Differential Expression of Tear Lymphotoxin-Α, Immunoglobulin E, and Matrix Metalloproteinase-9 in Allergic Conjunctivitis-Associated Dry Eye

To evaluate the expression differences of tear lymphotoxin-α (LT-α), total immunoglobulin E (IgE), and matrix metalloproteinase-9 (MMP-9) in seasonal/perennial allergic conjunctivitis-associated dry eye (S/PAC-DE) and their clinical relevance, probing the underlying pathogenesis of S/PAC-DE. This study enrolled 37 S/PAC-DE patients, 23 dry eye (DE) patients, and 24 healthy controls (HC). Assessing the clinical parameters, tear LT-α, total IgE, MMP-9, and nine other inflammatory cytokines in the three groups. Correlations between tear cytokines and clinical parameters were also analyzed. Tear LT-α levels were significantly lower in S/PAC-DE compared to DE and HC groups. Tear total IgE, TNF-α, and MMP-9 levels were significantly upregulated in the S/PAC-DE group than those in the DE (all <i>p</i> &lt; 0.001) and HC groups (<i>p</i> = 0.005, <i>p</i> &lt; 0.001, and <i>p</i> = 0.048). In the S/PAC-DE group, total IgE was positively correlated with MMP-9 (<i>r</i> = 0.652, <i>p</i> = 0.008). Total IgE and LT-α were positively correlated in the DE group (<i>r</i> = 0.498, <i>p</i> = 0.016), while the two showed a negative correlation trend in the S/PAC-DE group (r=-0.272, <i>p</i> = 0.103). LT-α was positively correlated with tear film break-up time and negatively correlated with corneal fluorescein staining score in both the S/PAC-DE and DE groups. In the S/PAC-DE co-morbid state, the inhibition of tear LT-α expression and the upregulation of the pro-inflammatory cytokines total IgE, TNF-α, and MMP-9 may collectively contribute to the disruption of the ocular surface epithelial barrier, further promoting and exacerbating DE. Additionally, the differences in correlation between LT-α and total IgE in the S/PAC-DE and common DE patients may be related to the distinct ocular immune microenvironments.本研究旨在评估泪液淋巴毒素α（lymphotoxin-α, LT-α）、总免疫球蛋白E（immunoglobulin E, IgE）及基质金属蛋白酶9（matrix metalloproteinase-9, MMP-9）在季节性/常年性变应性结膜炎相关性干眼症（seasonal/perennial allergic conjunctivitis-associated dry eye, S/PAC-DE）中的表达差异及其临床相关性，以探讨S/PAC-DE的潜在发病机制。本研究共纳入37例S/PAC-DE患者、23例干眼症（dry eye, DE）患者及24例健康对照（healthy controls, HC）。对三组受试者的临床参数、泪液LT-α、总IgE、MMP-9及另外9种炎症细胞因子进行检测，并分析泪液细胞因子与临床参数之间的相关性。结果显示：与DE组及HC组相比，S/PAC-DE组患者的泪液LT-α水平显著降低；而S/PAC-DE组的泪液总IgE、肿瘤坏死因子α（tumor necrosis factor-α, TNF-α）及MMP-9水平均显著高于DE组（均p<0.001）及HC组（分别为p=0.005、p<0.001及p=0.048）。在S/PAC-DE组中，总IgE与MMP-9呈正相关（r=0.652，p=0.008）；在DE组中，总IgE与LT-α呈正相关（r=0.498，p=0.016），而在S/PAC-DE组中二者则呈负相关趋势（r=-0.272，p=0.103）。在S/PAC-DE组与DE组中，LT-α均与泪膜破裂时间呈正相关，与角膜荧光素染色评分呈负相关。在S/PAC-DE共病状态下，泪液LT-α表达的抑制以及促炎细胞因子总IgE、TNF-α及MMP-9的上调，可能共同导致眼表上皮屏障破坏，进而促进并加重干眼症的发生发展。此外，S/PAC-DE患者与普通DE患者中LT-α与总IgE的相关性差异，可能与二者不同的眼表免疫微环境有关。