Lecture 18 Flashcards
(9 cards)
1
Q
What is the most common cause of community acquired pneumonia?
A
-infection due to Streptococcus pneumonia (gram positive bacterium)
2
Q
What are the first lines of defense against bacterial pathogens?
A
- intact epithelial lining
- alveolar macrophages
3
Q
TLR which binds to components of Gram positive bacteria (lipopeptides and peptidoglycan)?
A
TLR2
4
Q
TLR which binds to lipopolysaccharide on Gram negative bacteria
A
TLR4
5
Q
Function of alveolar macrophages?
A
- ingest and kill bacteria
- secrete pro-inflammatory cytokines
- recruit neutrophils to lungs
6
Q
Which two cells are phagocytic cells?
A
macrophages and neutrophils
7
Q
Which cytokines do macrophages recruit?
A
TNF, IL-1, and Il-8 to recruit and activate cells to infection site
8
Q
How do NETs (neutrophil extracellular traps) help kill pathogens?
A
- neutrophil extrudes DNA from nucleus to engulf pathogen
- proteins in nucleic acid of DNA have antimicrobial activity and expose bacteria to high local concentration of antimicrobial proteins
9
Q
What are potential mechanisms of lung injury?
A
- excess cytokine production cause damage to tissues and cells
- excess production of ROS and NO intermediates damage normal cells
- release of proteolytic enzymes
- disruption of epithelial barriers
- NET formation attacking normal cells
