Exam 4 Study Guide

Front 1

List the 3 lines of host defenses and an example of each

Back 1

1. 1st line- covering of the mucus membranes. Skin

2. 2nd line- inflammation and phagocytosis. Phagocytes

3. 3rd Line- Memory and specific immune system. Humoral immunity

Front 2

List 3 components of the first line of defense

Back 2

1. Outer covering- skin

2. Flushing effect- sweat

3. Chemical barriers- acidity of sweat

Front 3

What is the role of normal biota as a first line of defense?

Back 3

Normal biota prevents overgrowth of "bad" microbes

Front 4

What is lysozyme and why is it important?

Back 4

This is an enzyme found in bodily fluids that is capable of destroying peptidoglycan, which is only found in bacteria.

Front 5

Name two major body compartments that participate in immunity, what they do, and their function,

Back 5

1. Lymph nodes- collect pathogens that are killed off by the second line of defense and present it to the naive lymphocytes located there.

2. Respiratory- mucus brings pathogens out, nasal hairs trap large molecules

Front 6

Name the 3 major lymphoid tissues we discussed

Back 6

1. Thymus- trains immature T cells

2. Bone marrow- matures B cells, produces T and B cells

3. Lymph nodes- concentrates dead pathogens and cells

Front 7

What are PAMPs and PRRs?

Back 7

PAMPs- Pathogen Associated Molecular Patterns, a pattern on the outside of pathogens that our body is able to recognize

PRRs- Pattern Recognition Receptor- identifies PAMPs

Front 8

List 3 major differences in how the 3rd line of defense differs from the other 2 lines of defense

Back 8

1. Specific

2. Has memory

3. Life-long

Front 9

List the 4 stages of a specific immune response

Back 9

1. Pathogen enters system

2. 2nd line kills the pathogen, brings it to lymph nodes

3. PMCs cut up the pathogen, put it on the outside of their cells, and present it to naive lymphocytes

4. Lymphocytes attempt to find a match, and when they do, they proliferate

Front 10

Compare and Contrast T and B cells

Back 10

T- matured in thymus, part of cell-mediate immunity, not released as antibodies

B- matured in bone marrow, part of humoral immunity, can be released as antibodies, need T cells for cell presentation

Front 11

What is the difference between a naive and matured lymphocyte?

Back 11

Naive- has never seen an antigen before

Matured- has seen and been matched to an antigen

Front 12

Describe the structure of a T and B cell

Back 12

Both- Y shaped, has light chains matched up with heavy chains, has a variable and constant region

B- can be attached to membrane, or secreted as an antibody

T- embedded in membrane, unable to be secreted

Front 13

List the characteristics of antigens that optimize their immunogenicity

Back 13

Able to be recognized as a pathogen by our immune system, composed of large molecules such as proteins that do not have repeating subunits (such as sugars)

Front 14

Describe how the body reacts to a superantigen

Back 14

The body sees this antigen as much more severe than it actually is, and mounts an immune response 100-1000x bigger than normal, also releases cytokines which can result in cell death

Front 15

Describe the steps of phagocytosis

Back 15

1. Phagocyte is attracted to bacteria

2. Bacteria adhere to phagocyte PRRs by their PAMPs

3. Vacuole is formed around bacteria during engulfment

4. Phagosome, a digestive vacuole results

5. Lysosomes fuse with phagosome, forming a phagolysosome

6. Enzymes kill and digest bacteria

7. Undigested particles are released

Front 16

Describe the steps of inflammation

Back 16

1. Injury occurs, then vasoconstriction occurs

2. Vasodilation and increased blood flow occurs= increased permeability and leakage of fluid into tissues

3. Edema and infiltration of the skin by neutrophils

4. Macrophages and lymphocytes repair the tissues

Front 17

What is diapedesis and why is it important in inflammation?

Back 17

AKA transmigration. The process of WBCs migrating out of the blood and into the tissues. This is important so WBCs can begin cleaning up the area

Front 18

What is the mechanism of fever?

Back 18

Circulating substances called pyrogens reset the hypothalamic thermostat to a higher setting, causing increased heat production. Fever causes damage and stops the growth of bacteria

Front 19

What are pyrogens, and where do they come from?

Back 19

These are molecules responsible for starting a fever during infection. Can be exogenous, and come from infectious agents, or endogenous, which are released during phagocytosis.

Front 20

List four antimicrobial proteins

Back 20

1. Interferon: produced by WBCs for defense against viruses

2. Complement: a system that consists of 30 blood proteins that work to destroy bacteria and certain viruses

3. Iron binding proteins- keep iron bound so microbes can't use it

4. Antimicrobial peptides- AMPS, short proteins that insert themselves into bacterial membranes

Front 21

What are the three major differences in the third line of defense versus the other defense mechanisms?

