Oxelius V A, Eibl M M
Department of Paediatrics and Clinical Immunology, University Hospital, University of Lund, Sweden.
Clin Exp Immunol. 1996 Nov;106(2):203-7. doi: 10.1046/j.1365-2249.1996.d01-851.x.
IVIG is used as standard replacement therapy in primary antibody deficiency. IVIG consists mainly of IgG. IVIG preparations were investigated with respect to Gm allotypes, which are characterized by various amino acid epitopes in the constant heavy chains of the IgG subclasses IgG1, IgG2 and IgG3. The alternative allelic Gm allotypes G1m(a) and G1m(f) of IgG1, G2m(n) and G2m(") of IgG2 and G3m(g) and G3m(b) of IgG3 were measured by sensitive competitive ELISAs for G1m(a), G1m(f), G2m(n) and G3m(b). IgG subclass levels were quantified by radioimmunodiffusion (RID). Gm allotype quantities differed significantly in various IVIG products, with different products having half or double the amount of the different Gm allotypes. The results show the effect of the different manufacturing processes, but also indicate different physicochemical properties of Gm allotypes within the same IgG subclass. The different contents of Gm allotypes might be one reason for the variable levels of specific antibodies found in IVIG products. Immunodeficient patients with homozygous expression of Gm allotypes from IGHCG1, IGHCG2 and IGHCG3 were tested after infusion of foreign Gm allotypes. A prolonged survival was found for the G2m allotype, G2m(n), compared with G1m allotypes. Different half-lives were found for the alternative G1m(a) and G1m(f) allotypes, within the same IgG1 subclass.
静脉注射免疫球蛋白（IVIG）被用作原发性抗体缺陷的标准替代疗法。IVIG主要由IgG组成。针对Gm同种异型对IVIG制剂进行了研究，Gm同种异型的特征在于IgG亚类IgG1、IgG2和IgG3恒定重链中的各种氨基酸表位。通过针对G1m(a)、G1m(f)、G2m(n)和G3m(b)的灵敏竞争性酶联免疫吸附测定（ELISA）来检测IgG1的替代等位基因Gm同种异型G1m(a)和G1m(f)、IgG2的G2m(n)和G2m(")以及IgG3的G3m(g)和G3m(b)。通过放射免疫扩散法（RID）对IgG亚类水平进行定量。不同IVIG产品中Gm同种异型的量存在显著差异，不同产品中不同Gm同种异型的量为一半或两倍。结果显示了不同生产工艺的影响，但也表明同一IgG亚类内Gm同种异型具有不同的物理化学性质。Gm同种异型含量的不同可能是IVIG产品中特异性抗体水平变化的一个原因。对来自IGHCG1、IGHCG2和IGHCG3的Gm同种异型纯合表达的免疫缺陷患者在输注外来Gm同种异型后进行了检测。发现G2m同种异型G2m(n)的存活时间比G1m同种异型延长。在同一IgG1亚类内，替代的G1m(a)和G1m(f)同种异型具有不同的半衰期。
