14 - Immune System & Cancer Flashcards
1
Q
Adaptive immune cells
A
- B cell
- T cell (cd4 and cd8)
- Antibodies
2
Q
Innate immune cells
A
- Mast cell
- Dendritic cell
- MAcrophage
- NK cell
- Granulocytes
- Complement protein
- IFNs
3
Q
Granulocytes
A
- Basophil
- Eosinophil
- Neutrophil
4
Q
Stress events in transformed cells that start IR
A
- Overexpress MIC molecules
- MIC binds NKG2D on NK cells
- NK cells releases perforin
5
Q
MHC 1
A
- Endogenous
- “inside out”
- Presents to CD8 T cells and DCs
6
Q
MHC 2
A
- Exogenous
- “outside in”
- Presents CD4 T cells and DCs
7
Q
Antigen presentation
A
- Peptide MHC 1 complex expressed on tumour cells
- Tumour antigens derived from intracellular protein
- Elimination by CD8 T cells
8
Q
CD28 ligand
A
CD80/86
9
Q
Signals in activation of T cells by APCs
A
- Signal 1: specificity (TCR recognizing MHC/peptide)
- Signal 2: activation/costimulatory (CD28 binding B7 or CD80/86 on APC)
10
Q
Absence of costimulatory signal
A
Leads to tolerance
11
Q
Presence of both signals
A
Activation
12
Q
Central tolerance
A
- Primary lymphoid organs e.g. thymus
- Strong recognition of self antigen leading to deletion
13
Q
Peripheral tolerance
A
- Periphery (blood)
- Strong recognition of self antigen leading to deletion, anergy or suppression (by Treg)
14
Q
Negative regulation of T cell activation
A
- Competitive inhibition of co-stimulatory signals (turn off signal)
- CTLA-4 out competes CD28 for binding to CD80/86
15
Q
Immune evasion techniques of tumours
A
- Low immunogenicity and antigen modulation (downregulation of MHC-1)
- Immune suppression (Tregs)
- Chronic antigen exposure leading to T cell dysfunction
