Once the pathogen is destroyed, most of the clonally expanded cells die off, that's called clonal deletion.

一旦病原体被摧毁了，大部分克隆扩增的细胞会死亡，这被称为克隆清除。

But some of the clonally expanded cells live on as memory cells and they're ready to expand once more if that pathogen ever resurfaces.

但一些克隆扩增的细胞会作为记忆细胞存活下来，以待病原体下一次露面时再次扩增。