Immunology Exam 1 Material

Front 1

Name the six agents of infectious disease.

Back 1

prions, viruses, bacteria, fungi, protozoa, and helminths

Front 2

Describe the composition of prions.

Back 2

Abnormally folded cellular protein.

Front 3

How do prions replicate?

Back 3

Come in contact with a normal cellular protein and induces it to fold abnormally.

Front 4

Why do prions cause disease?

Back 4

Build-ups of prions cause fibrils (mini-fibers) to accumulate in and around nerve cells.

Front 5

Describe the composition of viruses.

Back 5

Nucleic acid base (RNA or DNA) enclosed in a caspid, or protein coat. Some are also covered by an outer lipid layer derived from the membrane of the host cell with inserted viral glycoproteins.

Front 6

How do viruses replicate?

Back 6

Bind to cell receptors. Enter via endocytosis. Uncoats to release nucleic acid. Transcribes/translates viral genes. Replicates nucleic acid and assembles into new virions and viral proteins. Releases from cell by either budding (using the cell membrane to make a new capsid) (host survives) or lysing host.

Front 7

Describe the composition of a bacterium.

Back 7

prokaryotic

Front 8

How do bacteria replicate?

Back 8

binary fission

Front 9

Describe the composition of fungi.

Back 9

yeast (single cell) or mold (hyphae)

Front 10

How do the two types of fungi replicate?

Back 10

yeasts bud, molds create hyphal extension

Front 11

Describe the composition of protozoa.

Back 11

eukaryotic cells

Front 12

How do protozoa replicate?

Back 12

variations of binary fisison

Front 13

Describe helminths.

Back 13

round or flat worms

Front 14

How do helminths reproduced?

Back 14

sexual reproduction

Front 15

What are the stages of the infectious cycle in an individual animal?

Back 15

Entry, replication, spread from site of entry, evasion of host defenses, damage to cells/tissues/organs, exit

Front 16

What is the difference between "colonization" and "infection?"

Back 16

"Colonization" does not cause tissue damage.

Front 17

Define the term "pathogen."

Back 17

Any infectious agent that can induce pathology (or disease); may be a parasite or a saprophyte.

Front 18

Define the term "pathogenicity."

Back 18

Refers to the capacity of an infection to induce pathology (or disease).

Front 19

What are some pathogens obligate intracellular pathogens?

Back 19

Intracellular pathogens are protected from many elements of the immune system that act in the blood or in tissue fluids.

Front 20

What three strategies does the immune system use?

Back 20

exclusion of pathogens, disposal of pathogens, sequestration of pathogens

Front 21

How are pathogens excluded from the body?

Back 21

epithelial cells, antimicrobial molecules coating epithelium, normal microbial flora inhibiting establishment of pathogens

Front 22

How are pathogens disposed and sequestered?

Back 22

1. recognition of pathogens
2. communication and coordination of the response to the pathogen via signaling molecules and direct, cell-to-cell interactions
3. destruction or sequestration of pathogens

Front 23

What is the bystander effect?

Back 23

Immune-mediated damage of host tissues that occurs as a consequence of attempts to control infection.

Front 24

What are some common veterinary practices involving immunology?

Back 24

vaccination, immunologic tests for diagnosis of infectious diseases, diagnosis and management of immune-mediated disease syndromes

Front 25

What are the two branches of the immune system?

Back 25

innate and adaptive

Front 26

Define "innate immunity."

Back 26

Recognition is based on molecular patterns that are common to a group of pathogens.

Front 27

Define "adaptive immunity."

Back 27

Recognition is based on precise arrangements of amino acids or polysaccharides that are unique to a species or even strain of pathogen.

Front 28

What is contained within the fluid layer of the epithelial surfaces that kills or limits the ability of incoming infectious agents to establish infection?

Back 28

commensal microorganisms

Front 29

What are PAMPs?

Back 29

(pathogen-associated molecular patterns) molecular structures unique to infectious agents, and unlike any molecules found in vertebrate organisms

Front 30

Give an example of viral PAMPs.

Back 30

-DNA/double stranded RNA in cytoplasm
-spike proteins
-capsid proteins

Front 31

What are PRRs?

