Spachidou M P, Bourazopoulou E, Maratheftis C I, Kapsogeorgou E K, Moutsopoulos H M, Tzioufas A G, Manoussakis M N
Department of Pathophysiology, Medical School, National University of Athens, Greece.
Clin Exp Immunol. 2007 Mar;147(3):497-503. doi: 10.1111/j.1365-2249.2006.03311.x.
Toll-like receptors (TLR) play an essential role in the activation of both innate and adaptive immune responses. Salivary gland epithelial cells (SGEC) may participate in the development of glandular inflammatory reactions that characterize primary Sjögren's syndrome (pSS). In this study we sought to assess the expression and function of several TLR molecules in cultured non-neoplastic SGEC obtained from pSS patients and disease controls. Long-term cultured non-neoplastic SGEC derived from pSS patients (SS-SGEC) and disease controls (control-SGEC), as well as the monocytic cell line THP-1 (positive control cell line), were examined by reverse transcription-polymerase chain reaction (RT-PCR) analysis and quantitative real-time PCR for mRNA expression of TLR1, -2, -3 and -4 molecules. TLR function was assessed by the induction of the expression (flow cytometry) of the immunoregulatory molecules CD54/intercellular adhesion molecule-1 (ICAM-1), CD40, CD86/B7 x 2, major histocompatibility complex (MHC) class I and MHC class II following treatment with the TLR ligands: Staphylococcus aureus peptidoglycan (TLR2), the synthetic dsRNA analogue polyinosinic:cytidylic acid (TLR3) and Escherichia coli lipopolysaccharide (TLR4). SGEC were found to express functional TLR2, -3 and -4 molecules, as attested by dose-dependent up-regulation of surface ICAM-1, CD40 and MHC-I expression (as well as of reciprocal TLR mRNA) following treatment with the respective TLR-ligands. SS-SGEC lines displayed significantly higher constitutive expression of TLR1 (P=0 x 0027), TLR2 (P=0 x 01) and TLR4 (P=0 x 03) mRNA compared to control-SGEC. This study demonstrates that cultured SGEC express functional TLR molecules; the high constitutive TLR expression by SS-SGEC is probably suggestive of the intrinsic activation of epithelial cells in pSS and further supports the role of this type of tissue in pathogenesis of the disorder.
Toll样受体（TLR）在先天性和适应性免疫反应的激活中发挥着重要作用。唾液腺上皮细胞（SGEC）可能参与了原发性干燥综合征（pSS）特征性的腺体炎症反应的发展。在本研究中，我们试图评估从pSS患者和疾病对照中获得的培养的非肿瘤性SGEC中几种TLR分子的表达和功能。通过逆转录-聚合酶链反应（RT-PCR）分析和定量实时PCR检测来自pSS患者（SS-SGEC）和疾病对照（对照-SGEC）的长期培养的非肿瘤性SGEC以及单核细胞系THP-1（阳性对照细胞系）中TLR1、-2、-3和-4分子的mRNA表达。通过用TLR配体处理后免疫调节分子CD54/细胞间粘附分子-1（ICAM-1）、CD40、CD86/B7 x 2、主要组织相容性复合体（MHC）I类和MHC II类的表达诱导（流式细胞术）来评估TLR功能：金黄色葡萄球菌肽聚糖（TLR2）、合成双链RNA类似物聚肌苷酸：胞苷酸（TLR3）和大肠杆菌脂多糖（TLR4）。发现SGEC表达功能性TLR2、-3和-4分子，在用各自的TLR配体处理后，表面ICAM-1、CD40和MHC-I表达（以及相应的TLR mRNA）呈剂量依赖性上调证明了这一点。与对照-SGEC相比，SS-SGEC系显示TLR1（P = 0.0027）、TLR2（P = 0.01）和TLR4（P = 0.03）mRNA的组成性表达显著更高。本研究表明，培养的SGEC表达功能性TLR分子；SS-SGEC的高组成性TLR表达可能提示pSS中上皮细胞的内在激活，并进一步支持这种类型的组织在该疾病发病机制中的作用。
