The response to the second exposure in antigen is different in a couple of ways.

第二次接触相同抗原,免疫系统的应答,在以下几个方面是不同的

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You could probably find some antigens that don't follow exactly this behavior, but in general, this is the kind of behavior you would see on first exposure to an antigen or vaccine, called the primary exposure, and on subsequent exposure to an antigen or vaccine called the boost.

可能你也会发现,一些抗原并不完全遵循这种模式,但通常来说,在你首次接触一种抗原或疫苗时,都能观察到这种模式,它被称为初次免疫,而接下来的,再次接触抗原或是疫苗被称为增强免疫

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On second exposure it's different, that IgG is produced predominantly on second exposure to an antigen.

而再次免疫则不同,再次接触相同的病原体时,人体主要产生的则是IgG

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