stolen from lena yum immunology exam 2 combined set

What cluster of differentiation marker is expressed only on T helper cells?

CD4

What Ig class binds to the Fc receptor on NK cells?

IgG

What is the name of the maturation process that occurs in the thymus to ensure that T Cells do not recognize self antigens?

Negative selection (aka Self Tolerance)

What T helper cell type seems to have a specific effector function against fungi?

Th17

What tissue or organ provides the thymus all of the T Cell precursor cells?

Bone marrow

What specific cell surface component on CTL differentiates it from a T helper cell?

CD8

If a T helper recognizes a parasite antigen what type of T helper would it be?

Th2

When a CTL kills a cell, it activates caspases in the target cell that cut up DNA. What is this process of cell death called?

Apoptosis

Superantigen once in circulation causes what devastating and possibly deadly disease?

Toxic shock syndrome

Which of the following are NOT expressed on the cells surface of a Treg cell?

a. IL-2Ra

b. MHCI

c. MHCII

d. CD4

e. Both b and d

MHCII

What type of immune cell produces a secreted protein effector that can activate complement?

a. T helper cell

b. Neutrophil

c. Eosinophil

d. Megakaryocyte

e. Plasma Cell

Plasma cell

After graduation from Thymus U, in what organ/tissue to mature naïve T Cells hang out?

a. Bone marrow

b. Liver

c. Lymph node

d. Skin

e. Both a and d

Lymph node

A T helper cell's primary role is to do which of the following?

a. Make Ig or immunoglobulin

b. Induce apoptosis in a target cell

c. Fix complement

d. Present antigen

e. Produce cytokines

Produce cytokines

Which marker(s) do CTL express?

a. CD8

b. CD4

c. B7

d. MHCII

e. All of the above

CD8

The cell surface molecule CD4 in the TCR complex mediates what process for the T Cell?

a. Gene activation

b. ADCC

c. Ig gene rearrangement

d. Binding to MHCII

e. Both b and c

Binding to MHCII

Directly after the initial stimulation of antigen recognition, costimulation offers a second signal to activate the T Cell. What two receptors/proteins are involved on the T Cell and APC?

a. TCR and MHC

b. IgG and FcR

c. C3b and C5

d. CD28 and B7 (CD80/86)

e. LFA1 and ICAM

CD28 and B7 (CD80/86)

The portion of an antibody that is recognized by specific cytotoxic cells in antibody-dependent cellular mediated cytotoxicity (ADCC) is which of the following?

a. Fab

b. Fc

c. chain

d. CDR

e. None of the above

Fc

Aside from being proinflammatory, IL-6 is considered what Th cell type cytokine?

Th2

MHCI can be greatly upregulated in response to this family of cytokines:

interferons

IL-10 and TGF𝛽 are made by what T helper cell type?

Treg

The cytokines listed above in 20 are anti-inflammatory, but also aid what immune system response?

Mucosal immune response

Which cytokine mentioned above is also a Th2 cytokine?

IL-10

Which of the following is a key feature of neutrophils during inflammatory responses?

a. Their persistence along with T cells is a hallmark of chronic inflammation

b. They spew their chromatin and trap bacteria

c. They are generally the last leukocytes to enter the site as they are important in the termination stage of the response

d. They present antigens to CD4 T cells and initiate memory responses

e. They polarize to M1 or M2 depending on which cytokines they are exposed to

They spew their chromatin and trap bacteria

Which of the following is not one of the classical signs of inflammation?

a. Itching

b. Swelling

c. Redness

d. Pain

e. Heat

Itching

A patient has a genetic defect in a gene encoding the Toll-like Receptor 4 (TLR4). They would likely be immunocompromised because of their inability to activate which transcription factor that is important for the production of many inflammatory factors?

a. CRP

b. PAF

c. PLA-2

d. NFkB

e. 5-LO

NFkB

If you wanted to prescribe an anti-inflammatory drug to specifically inhibit leukocyte homing and adhesion to gut mucosal vascular endothelium, which of the following would you choose?

a. Omalizumab (Xolair)

b. Mepolizumab (Nucala)

c. Natalizumab (Tysabri)

d. Vedolizumab (Entyvio)

e. Adalimumab (Humira)

Vedolizumab (Entyvio)

5-lipoxygenase (5-LO) inhibitors used to treat asthma block production of which of the following factors?

a. leukotrienes

b. prostaglandins

c. prostacyclins

d. thromboxanes

e. H2 receptors

Leukotrienes

Specialized cells that extend processes across the epithelial layer to capture antigen from the lumen of the gut are referred to as what?

