translation.en: And as he watched the disease unfold, he was able to discover that actually the motor neurons were dying in the disease in a different way than the field had previously thought. There was another kind of cell that actually was sending out a toxin and contributing to the death of these motor neurons, and you simply couldn't see it until you had the human model.
translation.zh: 而且，这位科学家在观察病变过程时发现， 在这种疾病中，运动神经元的死亡过程 与此前学术界推想的情况并不相同。 其实是有另一种细胞 释放出一种毒素， 促使运动神经元死亡。 之前无法发现这一点， 是因为还没有使用人体细胞建模。