Intracellular pathogen response

Question 1

what disease does shigella spp cause

Answer 1

dysentery

Question 2

What does Yersinia spp cause

Answer 2

the plague

Question 3

what are the three killers higher than Tb in the world?

Answer 3

Acute respiratory infection, diarrhoea disease and HIV

Question 4

Mtb is a bacillus or a coccus ?

Answer 4

Bacillus - it is a acid-fast rod

Question 5

Name one way in which Mtb can be transmitted and where it can be commonly found ?

Answer 5

Transmitted by aerosols, however you need high doses and lots of exposures to contract TB. It can be commonly found in congregate settings (close quarters such as prison )

Question 6

Name three risk factors of contracting TB?

Answer 6

Poverty and unemployment
homelessness
alcoholism/ drug abuse
HIV co-infection

Question 7

what is cachexia ?

Answer 7

it is the weakening and wasting of the body where the body will eats its own organs

Question 8

what are some of the early symptoms of pulmonary Tb?

Answer 8

weight loss, cough ( these may contain red blood cells) and night sweats

Question 9

name two pathological symptoms of TB?

Answer 9

caseating granulomas which are described as granules that look like cheese in the lungs and necrosis of the lung tissue leading to cavitation

Question 10

What are FAP receptors attached to the Mtb and what do they bind to ?

Answer 10

FAP- fibronectin attachment protein and they bind to cholesterol rich regions on the phagocyte. the Mtb wants to get into the phagosome.

Question 11

what does PIP3 do ?

Answer 11

PIP3 aids the maturation of the endosome in the phagocyte?

Question 12

what is the job of the V-ATPase pump?

Answer 12

This is to make the phagosome more acidic as it matures

Question 13

what is the job of lactoferrin ?

Answer 13

it causes nutrient deprivement of the bacteria as it starves them of ferrin irons.

Question 14

name three hydrolases in the phagolysosome

Answer 14

lysozymes, phospholipases and proteases

Question 15

what is the role of SapM from Mtb?

Answer 15

SapM hydrolyses PIP3 inhibiting phagosome maturation

Question 16

Which membrane protein is present but ineffective on the endosome when infected with Mtb?

Answer 16

Rab5 is present but it fails to recruit the other proteins.

Question 17

what is the role of PIM’s in halting the maturation of the phagosome in Mtb infection?

Answer 17

PIM’s cause the fusion of the phagosome with early endosomes so they don’t mature.

Question 18

How does VitD aid the immune response ?

Answer 18

The binding of TLR’s to the bacteria causes the activation of the VitD pathway to produce antibacterial peptide cathelicidin.

Question 19

Name 4 antimicrobial functions that are upregulated in macrophage activation

Answer 19

toxic oxygen radicals
toxic nitrogen radicals
lysosomal enzymes
number of granules

Question 20

name 4 cytokines that are up regulated in macrophage activation

Answer 20

IL-12, TNF, IL-1 and IL-18

Question 21

what is the role of IL-18 ?

Answer 21

can cause NKC’s and soem T cells to release IFN-gamma that activates macrophages and other T- cells

Question 22

name the role of Il-1 ?

Answer 22

IL-1 causes the increase of adhesion molecules on epithelial cells that lead to the diapedisis of phagocytes

Question 23

Name one role of IL-12 secreted by APC’s ?

Answer 23

IL-12 is an inflammatory cytokine and causes the recruitment of NK cells to the site of infection.

Question 24

which cells can leave the lungs when infected with a pathogen ?

Answer 24

The dendritic cells can leave the lungs and travel to the lymph nodes but the macrophages remain in the lung.

Question 25

Name one other reason why the dendritic cells produce a better immune response than macrophages?

Answer 25

They can maintain their MHC molecules for longer meaning they can interact with cells for longer

Question 26

which cytokine released by CD4 cells causes the activation of CD8 cells?

Answer 26

IL-12

Question 27

Which cytokine causes the differentiation of CD4 cells to TH1 cells?

Answer 27

IL-12 and IFN gamma for an intracellular response

Question 28

Which cytokines cause the differentiation of the CD4 cells to TH2 cells?

Answer 28

IL-4 for an extracellular response. IL-4 - are associated with the promotion of IgE which is part of the allergic response

Question 29

which type of response causes Lepromatus leprosy ?

Answer 29

a Th2 response as the body is not set up to deal with an intracellular pathogen.

Question 30

what two signals do CD4 cells deliver to macrophages for activation ?

Answer 30

CD40 sensitises macrophages to IFN gamma and then they produce IFN gamma