N-甲基亚硝基脲诱导胸腺淋巴瘤病理形态学及超微结构研究

Pathological Features and Ultrastructure of N-methyl-N-nitrosourea(MNU)-induced Thymic Lymphomas in Mice

本研究探讨N-甲基亚硝基脲(MNU)诱导的小鼠胸腺淋巴瘤的肿瘤细胞起源及分型。应用光学显微镜、透射电子显微镜和免疫组织化学方法,对诱发肿瘤进行观察。结果表明,光学显微镜下胸腺结构破坏,代之以弥漫分布的中等大小的淋巴样肿瘤细胞。免疫组织化学检测显示,瘤细胞表达CD3和TdT。超微结构观察显示,瘤细胞表面无突起,核形相对规则或伴有扭曲核,胞质内细胞器极少。结论:MNU诱导的所有肿瘤为胸腺T淋巴母细胞淋巴瘤。

The objective of study was to investigate the origin and to classify the subtype of N-methyl-N-nitrosourea （MNU）-induced thymic lymphomas in mice. Histopathologic, immunohistochemical and ultrastructural studies were performed to analyze the pathological features of the neoplasms. The results showed that the thymus in all cases became totally replaced by sheets of cells of the lymphoid series. All the tumors coexpressed CD3 and TdT. Transmission electron microscopic study showed the plasma membranes of malignant lymphoma cells were smooth. The nuclear profiles were usually regular, with varying percentage of convoluted nuclei. Few cell organoids were observed in cytoplasm. In conclusion, all the MNU-induced tumor classified by histopathologic, immunohistochemical and ultrastructural studies as precursor lymphoblastic lymphoma that were unquestionably related to the thymus origin and T-cell lineage.