© The Nobel Committee for Physiology or Medicine. Ill. Mattias Karlé

Nobel Prize lessons – The immune system’s security guards

The Nobel Prize in Physiology or Medicine 2025 is about our immune system. The immune system protects us from viruses, bacteria and other kinds of microorganisms. The Nobel laureates Mary Brunkow, Fred Ramsdell and Simon Sakaguchi have discovered previously unknown immune cells, so-called regulatory T cells, that act as the immune system’s security guards and prevent immune cells from attacking our own body. 

Help us improve the content – Five quick questions and a comment

Slideshow or text for students (10 minutes)

Slideshow

Speaker’s manuscript

Text for students

Video with Nobel expert (2 minutes)

Show the video with an expert explaining the benefits of the prize-awarded work.

Student assignments (5-10 minutes)

Finish by having the students carry out one of the following assignments:

Summarise the prize in your own words, in pairs or smaller groups.

Write down a reason (citation) for why the prize was awarded: The Nobel Prize in … 2025 is awarded [names of the laureates] for their [reason for being awarded the prize]. The citation should be one sentence long.

Explain what the following terms mean: immune system, microbes, thymus, T cells, eliminated, autoimmune diseases.

Help us improve the content – Five quick questions and a comment

Links for further information

Press release for the 2025 Nobel Prize in Physiology or Medicine including illustrations

Popular information about the 2025 Nobel Prize in Physiology or Medicine

A Nobel Prize lesson about Alfred Nobel and the Nobel Prize

To cite this section
MLA style: Nobel Prize lessons – The immune system’s security guards. NobelPrize.org. Nobel Prize Outreach 2025. Fri. 5 Dec 2025. <https://www.nobelprize.org/nobel-prize-lessons-the-2025-medicine-prize/>