基于Percoll密度梯度法的轻老龄红细胞膜表面电荷的研究

Membrane Surface Charge Of Young and Old RBC Based On Percoll Density Gradient Separation Method

红细胞衰老过程中膜表面电荷的变化情况与其结构功能密切相关。针对以往研究对轻老龄红细胞膜表面电荷的差异性不确定的问题,本文从不同的细胞分离方法分离轻老龄红细胞的效果不同的角度,通过比较分离出的轻老龄红细胞表面唾液酸的含量和细胞膜的弯曲弹性模量Kc值,提出高速离心法和Percoll密度梯度离心法分离出的轻老龄红细胞间的细胞年龄差距不同,Percoll法分离出的细胞年龄差距更大。利用Percoll密度梯度离心法,进一步分离出四种不同细胞年龄的红细胞,由红细胞表面唾液酸的含量和表面Zeta电位值检验轻老龄红细胞膜表面带电状态的差异性,结果显示,轻老龄红细胞的膜表面电荷存在明显差别,且随着细胞年龄的增长,红细胞的膜表面负电荷逐渐减少。研究结果对红细胞的衰老机制及体内清除老化红细胞的途径等研究具有重要意义。

The surface electrical characteristics of aging erythrocytes are closely related to its structural functions. Owing to the uncertainty of the difference between young and old RBC＇s membrane surface charge, in this study, we compared the separated results of young and old erythrocytes by the methods of high speed centrifugation and Percoll density gradient separation. With the results of membrane surface sialic acid content and membrane elastic modulus Kc, it was found that using Percoll density gradient separation method to separate young and old erythrocytes is better than using high speed centrifugation, and the cell age gap between young and old erythrocytes is more greater. Further, four kinds of erythrocytes with different cell ages were separated by Percoll. Their surface membrane Zeta potential and sialic acid content are obviously different, indicating that the membrane surface negative charge of young RBC is different from the old one, which would get lower and lower with the increased cell age. The result is benefit to solve the mechanism of aging erythrocytes and the clearance pathways of aging erythrocytes in vivo.