What makes it so safe that it can be put in one of the most sensitive places in your body, in contact with your eye?

是什么使得它足够安全,以至于能放到眼睛,这个人体最敏感的器官之一上

耶鲁公开课 - 生物医学工程探索课程节选

By cell/cell contact, I mean that there's a receptor in one cell that makes some kind of a chemical interaction with a receptor in another cell.

通过细胞之间的接触,我的意思是在一种细胞上的受体,能与另一细胞上的受体发生某种化学反应

耶鲁公开课 - 生物医学工程探索课程节选