Cell mediated effector responses

Question 1

Humoral vs Cell - Mediated Immune responses

Is recognition of extracellular pathogens involved in cell - mediated immune response (CMI)?

Answer 1

No
- its humoral immune response

Question 2

Humoral vs Cell - Mediated Immune responses

Is recognition of intracellular pathogens involved in CMI?

Answer 2

Yes

Question 3

Humoral vs Cell - Mediated Immune responses

What are the 5 main intracellular pathogens that CMI is effective against?

Answer 3

Virus - infected cells
Intracellular bacteria
Intracellular fungi
Tumor
Graft rejection
- organ transplant

Question 4

Humoral vs Cell - Mediated Immune responses

What are the 4 cells involved in innate CMI?

Answer 4

NK cells
NKT cells
Macrophage
Granulocytes
- neutrophils
- eosinophils

Question 5

Humoral vs Cell - Mediated Immune responses

What are the 3 cells involved in adaptive CMI?

Answer 5

CTL ( Cytotoxic T lymphocyte )
Th1
Th2

Question 6

Humoral vs Cell - Mediated Immune responses

What is the function of CD4+ Th2?

Answer 6

Promote antibody production

Question 7

Humoral vs Cell - Mediated Immune responses

What is the function of CD4+ Th1?

Answer 7

Mediate DTH
Recruit additional effectors to site of inflammation
- macrophages

Question 8

Humoral vs Cell - Mediated Immune responses

What are the 3 signals for T cell activation?

Answer 8

Signal 1
- peptide - MHC complex <=> TCR - CD3 complex

Signal 2
- B7 of APC / target cells <=> CD28 of T cell

Signal 3
Cytokines
- autocrine
– IL - 2
- paracine
– IL - 12

Question 9

Humoral vs Cell - Mediated Immune responses

What does the 3 signals do to T cell?

Answer 9

Signal 1
- Activation

Signal 2
- Survival

Signal 3
- Differentiation

Question 10

Humoral vs Cell - Mediated Immune responses

Does naïve T cell or activated T cell has a three chain structure, high affinity IL - 2 receptor?

Answer 10

Activated T cell

Question 11

Humoral vs Cell - Mediated Immune responses

What is the function of CDLA - 4?

Answer 11

Inhibitory receptor for B7 molecules

Question 12

What are the 3 things that causes anergic T cell?

Answer 12

Absence of costimulatory signal
- e.g. B7

Presence of CTLA - 4 on T cell
- binds to B7 ( CD80/ CD86 )

Presence of PD - L1 ( ligand )
- binds to PD - 1 on T cell

Question 13

Humoral vs Cell - Mediated Immune responses

What are the cytokines required for CD4+ survival?

Answer 13

IL - 7
- remember IL - 3, 5 ,7 ,11
– IL - 3 = myeloid
– IL - 5 = eosinophil
– IL - 7 = lymphoid
— Also promotes memory CD4+ & CD8+ survival
– IL - 11 = megakaryocyte

Question 14

Humoral vs Cell - Mediated Immune responses

What are the cytokines required for CD8+ survival?

Answer 14

IL -7
IL - 15
- remember redundancy of IL - 2
- Also promotes memory CD8+ survival

Question 15

Humoral vs Cell - Mediated Immune responses

What is the difference between in immunological synapse in Th1 & Th2?

Answer 15

Th1
- Bull’s eye synapse
– Supramolecular activation cluster ( SMAC )

Th2
- Multifocal synapse

Question 16

Humoral vs Cell - Mediated Immune responses

What is in Th1 SMAC?

Answer 16

Central SMAC ( cSMAC )
- TCR - CD3 <=> MHC - peptide
- CD 28 <=> B7

Peripheral SMAC ( pSMAC )