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

炎症是细胞对隐形眼镜和支架等生物医学设备反应的组成部分。尽管进行了多年的研究，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。要设计与人类生物系统兼容的材料，首先必须了解细胞与材料是如何相互作用的。此外，需要适当的实验(体外)模型来测试细胞在适当模拟生物研究系统的环境中的反应。对于眼睛来说尤其如此，中性粒细胞，炎性白细胞，在长时间闭眼期间(1小时或更长时间，因此每晚我们睡觉时)侵入眼睛前部。由于这些中性粒细胞含有大量炎性化合物，旨在抵御感染和异物，因此有可能对眼表造成严重损害。然而，虽然在闭眼时可以发现数十万活的炎症细胞，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，还是它们是一种不同类型的中性粒细胞？这项研究建议充分表征中性粒细胞从闭眼到对炎性刺激和细菌的反应，研究它们释放的化合物和它们吃掉细菌的能力。使用体外机制的方法，这项研究的目的是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闭合眼睛中存在的中性粒细胞的反应。在不同的细胞培养条件下，这些迁移的中性粒细胞将与不同的泪液蛋白孵育，并与角膜和结膜细胞相互作用。泪液蛋白、炎症化合物和与细胞的相互作用在保护眼睛免受损害以及在我们睡眠时(包括在生物材料存在的情况下)中性粒细胞炎症反应中所起的作用将通过精心设计的体外模型来确定。这项研究计划将创造新的知识，了解眼睛环境中的炎症机制，生物材料材料如何影响闭眼的炎症反应，以及如何在体外测试这种反应。这将有助于确定关键的分子途径，并为制造商开发更好的眼科药物和材料以防止眼睛损伤和保护视力提供新的策略。该计划将培训四名研究生，使用与细胞生物学、体外模型和材料相互作用相关的方法进行跨学科研究。学生将获得的专业知识将使他们能够加入迅速崛起且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.