Immunogenotypic and Viral Analyzes of Lethal Midline Granuloma

所谓的致命性中线肉芽肿具有很高的临床和理论价值。致死性中线肉芽肿的病因尚不清楚，发病机制多种多样，关于确切的分类和自然病史也存在争议。在这项研究中，我们报告了11例致死性中线肉芽肿的免疫病理、免疫表型和病毒特征。他们的活检标本的组织病理学诊断最初是多形性网织或中线恶性网织。免疫组织化学结果显示，未成熟或异型细胞中有9例T细胞表型为CD2、CD3、CD4、CD8，2例为自然杀伤细胞表型CD2、CD56。这些细胞也被发现为HLA-DR阳性，这表明它们是激活的细胞。然而，T细胞的免疫组织学不能给出类似的克隆性线索，因为在B细胞肿瘤中，通过免疫表型轻链可以给出类似的线索。T-…基因探针的建立更多的细胞受体基因，有可能分析起源于淋巴细胞的肿瘤的谱系和克隆性。Southern杂交7例，5例TCR基因、TCRbeta或TCRGamma链重排，未见免疫球蛋白重链重排。这些发现为大多数致死性中线肉芽肿中的单克隆性T细胞增殖提供了确凿证据。此外，表型和免疫表型分析显示，一些疾病起源于自然杀伤细胞谱系。采用Southern杂交和体外杂交技术检测鼻部肿瘤活检标本中EB病毒DNA，并用双色免疫荧光法同时检测EB病毒核抗原(EBNA)和T细胞表面标志。进一步的免疫荧光和Northern印迹显示EBNA2基因和潜伏膜蛋白基因在鼻腔肿瘤细胞中均有表达。这些患者具有较高的EBV抗体滴度。这些发现表明致死性中线肉芽肿与EBV有因果关系。根据免疫分型和病毒研究，组织学诊断为多形性网织/中线恶性网状增生症的致死性中线肉芽肿被证明是一种EB病毒相关性T细胞增生性疾病。较少

So-called lethal midline granuloma is of great clinical and theoretical interest. The etiology of lethal midline granuloma is unknown and the pathogenesis is variable, with debate as to precise classification and natural history. In this study, we reported immunopathological, immunogenotypic and viral features in 11 cases of lethal midline granuloma. The histopathological diagnosis of their biopsy specimens was initially polymorphic reticulosis or midline malignant reticulosis. Immunohistologic study of the specimens revealed that immature or atypical cells had phenotypes of T-cells, CD2, CD3, CD4, CD8 in 9 cases and of natural killer cells, CD2 and CD56 in other 2 cases. Those cells were also found to be positive for HLA-DR,which indicated that they were activated cells. Immunohistology in T-cells, however, was not able to give a similar clue to clonarity as it was possible within B-cells neoplasms by immunophenotyping the light chains. With the establishment of cDNA probes for the T- … More cell receptor genes it was possible to analyze neoplasms of lymphocyte origin for lineage and clonality. The Southern blot analysis of 7 cases showed rearrangement of TCR gene, TCRbeta or TCRgamma chain in 5 cases, whereas none of them showed rearragement of immunoglobulin heavy chain. These findings represented conclusive evidence for a monoclonal T-cell proliferation within the majority of lethal midline granuloma. In addition, phenotypic and immunogenotypic analyzes revealed that some of the disease originated in natural killer cell lineage. EpsteinBarr virus (EBV) DNA was detected in the nasal tumour biopsy specimens by Southern blotting and in vitro hybridisation with simultaneous detection of EBV determined nuclear antigen (EBNA) and T cell surface markers by two color immunofluorescence. Further immuno-fluorescence and northern blotting revealed that EBNA2 gene and also latent membrane protein gene were expressed in the nasal tumour cells. The patients had high titres of antibodies to EBV.These findings suggest that lethal midline granuloma is causally associated with EBV.On the ground of immungenotypi and viral studies, lethal midline granuloma histologically diagnosed as polymorphic reticulosis/midline malignant reticulosis are proven to be a Epstein-Barr virus associated T-cell lymphoproliferative disorder. Less