Host Defense Mechanisms of the Lung Flashcards
upper airway and bronchi defense?
anatomic barriers cough mucociliary apparatus airway epithelium secretory IgA dendritic cells, lymphocytes, and neutrophils
alveolar space defense?
alveolar macrophage
immunoglobulins, opsonins, surfactants
lymphocyte mediated immunity
neutrophils and eosinophils
greater than 10 microns?
tonsils and adenoids
2-10 microns?
mucokinesis and coughing
less than 2 microns?
alveolar macrophages
cough reflex?
deep inspired
shut off air (close glottis)
expiratory effort, builds pressure
release high pressure trapped air
airway epithelial cells?
barrier function
- release bacterostatic molecules
- regulation of immune response
secrete IgA
**toll like receptors
secretory IgA
produced by plasma cells
- heterodimer
- secreted into lumen
**important for defense at mucosal surfaces
dendritic cells
trap antigen and present to other cells in lymphoid strictures
BALT
bronchial associated lymphoid tissue
GALT
gut associated lymphoid tissue
mucociliary clearance
2-10 microns deposited on mucus of upper airways
altered in asthma, chronic bronchitis, and cystic fibrosis
mucus contains?
IgA, lysozyme, lactoferrin, peroxidase
gel-on-brush model
propose model for mucus clearance
cystic fibrosis
mutant in CFTR gene
-cystic fibrosis transmembrane conductance regulator
-prevents chloride transport out of cell (Cl- and Na+ abnormalities)
accumulation of thick and viscous mucus - difficult to move it out (it is actually dehydrated)
increased risk of infecton
mucus in cystic fibrosis?
dehydrated**
normal - Kmucus less than Kpcl
dehydrated - Kmucus equals Kpcl
common pathogens in cystic fibrosis?
pseduomonas aeruginosa
burkholderia cepacia
staphylococcus aureus
haemophilus influenza
CFTR gene mutations?
pathogens can embed in mucus and survive in these suitable microenvironments
defense in alveoli?
IgA and IgG
surfactant, fibronectin, C reactive protein
lymphocyte antibody production
neutros and eosinos
protease/antiprotease in respiratory system?
neutrophil elastase
metalloproteinase
alpha-1 antitrypsin
imbalance can cause problems
epithelial cell recognition of pathogens?
ligation of toll like receptors
recognize flagellin, LP5, etc.
innate immune response?
dendritic cells
neutrophils
NK cells
adaptive immune response?
effector T cells
pathology of pneumonia?
lung inflammation associated with alveoli filling in response to lung infection
predisposing factors of pneumonia?
age - increases with age
immune status - immuno compromised
presence of lung disease - CF, chronic bronchitis
pneumonia?
V/Q mismatch
- vasoconstriction in edematous areas
- will develop hypoxemia
- CO2 levels should be fine
- pain with chest wall movement
no change amines?
dopamine
adrenaline
histamine
inactivated amines?
5-hydroxytryptamine
noradrenaline
activated peptide?
ANG I
-converted to ANG II in lung**
no change peptides?
ANG II
oxytocin
vasopresin
ANG 1 - 2
in lung**
inactivated peptides?
bradykinin
ANP
endothelins
activated arachidonic acid derivatives?
arachidonic acid
no change arachidonic acid derivative?
PGI2
PGA2
Inactivated arachidonic acid derivative?
PGD2, PGE2, PGF2a
inactivated purine derivatives
leukotrienes adenosine ATP ADP AMP
