CTB6

Question 1

What is the primary function of the airway epithelium?

Answer 1

To act as a protective barrier and facilitate mucociliary clearance.

Question 2

What are the two main cell types in the airway epithelium?

Answer 2

Goblet cells (secrete mucus) and ciliated cells (move mucus).

Question 3

How does mucociliary clearance protect the respiratory tract?

Answer 3

It removes debris, pathogens, and particulates from the airway.

Question 4

What are goblet cells, and what do they secrete?

Answer 4

Goblet cells are epithelial cells that secrete mucins to form mucus.

Question 5

What are mucins?

Answer 5

High-molecular-weight glycoproteins that hydrate to form mucus.

Question 6

What are submucosal glands, and what is their function?

Answer 6

Glands in the airway submucosa that secrete mucus and antimicrobial molecules.

Question 7

What is the role of ciliated cells?

Answer 7

Ciliated cells beat rhythmically to propel mucus towards the pharynx.

Question 8

Why are ciliated cells metabolically active?

Answer 8

They require energy to maintain constant ciliary movement.

Question 9

How does smoking affect ciliated cells?

Answer 9

It impairs ciliary function, reducing mucociliary clearance.

Question 10

What is the basement membrane in the airway epithelium?

Answer 10

A thin layer of extracellular matrix supporting epithelial cells.

Question 11

How does airway remodelling occur in chronic respiratory diseases?

Answer 11

Through fibrosis, goblet cell hyperplasia, and smooth muscle hypertrophy.

Question 12

What causes goblet cell hyperplasia in asthma?

Answer 12

Chronic inflammation increases mucus production.

Question 13

How does mucus hypersecretion affect airflow?

Answer 13

Excess mucus narrows airways, increasing resistance.

Question 14

What is the role of tight junctions in the airway epithelium?

Answer 14

They maintain the barrier function by tightly linking epithelial cells.

Question 15

How do cytokines influence airway epithelial cells?

Answer 15

Cytokines promote inflammation and upregulate mucus production.

Question 16

What is the impact of oxidative stress on the airway epithelium?

Answer 16

It damages epithelial cells and impairs their barrier function.

Question 17

What is the role of antimicrobial peptides in the airway?

Answer 17

They help eliminate pathogens by disrupting microbial membranes.

Question 18

How does the airway epithelium respond to injury?

Answer 18

It undergoes repair processes involving cell migration and proliferation.

Question 19

What is epithelial-mesenchymal transition (EMT)?

Answer 19

A process where epithelial cells gain mesenchymal properties, contributing to fibrosis.

Question 20

What is the function of the respiratory basal cells?

Answer 20

They act as progenitor cells, regenerating damaged epithelium.

Question 21

How does inflammation impact the airway epithelium?

Answer 21

It disrupts tight junctions, increases permeability, and promotes remodelling.

Question 22

How does mucus composition change in chronic disease?

Answer 22

It becomes more viscous and harder to clear.

Question 23

What is the role of surfactant proteins in the airway?

Answer 23

They reduce surface tension and play a role in innate immunity.

Question 24

What mechanisms protect the airway epithelium from infection?

Answer 24

Mucociliary clearance, tight junctions, antimicrobial peptides, and immune cell recruitment.

Question 25

What happens to airway smooth muscle in asthma?

Answer 25

It undergoes hypertrophy and hyperresponsiveness.

Question 26

What are the main inflammatory cells in asthma?

Answer 26

Eosinophils, mast cells, and Th2 lymphocytes.

Question 27

How do allergens trigger airway inflammation?

Answer 27

Allergens bind to IgE on mast cells, causing degranulation and mediator release.

Question 28

How does neutrophilic inflammation differ in COPD?

Answer 28

Neutrophils dominate, releasing proteases that damage alveolar walls.

Question 29

What role do fibroblasts play in airway remodelling?

Answer 29

They deposit extracellular matrix proteins, leading to fibrosis.

Question 30

How does the airway epithelium sense environmental insults?

Answer 30

Through pattern recognition receptors (PRRs) that detect pathogens.

Question 31

What are toll-like receptors (TLRs)?

Answer 31

PRRs that activate immune responses upon pathogen recognition.

Question 32

How does hypoxia affect the airway epithelium?

Answer 32

It increases epithelial permeability and promotes inflammation.

Question 33

What are the key features of chronic bronchitis?

Answer 33

Mucus hypersecretion, goblet cell hyperplasia, and chronic inflammation.

Question 34

How does the airway epithelium adapt to increased pollutant exposure?

Answer 34

It increases mucus production and antioxidant defences but may become damaged over time.

Question 35

What is the role of dendritic cells in the airway?

Answer 35

They capture antigens and present them to T cells to initiate adaptive immunity.

Question 36

How does cigarette smoke impact airway epithelial repair?

Answer 36

It inhibits basal cell proliferation and repair mechanisms.

Question 37

What is the significance of epithelial barrier integrity?

Answer 37

It prevents pathogen entry and limits inflammatory responses.

Question 38

How does IL-13 contribute to airway remodelling?

Answer 38

IL-13 induces goblet cell hyperplasia and mucus production.

Question 39

What is the role of protease inhibitors in the airway?

Answer 39

They prevent tissue damage by inhibiting proteases released during inflammation.

Question 40

How does asthma differ from COPD in epithelial changes?

Answer 40

Asthma involves eosinophilic inflammation and reversible changes, while COPD involves neutrophilic inflammation and permanent damage.

Question 41

What are the effects of long-term oxidative damage on the airway?

Answer 41

It promotes epithelial senescence, remodelling, and loss of function.

Question 42

How does IL-4 influence airway inflammation?

Answer 42

It promotes Th2 responses, leading to IgE production and eosinophilic inflammation.

Question 43

How does the airway epithelium contribute to innate immunity?

Answer 43

By producing antimicrobial peptides, cytokines, and chemokines.

Question 44

How does mucus composition differ in cystic fibrosis?

Answer 44

It becomes dehydrated and thick due to defective ion transport, impairing clearance.

Question 45

What is airway hyperresponsiveness?

Answer 45

An exaggerated bronchoconstrictor response to stimuli.

Question 46

How do corticosteroids improve airway epithelial function?

Answer 46

They reduce inflammation, restoring barrier integrity and reducing mucus production.

Question 47

What is the role of interleukin-33 (IL-33) in asthma?

Answer 47

It activates innate lymphoid cells, enhancing airway inflammation.

Question 48

What happens during epithelial shedding in asthma?

Answer 48

Damaged cells detach, exposing underlying tissue and worsening inflammation.

Question 49

What are the long-term effects of airway remodelling?

Answer 49

It leads to irreversible airflow limitation and chronic respiratory symptoms.