Why the lag phase at the beginning?

为什么迟滞期在应答初期出现
Well, because it takes some time for

因为我之前提及的细胞活动
these cellular events that I mentioned earlier to happen.

需要一些时间完成
The antigen has to be presented to helper T-cells,

抗原需要被呈递给辅助性T细胞
those helper T-cells have to stimulate

这些辅助性T细胞需要激活B淋巴细胞
a B-cell population to both proliferate and differentiate.

使其增殖和分化
So, this is a picture I showed you before.

这张图片我之前给你们展示过
You can imagine that

你可以想象
even when this immature B-cell gets the signal now is the time,

即使不成熟的B淋巴细胞一得到信号
you need to turn on antibody production,

就开启了抗体制造过程这也需要时间
that it takes some time for it to both proliferate to make enough cells

一方面需要繁殖得到足量的B细胞
and for those cells

另一方面这些细胞