Lecture 12

Question 1

What is the linear theory for memory T cells?

Answer 1

Linear model: Come from effector cells that don’t die off after immune response is activated

Question 2

What is the branched theory for memory T cells?

Answer 2

Branched model: effector and memory cells have separate fates
T-bet –> effector cells
Blimp-1 –> memory cells

Question 3

What are the 3 memory T cell characteristics?

Answer 3

Last for years (most abundant in the body)
In peripheral tissue to respond to Ag
Have increased anti-apoptotic proteins (long survival)

Question 4

What are the 3 type of memory T cells?

Answer 4

Resident (Trm)
Central (Tcm)
Effector )Tem)

Question 5

Describe the characteristics of resident memory T cells. Where are they found and what do they produce?

Answer 5

Resident (Trm)

• In epithelium
• Produce IFN-y and TNF

Question 6

Where are central memory T cells found, what do they express, and what does Ag recognition lead to?

Answer 6

Circulate in blood and home to LN and spleen
-Express CCR7 and L-selectin

Ag recognition leads to the proliferation of more EFFECTOR cells

Question 7

Where are effector memory T cells found, do they proliferate, what do they produce, and what can they become if they enter the epithelium?

Answer 7

In blood
Do not proliferate
Produce IFN-y and TNF
Can become Trm cells if they enter the epithelium

Question 8

When are memory T cells generated during a humans lifetime?

Answer 8

Infancy, youth, young adult

Question 9

During adulthood are memory cells made? At what age does Senescence (stopping) of memory cells occur?

Answer 9

Few are made

65 years old

Question 10

What causes the conversion of naive T cells to become memory cells

Answer 10

Thymic involution leads to the conversion of naive T cells to memory cells

Question 11

What occurs at age 65 to cause the loss of proliferative capacity of memory cells from T cells?

Answer 11

Loss of CD28

Question 12

What are the stimulating cytokines for Th1 cells?

Answer 12

IL-12 and IFN-y

Question 13

What are the stimulating cytokines for Th2 cells?

Answer 13

IL-4

Question 14

What are the transcription factors found in Th1 cells?

Answer 14

T-bet

STAT4 and 1

Question 15

What are the transcription factors found in Th2 cells?

Answer 15

GATA3

STAT6

Question 16

What are the cytokines produced for Th1 cells?

Answer 16

IFNgamma

Question 17

What are the cytokines produced for Th2 cells?

Answer 17

IL-4. IL-5. IL-13

Question 18

What are the effector functions of Th1 cells?

Answer 18

Activate resident macrophages

IgG production

Question 19

What are the effector functions of Th2 cells?

Answer 19

Mast cell/eosin activation

IgE production

Question 20

What 3 roles are Th1 cells apart of?

Answer 20

Chronic infections
Autoimmune disease
IC microbes

Question 21

What 2 roles are Th2 cells apart of?

Answer 21

Helminth/parasite

Allergic disease

Question 22

What are the stimulating cytokines for Th17 cells?

Answer 22

IL-1, IL-6, IL-23, TGF-beta

Question 23

What are the transcription factors for Th17 cells?

Answer 23

RORyt

STAT3

Question 24

What cytokines are produced by Th17 cells?

Answer 24

IL-17

Question 25

What are the effector functions of Th17 cells?

Answer 25

NP, monocytic activation
-(maintenance of epithelial barrier)

Stimulate acute inflammation (IL-27)

Question 26

What 2 roles do Th17 cells play a part in?

Answer 26

EC bacteria

Autoimmune disease

Question 27

What are 2 important receptors found on T-reg cells and one transcription factor it produces?

Answer 27

** FOXP3+, CD3+, CD25+ **

Question 28

What transcription factor do T-reg cells produce? And why is this important?

Answer 28

FOXP3+ cells that have a HIGH TCR self-reactivity

It is important because T-reg cells help us maintain tolerant to self-antigens

Question 29

Describe the process of classical activation of macrophage resident cells.

Answer 29

Macrophage Resident Cell –> Production of Th1 cells and release of IFNy –> IFNy activates macrophages to have increased secretion of cytokines and increased phagocytic activity

Question 30

What are the 3 properties that are increased due to the classical activation of macrophage resident cells?

Answer 30

Increased killing of microbes
Increased Th1 production
Increased T cell activation

Question 31

Describe the process of alternative activation of macrophage resident cells.

Answer 31

Macrophage Resident Cell releases IL-4 –> Production of Th2 cells and release of IL-13, IL-4 –> Activates macrophage to release Il-10 and TGF-beta

Question 32

What are the 3 properties that are increased due to the alternative activation of macrophage resident cells?

Answer 32

Anti-inflammatory events
Wound Repair
Fibrosis

Question 33

What 2 cytokines do CD4+ T cells produce and what are their functions?

Answer 33

IL-2: Stimulates CTL differentiation

IFNy: Stimulates Macrophage resident cell to produce IL-12 which can help with CTL differentiation

Question 34

Describe the characteristics of y∂ T cells. Where are they found, what do they recognize, what do they produce, describe their diversity in relation to alpha-beta T cells, and are CD4 or CD8 molecules present?

Answer 34

Found in epithelium

Can recognize NON-PEPTIDE ags (PAMPS or DAMPS)

Rapid production of cytokines
-d/t presence of “pre-activated” status

Smaller diversity that alpha-beta T cells

No CD4 or CD8 molecules