Geltosky J E, Weseman J, Bakke A, Lerner R A
Cell. 1979 Oct;18(2):391-8. doi: 10.1016/0092-8674(79)90058-8.
Analysis of the composition of cell surface-associated glycoproteins of D. discoideum by lactoper-oxidase-catalyzed radioiodination, followed by isolation by Con A-Sepharose chromatography, revealed that the developmentally regulated cell surface expression of a certain glycoprotein (gp150) parallels the onset of mutual cellular cohesiveness (Geltosky, Siu and Lerner, 1976). We have purified gp150 and raised specific antibodies to it. Through utilization of the specific antibody and a fluorescence-activated cell sorter, the expression of gp150 on the cell surface has been studied. Starting from a low level in noncohesive (vegetative) cells, there is a rapid accumulation of gp150 on the surfaces of aggregating cells. A peak level of expression is achieved by 10 hr and maintained at least until the steps of terminal differentiation. Most significantly, monovalent Fa'b derived from anti-gp150, when added to aggregation-competent cells, blocks the cells' ability to reaggregate. Fab's derived from antisera with different specificities were ineffective inhibitors of cell aggregation. These results suggest that gp150 serves an intimate role in cell adhesion.
通过乳过氧化物酶催化的放射性碘化作用分析盘基网柄菌细胞表面相关糖蛋白的组成，随后用刀豆球蛋白A-琼脂糖凝胶层析法进行分离，结果显示某种糖蛋白（gp150）在发育过程中受调控的细胞表面表达与细胞间相互黏附性的开始是平行的（格尔托斯基、萧和勒纳，1976年）。我们已纯化了gp150并制备了针对它的特异性抗体。通过利用特异性抗体和荧光激活细胞分选仪，对gp150在细胞表面的表达进行了研究。从非黏附性（营养）细胞中的低水平开始，gp150在聚集细胞表面迅速积累。在10小时时达到表达峰值水平，并至少维持到终末分化阶段。最显著的是，源自抗gp150的单价Fab片段，当添加到具有聚集能力的细胞中时，会阻断细胞重新聚集的能力。源自具有不同特异性抗血清的Fab片段不是细胞聚集的有效抑制剂。这些结果表明gp150在细胞黏附中起着密切作用。
