Cellular Communication And Humorl Immunity

Question 1

Mutation in CD40L causes

Answer 1

Hyper-IgM syndrome: B cell cannot switch from production of initial IgM to other types of immunoglobulins b/c w/o CD40L/CD40 b-cells cannot isotope switch

Question 2

Major function of CD28

Answer 2

Activation of naive T cells

CD28 is a receptor on T cells that needs to be engaged by its ligand (CD80 or CD86) on APCs to be fully activated

Question 3

Function of CTLA-4

Answer 3

Inhibition of T-cell activation

This is a regulatory protein

CTLA-4 competes with another protein, CD28, for binding to ligands (CD80 and CD86) on antigen-presenting cells. When CTLA-4 binds to these ligands, it sends inhibitory signals to T cells, suppressing their proliferation, cytokine production, and cytotoxic activity

Question 4

Function of B7-1 (CD80) or B7-2 (CD86)

Answer 4

Presented on an APC this will bind to either CD28 or CTLA-4 on a T-cell

CD28 is a receptor on T cells that needs to be engaged by its ligand (CD80 or CD86) on APCs to be fully activated. CD80 and CD86 are both ligands for CD28

CD8 = activation of naive t-cell
CTLA-4 = inhibition regulatory protein

The outcome of T cell activation is influenced by a balance engagement of activating and inhibitory receptors of the CD28 family

Question 5

Which cytokine produced in mucosal tissue activate IgA?

Answer 5

TGF-B, BAFF

Question 6

Which cytokine produced activates IgE?

Answer 6

IL-4

Question 7

Which cytokine produced activates IgG?

Answer 7

IFN-y

Question 8

Source cell for IL-2 and function

Answer 8

T cells
Proliferation and differentiation into effector T cells and memory T cells cells. ALSO promotes Regulatory T cells

Question 9

Source cell for IL-4 and function

Answer 9

-CD4 T cells (Th2 and Tfh)
-mast cells

-isotope switching for B-cells to IgE
-Th2 differention and proliferation for T-cells
-activation and/or inhibition of IFN-y

Question 11

Source cell for IL-6 and function

Answer 11

-MC
-DC
-T- cells
-Endothelial cells

-Th17 differention for T-cells
-AB production for B-cells
-syn. Of acute phase proteins in the LIVER

Question 12

Source cell for IL-9 and function

Answer 12

-CD4 T cells

-survival and activation of mast cells, b and T cells

Question 13

Source cell for IL-12 and function

Answer 13

-MC
-DC

-Th1 differentiation in T cells
-IFN-y synthesis, and increase cytotoxic activity in NK and T cells

Question 14

Source cell for IL-13 and function

Answer 14

-CD4 (Th2)
-mast cells

-isotope switching to IgE
-increase mucus production in epithelial cells
-alternative activation of MC

Question 15

Source cell for IL-15 and function

Answer 15

-MC

-Proliferation of NK cells
-survival and proliferation of CD8 t

Question 16

Source cell for IFN-alpha and function

Answer 16

-plasmacytoid DC
-MC

-antiviral state, and increase class 1 MHC expression in all cells
-activation of NK cells

Question 17

Source cell for IFN-Beta and function

Answer 17

-fibroblasts
-plasmacytoid DCs

-antiviral state, and increase class 1 MHC expression
-activation of NK

Question 18

Source cell for IFN-gamma and function

Answer 18

-T- cells (Th1, CD8)
-NK
-ILC1s

-classical activation of macrophages
-isotope switching in B-cells
-Th1 differentiation of T-cells
-increase expression of class 1 and class 2 MHC molecules

Question 19

Source cell for IL-10 and function

Answer 19

-Macrophages
-T cells (Treg)

-ant-inflammatory
-inhibition of expression of IL-12, costimulators, and class 2 MHC in Macrophages and DC

Question 20

Source cell for TNF and function

TNF, also called TNF-alpha; TNFSF2

Answer 20

-Macrophages
-NK cells
-T cells

-fever
-catabolism of muscle and fat
-activation of neutrophils, and endothelial cells (inflammation and coagulation)

Question 21

Source cell for IL-1a and function

Answer 21

-Macrophages
-DC
-fibroblast, endothelial cells, keratinocytes, hepatocytes

-activation of endothelial cells (inflammation and coagulation)
-fever

Question 22

Source cell for IL-1b and function

Answer 22

-Macrophages
-DC
-fibroblast, endothelial cells, keratinocytes,
-major type of biologically active IL-1

-activation of endothelial cells (inflammation and coagulation)
-fever
-synthesis of acute-phase proteins in the liver
-Th17 differentiation in T cells

Question 23

Source cell for TGF-B (transforming growth factor) and function

Answer 23

-T-cell (Treg)
-MC

-inhibition of proliferation and effector functions differentiation of Th17 and Treg
-inhibition of proliferation of B-cells, and inhibition of IgA production
-inhibition of activation of Macrophages
-increase collagen synthesis in fibroblast

Question 24

Cytokines in the pathogenesis of periodontitis

Answer 24

IL-23 stimulates Th17 (subtype of CD4 cell involved in perio)

Th17 releases
-IL-17
-IFN-y
-IL-6, IL-21

Question 25

Types of antibody response that results from T-dependent vs. T-independent

Answer 25

**T-dependent** -requires T/B cell interactions: specifically CD40/CD40L binding -isotype switching -high-affinity AB -requires protein antigens **T-independent** -mainly IgM production -polysaccharides, lipids, and other nonprotein antigens stimulate the AB production

Question 26

FcyRI on phagocytes bind to while FceR1 on phagocytes bind to

Answer 26

IgG1or IgG3 on the microbe Vs. IgE on the microbe (Mast cells/basophils/eosinophils degranulate when IgE bound to their Fc receptors (FceR1)

Question 27

In cell-mediates cytotoxicity, FcyRIII specifically presented on NK cells bind to

Answer 27

IgG ONLY IN CLUSTERED form

Question 28

In antibody-mediated clearance of Helminths which T cells stimulate Eosinophils?

Answer 28

Th2 cell (subtype of CD4) release IL-5 Then Eosinophils with FceR1 receptors bind to IgE Causing A release of granule content and Helminth death

Question 29

What is the most abundant complement protein in the plasma?

Answer 29

C3 B/c plays a role in all three pathways

Question 30

3 functions of the complement system

Answer 30

Opsonization Cell lysis Inflammation

Question 33

Cytokines for pro-inflammatory

Answer 33

TNF-alpha IL-1 IL-6