So, these are better at binding to antigen because they have more binding sites on them.

连接抗体是对付抗原的有效方法,因为抗体表面将会有更多的抗原结合位点

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They also have binding sites for antigen, but they are sort of two IgG type molecules bound together by another peptide chain.

同样IgA抗体表面也有与抗原结合位点,但它们就像两个IgG型分子,通过肽链相互连接

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