past exam 1

unit 1 - 9

What is the main role of dendritic cells in the immune response?

To activate T cells (or deactivate them in the case of tolerance)

What is the difference between primary and secondary immunodeficiency?

Primary - genetic

Secondary - acquired, usually due to an infection

What is antibody dependent cell cytotoxicity (ADCC)?

Antibodies triggering the release of secretory granules full of toxic enzymes

What is the role of the NK cell in the immune response?

“dysregulated self” - infected host cells (DNA damage or cancerous as well) are marked for destruction by NK

“missing self” - host cells express MHC class 1 but pathogens can hide it, NK cells detect the lack and kill the cell

“coated with antibodies” - kills cells that have already been coated with antibodies from other immune cells

What is elephantiasis? How is it treated?

symptoms: swollen legs and groin tissue (blockage from worms = no lymphatic drainage)

pathogen: Filaria (worm) in the lymphatic vessels from mosquito bites

treatment: Tetracycline (kils life support bacteria, worm dies a month later)

Why would the body have separate mucosal and system immune systems? Advantages? Disadvantages?

Why: most infections are in one place or the other (intestinal infections are usually not skin infections)

Advantage: Minimize damage to host by only activating one

Disadvantage: Nasty pathogen that infects both systems = activation of both takes time since they are activated separately

What is natural resistance?

Some species are naturally immune to some pathogens due to factors like anatomy

INF-gamma receptor deficiency: How does this lead to increased susceptibility to Mycobacteria?

INF-gamma: important for activating resting macrophages

Mycobacteria: not good at triggering PRR

Mycobacteria lives in macrophages but can’t really survive in activated macrophages

Unable to activate = can easily thrive and grow

Why would it make sense that Ficolin-1 is limited to secretory granules and not usually free in the serum?

Ficolin-1 bind to host sugars (sialic acid) to be flagged for destruction. If too common, host cells will be killed for no reason

How does complement activation lead to inflammation?

C3 → C3a (some inflammatory) and C3b

C5 → C5a and C5b (very inflammatory and attracts neutrophils)

C2 kinin is a vasodilator

Why would an immunodeficiency in C3 have a different effect than in C8?

C3: early in the cascade so lose MAC since all downstream steps are removed, lose opsonization (essentially blind to many common bacteria), very bad

C8: lose MAC since main job is to build the complex, not that bad just lose ability to drill hole in membrane of certain bacteria

What are DAMPS?

Danger associated molecular patterns: host proteins that indicate infection or damage to the host

How does the induction of apoptosis lead to protection from infections?

Bacteria/virus inside the cell is growing and has an escape plan to spread

• apoptosis divides the cell and reduces the nutrients available for the infection

• apoptosis “kills” the cell and stops the release of the pathogen

Why does an infection cause an increase in hematopoiesis?

Immune cells mostly come from the bone marrow and increase during infection

Inflammation, complement, kinin system, vasodilation: relate these terms in one to two sentences

When the body needs an inflammatory response, the body begins the complement cascade to release inflammatory agents, like C3a and C5b, and also begins to start the kinin system for a more powerful response. The kinin system and the cascade also use chemical vectors like bradykinin to increase vasodilation to increase blood flow and tissue permeability.

How would you test a person for leukocyte adhesion deficiency?

Roebuck window test: scratch the skin, cover the scratch with a glass “window” for 2, 4, 8, 12, 24 hr, stain the slide for immune cells

Results: should be large amount of immune cells but completely blank for deficiency

What are the four things needed to be a good immunogen?

1. foreign

2. high molecular weight

3. chemically complex

4. Presentable (peptide for MHC, lipid for MHC I b)

Why can an antigen have more than one epitope?

Antigens can be rather large so they have surface area to present many epitopes since they are much smaller

When a cell is “committed” and can’t become a previous type of cell:

A. Pluripotent

B. Differentiation

C. Terminal Differentiation

D. Stem Cell

Terminal differentiation

Most immune cells originate in:

A. Spleen

B. Thymus

C. Bone marrow

D. Thyroid

E. Brain

The bone marrow

Deficits in these cells that bind to MHC Class IB is associated with an increase in diabetes:

A. TH1 Cells

B. TH2 Cells

C. TH17 Cells

D. NK T Cells

E. B-1 B cells

NK T cells

Small compounds are filtered from the blood primarily which two organs / tissues: Bubble two choices

A. Thymus

B. Lymph Node

C. Liver

D. Spleen

E. Kidney

Liver and kidney

The main cell that travels from the tissue to the lymph node to activate an immune response is the:

A. Neutrophils

B. Dendritic Cells

C. Macrophages

D. Eosinophils

Dendritic cells

The macrophage receptor that binds to mannose is known as _______________.

