Cianfriglia M, Cenciarelli C, Tombesi M, Barca S, Mariani M, Morrone S, Santoni A, Samoggia P, Alessio M, Malavasi F
Laboratorio di Immunologia, Istituto Superiore di Sanità, Rome, Italy.
Int J Cancer. 1990 Jan 15;45(1):95-103. doi: 10.1002/ijc.2910450118.
We describe a murine IgG1 monoclonal antibody (MAb56), specific for a cell-surface protein structure (MC56 determinant) expressed by the human CEM cell line. A large band of approximately 90 kDa was identified as the main specific component of the MC56 determinant. Such a 90-kDa protein is significantly associated with the drug-sensitive phenotype, its expression being progressively reduced quantitatively in multi-drug-resistant (MDR) variants of CEM cells, according to the extent of drug resistance. In addition, the MC56 determinant is expressed de novo in drug-sensitive revertant cell lines derived from MDR cells and unreactive with the MAb56. The MAb56 shows a high affinity towards the immunizing drug-sensitive CEM cell line (Ka = 1.86 x 10(9) L/mole) while not binding to MDR cell variants. The expression of the MC56 molecule on a variety of human cells and tissues makes such a cellular determinant a candidate as a marker for studying the MDR phenomenon both in vivo and in vitro.
我们描述了一种鼠源IgG1单克隆抗体（MAb56），它对人CEM细胞系表达的一种细胞表面蛋白结构（MC56决定簇）具有特异性。一条约90 kDa的大条带被鉴定为MC56决定簇的主要特异性成分。这种90 kDa的蛋白与药物敏感表型显著相关，根据耐药程度，其在CEM细胞的多药耐药（MDR）变体中的表达量逐渐减少。此外，MC56决定簇在源自MDR细胞且与MAb56无反应的药物敏感回复细胞系中重新表达。MAb56对免疫用的药物敏感CEM细胞系具有高亲和力（Ka = 1.86 x 10(9) L/摩尔），而不与MDR细胞变体结合。MC56分子在多种人类细胞和组织上的表达使得这种细胞决定簇成为体内和体外研究MDR现象的标志物候选。
