Some T cells (T8 cells) are cytotoxic or killer cells; they act directly on cells bearing antigen (tumor cells and tissue transplanted from an organ donor).

一些T细胞（T 细胞）是细胞毒性或杀伤细胞;它们直接作用于携带抗原的细胞（肿瘤细胞和从器官供体移植的组织）。

And another xenotransplantation breakthrough this week: Five human subjects have been found to grow new muscle, thanks to tissues transplanted into them from -- you guessed it -- pigs!

本周另一个异种移植突破：五名人类受试者被发现长出了新肌肉，这要归功于从——你猜对了——猪身上移植的组织！