Immunology 3 Flashcards
What is the receptor found on a T cell called, and how do these differ on CD8+ from CD4+
It is called the T cell receptor, recognises antibody when bound to MHC I on cytotoxic CD8+ cells or MHC II on CD4+ helper T cells
When will a T cell recognise the antibody?
When bound to MHC
What are the two types of T cell?
CD4+ - Stimulate B cells to produce antibody
CD8+ - Cytotoxic T cells
What are T cells ‘Taught’ during maturation in the thymus?
They are taught to recognise own MHC - those that identify it as yours are allowed to live and move on to the next test, after that the T cell isn’t allowed to recognise MHC plus own peptide
When do T cells mature into CD4 + and CD8+ cells?
After they have been ‘taught’ to recognise MHC
Where can you find MHC class 1 proteins?
Virtually all nucleated cells
What is the function of the MHC class 1 molecule?
Presents antigenic peptide, Showi the CD 8+ T cell what is being produced in the cell, triggers a cytotoxic response - releases perforin, releases granzyme B, a protese that enters the cell through the pore and causes apoptosis
Where can you find MHC class 2 proteins?
In antigen presenting cells, such as B cells, macrophages and dendritic cells.
What is the function of MHC class 2 receptors?
Presents antigenic peptides to CD4 helper T cells which activates macrophages and B cells
Why are T cells said to have memory?
They are capable of remembering what has activated them once. Meaning on second exposure they can activate faster and stronger