A. Fc Receptor

B. Complement Receptor

C. Mannose Receptor

D. Lipid Receptor

E. Dectin-1

Mannose receptor

The proteins in the membrane that binds to LPS, or the one that binds to mannose are examples of:

A. DAMP

B. PRR

C. PAMP

D. DRR

E. LOL

PRR

The membrane attack complex consists of:

A. C3a, C5a

B. C3b, C5b

C. C5b, C6, C7, C8, C9

D. C1, C2

C5b, C6, C7, C8, C9

Bacterial DNA is most likely to be recognized by:

A. TLR2

B. TLR3

C. TLR4

D. TLR5

E. TLR9

TLR9

An enzyme sometimes incorporated into viral particles to degrade viral DNA is:

A. TACE

B. STING

C. TRIM21

D. APOBEC3G

E. PKR

APOBEC3G

C1 Inhibitor (C1 INH):

A. Prevents the membrane-attack complex.

B. All Host Cells. Displaces Bb from C3b, and C2a from C4b

C. Cleaves C3b and C4b.

D. Dissociates C1r-C1s from C1q

E. All immune cells and RBCs. Displaces Bb, and C2a from C4b

Dissociates C1r-C1s from C1q

A potent vasodilator is:

A. C3a

B. C2 kinin

C. C1q

D. C4a

E. C5a

C2 kinin

The immune system rarely responds to homopolymers. Why not?

A. They are too short

B. They are too long

C. They are too chemically simple

D. They are too chemically complex

E. They are not foreign enough

They are too chemically simple

Recognition of LPS (lipopolysaccharide) as a foreign molecule/antigen is first seen during an immune response in:

A. Passive Immunity

B. Innate Immunity

C. Adaptive Immunity

D. Herd Immunity

Innate immunity

Most acute phase proteins are produced in the:

A. Spleen

B. Thymus

C. Thyroid

D. Bone Marrow

E. Liver

Liver

Mature neutrophils are referred to as:

A. Bands

B. Segs

Segs

NLRP3 is seen as a critical step in the inflammasome of:

A. Necrosis

B. Apoptosis

C. ETosis

D. Pyroptosis

Pyroptosis

The main function of this cell is to be a pack-rat and hold antigen in the lymph node.

A. Neutrophil

B. Conventional Dendritic Cell

C. Basophil

D. Macrophage

E. Follicular Dendritic Cell

Follicular dendritic cell

Which deficiency is most likely to lead to more infections by Mycobacterium tuberculosis?

A. Factor I Deficiency

B. INF-γ Receptor Deficiency

C. C8 Deficiency

D. IRAK4 Deficiency

INF-γ Receptor Deficiency

NK cell – detection of the absence of MHC Class I

A. Dysregulated self

B. Stress-induced self

C. Missing self

D. Activated Self

Missing self

Tolerance is best described as:

A. The ability to recognize specific pathogens.

B. The ability to recognize molecular patterns

C. The lack of an immune response to pathogens.

D. The lack of immune response to the host.

The lack of immune response to the host

An antibody forms to amino acids 37-46 of a protein. This would best be described as a

A. Linear Epitope

B. Conformation Epitope

C. Isotypic Epitope

D. Immunogen

Linear epitope

The main “Scavenger” immune cell that cleans normal host tissue is:

A. Neutrophils

B. Dendritic Cells

C. Macrophages

D. Eosinophils

Macrophages

T Cells mature in the :

A. Thymus

B. Liver

C. Bone Marrow

D. Spleen

E. Germinal Center

Thymus

The part of the complement C1 protein that binds to the cell/antibody is known as:

A. C1p

B. C1q

C. C1r

D. C1s

E. C1t

C1q

Prevents the membrane-attack complex.

A. CD59 (Protectin)

B. Decay Accelerating Factor (DAF)

C. C1 Inhibitor (C1 INH)

D. MCP E. Ficolin

CD59 (protectin)

The immune response that only uses cells and factors already present in the tissue is the

A. Immediate Innate Immunity

B. Early Induced Response

C. Adaptive Immune Response

D. Natural Resistance

Immediate innate immunity

Mucus is moved to the stomach by:

A. Flagella

B. Peristalsis

C. Cilia

D. Nose Hairs

Cilia

Peptides that insert holes into fungal membranes:

A. Lactoferrin

B. Chitinase

C. Lysozyme

D. α-defensins

E. β-defensins

α-defensins

Often binds to certain gram positive bacteria

A. Lactoferrin

B. Chitinase

C. Interferon

D. Fibronectin

E. Siderophore

Fibronectin

LPS is often associated with:

A. Inhibition of Macrophages

B. Inhibition of Neutrophils

C. Activation of Septic Shock

D. Toxic Shock Syndrome

E. Tuberculoid Leprosy Infections

Activation of septic shock

The cell in the Peyer’s patch that brings antigen from the mucosal membrane to the dendritic cell is the:

A. B-1 Cell

B. M Cell

C. T Cell

D. Mast Cell

E. Macrophage

M cell

The movement of lymph in the lymphatic capillary is prevented from going backwards by:

A. Constant pressure

B. Heart Beats moving the fluid forward

C. Filaments that anchor it

D. Valves

E. It isn’t prevented from going backwards as can be seen by elephantiasis

Valves

The main T cells that kills virus infected cells are the:

A. Memory B Cells

B. Helper T Cells

C. Cytotoxic T Cells

D. All of the above

Cytotoxic cells

It is important to turn off the immune response

A. To prevent autoimmune disease

B. To prevent excessive host tissue damage

C. To induce tolerance

D. All of these

E. A and B

All of these

A sac of digestive enzymes inside the cell:

A. Lysozyme

B. Lysosome

C. Secretory Granules

D. Endosome

E. Mesosome

Lysosome

What is the function of C3b(H2O)Bb?

A. C3 convertase

B. C5 Convertase

C. Membrane Attack Complex

D. A and B

C3 convertase