目的:虽然外部环境已被证明可以塑造人体全身免疫景观,定义外周组织的体内免疫状态仍然是一个技术挑战。我们最近开发了功能性体内共聚焦显微镜(Fun-IVCM),用于动态,活体角膜免疫细胞的纵向成像。这项研究调查了季节性驱动的环境因素对密度的影响,人角膜免疫细胞亚群的形态和动态行为。
方法:纵向,观察性临床研究。
方法:16名健康参与者(18-40岁)在墨尔本不同季节参加了两次访问,澳大利亚(访问1:春季/夏季:2021年11月至12月;访问2:秋季/冬季:2022年4月至6月)。
方法:收集每个时期的环境数据。参与者接受了眼表检查和角膜Fun-IVCM(海德堡HRT-3,罗斯托克角膜模块)。以5.5±1.5分钟的间隔采集体积扫描(80μm),最多五个时间点。制作延时视频来分析角膜免疫细胞,包括上皮T细胞和树突状细胞(DC),和基质巨噬细胞。使用基于多重珠的免疫测定分析泪液细胞因子。
方法:密度的差异,研究期间角膜免疫细胞亚群的形态学和动力学参数。
结果:第1次访问的特征是温度较高,湿度较低,空气颗粒物和花粉水平高于访问2。临床眼表参数,和免疫细胞亚群的密度是相似的。在访问1(春季/夏季),角膜上皮DC更大,更细长,以较低的枝晶探测速度(0.38±0.21vs0.68±0.33μm/min,p<0.001)相对于第2次;基质巨噬细胞更环状,动态活动更少(第1次访问:7.2±1.9vs第2次访问:10.3±3.7“跳舞指数”,p<0.001)。T细胞形态和动力学在不同时期没有变化。在春季/夏季,IL-2和CXCL10的基础撕裂水平较低。
结论:这项新研究表明,先天角膜免疫细胞的体内形态动力学(DCs,巨噬细胞)被环境因素修饰,但这种影响对于适应性免疫细胞(T细胞)并不明显。角膜是一种潜在的非侵入性,体内“窗口”以适应人类免疫系统的季节变化,有能力对环境对免疫调节的影响产生新的见解。
OBJECTIVE: Defining how the in vivo immune status of peripheral tissues is shaped by the external environment has remained a technical challenge. We recently developed Functional in vivo
confocal microscopy (Fun-IVCM) for dynamic, longitudinal imaging of corneal immune cells in living humans. This study investigated the effect of seasonal-driven environmental factors on the morphodynamic features of human corneal immune cell subsets.
METHODS: Longitudinal, observational clinical study.
METHODS: Sixteen healthy participants (aged 18-40 years) attended 2 visits in distinct seasons in Melbourne, Australia (Visit 1, November-December 2021 [spring-summer]; Visit 2, April-June 2022 [autumn-winter]).
METHODS: Environmental data were collected over each period. Participants underwent ocular surface examinations and corneal Fun-IVCM (Heidelberg Engineering). Corneal scans were acquired at 5.5 ± 1.5-minute intervals for up to 5 time points. Time-lapse Fun-IVCM videos were created to analyze corneal immune cells, comprising epithelial T cells and dendritic cells (DCs), and stromal macrophages. Tear cytokines were analyzed using a multiplex bead-based immunoassay.
METHODS: Difference in the density, morphology, and dynamic parameters of corneal immune cell subsets over the study periods.
RESULTS: Visit 1 was characterized by higher temperature, lower humidity, and higher air particulate and pollen levels compared with Visit 2. Clinical ocular surface parameters and the density of immune cell subsets were similar across visits. At Visit 1 , corneal epithelial DCs were larger, with a lower dendrite probing speed (0.38 ± 0.21 vs. 0.68 ± 0.33 μm/min; P < 0.001) relative to Visit 2; stromal macrophages were more circular and had less dynamic activity (Visit 1, 7.2 ± 1.9 vs. Visit 2, 10.3 ± 3.7 dancing index; P < 0.001). Corneal T cell morphodynamics were unchanged across periods. Basal tear levels of interleukin 2 and CXCL10 were relatively lower during spring-summer.
CONCLUSIONS: This study identifies that the in vivo morphodynamics of innate corneal immune cells (DCs, macrophages) are modified by environmental factors, but such effects are not evident for adaptive immune cells (T cells). The cornea is a potential in vivo window to investigate season-dependent environmental influences on the human immune system.
BACKGROUND: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.