Wood G S, Freudenthal P S, Edinger A, Steinman R M, Warnke R A
Department of Dermatology, Case Western Reserve University, Cleveland, Ohio.
Am J Pathol. 1991 Jun;138(6):1451-9.
The authors studied the pattern of leukocyte common antigen (CD45) epitope expression on dendritic cells in sections of human epidermis, tonsillar epithelium, dermatopathic lymph nodes, and in isolates from blood. The monoclonal antibodies (MAb) used were specific for all known CD45 epitopes, including the seven different CD45 common epitopes as well as the four known CD45R epitopes (two CD45RA, one CD45RB, and one CD45RO). Dendritic cells in all sites were uniformly reactive for the CD45 common epitopes tested except 2B11, which may recognize a CD45R rather than CD45 epitope. By single-label immunoperoxidase and double-label immunofluorescence epitope mapping of CD1a+ dendritic cells in tissue sections, it was generally difficult or impossible to detect expression of CD45RA, CD45RB, CD45RO, or 2B11. In blood dendritic cells, however, low levels of these CD45R epitopes were detected consistently using single-label immunoperoxidase staining of cytocentrifuge preparations. Monocytes were similar to blood dendritic cells except that the staining with MAb to CD45RO and 2B11 was slightly stronger. The authors conclude that dendritic cells differ from most subpopulations of lymphocytes in that CD45 common epitopes are readily detectable but the existing RA, RB, and RO epitopes are either undetectable or expressed at relatively low levels. These studies raise the possibility that CD1a+ dendritic cells may express a novel dominant CD45 isoform.
作者研究了人类表皮、扁桃体上皮、皮肤性淋巴结切片以及血液分离物中树突状细胞上白细胞共同抗原（CD45）表位的表达模式。所使用的单克隆抗体（MAb）对所有已知的CD45表位具有特异性，包括七种不同的CD45共同表位以及四种已知的CD45R表位（两种CD45RA、一种CD45RB和一种CD45RO）。除2B11外，所有部位的树突状细胞对所检测的CD45共同表位均呈一致反应，2B11可能识别的是CD45R而非CD45表位。通过对组织切片中CD1a +树突状细胞进行单标记免疫过氧化物酶和双标记免疫荧光表位定位，通常很难或无法检测到CD45RA、CD45RB、CD45RO或2B11的表达。然而，在血液树突状细胞中，使用细胞离心涂片的单标记免疫过氧化物酶染色始终能检测到这些CD45R表位的低水平表达。单核细胞与血液树突状细胞相似，只是用MAb对CD45RO和2B11的染色略强。作者得出结论，树突状细胞与大多数淋巴细胞亚群不同，在于CD45共同表位易于检测，但现有的RA、RB和RO表位要么无法检测到，要么以相对较低的水平表达。这些研究提出了CD1a +树突状细胞可能表达一种新的优势CD45异构体的可能性。
