Towards an in vitro model of biocompatibility testing in the closed eye: tear film neutrophil phenotype and healthy host innate immune responses

炎症是细胞对诸如接触透镜和支架的生物医学装置的反应的组成部分。尽管经过多年的研究，我们还没有开发出能够与人体相互作用而不会引起并发症的材料。要设计出与人体生物系统兼容的材料，首先必须了解细胞如何与材料相互作用。此外，需要适当的实验（体外）模型来测试在适当模拟研究的生物系统的环境中的细胞反应。对于眼睛来说尤其如此，中性粒细胞，炎性白色血细胞，在长时间的闭眼期间（1小时或更长时间，因此每天晚上我们睡觉时）侵入眼睛前部。这些嗜中性粒细胞具有对抗感染和异物的炎性化合物，有可能严重损害眼表。然而，虽然在闭上的眼睛中可以发现数十万个活的炎性细胞，但我们的早期结果表明，这些中性粒细胞对炎症刺激的反应能力有限。这些细胞的行为是由于它们与其他细胞的相互作用，由于特定泪液化合物的存在，还是它们是不同类型的中性粒细胞？ 这项研究提出了充分表征闭上眼睛的中性粒细胞对炎症刺激和细菌的反应，研究它们释放的化合物及其吞噬细菌的能力。本研究采用体外机械方法，旨在更好地了解所涉及的细胞机制。从血管到眼表的迁移过程的体外模型将允许确定这如何影响存在于闭合的眼睛中的嗜中性粒细胞的反应。使用各种细胞培养条件，这些迁移的中性粒细胞将与不同的泪液蛋白一起孵育，并与角膜和结膜细胞相互作用。泪液蛋白、炎性化合物和与细胞的相互作用在保护眼睛免受损伤和睡眠时中性粒细胞炎症反应中的作用（包括在生物材料存在下）将使用精心设计的体外模型来确定。这项研究计划将创造关于眼部环境中炎症机制的新知识，以及生物材料如何影响闭眼中的炎症反应以及如何在体外测试。这将有助于确定关键的分子途径，并使制造商能够开发更好的眼部药物和材料，以防止眼部损伤和保护视力。该计划将培养四名研究生进行跨学科研究，使用与细胞生物学，体外模型和材料相互作用相关的方法。学生将获得的专业知识将使他们能够加入迅速崛起和至关重要的加拿大生物医学和生物技术行业。

Inflammation is an integral part of the cell response to biomedical devices such as contact lens and stent. Despite many years of research, we have yet to develop materials that are able to interact with the human body without causing complications. To design materials that are compatible with human biological systems, one must first understand how cells interact with materials. Furthermore, appropriate experimental (in vitro) models are needed to test cell response in an environment that appropriately mimics the biological system of study. This is especially true for the eye, with neutrophils, inflammatory white blood cells, invading the front of the eye during prolonged eye closure (1hr or more, and thus every night as we sleep). With their arsenal of inflammatory compounds aimed at fighting off infection and foreign materials, these neutrophils have the potential to significantly damage the ocular surface. However, while hundreds of thousands of live inflammatory cells can be found in the closed-eye, our early results indicate that these neutrophils have a limited ability to respond to inflammatory stimuli. Is the behavior of these cells due to their interactions with other cells, due to the presence of specific tear compounds or are they a different type of neutrophils? This research proposed to fully characterize the response of neutrophils from the closed eye to inflammatory stimuli and bacteria, studying the compounds they release and their ability to eat bacteria. Using a mechanistic in vitro approach, this research aims to gain a better understanding of the cellular mechanisms involved. An in vitro model of the migration process from the blood vessel to the ocular surface will allow to determine how this affects the response of the neutrophils present in the closed eye. Using various cell culture conditions, these migrated neutrophils will then be incubated with different tear proteins and interact with corneal and conjunctival cells. The role that tear proteins, inflammatory compounds and interaction with cells play in protecting the eye from damage and in the neutrophil inflammatory response while we sleep (including in the presence of a biomaterial) will be determined using carefully designed in vitro models. This research program will create new knowledge on mechanisms of inflammation in the ocular environment and how a biomaterial may affect inflammatory response in the closed eye and how to test this in vitro. This will help identify key molecular pathways and enable novel strategies for manufacturers to develop better ocular pharmaceuticals and materials to prevent ocular damage and preserve vision. This program will train four graduate students in interdisciplinary research using methodologies related to cell biology, in vitro model and interaction with materials. The expertise students will gain will allow them to join the rapidly emerging and critically important Canadian biomedical and biotechnology industry.