Aitken M L, Villalon M, Pier M, Verdugo P, Nameroff M
Department of Medicine, University of Washington, Seattle 98195.
Am J Respir Cell Mol Biol. 1993 Jul;9(1):26-32. doi: 10.1165/ajrcmb/9.1.26.
Although morphologic features have been used to follow cell lineage and differentiation, an objective assessment of differentiation can be best established by characterizing the expression of specific proteins that form the phenotypic profile of differentiated cells. Thus, specific markers or probes are required to unequivocally identify the various types of cells resulting from differentiation in a cell lineage. We report characterization of an IgM monoclonal antibody (5B4/H3), which recognized a surface antigen of approximately 130 kD unique to ciliated cells. The antibody reacted with the lumenal surface of the ciliated cells in transmission electron micrographs, in immunohistochemical staining of tracheal sections, and in cultured monolayers of tracheal epithelial cells. Flow cytometry, performed on enzymatically dispersed tracheal epithelial cells tagged with 5B4/H3 and fluorescent-labeled goat anti-mouse IgA/IgG/IgM, produced a population of fluorescent ciliated cells and a mixed nonfluorescent, nonciliated cell population. Ciliated cells were followed in vitro by time-lapse video microscopy for 48 to 72 h. Some of the ciliated cells lost their cilia under these culture conditions, but these cells were still found to react with the 5B4/H3 antibody. The antigen detected by this antibody remained on the surface of the cells after they lost their cilia. These results indicate that 5B4/H3 recognized a cell surface antigen that is specific to the ciliated cells and is independent of cell morphology. This marker will be useful in tissue culture studies of airway epithelial lineage, or differentiation, in which cell morphology is variable and cannot be used as a reliable marker of differentiation.
尽管形态学特征已被用于追踪细胞谱系和分化，但通过表征构成分化细胞表型特征的特定蛋白质的表达，能够最好地建立对分化的客观评估。因此，需要特定的标志物或探针来明确识别细胞谱系中分化产生的各种类型的细胞。我们报告了一种IgM单克隆抗体（5B4/H3）的特性，该抗体识别一种约130 kD的纤毛细胞特有的表面抗原。在透射电子显微镜下，该抗体与纤毛细胞的管腔表面反应，在气管切片的免疫组织化学染色中以及在气管上皮细胞的培养单层中也有反应。对用5B4/H3和荧光标记的山羊抗小鼠IgA/IgG/IgM标记的酶分散气管上皮细胞进行流式细胞术，产生了一群荧光纤毛细胞和一群混合的非荧光、非纤毛细胞。通过延时视频显微镜在体外对纤毛细胞进行了48至72小时的追踪。在这些培养条件下，一些纤毛细胞失去了它们的纤毛，但这些细胞仍被发现与5B4/H3抗体反应。这些细胞失去纤毛后，该抗体检测到的抗原仍留在细胞表面。这些结果表明，5B4/H3识别一种纤毛细胞特有的细胞表面抗原，且该抗原与细胞形态无关。这种标志物将有助于气道上皮谱系或分化的组织培养研究，在这些研究中细胞形态是可变的，不能用作可靠的分化标志物。
