Wang Jiamin, Li Fang, Zhang Guangbo, Chen Yongjin, Hu Yumin, Chen Xuqin, Lu Binfeng, Zhang Xueguang
Institute of Biotechnology and Clinical Immunology Research Laboratory of Jiangsu Province, Soochow University, Suzhou, China.
Hybridoma (Larchmt). 2010 Jun;29(3):241-9. doi: 10.1089/hyb.2009.0113.
Human AC133 antigen, also called CD133, is a unique transmembrane glycoprotein encoded by the PROM1 gene. It was initially suggested as a cell surface marker for hematopoietic stem/progenitor cells and has also been identified recently as a cancer stem cell marker in brain, colorectal, and prostate cancers. AC133 has two isoforms, one is AC133-1 and the other is AC133-2. Whether the two isoforms are functionally redundant or serve distinct functions remains unclear. In order to further explore the physiological and pathological functions of CD133-2, we generated two mouse antihuman CD133-2 monoclonal antibodies (clones 6B3 and 9G4). Then, we carefully characterized the biological functions of these monoclonal antibodies (MAbs) and showed that 6B3 and 9G4 bound to two epitopes of CD133, which are different from that recognized by the commercially available anti-CD133 MAb (AC141). These two MAbs could be used in cell immunostaining, Western blot, and immunohistochemical staining. We have further shown that MAb 6B3 enhances the growth of human myelogenous leukemic cell line U937 and human colon adenocarcinoma cell line SW480, suggesting a functional role of CD133 in these cells. Taken together as a useful tool, these two antibodies might be of great value for further exploration of the expression and function of CD133.
人AC133抗原，也称为CD133，是一种由PROM1基因编码的独特跨膜糖蛋白。它最初被认为是造血干/祖细胞的细胞表面标志物，最近也被确定为脑癌、结直肠癌和前列腺癌中的癌症干细胞标志物。AC133有两种同工型，一种是AC133-1，另一种是AC133-2。这两种同工型在功能上是冗余的还是发挥不同的功能仍不清楚。为了进一步探索CD133-2的生理和病理功能，我们制备了两种小鼠抗人CD133-2单克隆抗体（克隆6B3和9G4）。然后，我们仔细表征了这些单克隆抗体（MAb）的生物学功能，结果表明6B3和9G4与CD133的两个表位结合，这与市售抗CD133单克隆抗体（AC141）识别的表位不同。这两种单克隆抗体可用于细胞免疫染色、蛋白质印迹和免疫组织化学染色。我们进一步表明，单克隆抗体6B3可促进人骨髓白血病细胞系U937和人结肠腺癌细胞系SW480的生长，这表明CD133在这些细胞中发挥功能作用。作为一种有用的工具，这两种抗体对于进一步探索CD133的表达和功能可能具有重要价值。
