CBG 26

Question 1

what does the faroe island case study show?

Answer 1

measle epidimic in 1781 then reintroductiom in 1848. later time round only old people that had memory cells survived. showed immunological memory can last a lifetime

Question 2

has polio been eradicated?

Answer 2

no nearly eradicated. eradicated after vaccine but problem due to MMR vaccinations diminishing.

Question 3

what are cytokines?

Answer 3

proteins that activate signalling pathways and regulate the immune response

Question 4

what 5 things make up innate immune response physical?

Answer 4

1) skin
2) eyes
3) respiratory tract
4) gastrointestinal tract
5) urogenital tract

Question 5

explain how skin works as an innate immune response in terms of mechanical chemical and micriobology?

Answer 5

sweat=flow of fluid off skin

SEBUM (fatty acids,lactic acids,lysozyme)

normal skin flora acts as barrier

Question 6

explain how eyes work as an innate immune response in terms of mechanical chemical and microbiology?

Answer 6

flow of fluid

tears have lysozymes

normal flora

Question 7

explain how respiratory tract works as an innate immune response in terms of mechanical chemical and micriobology?

Answer 7

flow of fluid an mucus by cilia and air flow

lysozyme in nasal secretions

normal flora

Question 8

explain how the gastro intestinal tract works as an innate immune response in terms of mechanical chemical and microbiology?

Answer 8

flow of fluid,mucus food and saliva

acidity and proteases

normal flora

Question 9

explain how the urogential tract acts as an innate immune response in terms of mechanical chemical and microbiology?

Answer 9

flow of fluid urine,mucus and sperm

acidity of vaginal secretions and spermine and zinc in semen

normal flora

Question 10

does the innate response size stay the same for primary and secondary response?

Answer 10

yes

Question 11

does the adaptive response stay the same for primary response and secondary response/

Answer 11

no secondary response is far larger

Question 12

What is an antigen?

Answer 12

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

Question 13

what is an epitope?

Answer 13

the part of an antigen molecule to which an antibody attaches itself

Question 14

what is an antibody?

Answer 14

a blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances that the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.

Question 15

what components make up the immune system? (4)

Answer 15

1 physical barriers
2 cells
3 soluble effector proteins (complement and antibodies)
4 cytokines (communication)

Question 16

describe immediate innate immunity (time frames)?

Answer 16

0-4 hrs
infection
recognition by broad non specific receptors
removal of infectious agent

Question 17

describe early induced innate response? time frames etc

Answer 17

4-96 hrs
infection
recognition by MICROBIAL ASSOCIATED MOLECULAR PATTERNS
inflammation,recruitment and activation of effector cells
removal of infectious agent

Question 18

describe adaptive immune response (time frames)?

Answer 18

late 96 hours + 
infection
transport of antigen to lymphoid organs
recognition by naive B and T cells
clonal expansion and differentiation to effector cells
removal of infectious agent

Question 19

all physical innate immune responses produce what 2 things?

Answer 19

all epithelial cellsare joint by tight junctions

all produce antimocrobial peptides called defensins

Question 20

what is the innate immune response initiated by? (3)

Answer 20

phagocytes
NK cells
soluble proteins

Question 21

talk about phagocytes. clue- macrophages and neutrophils are both phagocytes

Answer 21

Phagocytes are cells specialized in the process of phagocytosis. Phagocytosis=
capture, engulfment and breakdown of bacterial pathogens

Macrophages-Reside in tissues and recruit

neutrophils-Enter infected tissues in large numbers

Recognize common molecules of bacterial cell surface using a few surface receptors

Question 22

what are monocytes precursors to?

Answer 22

macrophages

Question 23

what does monocytes do?

Answer 23

Can be tissue resident or recruited to sites of inflammation

Engulf and kill viruses and bacteria

Important for antigen presentation to T cells

Question 24

what doe macrophages express lots of ? give 4 examples

Answer 24

receptors for microbial consituents
mannose receptor-for cell wall
scavenger receptor
LPS
TLr4-tol like-recognises dsRNA

Question 25

explain bacteria reaching macrophage endocytic receptors and signalling receptors.

Answer 25

If bacterium binds to Endocytic receptors of macrophages it induces their engulfment and degradation. If bacterial components bing to signalling receptors the macrophages induce the synthesis of inflammatory cytokines

Question 26

what do neutrophils do?

Answer 26

Highly motile, they respond rapidly to inflammatory stimuli by migrating out of the blood and into tissues in large numbers.

Recognise, engulf and kill viruses and bacteria.

Dead neutrophils are a major constituent of pus!

most common in early infection

Question 27

what is the complement system? which immune system is it part of?

Answer 27

a part of the immune system that helps or complements the ability of antibodies and phagocytic cells to clear pathogens from an organism.

It is part of the innate immune system, which is not adaptable and does not change over the course of an individual’s lifetime.

Question 28

after the bacteria has triggered macrophage signal receptors to release cytokines what happens?

Answer 28

more proteins/cytokines and chemokines
influx of neutrophiles
local redness and swelling (vasodilation and increased vascular permeability)
causing Inflammatory response.
Inflammatory cells migrate into tissue releasing mediators that cause pain

Question 29

define inflammatory response.

Answer 29

Accumulation of fluid and cells at infection site (swelling, redness, heat and pain)

Question 30

what is the acute complememnt and what does it enhance?

Answer 30

enhances phagocytosis.

Set of proteins which bind to bacterial surface

Question 31

how does the complement system work?

Answer 31

it is lots of small proteins in blood circulating as inactive pro-proteins.

stimulation= proteases cleave proteins to release cytokines

cytokines initiate further cleavage cascade

result= amplification of the response and activation of the cell-killing membrane attack complex.

Question 32

what is the complement system end result?

Answer 32

activation of the cell-killing membrane attack complex

Question 33

what are the complement basic functions?

Answer 33

Opsonization – enhancing phagocytosis of antigens (coats pathogens)

Chemotaxis – attracting Macrophages and neutrophils (ALERTS other components of immune system to danger)

Cell Lysis – rupturing membranes of foreign cells

Agglutination – clustering and binding of pathogens together (sticking)

Question 34

describe the 3 complement sytsem pathways briefly.

Answer 34

classical pathway- antigen-antibody complexes

MB-lectin pathway-lectin binding to pathogen surfaces

Alternative pathway-pathogen surface

Question 35

what do all 3 complement pathways lead to?

Answer 35

complement activation

Question 36

what is opsonization?

Answer 36

coating/flagging up antigens so that pathogens are more easily taken up by phagocytosis

Question 37

is innate immunity evolutionary early?

Answer 37

yes and it is the first line of defence against infection

Pre-existing or very rapid response (hrs)

Question 38

what is the complement system part of?

Answer 38

It is part of the innate immune system.However, it can be recruited and brought into action by the adaptive immune system.