements of human peripheral blood for radiation biodosimetry, thus serving as a field-deployable platform for radiological/nuclear medical countermeasures including emergency triage and medical responses.