Silk-Based Blood Sample Stabilization for Prostate Cancer Diagnostics

 描述（由申请人提供）迫切需要一种血液样品制备和处理方法，其可以保持完整性并改善下游分析，同时完全没有冷藏要求。这种技术将允许临床医生和患者从患者家中舒适地收集用于癌症筛查、监测和/或诊断的血液样本，从而消除对门诊实验室访问的需要。Vaxess Technologies正在开发一套基于生物材料的方法，该方法使用新型丝蛋白基质来提高各种样品的稳定性。该提议的目的是表征丝基质稳定血液样品中代谢组学前列腺癌生物标志物组的能力。将丝基保护的增强性能与其他类似方法（干血斑（DBS）卡）和金标准（冷冻储存）进行比较。我们预计，丝的使用将允许微创或非侵入性的样品采集途径，并将提供与当前金标准冷冻储存相当的分析物保留，同时与市售DBS卡相比提高回收率。Vaxess有大量的初步数据证明使用蚕丝稳定来自复杂流体（如全血、血浆、血清和唾液）的抗体、血浆蛋白和核酸。我们期望能够对血液分析物做同样的事情，就像这里提出的那样。在第一个目标中，我们将形成载有血清的丝基质并定量代谢组学前列腺癌标志物水平。这将通过使用质谱法测量丝基质中的分析物回收率并将产率直接与冷冻对照或DBS卡进行比较来实现。丝分子量及其净电荷的修饰可以系统地改变蛋白质组相互作用，从而提供了一种途径来研究在样品回收的背景下丝稳定化的机制基础。在第二个目标中，我们将比较目标1中确定的标记物与冷冻对照样品和DBS卡在不同温度和湿度水平下处理时的稳定性。这些研究的预期结果将是开发一种用于癌症特异性分析物的基于丝的样品制备方法，该方法将改善下游样品处理。这项研究的基本原理是，一旦这些生物标志物的回收和稳定性被证明可以通过丝包封来增强，诊断试剂盒就可以配备各种丝形式，然后可以用作后续研究中全面验证的平台系统。计划方法的成功可以积极影响癌症诊断领域的许多需求领域，包括早期检测，筛查和临床诊断，通过增加对精确分析的整体访问和减少影响样本质量的分析前变化。此外，通过提供与手指针刺量的全血接口的方法，可以在没有抽血师的情况下使用基于丝的稳定系统，从而规避门诊诊所的资源需求。

 DESCRIPTION (provided by applicant) There is a critical need for a blood sample preparation and processing method that can preserve integrity and improve downstream analysis, while being completely free of cold storage requirements. Such a technology would allow clinicians and patients to collect blood samples for cancer screening, monitoring and/or diagnosis comfortably from patient's homes, obviating the need for outpatient lab visits. Vaxess Technologies is developing a set of biomaterial-based approaches that improves the stability of a wide range of samples using a novel silk protein matrix. The objective of this proposal is to characterize the ability of a silk matrix to stabilize a panel of metabolomic prostate cancer biomarkers in a blood sample. The enhanced performance of silk- based protection will be compared to other similar methods (dried blood spot (DBS) cards) and the gold standard (frozen storage). We anticipate that the use of silk will allow for minimally- or non-invasive sample collection routes, and will provide comparable analyte retention to the current gold standard, frozen storage, while improving recovery as compared to commercially-available DBS cards. Vaxess has extensive preliminary data demonstrating the use of silk to stabilize antibodies, plasma proteins and nucleic acids from complex fluids such as whole blood, plasma, serum, and saliva. We anticipate being able to do the same with blood analytes, as proposed here. In the first aim, we will form serum-laden silk matrices and quantitate metabolomic prostate cancer marker levels. This will be accomplished by using mass spectrometry to measure analyte recovery from silk matrices and comparing the yields directly to frozen controls or DBS cards. Modifications of silk molecular weight and its net charge can systematically change proteomic interactions, and thus provides a route to study the mechanistic underpinnings of silk stabilization in the context of sample recovery. In a second aim, we will compare the stability of markers identified in Aim 1 to frozen control samples and DBS cards when all have been treated at various temperatures and humidity levels. The expected outcome of these studies will be the development of a silk-based sample preparation method for cancer-specific analytes that will improve downstream sample processing. The rationale for the proposed research is that, once recovery and stability of these biomarkers is proven to be augmented by a silk encapsulate, diagnostic kits can be outfitted with various silk formats, which can then be used as a platform system for full validation in follow-on studies. Success with the planned approach can positively impact many areas of need in the field of cancer diagnostics, including early detection, screening, and clinical diagnosis, by increasing overall access to precise analytics and by reducing pre-analytical variations that affect sample quality. Furthermore, by offering methods to interface with finger-prick volumes of whole blood, a silk-based stabilization system could be used without a phlebotomist and thus circumvent the resource requirements of the outpatient clinic.