All immunology text books will cover the structure, function and development of lymphocyte receptors in some depth. There are a couple of relevant animations on gene recombination (relevant to ‘antigen recognition 1′ podcast) and T cell development (relevant to ‘antigen recognition 2′ podcast) on the Janeway Immunobiology CD (I am using the green one - 7th Edition). I mentioned Zinkernagel and Doherty who won the Nobel Prize for Medicine in 1996 because of their discovery of MHC restriction. Take a look here:
My edition (4th) of Kuby Immunology is a bit old now, so here is an updated link:
Kuby Immunology 6th Edition
Also take a look at my immunology open learning (in SunSpace) and all the relevant glossary terms.
If you wan...
In the last podcast (adaptive recognition 1) I introduced the concept of rearranged BCR and TCR. Now, I will summarise (1) what these antigen receptors recognise and (2) how these randomly generated receptors don’t recognise and destroy your own tissue. I also introduce a very important set of ‘peptide receptors’ or MHC molecules (in humans, we call our MHC Human Leukocyte Antigens or HLA). We have two classes of MHC molecule - class I MHC which is expressed on all body cells and display intracellular peptides (~9 amino acids long) and class II MHC which are generally only expressed on specialised ‘antigen presenting cells’ and display extracellular peptides (~22 amino acids long). So you can see that these ‘adaptive’ antigen receptors are very different from our innate ’sensors’ of danger.
All organisms (plants, animals, insects) can make innate responses. In addition, all organisms with a backbone and a jaw can make adaptive immune responses. This enables them to make a specific immune response against absolutely anything and also to remember it and make a better response next time - the very principles that underpin vaccination. The cell type that enables this to happen is the lymphocyte (T and B) and these remarkable properties are a direct consequence of they way they recognise things …. things that are dangerous like infectious agents (the word ‘antigen’ is used to describe anything that stimulates an immune response as it is clear we can make adaptive immune responses against harmless things too). This podcast summarises the properties of T cell and B cell antigen receptors (BCR, TCR) - unlike innate receptors they are highly diverse, rearranged receptors which have been randomly generated. The following podcast summarises the key points on adaptive receptors. The...
If you want to find out more, there are many excellent text books. My personal favourites include Janeway’s Immunobiology or Kuby Immunology. This short podcast just highlights a couple of relevent animations on innate recognition and sections from Immunobiology. Also take a look at the companion website for Kuby Immunology:
PS if you want to know why they are called toll like receptors - take a look at this great resource (click on the links below):
The interactive fly & it’s to...
We have two kinds of immunity, innate and adaptive, which are completely different in they way they recognise things that are dangerous. Innate responses are biased to the enemy (pathogens like fungi, bacteria and viruses), and the receptors recognise common microbial structures. In that sense they are not ’specific’ but ‘cross reactive’. When danger is ’sensed’ then signals are sent to the nucleus which result in the activation of immune response genes. This sensing of danger is co-ordinated by families of highly conserved genes including the toll-like receptors (TLR), NOD-like receptors (NLR) and RNA helicases (RLR). Ultimately this drives the quality and the quantity of the specific (or adaptive) immune response that follows. The following podcast summarises the key points on innate recognition.
Immunology is the most fascinating subject and is about how the body defends itself from diseases (eg caused by bacteria, viruses, cancer). The purpose of this series of podcasts is to support my introductory lectures on immunology to undergraduate students at the University of Sunderland. Put simply:
What is the immune system and how does it work?
If you want to see some background material - take a look at:
Some background material as a taster…