中国恒河猴SHIVKU-1艾滋病模型中枢神经系统的病理研究

Pathological study of central nervous system injury in a Chinese rhesus macaque model of SHIVKU-1 infection

目的建立中国恒河猴SHIVKU-1艾滋病模型,观察感染SHIVKU-1的中国恒河猴中枢神经系统损伤的病理改变特点。方法用SHIVKU-1感染2只中国恒河猴(编号WSH01和WSH02),分别于感染后第72周和第70周出现严重艾滋病症状时执行安乐死。取脑组织的不同部位行常规病理切片,进行HE染色检查和免疫组织化学染色检查。结果 WSH01恒河猴感染晚期出现站立困难、行动迟缓、左半身控制能力丧失等明显的神经艾滋临床症状。WSH02恒河猴感染晚期全身耗竭,严重腹泻。HE染色检查WSH01恒河猴小脑、脑干、枕叶中可见多核巨细胞浸润和神经胶质小结形成;大脑皮层小胶质细胞增生;海马回神经元细胞减少、排列无序。病理诊断为艾滋病脑炎。WSH02猴仅在脑组织中观察到部分小胶质细胞结节,未见其他明显的神经病理损伤。免疫组化检查观察到在实验猴脑组织有两种主要的损伤形式,分别为典型的血管周病变和弥散性病变;大量活化巨噬细胞和小胶质细胞浸润和激活,多核巨细胞形成(CD68,CD163,Iba-1);损伤部位SHIVKU-1病毒蛋白P28强阳性(SIV p28);WSH01恒河猴海马回神经元细胞明显减少且排列无序(MAP2)。结论中国恒河猴SHIVKU-1感染导致中枢神经系统损伤,脑组织各部位表现出不同程度的病理改变,以大量巨噬细胞/小胶质细胞浸润、激活,并伴有病毒显著增殖为主。

Objectives To create a Chinese rhesus macaque model of SHIVKU-1 infection and to observe pathological changes during central nervous system injury in Chinese rhesus macaques infected with SHIVKU-1.Methods Two Chinese rhesus macaques(WSH01 and WSH02)were infected with SHIVKU-1 and euthanized 72 weeks and 70 weeks after infection,respectively,when severe AIDS symptoms occurred.After euthanasia,different parts of brain tissues were excised and embedded in paraffin.Sections with a thickness of 4ìm were then cut and subjected to HE staining.Immunohistochemical staining was performed with the macrophage/monocyte markers(CD68,CD163,Iba-1),SIV gag protein(SIV p28),and a neuron maker(MAP2)to analyze the immunophenotype of histological sections.Results Significant neuroAIDS symptoms were observed in the late stage of infection of rhesus macaque WSH01,such as difficulty standing,slowness of movement,and loss of control of the left half of the body.Rhesus macaque WSH02 exhibited systemic exhaustion and severe diarrhea in the late stage of infection.HE staining indicated infiltration of multinucleated giant cells in the cerebellum,brainstem,and occipital lobe of rhesus macaque WSH01,and glial nodules appeared in the perivascular area;microglia proliferation in the cerebral cortex and neurons in the hippocampal gyrus was markedly reduced,and microglia were randomly arranged.The pathological diagnosis is AIDS encephalitis.However,only a few microglial nodules were observed in the brain tissue of rhesus macaque WSH02,and there were no other obvious neuropathological lesions.Immunohistochemical staining indicated that there were two main forms of damage in the brain tissue of Chinese rhesus macaques infected with SHIVKU-1,which were typical perivascular lesions and diffuse lesions.CD68,CD163,and Iba-1 staining indicated infiltration and activation of a large number of activated macrophages and microglia,and formation of multinucleated giant cells;SIV p28 staining indicated strong positivity for the SHIVKU-1 virus protein at the injury site;and MAP2 staining indicated that neurons were significantly reduced and disordered in the hippocampus of WSH01.Conclusion SHIVKU-1 infection can lead to central nervous system injury in Chinese rhesus macaques,and different degrees of pathological damage appeared in various parts of brain tissues of these macaques.The main pathological features wre the infiltration and activation of a large number of macrophages/microglia and significant proliferation of the virus.