Back 31

Pattern-Recognition Molecules. Host molecules that recognize PAMPs

Front 32

What are DAMPs?

Back 32

Damage Associated Molecular Patterns. Host molecules that are released when cells or tissues are damaged. (b/c of unscheduled cell death or stress)

Front 33

Name the four sentinel cells.

Back 33

macrophages, dendritic cells, mast cells, and epithelial cells

Front 34

What do sentinel cells do?

Back 34

Randomly positioned cells carrying PRRs (pattern recognition receptors) that detect presence of infectious agents and release signaling molecules to recruit and active innate immune mechanisms.

Front 35

Define cytokine

Back 35

-protein signaling molecules that control and coordinate host defense mechanisms.

Front 36

How do cytokines act?

Back 36

They bind to a receptor on the target cell and activate a programmed response in that cell.

Front 37

What are chemokines?

Back 37

--a group of cytokines that induce cells to migrate to a site.

Front 38

Name some chemical mediators (signaling molecules) that may be released from a sentinel cell in response to PAMPs or DAMPs.

Back 38

histamine, prostaglandin, leukotrienes, cytokines, or chemokines

Front 39

What are the three main actions triggered by the products of active complement proteins?

Back 39

initiate inflammation, recruit (chemotaxis) and activate (opsonization) phagocytes, and form pores in microbial membranes

Front 40

What are phagocytes?

Back 40

Cells that ingest and kill microorganisms.

Front 41

What are the two primary phagocytes?

Back 41

macrophages and neutrophils (eosinophils phagocytize helminth larvae)

Front 42

What are interferons?

Back 42

cytokines that have multiple actions in host defenses including: inhibiting viral replication and alerting other cells to the presence of pathogens

Front 43

What are the two divisions of adaptive immunity?

Back 43

humoral and cell-mediated

Front 44

Generally, how does humoral immunity work?

Back 44

Antibody-mediated immune response. Antibodies produced by B-lymphocytes.

Front 45

Generally, how does cell-mediated immunity work?

Back 45

Immune response mediated by T-lymphocytes.

Front 46

Where are lymphatic tissues found?

Back 46

lymph nodes, spleen, adjacent to epithelium of all mucosal surfaces

Front 47

Where do lymphocytes mature?

Back 47

Primary Lymphatic Organs/Tissues:
thymus (T-lymphocytes), cloacal bursa (B-lymphocytes in birds), bone marrow and small intestine (B-lymphocytes in mammals)

Front 48

Where do mature lymphocytes respond to antigens?

Back 48

Secondary Lymphatic Tissues:
lymph nodes, spleen, mucosal epithelium

Front 49

What do lymph nodes do?

Back 49

Lymphocytes enter lymph nodes via blood vessels and are filtered out via lymphatic vessels.

Front 50

What does the spleen do?

Back 50

Filters antigens that enter the blood using dendritic cells.

Front 51

What is MALT?

Back 51

Mucosa-Associated Lymphatic Tissues: -aggregates of lymphocytes, dendritic cells, macrophages, and others. First filter to capture antigens that enter at mucosal surfaces.

Front 52

What composition do most antigens have?

Back 52

protein or polysaccharide

Front 53

Are antigen receptors specific or general?

Back 53

HIGHLY SPECIFIC

Front 54

How does a B-lymphocyte recognize an antigen?

Back 54

Using an immunoglobulin receptor to recognize the antigen and then secrete antibodies in response.

Receptor is "Y" shaped.

Front 55

How do T-lymphocytes recognize antigens?

Back 55

Using TCRs (T-Cell Receptors). TCRs are not secreted.

Receptor is two vertical parallel lines.

Front 56

What microbial structure does the innate immunity recognize?

Back 56

PAMPs

Front 57

What microbial structures does the adaptive immune system recognize?

Back 57

antigens

Front 58

What does the innate immune system use to recognize PAMPs?

Back 58

PRRs (Pattern Recognition Receptors)

Front 59

What does the adaptive immune system use to recognize antigens?

Back 59

antibodies (humoral) and TCRs (cell-mediated)

Front 60

How are receptors distributed in the innate immune system?

