Ji Yong Woo, Seo Yuri, Choi Wungrak, Yeo Areum, Noh Hyemi, Kim Eung Kweon, Lee Hyung Keun
Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea.
Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea Institute of Corneal Dystrophy Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea.
Invest Ophthalmol Vis Sci. 2014 Sep 25;55(10):6829-38. doi: 10.1167/iovs.14-14744.
We aimed to determine the role of CCR7+CD11b+ cell lymph node (LN) homing and T-cell differentiation in dry eye (DE)-induced immunopathogenesis and investigate the therapeutic effects of cyclooxygenase-2 (COX-2) and prostaglandin E2/eicosanoid-prostanoid (PGE2/EP) inhibitors against DE.
Six-week-old female C57BL/6 mice were housed in a controlled-environment chamber and administered topical selective COX-2 inhibitors or EP2 antagonists. Expression of major histocompatibility complex (MHC)-IIhigh, CD11b+, CCR7+, IFN-γ+, IL-17+, and CD4+ in the corneas and draining LNs was evaluated using flow cytometry. Mixed lymphocyte reactions (MLRs) with carboxyfluorescein diacetate succinimidyl ester labeling and intracellular cytokine staining were used to verify DE-induced corneal dendritic cell function. mRNA expression of COX-2, EPs, and proinflammatory cytokines in ocular surface was evaluated using quantitative RT-PCR and immunohistochemical staining.
Dry eye significantly increased MHC-IIhighCD11b+ and CCR7+CD11b+ cells in the cornea and LNs, and MLR revealed CCR7+CD11b+ cells from DE corneas stimulated IL-17+CD4+ cell proliferation. mRNA levels of COX-2, EP2, IFN-γ, TNF-α, IL-6, and IL-17 were significantly higher in DE ocular surface but were suppressed by topical COX-2 inhibitors and EP2-specific blockers. Immunohistochemical staining showed COX-2 and matrix metalloproteinase expression in DE corneal epithelia that was diminished by both topical treatments. Furthermore, both topical treatments significantly reduced frequencies of MHC-IIhigh, CD11b+, and CCR7+CD11b+ cells in the corneas and LNs, but also IL-17+CD4+ cells in LNs.
Topical COX-2/EP2 treatment reduces CCR7+CD11b+ cells on the ocular surface with inhibition of cellular LN homing and suppresses Th17 immune response, suggesting the COX-2/PGE2/EP axis contributes to immuno-inflammatory pathogenesis on the ocular surface and may be a novel therapeutic target in DE.
我们旨在确定CCR7⁺CD11b⁺细胞归巢至淋巴结（LN）以及T细胞分化在干眼（DE）诱导的免疫发病机制中的作用，并研究环氧合酶-2（COX-2）和前列腺素E2/类花生酸-前列腺素（PGE2/EP）抑制剂对DE的治疗效果。
将6周龄雌性C57BL/6小鼠饲养在可控环境舱中，并局部给予选择性COX-2抑制剂或EP2拮抗剂。使用流式细胞术评估角膜和引流淋巴结中主要组织相容性复合体（MHC）-II高表达、CD11b⁺、CCR7⁺、IFN-γ⁺、IL-17⁺和CD4⁺的表达。采用羧基荧光素二乙酸琥珀酰亚胺酯标记和细胞内细胞因子染色的混合淋巴细胞反应（MLR）来验证DE诱导的角膜树突状细胞功能。使用定量逆转录聚合酶链反应和免疫组织化学染色评估眼表中COX-2、EP和促炎细胞因子的mRNA表达。
干眼显著增加了角膜和淋巴结中MHC-II高表达CD11b⁺和CCR7⁺CD11b⁺细胞，并且MLR显示来自DE角膜的CCR7⁺CD11b⁺细胞刺激了IL-17⁺CD4⁺细胞增殖。DE眼表中COX-2、EP2、IFN-γ、TNF-α、IL-6和IL-17的mRNA水平显著更高，但局部COX-2抑制剂和EP2特异性阻滞剂可抑制这些水平。免疫组织化学染色显示DE角膜上皮中COX-2和基质金属蛋白酶的表达，两种局部治疗均可使其减少。此外，两种局部治疗均显著降低了角膜和淋巴结中MHC-II高表达、CD11b⁺和CCR7⁺CD11b⁺细胞的频率，以及淋巴结中IL-17⁺CD4⁺细胞的频率。
局部COX-2/EP2治疗可减少眼表的CCR7⁺CD11b⁺细胞，抑制细胞向淋巴结归巢，并抑制Th17免疫反应，提示COX-2/PGE2/EP轴在眼表免疫炎症发病机制中起作用，可能是DE的一个新治疗靶点。
