Parekh R, Roitt I, Isenberg D, Dwek R, Rademacher T
Department of Biochemistry, University of Oxford, United Kingdom.
J Exp Med. 1988 May 1;167(5):1731-6. doi: 10.1084/jem.167.5.1731.
In a study of 151 normal, healthy individuals of both sexes varying in age from 1-70 yr, it was found that the relative incidence of agalactosyl (with both outer arms terminating in N-acetylglucosamine) N-linked oligosaccharides on total serum IgG decreased from birth to a minimum (at 25 yr of age) and then increased with age. The relative incidence of digalactosyl structures varied inversely to this, and the relative incidence of monogalactosyl structures was constant. Galactosylation of the N-linked oligosaccharides of the human serum IgG of normal individuals is therefore an age-related molecular parameter. Several reports have suggested that rheumatoid arthritis is associated with a decreased galactosylation of serum IgG (3-5). The normal variation in galactosylation with age as described here allows a true assessment of disease-associated changes in this parameter, and raises the possibility that one of the lesions in rheumatoid arthritis is an accelerated aging of the immune system. In addition, heterogeneity within age groups may be due to intrinsic differences in genetic endowment, or may reflect the impact of extrinsic factors (8).
在一项针对151名年龄在1至70岁之间的正常健康男女个体的研究中，发现血清总IgG上无半乳糖基（双臂末端均为N-乙酰葡糖胺）的N-连接寡糖的相对发生率从出生时开始下降，至最低值（25岁时），然后随年龄增长而上升。双半乳糖基结构的相对发生率则与此相反，而单半乳糖基结构的相对发生率保持恒定。因此，正常个体血清IgG的N-连接寡糖的半乳糖基化是一个与年龄相关的分子参数。有几份报告表明，类风湿性关节炎与血清IgG半乳糖基化降低有关（3 - 5）。此处所描述的半乳糖基化随年龄的正常变化，使得能够对该参数中与疾病相关的变化进行真实评估，并增加了类风湿性关节炎的病变之一可能是免疫系统加速老化的可能性。此外，年龄组内的异质性可能是由于遗传禀赋的内在差异，也可能反映了外部因素的影响（8）。
