Dráberová E, Lukás Z, Ivanyi D, Viklický V, Dráber P
Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague.
Histochem Cell Biol. 1998 Mar;109(3):231-9. doi: 10.1007/s004180050222.
The class III beta-tubulin isotype is widely used as a neuronal marker in normal and neoplastic tissues. This isotype was, however, also immunodetected in certain tumours of non-neuronal origin such as squamous cell carcinoma. Using a newly described monoclonal antibody we compared the distribution of class III beta-tubulin in normal and neoplastic tissues. The TU-20 mouse monoclonal antibody was prepared against a conserved synthetic peptide from the C-terminus of the human class III beta-tubulin isotype, and its specificity was confirmed by immunoblotting, by competitive enzyme-linked immunosorbent assay and by immunofluorescence microscopy on cultured cells. In different cell lines of various origins the antibody reacted only with neuroblastoma Neuro-2a cells and with embryonal carcinoma P19 cells stimulated to neuronal differentiation by retinoic acid. Immunohistochemistry on formaldehyde-fixed paraffin-embedded normal human tissues revealed the presence of the class III beta-tubulin isotype in cell bodies and processes of neuronal cells in the peripheral and central nervous systems. In other tissues, this beta-tubulin isotype was not immunodetected. Class III beta-tubulin was found in all cases of ganglioneuroblastoma, ganglioneuroma, medulloblastoma, neuroblastoma, sympathoblastoma and in one case of teratoma. In contrast, no reactivity was detected in tumours of non-neuronal origin, including 32 cases of squamous cell carcinoma. The results indicate a specific TU-20 epitope expression exclusively in neuronal tissues. The antibody could thus be a useful tool for the probing of class III beta-tubulin functions in neurons as well as for immunohistochemical characterisation of tumours of neuronal origin.
III类β-微管蛋白同型在正常组织和肿瘤组织中被广泛用作神经元标记物。然而，在某些非神经源性肿瘤如鳞状细胞癌中也检测到了这种同型。我们使用一种新描述的单克隆抗体比较了III类β-微管蛋白在正常组织和肿瘤组织中的分布。TU-20小鼠单克隆抗体是针对人III类β-微管蛋白同型C末端的一个保守合成肽制备的，其特异性通过免疫印迹、竞争性酶联免疫吸附测定以及对培养细胞的免疫荧光显微镜检查得以证实。在各种来源的不同细胞系中，该抗体仅与神经母细胞瘤Neuro-2a细胞以及经视黄酸刺激向神经元分化的胚胎癌P19细胞发生反应。对甲醛固定石蜡包埋的正常人体组织进行免疫组织化学分析显示，III类β-微管蛋白同型存在于外周和中枢神经系统神经元细胞的胞体和突起中。在其他组织中，未检测到这种β-微管蛋白同型。在所有神经节神经母细胞瘤、神经节神经瘤、髓母细胞瘤、神经母细胞瘤、交感神经母细胞瘤病例以及一例畸胎瘤中均发现了III类β-微管蛋白。相比之下，在包括32例鳞状细胞癌在内的非神经源性肿瘤中未检测到反应性。结果表明存在仅在神经元组织中表达的特定TU-20表位。因此，该抗体可能是探究III类β-微管蛋白在神经元中的功能以及对神经源性肿瘤进行免疫组织化学特征分析的有用工具。
