Enríquez-de-Salamanca Amalia, Castellanos Evangelina, Stern Michael E, Fernández Itziar, Carreño Ester, García-Vázquez Carmen, Herreras Jose M, Calonge Margarita
Ocular Surface Group, IOBA-University of Valladolid, Campus Miguel Delibes, Valladolid, Spain.
Mol Vis. 2010 May 19;16:862-73.
Inflammatory molecules have been demonstrated in the tear film of patients with severe dry eye disease (DED). However, little attention has been paid to the most frequent moderate forms of DED. This study analyzes tear cytokine levels and their clinical correlations in patients with moderate evaporative-type DED due to meibomian gland disease (MGD).
Twenty three evaporative-type DED patients (46 eyes) of mild-to-moderate intensity and nine healthy subjects (18 eyes) were recruited. Two symptom questionnaires were self-answered and multiple DED-related clinical tests were performed. Unstimulated tears from each eye were isolated and were not pooled. Levels of 15 cytokines and chemokines were measured by multiplex bead analysis, compared with control levels, and correlated with clinical tests.
Fourteen out of the 15 molecules were reliably detected in 1 microl of unstimulated tears from DED patients. Epidermal growth factor (EGF), fractalkine/CX3CL1, interleukin (IL) 1-receptor antagonist (Ra), IL-8/CXCL8, interferon inducible protein (IP)-10/CXCL10, and vascular endothelial growth factor (VEGF) were found in 94%-100% of samples; IL-6 in 65% (significantly more detected in older patients); IL-1beta, interferon gamma (IFN-gamma), and IL-10 in 30%-48%; IL-17 in 13%; granulocyte macrophage colony stimulating factor (GM-CSF), IL-13, and tumor necrosis factor alpha (TNF-alpha) in 2%-9%; and IL-5 was never detected. EGF, fractalkine/CX3CL1, IL-1Ra, IP-10/CXCL10, and VEGF levels were significantly increased compared to normal controls. Pain was correlated with IL-6 and IL-8/CXCL8. Tear break-up time correlated inversely with IL1-Ra. Schirmer test and tear lysozyme levels negatively correlated with IL-1Ra, IL-8/CXCL8, fracktalkine/CX3CL1, IL-6, IP-10/CXCL10, and VEGF had the same tendency. Conjunctival staining correlated negatively with EGF and positively with IL-6.
In this sample of moderate evaporative-type DED patients, five inflammatory molecules were elevated. Fracktalkine was demonstrated to be present and elevated in tears in human DED. IL-1Ra, IL-6, IL-8/CXCL8, and EGF levels correlated with pain and with clinical parameters measuring tear stability, tear production or ocular surface integrity. These results suggest that inflammation plays a role not only in severe DED but also in moderate evaporative DED.
炎症分子已在重度干眼症（DED）患者的泪膜中得到证实。然而，对于最常见的中度DED形式关注较少。本研究分析了睑板腺功能障碍（MGD）所致中度蒸发型DED患者的泪液细胞因子水平及其临床相关性。
招募了23例轻度至中度强度的蒸发型DED患者（46只眼）和9名健康受试者（18只眼）。患者自行回答两份症状问卷，并进行多项与DED相关的临床检查。分离每只眼睛的未刺激泪液，不进行合并。通过多重微珠分析测量15种细胞因子和趋化因子的水平，与对照水平进行比较，并与临床检查结果相关联。
在DED患者1微升未刺激泪液中可靠检测到了15种分子中的14种。表皮生长因子（EGF）、趋化因子/CX3CL1、白细胞介素（IL）-1受体拮抗剂（Ra）、IL-8/CXCL8、干扰素诱导蛋白（IP）-10/CXCL10和血管内皮生长因子（VEGF）在94%-100%的样本中被检测到；IL-6在65%的样本中被检测到（在老年患者中检测到的数据明显更多）；IL-1β、干扰素γ（IFN-γ）和IL-10在30%-48%的样本中被检测到；IL-17在13%的样本中被检测到；粒细胞巨噬细胞集落刺激因子（GM-CSF）、IL-13和肿瘤坏死因子α（TNF-α）在2%-9%的样本中被检测到；而IL-5从未被检测到。与正常对照组相比，EGF、趋化因子/CX3CL1、IL-1Ra、IP-10/CXCL10和VEGF水平显著升高。疼痛与IL-6和IL-8/CXCL8相关。泪膜破裂时间与IL1-Ra呈负相关。泪液分泌试验和泪液溶菌酶水平与IL-1Ra、IL-8/CXCL8、趋化因子/CX3CL1、IL-6、IP-10/CXCL10呈负相关，VEGF也有相同趋势。结膜染色与EGF呈负相关，与IL-6呈正相关。
在这个中度蒸发型DED患者样本中，有五种炎症分子升高。趋化因子在人类DED患者的泪液中被证实存在且升高。IL-1Ra、IL-6、IL-8/CXCL8和EGF水平与疼痛以及测量泪液稳定性、泪液分泌或眼表完整性相关的临床参数相关。这些结果表明，炎症不仅在重度DED中起作用，在中度蒸发型DED中也起作用。
