But the CTLs do sometimes need to be reined in.

但有时确实需要控制 CTL。

Fortunately, the CTLs can be turned off by activating a molecule called PD1.

幸运的是，可以通过激活一种叫做 PD1 的分子来关闭 CTL。

Thanks to the monoclonal antibodies, all of the CTLs are fully activated and can blast away the cancer.

多亏了单克隆抗体，所有的 CTL 都被完全激活，可以消灭癌症。