Helen Marriott staff webpage: https://www.sheffield.ac.uk/medicine/people/iicd/helen-marriott
Twitter: @shefuni_iicd

Vaccines prevent disease by training our body’s immune system to identify and attack pathogens (a virus or bacterium that can cause illness) that we have not come into contact with before. By harnessing the power of the immune system, vaccines enable the body to quickly produce the right antibodies to fight a particular disease. Antibodies are molecules produced by the immune system that attach to specific antigens (a molecule that forms part of a pathogen) enabling other parts of the immune system to locate and attack the pathogen. These antibodies are a key part of the immune system’s defences, working alongside different types of white blood cells to detect and destroy pathogens.

Dr Helen Marriott’s research focuses specifically on macrophages and their role in combating respiratory pathogens. Macrophages are a type of specialised white blood cell that can detect and destroy pathogens and other foreign cells by engulfing and digesting them - a process which is called phagocytosis.

Find out more about vaccines, pathogens and the immune cells with the activities below.

How do vaccines work?
Activity recommended for ages 7+

Watch the British Society for Immunology’s video explaining how vaccines work.

Pathogen Buster!
Courtesy of the British Society for Immunology
Activity recommended for ages 7+

Play the Pathogen Buster game and learn how antibodies fight pathogens inside the body, what antibody specificity is, and how vaccines work.

For this game you will need:

• Slime (you can use our snot recipe for this!)

• Tweezers

• Large tweezers or kitchen tongs

• Dried pasta shells

• Pipe cleaners or straws

• Pompoms or cotton wool balls

• Plastic container or plate

• Timer

Set up:

• In a big bowl, add or make your own slime

• Mix small pieces of pasta, pipe cleaners and pompoms into the slime in a big bowl. These items represent different pathogens.

• Prepare the different sized tweezers / tongs and an empty plastic container.

• Get your timer ready.

What to do:
Every organism, or living thing, is made up of structures called cells. The cell is the smallest unit with the basic properties of life. We are all made up of cells! There are times that a pathogen gets into our body and attack our cells!

Pathogens are germs, such as bacteria and viruses, that can kill our cells. When that happens, we become sick.

To fight those pathogens, our immune system produces antibodies, which stick to the intruders and help our body destroy them and make us feel better. However, these antibodies have to be familiar with the pathogens that enter our body and recognise them as intruders. To fight your enemy, you must know your enemy!

What if a new germ enters our body?
The slime is our cells and pathogens are the pieces of pasta, pipe cleaners, and pompoms. The tweezers act as antibodies which will remove the pathogens.

1. You will use the fine tweezers to remove the pasta shapes. Close your eyes and attempt to do the activity for 20 seconds. You can place the removed objects in the empty plastic container.

Was it difficult or easy? Were you able to remove the right object? Just like in real life, if the body has never seen the germ before, it takes some time to produce antibodies and remove the pathogen from our cells. Our body also has to produce specific antibodies for each pathogen, which is called antibody specificity, so having the right tweezers is essential to the game!

2. Now try the game again, but this time no need to close your eyes and now use the jumbo tweezers. Do the activity again for 20 seconds.

Was it easier now that you are familiar with the pathogen that you were trying to remove?

This is how vaccinations work. A vaccine contains a harmless killed or weakened form of a pathogen. When our immune system detects these, we produce the specific antibody to fight it off. But it's like a practice round, so that when we encounter the pathogen again, we have the correct antibodies and our immune system is ready to defeat it!

3. You can try removing different objects from the slime using the different sized tweezers.

Build your Own Virus
Courtesy of the MRC - University of Glasgow Centre for Virus Research
Activity recommended for ages 7+

Viruses are tiny but powerful; if you catch a viral infection it can make you feel really unwell. Viruses are smaller than most cells, including human cells and bacteria. Plants, animals and humans can all catch viruses. Some viruses can infect both people and animals.

A virus can get into your body by going up your nose when you breathe in or pass from your hands into your mouth. Once they are inside your body, they use your cells to make more of themselves – turn cells into virus-making factories.

When you sneeze the new viruses fly back out of your nose and spread to other people. That’s how coughs and sneezes spread diseases.

Viruses may just be small packages of genetic information, but they can cause some really nasty diseases! If our cells are busy making viruses, they can’t do the job they’re meant to do, so we become ill. You are going to make a virus today and then we’ll look at what kind of disease it causes.

Scientists have developed vaccines to help protect us from many common viruses. Your body also has its own immune system and this helps to fight infection by viruses too. Medical Research Council scientists study viruses to learn how they get inside our cells and make us ill. They hope to work out how to treat people and animals that catch diseases caused by viruses.

Make a virus using genetic material (shredded paper), capsid (play dough) and protein spikes (pins or plastic pegs)

Set up:

To build your own virus you will need...

• Play dough capsid: The play dough will form the tough outer coat of your virus. Scientists call this protective coat the virus capsid. It protects the genetic material inside and is made of lots of smaller molecules called proteins that your immune system recognises as invaders. If you don’t already have play dough you can make your own by following these instructions.

• Paper DNA: The shreds of paper represent the virus’s genetic material, the DNA or RNA that give instructions for it to hijack cells.

• Virus spike pegs: The pegs are the spikes a virus uses to grip onto cells and then get inside to cause infection.

Different viruses have different patterns and shapes of spikes that allow them to infect different kinds of cells. Before starting, pick your virus design:

• Influenza (achy): blue air dough, blue round headed pins and green stalk like pegs

• Adenovirus (snotty): red air dough, flat topped pins with six sides, green stalk like pegs

• Norovirus (poopy): yellow air dough, red mini pegs arranged in hexagonal shapes

• Ebola (deadly): red air dough, long thin shape with looped end, blue mini pegs

What to do:
1. Take some shredded paper to represent the RNA or DNA in your virus

2. Take the play dough, flatten it out, put the genetic material (shredded paper) inside and roll it into a ball to represent the tough outer coat or capsid

3. Select your pins or plastic pegs to represent the glycoprotein spikes on the capsid used by the virus to grip on to cells

4. Stick the glycoprotein spikes (pins or pegs) into the capsid (play dough) to complete your virus model!

Colouring sheet downloads
Activity recommended for ages 7+

MRC Virus Colouring Sheet (PDF)
BSI Our Heroic Bodies Colouring Sheet (PDF)

Ask Dr Helen Marriott a question about vaccines or the immune system

Submit your question

The answers to your questions will be available here on Friday 5 June 2020.

For more information and education resources about vaccines and immunology, visit the Celebrate Vaccines website.

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