Pulmonary Defense Mechanisms

Question 1

Removal mechanisms in the airways are aimed at?

Answer 1

MINIMIZING inflammation

Question 2

What are the main defense mechanisms in the upper airways and bronchi?

Answer 2

Anatomic barriers - epithelium
Cough reflex
Mucociliary apparatus
IgA

Question 3

What are the main defense mechanisms in the alveoli?

Answer 3

Alveolar macrophages
Type 1/2 Alveolar cells, Club cells
Surfactants and opsonins
Neutrophils

Question 4

What can trigger the cough reflex?

Answer 4

Chemicals, mechanical stimulation, inflammation and voluntary

Question 5

Describe the events of the cough reflex

Answer 5

1. Deep inspiration
2. Closure of the glottis to trap the air
3. Build up of intrathoracic pressure
4. Initiation of expiratory effort
5. Sudden release of trapped air at a higher pressure

Question 6

List 3 airway epithelium functions

Answer 6

1. Barrier function
2. Defense function - produce cytokines
3. Translocate IgA into the mucus at the lumen surface

Question 7

What size particles can be deposited in the mucus of the upper airways?

Answer 7

Greater than 2-3 micrometers and less than 10 micrometers

Question 8

What are some things that the mucus contains?

Answer 8

IgA, lysozyme, lactoferrin, peroxidases

Question 9

What are the 2 layers that the cilia on the airway epithelial cells traverse through to reach the foreign particles?

Answer 9

Sol (aqueous) layer

Mucus (gel) layer

Question 10

For the mucociliary apparratus, what do the cilia do?

Answer 10

They extend through the sol layer and the mucus layer to propel the foreign particles forward to attempt to expel them

Question 11

The upper airways also have a LARGE population of TRegs. What do they produce to minimize inflammation?

Answer 11

IL-10 and TGFbeta

Question 12

What is the alveoli’s first line of defense?

Answer 12

Alveolar macrophages

Question 13

What type of macrophages are alveolar macrophages and what is their job?

Answer 13

M2 - maintain tolerance

Question 14

What are the types of surfactant proteins found in the alveoli?

Answer 14

A and D

Question 15

List some of the jobs that SP-A and SP-D have in the alveolar spaces

Answer 15

1. Bind pathogens
2. Damage bacterial membranes
3. Modulate macrophage phagocytosis

Question 16

What do alveolar macrophages release to minimize inflammation?

Answer 16

IL-10 and TGFbeta

Question 17

If/when the acute inflammatory response begins, what cytokines are responsible for increasing the expression of adhesion molecules?

Answer 17

IL-1 and TNF

Question 18

With the acute inflammatory response, IL-1 and TNF increase adhesion molecules. What cell type slows down, binds to endothelium and enters?

Answer 18

Neutrophils

Question 19

What chemokine to neutrophils follow?

Answer 19

IL-8

Question 20

Neutrophils then deploy their ____ to catch bacteria

Answer 20

NETs

Question 21

If the acute inflammatory response turns to chronic, what cells will infiltrate?

Answer 21

Activated T cells

M1 macrophages

Question 22

The chronic inflammatory state brings T cells and M1s to the site. It also causes what 2 things?

Answer 22

1. Mucus HYPERsecretion

2. Remodeling of tissue – fibrosis

Question 23

What are the main molecular events that occur during the early phase of a Type 1 Hypersensitivity?

Answer 23

1. Cross-link mIgE

2. Degranulation of Mast cells

Question 24

What are the early phase symptoms of a Type 1 Hypersensitivity?

Answer 24

Sneezing
Pruritis
Rhinorrhea (runny nose)
Congestion

Question 25

What are the main cells that infiltrate the area during the late phase of a Type 1 Hypersensitivity?

Answer 25

``` Eosinophils Neutrophils Basophils Th2 lymphocytes MORE mast cells ```

Question 26

What are the 2 jobs of the eosinophils in the late phase of the Type 1 Hypersensitivity reaction?

Answer 26

1. Pro-inflammation | 2. Local tissue damage

Question 27

What are the late phase symptoms of a Type 1 Hypersensitivity?

Answer 27

Fatigue Myalgia Asthma

Question 28

What 2 things are responsible for chronic asthma remodeling?

Answer 28

Leukotrienes (C4, D4, E4) | Prostaglandins (D2, E2, F2)

Question 29

With chronic asthma remodeling, leukotrienes cause?

Answer 29

Bronchospasm Increased permeability Mucus production

Question 30

With chronic asthma remodeling, prostaglandins cause?

Answer 30

Bronchospasm | Vasodilation

Question 31

With chronic asthma remodeling what is deposited in the submucosa?

Answer 31

Collagen - by smooth m. cells and fibroblasts

Question 32

With COPD, what cytokine causes secretion of more cytokines?

Answer 32

Th17

Question 33

With COPD, Th17 causes secretion of?

Answer 33

IL-8, IL-17, IL-22

Question 34

With COPD, Th17 causes secretion of more cytokines that results in infiltration of what cells?

Answer 34

Neutrophils and inflammatory macrophages

Question 35

Ventilator Associated Lung Injury physical damage?

Answer 35

Over inflation | Mechanical stress

Question 36

Ventilator Associated Lung Injury biodamage?

Answer 36

Hyper-oxygenation Free radicals Increased Neutrophils

Question 37

With a Ventilator Associated Lung Injury, what do Neutrophil NETs lead to?

Answer 37

Platelet activation and clot formation

Question 38

Vaping Associated Lung Injury shows ______ on chest X-ray

Answer 38

Bilateral infiltrates

Question 39

Is there an infection with a Vaping Associated Lung Injury (VALI)?

Answer 39

NO

Question 40

What can a Vaping Associated Lung Injury turn into?

Answer 40

Lipoid Pneumonia

Question 41

With is Lipoid Pneumonia?

Answer 41

Pneumonia caused by inhaling lipids

Question 42

Besides a Vaping Associated Lung Injury, what else can cause Lipoid Pneumonia?

Answer 42

Chronic essential oil use