The IgM is really five IgG-type molecules that are linked together through disulfide bonds, such that their FC portions are all pointing in and their antibody binding portions are all pointing out.

gM是由五个IgG分子组成的,IgG分子之间通过二硫键连接,免疫球蛋白尾部的FC片段都指向内侧,而抗体的抗原结合位点都指向外侧

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