Pulmonary Defense Mechanisms

Question 1

What are our pulmonary defense mechanisms?

Answer 1

1. Branching of Airways allows for deposition of material before vulnerable alveoli
2. Mucocilliary elevator and cough
3. Alveolar Macrophage

Question 2

What components makes up the airway epithelial fluid and help fight infection?

Answer 2

1. antimicrobial peptides
2. Antioxidants
3. Antiproteases
4. IgA
5. Low pH

Question 3

Hypersecretion of mucus can be seen In these 4 chronic airway diseases:

Answer 3

1. Chronic Bronchitis
2. COPD
3. Asthma
4. CF

Question 4

What is Kartagener’s syndrome? What conditions are associated with it?

Answer 4

Kartagener’s- Gene mutation causes:

• immotile cilia
• situs Inversus
• bronchiectaseis
• chronic sinusitis

Question 5

How does the lung discriminate harmful vs harmless material?

Answer 5

1. Size (small particles deposit in lower airways and are removed by escalator
2. Presence of PAMPs
3. Recognition by dendritic cells (they promote tolerance of common antigens at lymph nodes)

Question 6

A Bronchoalveolar Lavage would contain mostly which type of cell?

Answer 6

90-95% macrophages

Question 7

Explain the consequences of innate receptor signaling:

Answer 7

1. Suppression of inflammation (if harmless particle)
2. Inflammation (if harmful)

Question 8

What is the first leukocyte to migrate to an inflamed tissue?

Answer 8

PMNs (aka Neutrophil)

Question 9

True or False:

Innate inflammation, although beneficial, generally leads to scaring.

Answer 9

False:

Innate inflammation is a beneficial, non-specific response of tissues to infection and promotes immunity and generally leads to repair.

Question 10

True or False:

Macrophages suppress proinflammatory adaptive immune response.

Answer 10

True.

They want to resolve the inflammation.

Question 11

True or false:

Macrophages may also generate inflammation that can be harmful

Answer 11

True.

Alternatively programmed macrophages may lead to sarcoidosis granulomas and fibrosis.

Question 12

What is the major antigen presenting cell in the lung?

Answer 12

Dendritic cells

Question 13

True or false:

Cigarette smoking kills macrophages and decreases their number in the lungs

Answer 13

False:

Cigarette smoke increases alveolar macrophages to help clear out the crap.

Question 14

What effect does alcoholism have on the immunity of the lung?

Answer 14

1. Decreased mucociliary clearance
2. Impaired epithelial, macrophage, and T cell fxn