a. Microfold (M) cells

b. Intraepithelial lymphocytes (IEL)

c. Intraepithelial dendritic cells

d. Peyer's patch macrophages

e. Plasma cells

Intraepithelial dendritic cells

A patient with a genetic deficiency that results in their T cells being unable to produce the cytokine TGFβ will likely also have a deficiency in the production of which of the following factors important in gut immunity?

a. IgA

b. Dendritic cells

c. M cells

d. Intraepithelial lymphocytes (IEL)

e. Eosinophils

IgA

Which of the following is an important feature of IgA that makes it especially well-suited for mucosal immunity?

a. It is especially good at promoting inflammation to fight ingested microbes

b. It can be transcytosed across the epithelium

c. It is a pentamer and therefore very good at binding soluble toxins in the gut lumen

d. It is very good at opsonizing bacteria and activating complement

e. It is prone to proteolysis

It can be transcytosed across the epithelium

Neonates are born with protective levels of which factor below that provides them protection from infection during their first few months of life?

a. IgA and IgM

b. Memory T cells

c. Memory B cells

d. Fetal oligodendrocytes

e. IgG

IgG

Lactadhedrin is a factor found in breast milk that protects against rotaviruses. It belongs to what class of protective factor?

a. Lysozymes

b. Cytokines

c. Glycosylated proteins

d. Oligosaccharides

e. Immunoglobulins

Glycosylated proteins

The tonsils contain lymphoid tissue that is located in which of the following main GALT locations?

a. Peyer's Patches

b. Waldeyer's Ring

c. Lamina Propria

d. Isolated Lymphoid Follicles

e. Tatooine Crypts

Waldeyer's Ring

Which of the following statements is true concerning immunoglobulins found in mucosal immunity?

a. TGFβ helps induce class switching to IgA

b. IgA is the most abundant immunoglobulin

c. sIgA is resistant to proteolysis

d. sIgA is anti-inflammatory

e. all of the above

All of the above

Naïve lymphocytes in a Peyer's patch give rise to effector cells that can preferentially migrate to other mucosal area because of what specific receptor interactions?

a. Integrin α4β7 on the effector cells binding to MAdCAM-1 on mucosal vascular endothelial cells

b. Beta-2 integrin LFA-1 on the effector cells binding to ICAM-1 on mucosal vascular endothelial cells.

c. Integrin α4β7 on the effector cells rolling on αEβ7 selectins on mucosal vascular endothelial cells

d. Cadherins on the effector cells binding to MAdCAM-1 on mucosal vascular endothelial cells

e. None of the above because cells activated in the Peyer's patch don't prefentially migrate to other mucosal areas

Integrin α4β7 on the effector cells binding to MAdCAM-1 on mucosal vascular endothelial cells

At some point following birth there is a drop in the levels of IgM that a baby receives from his/her mother passively while in the womb. As the baby builds up his/her own immunoglobulin levels, during what period is the baby most vulnerable to infection?

a. Birth to 3 months

b. Birth to 6 months

c. 3 months to 12 months

d. 3 months to 24 months

e. 6 months to 18 months

3 months to 12 months

Eosinophils

Protect against parasite/worm infections; somewhat enriched in chronic inflammation

Mast cells

Differentiate into macrophages; second major immune cell type recruited during inflammation

Basophils

Major involvement in initiation of inflammation, particularly in allergic reactions

Monocytes

Major producers of histamine and arachidonic acid

E-selectin and P-selectin

Mediate weak interactions between neutrophils and activated endothelium

CD31

Mediates diapedesis

What are Neutrophils?

Primary immune cell recruited to site of inflammation

ICAM-1 and ICAM-2

Mediate strong interactions between neutrophils and activated endothelium

CXCL8

Induces conformation change in integrins, strengthens binding between neutrophil and activated endothelium

Macrophage

Immune cell that initiates inflammation

What is NFkB

Major transcription factor for expression of proinflammatory cytokine genes

DAMPs/MAMPs

Used for initial detection of tissue damage and/or pathogens

TLRs

Receptors to activate NFkB

Pro-inflammatory cytokines

Molecules with various local and systemic effects that boost inflammation

What inhibits PLA2 and therefore

inhibits AA metabolism?

A. 5LO-inhibitors

B. NSAIDs

C. LTRAS

D. Glucocorticoids

Glucocorticoids

What do Th1 cytokines generally do?

Promote CELL-MEDIATED IMMUNITY against INTRACELLULAR pathogens; activate MACROPHAGES and CD8 T cells; pro-inflammatory

What do Th2 cytokines generally do?

