Harris D T, Jaso-Friedmann L, Evans D L
Department of Microbiology and Immunology, University of Arizona, Tucson 85721.
Scand J Immunol. 1994 Jan;39(1):73-8. doi: 10.1111/j.1365-3083.1994.tb03342.x.
Recently, a panel of monoclonal antibodies (MoAbs) was developed that identified a novel tumour-cell antigen conserved across species (mouse, rat and man). Fluorescence-activated cell sorter (FACS) analysis demonstrated that this antigen was expressed at highest levels on human tumour cell lines sensitive to natural killer (NK)-cell lysis. These MoAbs inhibited NK cell lysis of K562 target cells (by up to 90%), as well as a variety of other NK-sensitive target cells. Biochemical analyses revealed that the MoAbs reacted with a polypeptide of 42 kDaltons, distinct from other known cell surface antigens. Now the expression of this antigen has been analysed further with a panel of 24 tumour cell lines to determine its role in NK cell function. The expression of target cell major histocompatibility complex (MHC) molecules in conjunction with sensitivity to NK cell lysis was examined also. For each of the 24 cell lines it was found that the level of expression of the novel target cell antigen determined the sensitivity of the cell line to NK cell lysis. However, the level of MHC antigen expression could modulate target cell sensitivity to NK cell lysis, in that high levels of MHC class-I molecule expression resulted in a target cell that was insensitive to NK cell lysis regardless of the level of expression of the novel antigen. Thus, for most transformed cell lines, sensitivity to NK cell lysis appeared to be determined by the expression and levels of the novel antigen in association with MHC class-I molecules.
最近，一组单克隆抗体（MoAbs）被研发出来，它们识别出一种在物种间（小鼠、大鼠和人类）保守的新型肿瘤细胞抗原。荧光激活细胞分选仪（FACS）分析表明，这种抗原在对自然杀伤（NK）细胞裂解敏感的人类肿瘤细胞系上表达水平最高。这些单克隆抗体抑制了NK细胞对K562靶细胞的裂解（高达90%），以及多种其他NK敏感的靶细胞。生化分析显示，这些单克隆抗体与一种42千道尔顿的多肽发生反应，该多肽与其他已知的细胞表面抗原不同。现在，已用一组24种肿瘤细胞系进一步分析了这种抗原的表达情况，以确定其在NK细胞功能中的作用。同时还检测了靶细胞主要组织相容性复合体（MHC）分子的表达与对NK细胞裂解的敏感性之间的关系。对于这24种细胞系中的每一种，都发现新型靶细胞抗原的表达水平决定了细胞系对NK细胞裂解的敏感性。然而，MHC抗原的表达水平可以调节靶细胞对NK细胞裂解的敏感性，因为高水平的MHC I类分子表达会导致靶细胞对NK细胞裂解不敏感，而与新型抗原的表达水平无关。因此，对于大多数转化细胞系来说，对NK细胞裂解的敏感性似乎是由新型抗原与MHC I类分子的表达及水平所决定的。
