Lectin analysis of human immunoglobulin G N-glycan sialylation
Lectin analysis of human immunoglobulin G N-glycan sialylation
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DOI：
10.1023/a:1007183915921
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发表时间：
1999-12-01
影响因子：
3
通讯作者：
Axford, JS
中科院分区：
文献类型：
--
作者：
Dalziel, M;McFarlane, I;Axford, JS
分别用α 2、6链唾液酰化特异性凝集素Sambucus nigra凝集素（SNA）和末端半乳糖特异性凝集素Ricinus communis凝集素（RCA）研究了人免疫球蛋白G （IgG）唾液酰化的发生、连锁和分布。SNA仅与n -聚糖α 2,6-链唾液酸结合。唾液酸酶分析证实，这是显性的，如果不是排他的连锁。使用生化唾液酸测定法估计总IgG唾液化为1.0杯SA/mg IgG（或约0.5摩尔/摩尔）。SNA在原生状态和变性状态下均与IgG Fab片段有较强的结合。相比之下，SNA在其天然形式下不能与IgG Fc片段结合，但在Fc变性后表现出很强的结合。这使得构建能够同时测量IgG Fab和Fc alpha2,6-唾液酰化的定量分析，而不需要酶切肽。
The lectins Sambucus nigra agglutinin (SNA) and Ricinus communis agglutinin (RCA), specific for alpha2,6 linked sialylation, and terminal galactose respectively were used to study the occurrence, linkage and distribution of human immunoglobulin G (IgG) sialylation. SNA was shown to bind N-glycan alpha2,6-linked sialic acid only. Sialidase analysis confirmed that this is the dominant, if not exclusive linkage. Total IgG sialylation was estimated at 1.0 mug SA/mg IgG (or about 0.5 mole per mole) using a biochemical sialic acid assay. SNA displayed strong binding to the IgG Fab fragment in both its native and denatured state. In contrast, SNA failed to bind the IgG Fc fragment in its native form, but displayed strong binding after the Fc was denatured. This allowed the construction of quantitative assays capable of measuring both IgG Fab and Fc alpha2,6-sialylation without the need for enzymatic peptide digestion.