Back 60

All over in sentinel cells.

Front 61

How are receptors distributed in the adaptive immune system?

Back 61

Receptors present on lymphocytes are unique to it and its daughter cells.

Front 62

Describe the specificity of the adaptive immune system.

Back 62

high

Front 63

Describe the specificity of the innate immune system.

Back 63

low

Front 64

How do cytokines contribute to the adaptive immune system?

Back 64

Helper T-cells release cytokines to recruit and activate other cells.

Front 65

Generally, how do both T and B lymphocytes respond?

Back 65

antigen recognition, lymphocyte activation, lymphocyte proliferation, lymphocyte differentiation into effector and memory cells

Front 66

Where can B lymphocytes recognize antigens?

Back 66

on cell surface

Front 67

Where can T lymphocytes recognize antigens?

Back 67

recognize protein antigens inside a cell by way of antigen-presenting cells (APCs) such as dendritic cells, macrophages and B lymphocytes

Front 68

How do B cells act as APCs?

Back 68

Bind to receptor on cell surface, internalize antigen, present it to T-lymphocyte

Front 69

What activates T lymphocytes?

Back 69

APCs

Front 70

What activates B lymphocytes?

Back 70

follicular helper T cells

Front 71

What term describes all subsequent responses after the immune system's initial response to an antigen?

Back 71

anamnestic responses

Front 72

What are the five classes of antibodies?

Back 72

IgM, IgD, IgG, IgA, and IgE

Front 73

By definition, how can humoral immunity be transferred?

Back 73

by plasma

Front 74

By definition, how can cell-mediated immunity be transferred?

Back 74

by immune T-lymphocytes (in genetically identical animals only)

Front 75

What functions can antibodies serve?

Back 75

To act as an antigen receptor for B cells (initially IgM), neutralization of antigen, complement activation, opsonization of a pathogen, antibody-dependent cellular cytotoxicity (ADCC) for antigens too large to be phagocytized, and mast cell activation (IgE)

Front 76

Which classes of antibodies neutralize pathogens?

Back 76

IgG, IgM, and IgA

Front 77

Which classes of antibodies activate the complement?

Back 77

IgM, and to a lesser degree, IgG

Front 78

Which classes of antibodies opsonize pathogens, to make them easier to phagocytize?

Back 78

IgG, IgM, and IgA

Front 79

Which class of antibodies performs ADCC (antibody-dependent cellular cytotoxicity) to help neutrophils, macrophages, and natural killer cells recognize pathogens?

Back 79

IgG

Front 80

Which classes of antibodies perform ADCC to help eosinophils recognize pathogens?

Back 80

IgG and IgE

Front 81

Which class of antibody activates mast cells to release histamines and other substances?

Back 81

IgE

Front 82

What are the two types of alpha-beta T cells?

Back 82

cytotoxic T cells and helper T cells

Front 83

What is the function of cytotoxic T cells?

Back 83

-to kill cells infected by intracellular pathogens.

Front 84

What is the function of helper T cells?

Back 84

-communication and regulation of adaptive immune responses.

Front 85

What is the function of type 1 helper T cells (Th1)?

Back 85

-activate macrophages, making them more effective at killing pathogens. Influence class of antibodies made by B cells.

Front 86

What is the function of type 2 helper T cells (Th2)?

Back 86

-to recruit and activate eosinophils, making them helpful in infections by helminths and certain protozoa and arthropods. Also influence class of antibodies made by B cells.

Front 87

What is the function of type 17 helper T cells (Th17)?

Back 87

-to defend against extracellular pathogens through activation of neutrophils.

Front 88

What is one downside to Th17 cells?

Back 88

Responsible for some auto-immune diseases.

Front 89

What is the function of regulatory T cells (Treg)?

Back 89

-regulate immune response; malfunction of Treg cells can lead to autoimmune disease.

Front 90

What are the two classes of Treg cells?

Back 90

Natural Treg (nTreg) and Induced Treg (iTreg)

Front 91

What is the function of iTreg cells?

Back 91

-to end immune response

Front 92

What is the function of nTreg cells?

Back 92

-inhibits immune response to self