A NOVEL MARKER OF MURINE BONE-MARROW HEMATOPOIETIC STEM-CELLS THAT IS EXPRESSED ON PERIPHERAL T-CELLS AND IS ASSOCIATED WITH A FUNCTIONALLY IMPORTANT MOLECULE ON ACTIVATED CYTOTOXIC T-LYMPHOCYTES
A NOVEL MARKER OF MURINE BONE-MARROW HEMATOPOIETIC STEM-CELLS THAT IS EXPRESSED ON PERIPHERAL T-CELLS AND IS ASSOCIATED WITH A FUNCTIONALLY IMPORTANT MOLECULE ON ACTIVATED CYTOTOXIC T-LYMPHOCYTES
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DOI：
10.1089/hyb.1994.13.353
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发表时间：
1994-10-01
期刊：
影响因子：
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通讯作者：
KLEIN, JR
中科院分区：
文献类型：
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作者：
MOSLEY, RL;HAMAD, M;KLEIN, JR
已分离到一株单抗(R2/60)，它定义了一种新的小鼠T细胞淋巴细胞标志物。由单抗R2/60识别的决定簇存在于骨髓(BM)造血干细胞的一个亚群、成人胸腺细胞、外周T细胞(静息和激活)和小鼠T细胞肿瘤系上，尽管它在成熟的B细胞上不表达。在使用放射性标记的成人胸腺细胞膜裂解物的免疫沉淀研究中，单抗R2/60沉淀了一个44 kDa的膜结合二聚体。在功能上，单抗R2/60通过激活的CTL和连接到Fc受体的靶细胞上的CTL克隆介导非抗原依赖的细胞裂解；然而，在细胞毒试验之前与效应细胞结合并不抑制CTL的靶细胞裂解，这表明R2/60决定簇参与了已经激活的CTL的跨膜信号传递，但它不参与靶细胞的黏附或抗原识别。此外，在没有额外刺激的情况下，用单抗R2/60直接刺激T细胞并不能诱导细胞增殖，这进一步意味着R2/60决定簇在功能上参与了T细胞反应的效应器而不是诱导阶段。
A MAb (R2/60) has been isolated that defines a novel lymphocyte marker of murine T cells. The determinant recognized by MAb R2/60 is present on a subset of bone marrow (BM) hematopoietic stem cells, on adult thymocytes, on peripheral T cells (both resting and activated), and on murine T cell tumor lines, although it is not expressed on mature B cells. In immunoprecipitation studies using radiolabeled membrane lysates from adult thymocytes, MAb R2/60 precipitated a 44-kDa membrane-bound dimer. Functionally, MAb R2/60 mediated antigen-independent cell lysis by activated CTLs, and by CTL clones, when bridged to Fc receptor-bearing target cells; however, binding of MAb R2/60 to effector cells prior to cytotoxic assays did not inhibit target cell lysis by CTLs, suggesting that the R2/60 determinant is involved in transmembrane signaling to already activated CTLs, but that it is not involved in target cell adhesion or antigen recognition. Moreover, direct stimulation of T cells by MAb R2/60 in the absence of additional stimuli did not induce cell proliferation, further implying that the R2/60 determinant is functionally involved in the effector rather than the inductive phase of the T cell response.