黏附分子CD44在实验性自身免疫性脑脊髓炎中的作用

Role of the adhesion molecule CD44 in experimental autoimmune encephalomyelitis

摘要:

目的 探讨黏附分子CD44在实验性自身免疫性脑脊髓炎（EAE）发病中的作用。方法 将20只大鼠随机分为正常对照组及EAE组，EAE组采用粗制髓鞘碱性蛋白（MBP）抗原注入大鼠后足掌皮下（0.2 ml/100 g）制作EAE模型，观察大鼠的发病情况及病理表现；并采用免疫组织化学法检测两组大鼠脑组织CD44的含量。结果 正常对照组大鼠未发病，EAE组大鼠均有不同程度的发病。HE染色后，光镜下观察，正常对照组大鼠脑和脊髓无异常；EAE组大鼠可见脑及脊髓实质内小血管充血，小静脉周围有大量炎性细胞浸润，血管周围白质脱髓鞘改变。免疫组化显示，正常对照组大鼠脑和脊髓组织未发现CD44阳性细胞；EAE组大鼠中枢神经系统（CNS）白质及灰白质交界处可见大量CD44阳性细胞。结论 EAE模型中存在黏附分子CD44的高表达，其对EAE的发病可能起到促进作用。

Abstract:

Objective To investigate the role of the adhesion molecule CD44 in the pathogenesis of experimental autoimmune encephalomyelitis (EAE).Methods A total of 20 rats were randomly divided into EAE group and control group. Crude myelin basic protein (MBP) antigen (0.2 mL/100 g) was subcutaneously injected into the hind foot of the rats in the EAE group to establish an EAE model, and then disease onset and pathological manifestations were observed. Immunohistochemistry was used to measure the content of CD44 in brain tissue for both groups.Results Disease onset was not observed in the control group, while this was observed in the EAE group with varying degrees. Observation under a light microscope after HE staining showed no abnormalities in the brain and spine of the rats in the control group, while congestion of small blood vessels, inflammatory cell infiltration around small veins, and demyelination in white matter were observed in the EAE group. Immunohistochemistry showed that no CD44-positive cells were found in the brain and spinal tissues of the rats in the control group, while a large number of CD44-positive cells were observed at the junction of grey matter and white matter in the central nervous system.Conclusions There is high expression of the adhesion molecule CD44 in the rat model of EAE, which may promote the onset of EAE.