分离人外周血的轻龄和老龄红细胞,采用麦胚凝集素和胶体金对红细胞表面的唾液酸残基进行细胞化学标记,然后在AFM下成像并进行数据分析。结果显示,老龄红细胞膜表面胶体金标记的颗粒数量明显低于轻龄红细胞表面,两者之间有显著差异。推测红细胞老化过程中细胞膜表面唾液酸含量的变化可能与老化细胞的处理机制有关。免疫胶体金标记结合原子力显微镜可在纳米尺度对膜受体蛋白进行定位和定量研究,拓展了原子力显微镜在生命科学领域的应用。
The young and old erythrocytes were isolated from whole blood samples. The sialic acids on erythrecyte membranes were cytochemically labeled by wheat germ agglutinin with colloidal gold and observed by atomic force microscopy, and the data were processed by analysis software. The results showed that the number of gold particles on old erythrocytes was significantly lower than that on young erychrocytes and there is significant statistic difference. It is concluded that the change of sialic acids on the membrane of erythrecytes during in vivo aging might be related with the process of aged erythrecytes. Combining immunogold labeling with AFM imaging could determine the location and quantitative date of receptor protein on membrane surface, and this will extend the application of atomic force microscopy in life science.