老化红细胞膜表面抗原的研究

红细胞的老化是一个复杂的问题,对其老化机制争论较多,最近有人提出老化红细胞表面可结合自身IgG,然后被巨噬细胞及网织内皮细胞识别而清除,但缺乏直接的证据。本文用过氧化物酶标记Protein A与年轻及老化红细胞保温,老化红细胞结合的IgG是年轻者的两倍多。用FITC标记IgG抗体在流式细胞荧光检测仪测定,结果与酶标者一样。如用神经氨酸酶处理年轻红细胞,可提高酶标记及荧光标记的量,再用β-半乳糖苷酶水解,其标记量下降。实验结果说明老化红细胞表面确有IgG结合,其结合与半乳糖基有关。

The Study of Natural IgG on Human Normal Senescent Red Blood Cells

The purpose of the Present research was to study how the human normal senescent red blood cells(RBC) are Phagocytized and removed by niacrophages. The results showed that human senescent RBC are removed from the circulation following the binding of autologous IgG, The Fe Portion of the membrane-bound IgG is recognized by niacrophages which, in turn, phagocytize the senescent RBC. Further research work indicates that the binding of autologous IgG to human senescent RBC are closely associated with the terminal sugar residues of glycoproteins on the senescent RBC membrane. Possibly, the galactose residue is exposed after the terminal sialic acid residue is hydrolyzed with the aging of RBC, and then produce a new antigen which is able to bind autologous IgG. If, however, the galactose residue is continuously hydrolyzed, the RBC will be unable to bind autologous IgG.