Jung L K, Fu S M
Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City 73104.
J Immunol Methods. 1989 Jan 6;116(1):137-44. doi: 10.1016/0022-1759(89)90322-0.
CD7 is a T differentiation antigen which is useful in the identification of precursor T cells as well as an important marker for the identification of leukemic T cells. It has proved to be useful as a target for immunotherapy by immunotoxins in several clinical settings. Most monoclonal antibodies to this antigen bind to the same or similar epitope. We have produced a monoclonal antibody, 69, which identifies a different epitope as that of the prototypic mAb to CD7, 3A1. Using mAB 69, we have devised a sandwich CD7-ELISA to detect solubilized CD7 antigen, with mAb 69 in the solid phase as the capturing mAb. This assay is sensitive and is able to detect antigen present on 2-5 x 10(4) activated T cells. This assay has been used to study the fate of CD7 on the membrane and in the cytosol of T cells during the process of mitogenesis. We have also utilized this assay to demonstrate the presence of free CD7 antigen in culture supernatant of activated T cells. This method will be useful to analyze antigen recovery from bulk cell cultures or from molecularly engineered microbial organisms. In addition, the sandwich CD7-ELISA may prove useful in monitoring the effects of immunotherapy in patients with leukemia.
CD7是一种T细胞分化抗原，可用于鉴定前体T细胞，也是鉴定白血病T细胞的重要标志物。在几种临床环境中，它已被证明可作为免疫毒素免疫治疗的靶点。大多数针对该抗原的单克隆抗体与相同或相似的表位结合。我们制备了一种单克隆抗体69，它识别的表位与CD7原型单克隆抗体3A1不同。使用单克隆抗体69，我们设计了一种夹心CD7-ELISA来检测可溶性CD7抗原，以固相中的单克隆抗体69作为捕获单克隆抗体。该检测方法灵敏，能够检测出存在于2-5×10⁴个活化T细胞上的抗原。该检测方法已用于研究有丝分裂过程中T细胞膜和细胞质中CD7的命运。我们还利用该检测方法证明了活化T细胞培养上清液中存在游离的CD7抗原。该方法将有助于分析从大量细胞培养物或分子工程微生物中回收的抗原。此外，夹心CD7-ELISA可能在监测白血病患者免疫治疗效果方面有用。
