Question: what is your favourite part of the immune system?

Joanna Giles answered on 20 Nov 2012:

That is so tricky because I think the immune system on the whole is just SO amazing!
I think I would maybe choose the white B cells as they are able to become plasma cells to produce absolutely millions of a certain antibody that is so so specific to whatever pathogen has invaded us. We have millions of these B cells ready and waiting in our bodies, each with their own specific antibody – they protect like an army – and when a certain pathogen attacks – our B cells are activated to multiply and secrete antibodies.

B cells also have another job, and that is to act as something called an “Antigen presenting cell”. This means that they also have the ability to eat up pathogens (by engulfing them and breaking them up) and display on their cell surface some of the fragments of the pathogen. So, not only do B cells make antibodies, they also eat up pathogens AND alert the other players of the immune system on what to look out for! Talk about multi-tasking!