半乳糖凝集素-3基因敲除对MRSA感染小鼠皮肤模型中脓肿发展的影响  

Effect of galectin-3 gene knockout on abscess development in methicillin-resistant Staphylococcus aureus-infected mouse skin model

作　　者：王淑君 张丁[1] 李一鸣 张思怡 周静[1] 陈紫涵 程美琦 韩珊珊 王德成 晁金 WANG Shujun;ZHANG Ding;LI Yiming;ZHANG Siyi;ZHOU Jing;CHEN Zihan;CHENG Meiqi;HAN Shanshan;WANG Decheng;CHAO Jin(Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy,College of Basic Medical Sciences,ChinaThree Gorges University,Yichang Key Laboratory of Infection and Inflammation,Yichang 443002,China)

机构地区：[1]三峡大学肿瘤微环境与免疫治疗湖北省重点实验室,三峡大学基础医学院,宜昌市感染与炎症损伤重点实验室,湖北宜昌443002

出　　处：《中国实验动物学报》2024年第8期992-1000,共9页Acta Laboratorium Animalis Scientia Sinica

基　　金：湖北省自然科学基金(2023AFB736);肿瘤微环境与免疫治疗湖北省重点实验室开放课题(2023KZL027)。

摘　　要：目的探讨半乳糖凝集素-3(galectin-3,Gal3)在耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)感染小鼠皮肤模型中对皮肤脓肿发展以及肥大细胞(mast cell,MC)激活的影响。方法将6~8周龄的野生型小鼠和Gal3基因敲除(Gal3^(-/-))小鼠分为4组:野生型小鼠+PBS组、野生型小鼠+MRSA组、Gal3^(-/-)小鼠+PBS组、Gal3^(-/-)小鼠+MRSA组,分别皮下注射MRSA或PBS,每组5只。观察记录小鼠皮肤脓肿发展和病理学变化,比较皮肤组织中的载菌量,并分析相关炎性细胞因子、MC脱颗粒及活化标志物5-羟色胺(5-hydroxy tryptamine,5-HT)的差异。结果感染MRSA后,野生型小鼠皮肤出现渐进性脓肿,而Gal3^(-/-)小鼠脓肿体积较小。与野生型小鼠+MRSA组相比,Gal3^(-/-)小鼠+MRSA组皮肤载菌量显著降低(P<0.01),且组织病理学观察显示较少的炎症细胞浸润。Gal3^(-/-)小鼠皮肤中的细胞因子IL-1β、TNF-α、IL-33、TGF-β和IL-10均显著低于野生型小鼠(P<0.05)。甲苯胺蓝染色显示,野生型小鼠+MRSA组皮肤组织中大量MC释放颗粒物质,而Gal3^(-/-)小鼠+MRSA组仅发现少量脱颗粒的MC。免疫组化染色进一步发现,Gal3^(-/-)小鼠+MRSA组中5-HT的表达显著低于野生型小鼠+MRSA组。结论Gal3缺失降低MRSA感染导致的小鼠皮肤中MC的活化与脱颗粒,改变炎症反应,减轻了皮肤组织的脓肿发生。Objective To investigate the effects of galectin-3(Gal3)on skin abscess development and activation of mast cells(MC)in mice infected with methicillin-resistant Staphylococcus aureus(MRSA).Methods Wild type mice and Gal3-knockout(Gal3^(-/-))mice,at 6~8 weeks of age,were divided into four groups:Wild type mice+PBS group,Wild type mice+MRSA group,Gal3^(-/-)mice+PBS group,Gal3^(-/-)mice+MRSA group,were subcutaneously injected with MRSA or the same volume of phosphate buffer saline,with five mice per group.The development and pathological changes of skin abscess were monitored and recorded.The bacterial load in skin tissues was compared,and the expression of associated cytokines,degranulation of MC,and the distribution of MC activation marker 5-hydroxytryptamine(5-HT)were detected.Results The skin of Wild type mice showed progressive abscesses after subcutaneous infection with MRSA,but the Gal3^(-/-)mice showed smaller abscess areas.Compared to the Wild type mice+MRSA group,the Gal3^(-/-)mice+MRSA group showed lower bacterial loading in the skin tissues(P<0.01)and fewer infiltrating inflammatory cells with histopathological observation.The expression of cytokines,including IL-1β,TNF-α,IL-33,TGF-β,and IL-10,were significantly lower in Gal3^(-/-)mice than Wild type mice(P<0.05).The toluidine blue staining showed a large number of degranulated MCs in the skin tissues of the wild type mice+MRSA group,whereas only a few degranulated MCs were observed in the Gal3^(-/-)mice+MRSA group.It was further found that the expression of 5-HT in Gal3^(-/-)mice+MRSA group was significantly lower than that in wild-type mice+MRSA group with immunohistochemical staining.Conclusion Gal3 deficiency reduced the activation and degranulation of mouse skin MC after MRSA infection,resulting in changes to inflammatory responses and alleviating the severity of skin tissue abscesses.

关 键 词：耐甲氧西林金黄色葡萄球菌 半乳糖凝集素-3 基因敲除 肥大细胞 活化 

分 类 号：Q95-33[生物学—动物学]