We're exposed to things that might cause cancer where weren't exposed to them before and so that might be a reason.

我们暴露于可能致癌的物质中,这些物质在以前是没有的,这可能就是原因之一

耶鲁公开课 - 生物医学工程探索课程节选

Justin So Justin said it could be new things that are around and you're exposed to stuff we weren't exposed to before and that's true.

贾斯汀,贾斯汀认为我们周围的环境,出现了很多新物质,并且人们暴露在前所未有的环境中,这是事实

耶鲁公开课 - 生物医学工程探索课程节选

So, every time you're exposed to a new vaccine or a new antigen you go through this primary response before you have the secondary response.

所以,每当你接触到新疫苗或是新抗原,在再次免疫之前,机体将会经历这样的初次免疫过程

耶鲁公开课 - 生物医学工程探索课程节选

Yeah, so for example, you get exposed to-- before there was a vaccine your brother or sister had chickenpox, and so you got exposed to chickenpox naturally through your contact with them.

举个例子来说,如果你生活在这样的环境里,兄弟姐妹们还没接种疫苗就得了水痘,而你通过与他们相接触,在自然情况下接触到了水痘病毒

耶鲁公开课 - 生物医学工程探索课程节选

So, these memory cells are a way that your immune system keeps track of antigens that it's been exposed to for even if maybe the plasma cells that were producing antibody in response to the initial exposure have died and disappeared.

所以,这些记忆细胞,是人体免疫系统记忆抗原的一种方法,即使由浆细胞产生的抗体,在初次免疫应答中全部被消灭,记忆细胞仍然能迅速分化为抗体分泌细胞

耶鲁公开课 - 生物医学工程探索课程节选