胶原诱导性关节炎大鼠滑膜巨噬细胞磁共振成像的初步研究  

Magnetic resonance imaging of synovial macrophages in rat collagen-induced arthritis

作　　者：顾娟芳[1] 王美美[1] 张芹[1] 王琦[1] 

机构地区：[1]东南大学附属中大医院风湿免疫科,南京210009

出　　处：《中华风湿病学杂志》2013年第2期80-85,I0001,共7页Chinese Journal of Rheumatology

基　　金：江苏省自然科学基金（BK2009276）

摘　　要：目的初步探讨胶原诱导性关节炎（CIA）大鼠关节滑膜巨噬细胞磁共振成像（MRt）的可行性。方法通过鸡Ⅱ型胶原与完全弗氏佐剂乳化构建CIA模型，造模成功大鼠随机分为3组：模型早、中、晚期组，分别于免疫第14、28、42天静脉注射超微超顺磁性氧化铁（USPIO），注射前及注射后24h分别在7．0T小动物磁共振扫描仪上行膝关节T1WI，T2WI和T2＊WI序列磁共振扫描。各组大鼠于第2次磁共振扫描完成后处死，留取膝关节滑膜制成病理组织切片，行常规苏木素．伊红（HE）染色、普鲁士蓝染色和CD68免疫组织化学染色。统计学处理采用单因素方差分析，进一步两两比较采用LSD．t检验。结果磁共振平扫模型早、中、晚期组大鼠膝关节可见不同程度滑膜增厚，关节积液。USPIO增强T1WI各模型组大鼠膝关节滑膜未见明显信号改变；USPIO增强T2WI、T2＊WI各模型组大鼠膝关节滑膜可见信号不均匀降低，滑膜信噪比（sNR）和滑膜／肌肉对比噪声~L（CNR）增强前后比较差异有统计学意义（P〈0．05）。正常对照组大鼠膝关节磁共振平扫及USPIO增强未见明显滑膜增厚及信号改变。病理组织学证实铁颗粒分布于炎症滑膜巨噬细胞内。结论借助特异性对比剂USPIO，大鼠CIA关节滑膜巨噬细胞MRI是可行的，且早期即可反映关节滑膜巨噬细胞浸润，可望为类风湿关节炎早期诊断提供新的思路。Objective To prospectively evaluate the ability of 7.0 T magnetic resonance （MR） imaging enhanced with ultrasmall superparamagnetic iron oxide （USPIO） particles in detecting synovial macrophages in a rat model of collagen-induced arthritis （CIA）. Methods CIA was induced by subcutaneous injection of chicken type II collagen. Arthritis rats were randomly divided into early, middle and late model group. Other rats served as controls. Knees of rats were imaged by a 7.0 T MR imager before and 24 hours after USPIO intravenous administration （200 I^mol Fe/kg） on Day 14, 28, 42, respectively. The MR imaging protocol included Tl-weighted （T1W） spin-echo （SE） sequences, T2-weighted （T2W） SE sequences, T2 ＊ W gradient- echo （GRE） sequences. After the completion of MR imaging, rats were sacrificed to obtain histopathologic samples of synovial membrane and staining. LSD-t test and one-way ANOVA were used for statistical analysis. Results Knees of arthritis rats in early, middle and late model groups developed synovial thickening and joint effusion on images from all sequences, whereas not developed in the control group. On USPIO-enhanced images, synovial tissue of arthritis knees showed slight to distinct signal intensity loss on post contrast T2WI and T2WI. However, no signal intensity enhancement of inflamed synovium was observed on postcont^ast T1WI. Meanwhile, no control knees developed any visually detectable changes between pre- and postcontrast images. The quantitative analyses were coincident with the visual differences in signal changes between pre- and postcontrast images. Histologic examination confirmed uptake of iron in the macrophages of arthritic knees. Conclusion USPIO enhanced 7.0 T MR imaging can detect synovial maerophages in different period of CIA, which may be an additional tool for early and accurate diagnosis of RA.

关 键 词：关节炎 实验性 巨噬细胞 磁共振成像 超微超顺磁性氧化铁颗粒 

分 类 号：R593.22[医药卫生—内科学]