Li J L, Shen G L, Ghetie M A, May R D, Till M, Ghetie V, Uhr J W, Janossy G, Thorpe P E, Amlot P
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas 75235.
Cell Immunol. 1989 Jan;118(1):85-99. doi: 10.1016/0008-8749(89)90359-6.
The CD22 antigen is expressed on the surface of normal human B cells and some neoplastic B cell lines and tumors. Previous cross-blocking studies using a panel of monoclonal anti-CD22 antibodies have defined four epitope groups, termed A-D. In the present studies, we have further dissected the epitopes recognized by four monoclonal anti-CD22 antibodies using immunoprecipitation and cross-blocking techniques, immunofluorescence analyses with a variety of cell lines, and immunoperoxidase analyses of 36 normal human tissues. Two of the antibodies, HD6 and RFB4, have been described previously, and two, UV22-1 and UV22-2, are described in this report. Our studies indicate that the four monoclonal antibodies show unexpected complexities in their reactivity with CD22+ and CD22- cells and their reactivity with solubilized CD22 molecules. The four antibodies, which recognize epitopes defined previously as CD22-A and CD22-B, further subdivide these epitope clusters into four determinants, A1, A2, B1, and B2. Furthermore, only two of the antibodies, RFB4 and UV22-2, are B cell-specific. In summary, our data indicate that RFB4 and UV22-2 would be the antibodies of choice for constructing immunotoxins to treat B cell tumors.
CD22抗原表达于正常人B细胞以及一些肿瘤性B细胞系和肿瘤的表面。先前使用一组抗CD22单克隆抗体进行的交叉阻断研究确定了四个表位组，称为A - D。在本研究中，我们使用免疫沉淀和交叉阻断技术、对多种细胞系进行免疫荧光分析以及对36例正常人体组织进行免疫过氧化物酶分析，进一步剖析了四种抗CD22单克隆抗体识别的表位。其中两种抗体HD6和RFB4先前已有描述，另外两种抗体UV22 - 1和UV22 - 2在本报告中进行描述。我们的研究表明，这四种单克隆抗体在与CD22 +和CD22 -细胞的反应性以及与可溶性CD22分子的反应性方面表现出意想不到的复杂性。这四种识别先前定义为CD22 - A和CD22 - B表位的抗体，进一步将这些表位簇细分为四个决定簇，即A1、A2、B1和B2。此外，只有两种抗体RFB4和UV22 - 2是B细胞特异性的。总之，我们的数据表明，RFB4和UV22 - 2将是构建用于治疗B细胞肿瘤的免疫毒素的首选抗体。
