Intracellular pathogen response Flashcards
what disease does shigella spp cause
dysentery
What does Yersinia spp cause
the plague
what are the three killers higher than Tb in the world?
Acute respiratory infection, diarrhoea disease and HIV
Mtb is a bacillus or a coccus ?
Bacillus - it is a acid-fast rod
Name one way in which Mtb can be transmitted and where it can be commonly found ?
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 )
Name three risk factors of contracting TB?
Poverty and unemployment
homelessness
alcoholism/ drug abuse
HIV co-infection
what is cachexia ?
it is the weakening and wasting of the body where the body will eats its own organs
what are some of the early symptoms of pulmonary Tb?
weight loss, cough ( these may contain red blood cells) and night sweats
name two pathological symptoms of TB?
caseating granulomas which are described as granules that look like cheese in the lungs and necrosis of the lung tissue leading to cavitation
What are FAP receptors attached to the Mtb and what do they bind to ?
FAP- fibronectin attachment protein and they bind to cholesterol rich regions on the phagocyte. the Mtb wants to get into the phagosome.
what does PIP3 do ?
PIP3 aids the maturation of the endosome in the phagocyte?
what is the job of the V-ATPase pump?
This is to make the phagosome more acidic as it matures
what is the job of lactoferrin ?
it causes nutrient deprivement of the bacteria as it starves them of ferrin irons.
name three hydrolases in the phagolysosome
lysozymes, phospholipases and proteases
what is the role of SapM from Mtb?
SapM hydrolyses PIP3 inhibiting phagosome maturation
Which membrane protein is present but ineffective on the endosome when infected with Mtb?
Rab5 is present but it fails to recruit the other proteins.
what is the role of PIM’s in halting the maturation of the phagosome in Mtb infection?
PIM’s cause the fusion of the phagosome with early endosomes so they don’t mature.
How does VitD aid the immune response ?
The binding of TLR’s to the bacteria causes the activation of the VitD pathway to produce antibacterial peptide cathelicidin.
Name 4 antimicrobial functions that are upregulated in macrophage activation
toxic oxygen radicals
toxic nitrogen radicals
lysosomal enzymes
number of granules
name 4 cytokines that are up regulated in macrophage activation
IL-12, TNF, IL-1 and IL-18
what is the role of IL-18 ?
can cause NKC’s and soem T cells to release IFN-gamma that activates macrophages and other T- cells
name the role of Il-1 ?
IL-1 causes the increase of adhesion molecules on epithelial cells that lead to the diapedisis of phagocytes
Name one role of IL-12 secreted by APC’s ?
IL-12 is an inflammatory cytokine and causes the recruitment of NK cells to the site of infection.
which cells can leave the lungs when infected with a pathogen ?
The dendritic cells can leave the lungs and travel to the lymph nodes but the macrophages remain in the lung.
Name one other reason why the dendritic cells produce a better immune response than macrophages?
They can maintain their MHC molecules for longer meaning they can interact with cells for longer
which cytokine released by CD4 cells causes the activation of CD8 cells?
IL-12
Which cytokine causes the differentiation of CD4 cells to TH1 cells?
IL-12 and IFN gamma for an intracellular response
Which cytokines cause the differentiation of the CD4 cells to TH2 cells?
IL-4 for an extracellular response. IL-4 - are associated with the promotion of IgE which is part of the allergic response
which type of response causes Lepromatus leprosy ?
a Th2 response as the body is not set up to deal with an intracellular pathogen.
what two signals do CD4 cells deliver to macrophages for activation ?
CD40 sensitises macrophages to IFN gamma and then they produce IFN gamma
