t cells 1 Flashcards
what is the genetic condition that causes no adaptive immunity
SCID
what drug is used to model the importance of t cells vs b cells
fingolimod
where are t cells generated
bone marrow
where do t cells mature
thymus
what does the maturation process allow for the generation of and why is this important
extensive range of t-cell receptors
allows the recognition of millions of amino acid sequences as being foreign which leads to an immune response
what are t cells effector function
(hint - 4 functions)
killing cells directly
helping b cells make antibodies
producing lots of cytokines
activating other cells in the immune system
what do t cells respond to
peptides presented in MHC molecules
what type of cells are specialised t cells produced from
a naive cell
what type of t cells is cytoxic
CD8+ t effector cell
what type of t cell is a helper t cell
CD4+ t effector cell
where will the types of t cells vary
in different organs
how will t cells recognise an antigen
only through their t cell receptors when the antigen is bound
what is necessary to be present for a TCR to recognise an antigen
only when it is bound within a MHC molecule
why do can t cells only recognise antigens under certain conditions
as without control there can be a lot of damage to the cells
what else can the TCR recognise
infected cells
what are the two domains of the tcr
constant and variable
what is the name of the region that makes contact with the antigen
the complementary determining region
how are the t cell receptors so diverse and show does it work
vdj recombination
the genes that make up the tcr gene locus rearrange to make many receptors
what is combination diversity
where you get range from the different combinations of gene segements
what is junctional diversity
where you get range from the addition of nucleotides after recombination occurs
where are the most variable regions of the tcr and why
where the segments join
junctional diversity where more nucleotides are added when the segments are joined
what is antigen presentation
where an MHC molecule will bind to proteins from viruses and bacteria and present them to t cells
