Immunology Exam 1 Lecture 2 Concepts

Front 1

What are the first lines of defense against infection?

Back 1

Physical defenses, chemical defenses, antibacterial peptides, and antiviral proteins

Front 2

How does the innate immunity respond to a second infection as opposed to the first?

Back 2

The same way it responded to the infection the first time around.

Front 3

How many immunogens does the innate immunity target?

Back 3

All. It’s non-specific.

Front 4

Does everyone have innate immunity?

Back 4

Yes.

Front 5

What is the adaptive immunity mediated by?

Back 5

Lymphocytes and their products

Front 6

What do antibodies do?

Back 6

Block infections and eliminate microbes.

Front 7

What eliminates intracellular microbes?

Back 7

T lymphocytes

Front 8

What are the routes of infection for pathogens?

Back 8

Mouth, respiratory tract, GI tract, reproductive tract, external epithelia (physical contact, wounds and abrasions, and insect bites), and opportunistic pathogens.

Front 9

What is the protective immunity against extracellular infections in the interstitial spaces, blood, or lymph?

Back 9

Complements, phagocytosis, antibodies

Front 10

What is the protective immunity against pathogen infection on the epithelial surfaces?

Back 10

Antimicrobial peptides, antibodies (IgA)

Front 11

What is the protective immunity against cytoplasmic pathogen infections?

Back 11

NK cells, cytotoxic T cells

Front 12

What is the protective immunity against vesicular pathogen infections

Back 12

T cells, NK cell dependent macrophage activation

Front 13

What are the three major interfaces between the body and the external environment?

Back 13

Skin, GI tract, respiratory tract

Front 14

How do microbes enter the host from the external environment?

Back 14

Via the 3 major interfaces by physical contact, ingestion, and breathing

Front 15

What is one of the most important barriers to infection, and why?

Back 15

The skin. Direct inhibitory effects of lactic acid and fatty acids in sweat and sebaceous secretions and the lower pH

Front 16

What can cause a major problem in our mechanical defenses?

Back 16

Skin loss

Front 17

What does mucus do?

Back 17

It is a protective barrierbecause it keeps the bacteria from adhering to the epithelial cells.

Front 18

What is a goblet cell?

Back 18

A cell with a ‘notch’ in it to be able to capture whatever pathogen is attempting to get in, and move it to the cilia to be directed out of the body

Front 19

Where do goblet cells reside?

Back 19

Bronchial ciliated epithelium

Front 20

How do cilia remove microbes?

Back 20

Forcing you to cough and sneeze

Front 21

What would happen in a patient without functioning cilia?

Back 21

Recurring respiratory tract infections

Front 22

What are surfactants?

Back 22

The main defenses in the lower respiratory tract that are secreted by specialized cells lining the alveoli that contain pathogen binding proteins (members of the collectin family)

Front 23

What are collectins?

Back 23

Globular lectin like heads that bind to sugars on microbes and long collagen like tail that bind to phagocytes or complements. They have a pattern recognition role.

Front 24

What is one of the main defenses against infection of the gut?

Back 24

Low pH

Front 25

What happens to patients who are unable to secret gastric acid?

Back 25

High risk for salmonella infections

Front 26

What are microbiological defenses?

Back 26

Trillions of communalistic bacteria which suppress the growth of pathogenic bacteria and fungi

Front 27

Why do commensals suppress pathogens?

Back 27

Physical advantage of previous occupancy (especially on epithelial surfaces), competition for nutrients, producing inhibitory substances

Front 28

What occurs if the commensals are disrupted?

Back 28

There’s an opportunity for pathogens to infect the gut

Front 29

The flushing action of tears, saliva, and urine are chemical defenses or mechanical defenses?

Back 29

Mechanical

Front 30

What do secreted body fluids contain?

Back 30

Microbicidal factors

Front 31

Where is lactoferrin and what does it do?

Back 31

It may reside in blood, and it depreives bacteria of iron and is bacteriostatic

Front 32

What is another name for antimicrobial peptides?

Back 32

Defensins

Front 33

What is the charge of antimicrobial peptides and why?

Back 33

+ charge to attract it to the transmembrane electric field and docks it into the lipid bilayer

Front 34

Are antimicrobial peptides hydrophobic or philic, and what does this accomplish?

Back 34

Amphipathic, and this allows it to interact with the membrane

Front 35

How do antimicrobial peptides kill microbes?

Back 35

They form pores in the membrane

Front 36

How are antimicrobial peptides activated?

Back 36

Proteases in neutrophils

Front 37

What type of defensins do neutrophils have?

Back 37

Alpha

Front 38

What kind of defensins does the respiratory tract produce?

Back 38

Beta

Front 39

Where are defensins primarily located?

Back 39

GI and lower respiratory tract

Front 40

What are some cells that produce pentraxins?

Back 40

Myeloid cells, endothelial cells, and epithelial cells.

Front 41

Where do pentraxins reside

Back 41

In blood and lymph

Front 42

What defenses do we have against viruses?

Back 42

Defensins

Front 43

How do defensins impact HIV?

Back 43

It binds to the CXCR4 receptor and blocks entry of virus into the cell

Front 44

How do defensins impact retroviral DNA?

Back 44

By binding to the apobec3g to cause hypermutation and inactivate the molecules

Front 45

What are produced by various cells upon infection?

Back 45

INFs

Front 46

What do interferons do?

Back 46

Induce resistance to viral replication in all cells, increase expression of ligands for receptors on NK cells, activate NK cells to kill virus infected cells

Front 47

How does an interferon inhibit viral replication?

Back 47

Activating intracellular enzyme pathways that degrade the viral genome and inhibit transcription of viral messenger RNA

Front 48

Define paracrine action

Back 48

The cell can have an affect on neighboring cells

Front 49

What is Type 1 IFN secreted by?

Back 49

A wide range of cells at frontline tissues (ex. Epithelial cells in the gut)

Front 50

What are the most efficient producers of type 1 IFN?

Back 50

Plasmacytoid dendritic cells

Front 51

What are the three barriers to prevent microbial infection?

Back 51

Physical, mechanical, and chemical

Front 52

What generates pores in the membrane of bacteria?

Back 52

Anitmicrobial peptides

Front 53

What are able to generate an antiviral state in cells that harbor receptors for them?

Back 53

Interferons.