What happens is your immune response goes haywire and then your body starts to attack itself, so theres a failure to shutdown.

VOA: special.2010.03.16

So, the antigen we're thinking about is a vaccine particularly designed to elicit immune response against a pathogen.

我们现在考虑的这种抗原,是一种特别设计的疫苗,它能够诱发免疫效应以消灭病原体

耶鲁公开课 - 生物医学工程探索课程节选

That can be a very strong amplifying response, and that happens in the immune system in many cases.

这可能会产生非常强的放大效应,这种效应在免疫系统中很常见

耶鲁公开课 - 生物医学工程探索课程节选

In particular, low-status individuals showed high levels of activity in genes associated with the production of various immune-related cells and chemical signalling factors, as well as those to do with inflammation (a general immune response that involves tissue swelling and increased immune-cell activity in the affected area).

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Though the placebo effect remains largely shrouded in mystery, researchers attribute some aspects of the placebo response to active mechanisms in the brain that can influence bodily processes such as the immune response and release of hormones.

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Cells use cytokines to communicate with each other, and to regulate the immune response.

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