The one that's on the top here is called ligand-gated ion channel and an ion channel is a protein that sits in the surface of a cell.

最上面的这个叫作配体门控离子通道,离子通道是一类位于细胞表面的蛋白

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That's making the cell look foreign because some of that foreign protein is on the surface with MHC1.

这使得整个细胞亦被视为外源物,因为某些外源蛋白,和MHC1共同出现在细胞表面

耶鲁公开课 - 生物医学工程探索课程节选