Lutz H U, Fehr J
J Biol Chem. 1979 Nov 25;254(22):11177-80.
Glycophorins extracted from membranes of young and old human red blood cells have within an error of +/- 1.5% the same sialic acid content when referred to a relative measure of the number of glycophorins. The degree of surface iodination in glycophorins, which was shown to be the same in young and old cells, served as this relative measure. This finding implies that senescent human red blood cells hardly reveal desialylated surface proteins (less than or equal to 3%). However, the sialic acid content per cell was repeatedly reported to be 10 to 15% lower in old than in young cells. Therefore, we conclude 1) that human red blood cells lose intact glycophorin together with membrane during red blood cell senescence, and 2) that removal of desialylated and senescent red blood cells from the circulation proceeds by different routes.
从年轻和年老的人类红细胞膜中提取的血型糖蛋白，以血型糖蛋白数量的相对测量值为参照，其唾液酸含量的误差在±1.5%以内。血型糖蛋白的表面碘化程度在年轻和年老细胞中相同，以此作为这种相对测量值。这一发现表明，衰老的人类红细胞几乎没有显示出去唾液酸化的表面蛋白（小于或等于3%）。然而，据反复报道，每个细胞的唾液酸含量在年老细胞中比在年轻细胞中低10%至15%。因此，我们得出结论：1）人类红细胞在衰老过程中会与膜一起丢失完整的血型糖蛋白；2）从循环中清除去唾液酸化和衰老的红细胞是通过不同途径进行的。
