Took it out of the virus completely, cloned it into a plasmid, that plasmid was expressed in a foreign host, in this case it was expressed in yeast cells.

将基因从病毒中完全提取出来,并克隆制成质粒,该质粒在外来宿主中表达,此例中质粒在酵母细胞中表达

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It's foreign, it's not part of the host or not a normal part of the host.

所以它成了外源物,外源物不是宿主的一部分,至少不是正常的一部分

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So, when the right signal is received, the right T-cell finds your host cell with a foreign virus in it, the first thing that happens is that this T-cell becomes activated and it starts reproducing, making more copies of itself.

所以 当接收到正确的信号,恰当的T细胞寻觅到,感染外源病毒的细胞时,首先发生的是,T细胞被激活并开始增殖,制造更多自身拷贝

耶鲁公开课 - 生物医学工程探索课程节选