Schriever F, Riethmüller G, Johnson J P
Institute of Immunology, Müchen, FRG.
Hybridoma. 1988 Jun;7(3):249-53. doi: 10.1089/hyb.1988.7.249.
Monoclonal antibody (mAb) MacG1 was recently shown to detect a monosialoganglioside expressed in tumor infiltrating macrophages. The present study demonstrates with in vitro experiments that the MacG1 epitope is generated during cellular digestion in phagocytic monocytes. Following phagocytosis and degradation of MacG1 negative sheep red blood cells, the MacG1 epitope was expressed in intracytoplamsic granules of murine plastic-adherent peritoneal cells. Stimulation of adherent cells and phagocytosis alone did not lead to the expression of the MacG1 epitope. Chloroquine, which inhibits the activity of lysosomal enzymes, prevented the generation of the MacG1 epitope. Reactivity with mAb MacG1 appears to reflect a specific step during the enzymatic degradation of gangliosides and the antibody may provide a unique tool for analyzing this pathway.
单克隆抗体MacG1最近被证明可检测肿瘤浸润巨噬细胞中表达的一种单唾液酸神经节苷脂。本研究通过体外实验证明，MacG1表位是在吞噬性单核细胞的细胞消化过程中产生的。在吞噬并降解MacG1阴性绵羊红细胞后，MacG1表位在小鼠塑料贴壁腹膜细胞的胞质颗粒中表达。单独刺激贴壁细胞和吞噬作用并不会导致MacG1表位的表达。抑制溶酶体酶活性的氯喹可阻止MacG1表位的产生。与单克隆抗体MacG1的反应性似乎反映了神经节苷脂酶促降解过程中的一个特定步骤，该抗体可能为分析这一途径提供一个独特的工具。
