B2 antigen processing and presentation Flashcards

antigen processing and presentation

1
Q

what does the t cell recognise

A

antigen
phagocytosis generates lots of short peptides from pathogen associated proteins and this is what t cells recognise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how is antigen recognised

A

peptides presented to TCR in context of major histocompatibility complex (MHC)
- 2 forms
MHC I CD8 t cells
MHC II CD4 t cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how antibodies and TCR recognise antigens

A

-the epitopes recognised by t cell receptors are often buried
-antigen must first be broken down into peptide fragments
-the epitope peptide binds to a self molecule, an MHC molecule
– the TCR binds to a complex of MHC mol and epitope peptide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

in terms of MHC how is antigen recognised

A

-different pathways for antigen presentation by MHC
-MHC I for intracellular antigens CD8 T cells
-MHC II for extracellular antigens CD4 T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how T cells orchestrate cell mediated immunity and regulate B cell responses to most antigens

A

-virus infects cell
-viral proteins synthesised in cytosol
-peptide fragments of viral proteins bound by MHC I in ER
-bound peptides transported by MHC I to cell surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how is antigen recognised in regards to haplotypes

A

-diversity in MHC haplotypes within pop
-increases range of peptides presented to immune system within species
-reduces chance of pathogen invading immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what affects antigen recognition and how

A

MHC polymorphism affects antigen recognition by t calls by influencing both peptide binding and contacts between TCR and MHC mol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly