Wang Yingming, Gao Jing, Wu Tianhong, Wang Zhenyu
Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
Ocul Immunol Inflamm. 2025 May 6:1-10. doi: 10.1080/09273948.2025.2497484.
Dry eye disease (DED) is a chronic, progressive, multifactorial condition characterized by tear film instability and ocular surface damage. Ocular surface inflammation is one of the main mechanisms of DED. This study aims to investigate the therapeutic effects of anti-inflammatory M2 macrophages on ocular surface inflammation and their potential mechanisms in improving dry eye symptoms in a mouse model.
Mouse macrophages (RAW264.7) were polarized into M2 macrophages by IL-4 under different osmolarities, and M2 macrophage conditioned medium (M2-CM) was collected. Flow cytometry and ELISA were applied to measure the cytokine expression of the M2 macrophages. Primary mouse corneal epithelial cells (CECs) were co-cultured with RAW264.7 and M2 macrophages using a Transwell system. The viability and migration of CECs were assessed using CCK-8 and scratch assays. Mouse DED was established by subcutaneous injection of scopolamine, and the therapeutic effects of M2-CM were evaluated by phenol red thread test, fluorescein staining, and tear film breakup time (BUT). PCR and immunofluorescence staining were applied to observe inflammatory factors and cells on the ocular surface.
M2 macrophages enhanced CEC viability, proliferation, and migration, but hyperosmolarity inhibited M2 macrophage polarization. In the DED model, M2-CM improved ocular surface conditions, reduced pro-inflammatory cytokine expression, and increased anti-inflammatory factors. Immunofluorescence revealed reduced pro-inflammatory cells (M1 macrophages, Th1, and Th17) and increased M2 macrophages in the ocular tissues after M2-CM treatment.
These results suggest that M2-CM ameliorates ocular surface inflammation and promotes recovery in DED, offering a potential therapeutic strategy for DED.
干眼症（DED）是一种慢性、进行性、多因素疾病，其特征为泪膜不稳定和眼表损伤。眼表炎症是干眼症的主要发病机制之一。本研究旨在探讨抗炎性M2巨噬细胞对眼表炎症的治疗作用及其改善小鼠干眼症症状的潜在机制。
在不同渗透压条件下，用白细胞介素-4将小鼠巨噬细胞（RAW264.7）极化为M2巨噬细胞，并收集M2巨噬细胞条件培养基（M2-CM）。采用流式细胞术和酶联免疫吸附测定法检测M2巨噬细胞的细胞因子表达。使用Transwell系统将原代小鼠角膜上皮细胞（CECs）与RAW264.7和M2巨噬细胞共培养。采用CCK-8法和划痕试验评估CECs的活力和迁移能力。通过皮下注射东莨菪碱建立小鼠干眼症模型，并用酚红棉线试验、荧光素染色和泪膜破裂时间（BUT）评估M2-CM的治疗效果。采用聚合酶链反应（PCR）和免疫荧光染色观察眼表的炎症因子和细胞。
M2巨噬细胞增强了CECs的活力、增殖能力和迁移能力，但高渗抑制了M2巨噬细胞的极化。在干眼症模型中，M2-CM改善了眼表状况，降低了促炎细胞因子的表达，并增加了抗炎因子。免疫荧光显示，M2-CM治疗后，眼组织中促炎细胞（M1巨噬细胞、Th1和Th17）减少，M2巨噬细胞增加。
这些结果表明，M2-CM可改善眼表炎症并促进干眼症的恢复，为干眼症提供了一种潜在的治疗策略。