Back 21

The third line is:

1. Specific

2. Has Memory

3. Is life long

Front 22

List the four stages of a specific immune response

Back 22

1. You are infected with a novel pathogen

2. Your second line of defense kills the pathogen

3. The dead pathogen gets taken to the lymph nodes, where they are chopped up and put on the outside of the APCs and shown to the naive lymphocytes

4. The naive lymphocytes attempt to match to the pathogens and if they do, they proliferate

Front 23

List the characteristics of antigens that increase their antigenicity

Back 23

Have large molecules that are not repeating- good= proteins, lipoproteins bad= sugars

Front 24

What kinds of cells can act as antigen presenting cells?

Back 24

Dendritic cells, macrophages, and B cells

Front 25

Explain the role of cytotoxic T cells in apoptosis

Back 25

Cytotoxic T cells get attracted to certain cells, and release perforins which punch holes in the cells, and then release granzymes, which cause apoptosis of the cell

Front 26

Describe the titer in the first and second response

Back 26

In the first response, there is a latent period from infection to production of antibodies, then the antibodies build slowly and gradually, and then decrease. With the second response, there is a quick, sharp increase of antibodies

Front 27

What is the main goal of antimicrobial treatment?

Back 27

To destroy the pathogen with minimal harm to the host cells

Front 28

What is the perfect antimicrobial drug?

Back 28

No perfect drug- each has its own pros and cons

Front 29

What are the sources of the most commonly used antimicrobial drugs?

Back 29

Bacillus, streptomyces, penicillin, and cephaloproium

Front 30

Selective toxicity

Back 30

The idea that an antimicrobial drug can destroy the pathogen without harming the host

Front 31

What are the five major targets of antimicrobial drugs?

Back 31

1. Cell walls/ Peptidoglycan

2. Proteins/ Ribosomes

3. DNA/ RNA

4. Folic Acid Synthesis

5. Cell Membranes

Front 32

What are some broad spectrum antibiotics? And narrow spectrum antibiotics?

Back 32

Broad: Penicillin, Cipro

Narrow: Polymyxins

Front 33

Describe the role of beta-lactamases, and their role in antibiotic resistance

Back 33

Beta-lactamases cleave beta-lactam rings in half, rendering Penicillin useless. They are created naturally by other microbes to combat the antibiotics made naturally by penicillin.

Front 34

What are examples of beta-lactam antibiotics?

Back 34

Penicillin and cephalosporins

Front 35

What are common cell-wall antibiotics that are not in the beta-lactam class?

Back 35

Carbapenems

Front 36

What are the ribosomal targets of antibiotics that target protein synthesis?

Back 36

They stop the substrate from moving within the ribosome, stops translation, distorts the ribosome, blocks tRNA entry

Front 37

What is the cellular target of quinolones?

Back 37

DNA and RNA

Front 38

Name two drugs that target the cell membrane

Back 38

Polymyxins and Daptomycin

Front 39

How does competative inhibition figure into the activity of sulfa drugs?

Back 39

You must give a large amount of Sulfa drugs, because they bind to and block the site of an enzyme that produces folic acid. If you don't have enough sulfa, it doesn't block the site

Front 40

What are two categories of Anti-fungal medication, and how do they work?

Back 40

1. Azoles- work by inhibiting ergosterol synthesis, which decreases membrane structural integrity

2. Griseofulvins- work by inhibiting cell division by messing with the microtubules

Front 41

List four anti-protozoa drugs

Back 41

1. Quinine

2. Chloroquine

3. Artemisinin

4. Metronidazole

Front 42

List three anti-Helminth drugs

Back 42

1. Mebendazole

2. Praziquantel

3. Albendazole

Front 43

What are three major modes of action of anti-viral drugs

Back 43

1. Block penetration of virus into the host cell

2. Blocks transcription and translation of viral molecules

3. Prevent maturation of viral particules

Front 44

What are the two types of antibiotic resistance?

Back 44

1. Acquired- bacteria are resistant to a drug which they were previously sensitive to, bacteria learn this from each other

2. Intrinsic- bacteria are resistant to any antibiotic that they produce

Front 45

Where does resistance come from?

Back 45

Has been around for longer than humans, comes because bacteria make antibiotics naturally to kill off other competative bacteria, who in turn make chemicals to make themselves resistant to the antibiotic

Front 46

What is a resistome?

Back 46

All antibiotic resistant genes

Front 47

How does drug resistance develop?

Back 47

By not finishing antibiotics- bacteria who have some resistance don't die, and share the resistance with others

Mass ABX prophylaxis in cattle

Addition to household products, creating resistance on our household surfaces

Front 48

Edema

Back 48

The leakage of vascular fluid into tissues

Front 49

Diapedesis

Back 49

Passage of blood cells through intact blood vessel walls during inflammation

Front 50

What process involves antibodies cross linking cells to make them bigger and easier to phagocytize?

Back 50

Agglutination

Front 51

True or false- Resistance genes can be transferred during transformation, transduction, and conjugation?

Back 51

True

Front 52

Are lymphocytes granulocytes?

Back 52

No

Front 53

What group do neutrophils, eosinophils, and basophils belong to?

Back 53

Granulocytes

Front 54

What lymphoid tissue has the function of filtering pathogens from the blood?

Back 54

Spleen