Development of a prototype micro fluidic device for the study of cell function within a tissue environment

赫尔大学的微反应器研究小组目前已经进行了超过200人年的研究，以建立基本的设计和操作参数，例如通道形状，大小，流动方法和表面功能化，这使得微流体装置在分析化学领域具有显着的优势。最近，这项工作已经扩展到细胞生物学领域，现在与赫尔大学的细胞过程小组进行了许多正在进行的合作项目。总的来说，除了需要小样本量外，微流体方法的主要实际优势可以概括为提供(i)对层流状态下发生的扩散混合过程产生的过程进行非常高程度的空间（纳米）和时间（微秒）控制的设备；（ii）产生极高的表面体积比的可能性，以加强液体/表面或表面/表面的相互作用；（iii）将复杂过程与非侵入性分析测量相结合的机会，以获得比目前可能的更好的动态过程的时间和空间分辨率。目前，赫尔大学的主要工作是开发基于法医/环境和药物发现过程的集成过程/测量设备，涉及来自一系列科学和工程学科的约28名研究人员。鉴于赫尔大学对开发综合细胞处理和测量技术的支持，将当前的提案与正在进行的工作结合起来，同时在组织研究中发展独特的重点，似乎是及时和有利的。因此，通过将新科学与大量重要的研究和专门知识结合起来，拟议的资助将实现相当大的附加价值。因此，我们建议利用赫尔大学研究人员的专业知识，在组织处理领域建立（微流体）和开发（生物医学）微流体方法，并通过这样做，在研究科学家和临床医生之间建立独特的联系。例如，从一个小的活检中获得的生物组织，代表了排列在复杂的非细胞结构内的细胞类型的复杂聚集，支持细胞间的连接。然而，维持一个稳定的组织样本用于实验室研究已被证明是非常困难的，因为营养物质的输送、废物的去除和气体交换都需要实现。在自然界中，这些过程是通过一个复杂的血液和淋巴管网络进行的，它给组织提供了动态的灌注。微流体系统以其高表面体积比、固有的快速灌注和局部（单细胞）询问能力模拟自然，因此为开发包含集成测量能力的新技术提供了理想的微环境。提出的微流体装置将使细胞功能和细胞外（EC）基质在正常和病变组织中的作用的研究以一种新的方式进行。反过来，这将导致对细胞和组织生物学的理解取得重大的科学进展。在这个项目中，细胞之间的EC环境将使用一系列试剂来调节，这些试剂将以一种明确和可控的方式改变化学和生物相互作用。然后用药物样化合物测试条件组织，条件作用（即改变的EC环境）可用于确定单个细胞相互作用的重要性。例如，组织可以用钙抑制剂如EDTA来调节，它会破坏整合素的功能（一个参与细胞结合的细胞表面分子家族），允许组织在其他方面保持不变，以测试对细胞毒性药物的反应，以确定整合素在介导药物活性中的作用。

The Micro Reactor Research Group at Hull has now carried out over 200 man-years of research, to establish the fundamental design and operational parameters e.g. channel shape, size, flow methodology and surface functionalisation, that give micro fluidic devices significant advantages in the field of analytical chemistry. Recently this work has been extended into the field of cell biology and now features a number of ongoing collaborative projects with the Cellular Processes Group at Hull. In general the main practical advantages of micro fluidic methodology, apart from requiring small sample sizes, can be summarised as devices which offer (i) a very high degree of spatial (nano meter) and temporal (micro second) control of processes originating from diffusive mixing processes occurring within a laminar flow regime; (ii) the possibility of generating extremely high surface to volume ratios to intensify liquid/surface or surface/surface interactions and (iii) the opportunity to integrate complex processes with non-invasive analytical measurements in order to achieve significantly better temporal and spatial resolution of dynamic processes than is currently possible. At present the main thrust of the work at Hull is to develop integrated process/measurement devices for forensic/environmental and drug discovery based processes which involves approximately 28 research staff drawn from a range of scientific and engineering disciplines. Given the support at Hull to develop integrated cellular processing and measurement technology it would seem timely and advantageous to align this current proposal with ongoing work whilst developing a unique focus in tissue based research. Thus by combining new science with a significant critical mass of research and know-how considerable added value will be achieved with the proposed funding. We propose therefore to use the expertise that resides within the pool of researchers at Hull to establish (micro fluidic) and exploit (biomedical) micro fluidic methodology in the area of tissue processing and by doing so establish a unique link between research scientists and clinicians. Biological tissue obtained, for example, from a small biopsy, represents a complex aggregation of cell types arranged within an intricate non-cellular structure which supports intercellular connections. However, maintaining a stable tissue sample for study in the laboratory has proved to be very difficult as nutrient delivery, removal of waste products and gaseous exchange all need to be achieved. In nature these processes are carried out via a complex network of blood and lymphatic vessels which give dynamic perfusion of the tissue. Micro fluidic systems mimic nature with their high surface to volume ratio, inherent fast perfusion and localised (single cell) interrogation capability, and so offer an ideal microenvironment for the development of novel technology encompassing integrated measurement capability. The proposed micro fluidic devices will enable the study of cell function and the role of the extracellular (EC) matrix in normal and diseased tissues to be carried out in a novel way. This in turn will lead to significant scientific advances in the understanding of cell and tissue biology. In this project the EC environment between cells will be conditioned using a selection of reagents that will modify the chemical and biological interactions in a defined and controlled way. By then testing the conditioned tissue with a drug-like compound, the effect of conditioning (i.e. modified EC environment) can be used to identify the importance of individual cell interactions. For example, tissue could be conditioned with a calcium inhibitor e.g. EDTA which will disrupt integrin function (a family of cell surface molecules involved in cell binding) allowing the tissue, which is otherwise unchanged, to be tested for responses to cytotoxic drugs in order to identify the role of integrins in mediating drug activity.