Mazzon E, Esposito E, Di Paola R, Muià C, Crisafulli C, Genovese T, Caminiti R, Meli R, Bramanti P, Cuzzocrea S
Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine, University of Messina, Messina, Italy.
Clin Exp Immunol. 2008 Jul;153(1):136-49. doi: 10.1111/j.1365-2249.2008.03669.x. Epub 2008 May 26.
In the present study, we used tumour necrosis factor-alpha receptor 1 knock-out mice (TNF-alphaR1KO) to evaluate an in vivo role of TNF-alphaR1 on the pathogenesis of inflammatory diseases. We used a murine model of carrageenan-induced acute inflammation (pleurisy), a preclinical model of airway inflammation. The data proved that TNF-alphaR1KO were resistant to carrageenan-induced acute inflammation compared with TNF-alpha wild-type mice. TNF-alphaR1KO showed a significant reduction in accumulation of pleural exudate and in the number of inflammatory cells, in lung infiltration of polymorphonuclear leucocytes and lipid peroxidation and showed a decreased production of nitrite/nitrate in pleural exudates. Furthermore, the intensity and degree of the adhesion molecule intercellular adhesion molecule-1 and P-selectin, Fas ligand (FasL), inducible nitric oxide sythase and nitrotyrosine determined by immunohistochemical analysis were reduced markedly in lung tissues from TNF-alphaR1KO at 4 h and 24 h after carrageenan injection. Moreover, TNF-alpha and interleukin-1beta concentrations were reduced in inflamed areas and in pleural exudates from TNF-alphaR1KO. To support the results generated using pleural inflammation, carrageenan-induced paw oedema models were also performed. In order to elucidate whether the observed anti-inflammatory effects were related to the inhibition of TNF-alpha, we also investigated the effect of etanercept, a TNF-alpha soluble receptor construct, on carrageenan-induced pleurisy. The treatment with etanercept (5 mg/kg subcutaneously 2 h before the carrageenan injection) reduces markedly both laboratory and histological signs of carrageenan-induced pleurisy. Our results showed that administration of etanercept resulted in the same outcome as that of deletion of the TNF-alphaR1 receptor, adding a new insight to TNF-alpha as an excellent target by therapeutic applications.
在本研究中，我们使用肿瘤坏死因子-α受体1基因敲除小鼠（TNF-αR1KO）来评估TNF-αR1在炎症性疾病发病机制中的体内作用。我们使用了角叉菜胶诱导的急性炎症（胸膜炎）小鼠模型，这是一种气道炎症的临床前模型。数据证明，与TNF-α野生型小鼠相比，TNF-αR1KO对角叉菜胶诱导的急性炎症具有抗性。TNF-αR1KO的胸腔渗出液积聚和炎症细胞数量显著减少，多形核白细胞在肺部的浸润和脂质过氧化减少，胸腔渗出液中亚硝酸盐/硝酸盐的产生也减少。此外，通过免疫组织化学分析测定，在注射角叉菜胶后4小时和24小时，TNF-αR1KO肺组织中的黏附分子细胞间黏附分子-1和P-选择素、Fas配体（FasL）、诱导型一氧化氮合酶和硝基酪氨酸的强度和程度明显降低。此外，TNF-αR1KO炎症部位和胸腔渗出液中的TNF-α和白细胞介素-1β浓度降低。为了支持使用胸膜炎模型得出的结果，还进行了角叉菜胶诱导的爪肿胀模型实验。为了阐明观察到的抗炎作用是否与TNF-α的抑制有关，我们还研究了TNF-α可溶性受体构建体依那西普对角叉菜胶诱导的胸膜炎的影响。依那西普治疗（在注射角叉菜胶前2小时皮下注射5 mg/kg）显著降低了角叉菜胶诱导的胸膜炎的实验室和组织学指标。我们的结果表明，给予依那西普与缺失TNF-αR1受体产生的结果相同，这为TNF-α作为治疗应用的优秀靶点提供了新的见解。
