Briefly describe the function of the immune system
The immune system keeps us fit and healthy and it protects us from -
- cuts and burns
- chemicals and toxins
- pathogens and bacteria
- it also monitors for internal threats
Describe the different components of the immune system
It is a complex organisation with communication between organs, tissues, cells and soluble mediators
How is the immune system divided ?
It is divided into the innate immune system and adaptive immune system
- they are constantly working together and there is huge overlap
What is the innate immune system ?
- we are born with it (doesn’t need to be learned)
- provides a rapid response
What is the adaptive immune system ?
- develops with age
- takes longer to become activated
- it is highly specific to the threat encountered
What is the outermost layer of the immune system and the first line of defence ?
- barriers which prevent threats from entering the body
E.g. mucus and skin
What are the primary lymphoid organs ?
- thymus
- spleen
- bone marrow
What is the function of white blood cells ?
They move around the body looking for sites of infection and if they do detect infection then soluble mediators come in to play to neutralise and communicate the threat
What is involved in the neutralisation of infection ?
The complement system
What is involved in the communication of infection ?
- cytokines : direct the immune response
- chemokines : direct the cells to the site of infection
What are the 4 Rs involved in the function of the immune system ?
Recognise
React
Regulate
Remember
Where do the cells of the immune system develop from ?
They develop from haematopoietic stem cells
Briefly describe haematopoietic activity
- between 1-3 months pre birthhighest in the yolk sac
- between 2-7 months pre birth highest in the liver and spleen
- between 5 months pre birth and 30 years old highest in long bones
- from birth upto the rest of life highest in the vertebra, ribs, sternum and pelvis
What is the myeloid lineage of the haematopoietic stem cells ?
This lineage gives rise to cells of the innate immune system
What is the lymphoid lineage of the haematopoietic stem cells ?
- gives rise to innate lymphoid cells
- only respond to generalised things
- not involved in memory
Which cells act as a link between the innate and adaptive immune system ?
Dendritic cells