Promote humoral immunity and responses against parasites; activate B cells, eosinophils, and IgE production

What do Th17 cytokines generally do?

Promote inflammation and recruit neutrophils to fight extracellular bacteria and fungi

What do Treg cytokines generally do?

Suppress immune responses, promote tolerance, and reduce inflammation

What do chemokines generally do?

Direct movement (chemotaxis) of immune cells to sites of infection

What do inflammatory cytokines generally do?

Amplify inflammation by activating leukocytes and endothelium

IL-2 - source and function

Made by Th1 cells

stimulates T cell proliferation and enhances NK/CTL activity

IFN-γ - source and function

Made by Th1, NK, CTLs;

activates macrophages, increases MHC I/II expression, pro-inflammatory

IL-12 - source and function

Made by APCs

drives Th0 → Th1 differentiation and increases IFN-γ production

Are Th1 cytokines pro- or anti-inflammatory?

Pro-inflammatory

IL-4 - source and function

Made by Th2 and mast cells

induces Th2 differentiation and IgE class switching

IL-5 - source and function

Made by Th2 and mast cells

activates eosinophils

IL-6 - source and function

Made by many cells

promotes B cell development, can be pro- or anti-inflammatory

IL-10 - source and function

Made by Th2, Treg, macrophages

anti-inflammatory, inhibits Th1 responses

What pathogens do Th2 cytokines target?

Parasites (helminths)

IL-17 - source and function

Made by Th17 cells

recruits neutrophils and drives inflammation

What pathogens do Th17 cytokines target?

Extracellular bacteria and fungi

Are Th17 cytokines pro- or anti-inflammatory?

Strongly pro-inflammatory

TGF-β - source and function

Made by Treg and other cells

anti-inflammatory, promotes IgA class switching and immune tolerance

IL-10 - role in Treg function

Suppresses inflammatory cytokines and immune responses

Are Treg cytokines pro- or anti-inflammatory?

Anti-inflammatory

IL-1 - source and function

Made by APCs

increases vascular permeability, activates leukocytes

TNF-α - source and function

Made by many cells (esp. macrophages)

Major inflammatory cytokine, causes ACUTE phase response and septic shock

IL-6 - role in inflammation

Stimulates acute phase response in liver; pleiotropic

What is a key feature of inflammatory cytokines?

Increase adhesion molecules and recruit immune cells

IL-8 (CXCL8) - function

Chemoattractant for neutrophils

What determines which cells chemokines recruit?

The chemokine receptor expressed on the target cell

Are chemokines pro- or anti-inflammatory?

Generally pro-inflammatory (recruit immune cells)

IFN-α and IFN-β - function

Antiviral; inhibit viral replication and increase MHC I expression

IFN-γ - role difference

More inflammatory; activates macrophages and promotes Th1 responses

What do CSFs (e.g., G-CSF, GM-CSF) do?

Stimulate production and function of myeloid cells (neutrophils, macrophages)

Are CSFs inflammatory?

Generally pro-inflammatory/supportive

Which cytokine can belong to multiple families?

IL-10 (Th2 and Treg), IL-6 (Th2 and inflammatory), IFN-γ (Th1 and inflammatory)

What is pleiotropy in cytokines?

One cytokine having different effects on different cells

What is redundancy in cytokines?

Multiple cytokines having the same effect

Which cytokine induces IgA class switching?

TGF-β

What enzyme do corticosteroids inhibit to reduce inflammation?

Phospholipase A2 (PLA2), preventing arachidonic acid release

What transcription factor is inhibited by corticosteroids?

NF-κB (reduces pro-inflammatory gene expression)

What is the overall effect of corticosteroids on gene expression?

Decrease pro-inflammatory genes and increase anti-inflammatory genes

Name common corticosteroids used as anti-inflammatory drugs.

Prednisone, dexamethasone, hydrocortisone, betamethasone

What pathway do NSAIDs target?

Cyclooxygenase (COX-1 and COX-2) pathway

What do NSAIDs decrease production of?

Prostaglandins, thromboxanes, and prostacyclins

Examples of non-selective NSAIDs.

Aspirin, ibuprofen, naproxen, indomethacin

Example of a COX-2 selective inhibitor.

Celecoxib

What are the three main effects of NSAIDs?

Anti-inflammatory, analgesic, antipyretic

How do NSAIDs reduce pain?

Block PGE2-mediated sensitization of pain receptors

How do NSAIDs reduce fever?

Inhibit PGE2 production in the hypothalamus

What is a major adverse effect of NSAIDs on the GI system?

Ulcers and bleeding

Why can NSAIDs cause kidney problems?

Inhibit prostaglandins needed for renal vasodilation