Defense Mechanisms of the Respiratory Tract - seminar 3.pptx

smoking and defense mechanisms of the respiratory tract

1. Smoking and Defense Mechanisms of the Respiratory Tract Malavika Murali MSc Organic Chemistry RA2232009010008

2. Contents 1. Mucociliary Blanket 2. Alveolar Epithelium 3. Alveolar Macrophages

3. Mucociliary Blanket This term refers to the self-cleaning lining which supports microscopically small hair-like filaments, called cilia R hythmically beat mucous through narrow sinus passageways towards the back of the nose and into the throat. Metachronal waves Goblet cells secrete viscous mucous which forms a layer over the cilia.

4. Alveolar Macrophages Macrophages  are a type of white blood cell that play an important role in the human  immune system I nvolved in e ngulfing and digesting microorganisms; clearing out debris and dead cells; and stimulating other cells involved in  immune function Macrophages form from monocytes, which themselves derive from the bone marrow.

5. The M1 type - detect, engulf and destroy bacteria. They can do this through phagocytosis,  The M2 type - play a role in  wound healing  and tissue repair, and have an  anti-inflammatory  role. 

6. Alveolar Epithelium Physical barrier that protects from environmental insults by segregating inhaled foreign agents and regulation water and ion transport.

7.   S erve many important functions including barrier protection, fluid balance, clearance of particulate, initiation of immune responses, mucus and surfactant production, and repair following injury. Type 1 cells - gaseous exchange Type 2 cells - surfactant, lamellar bodies

8. How does smoking affect the defense mechanisms of the respiratory tract The respiratory epithelium constitutes the first line of defense against inhaled pollutants and pathogens. Cigarette smoke can directly damage the airway epithelial barrier, including ciliated cells, goblet cells, basal cells, and submucosal secretory glands. Toxic substances in cigarette smoke, as well as nicotine containing electronic cigarettes (e-cigarettes), can impair the continuity of ciliary oscillation, and lead to mucus hypersecretion, delayed mucociliary clearance.

9. references 1.Pulmonary infections and Immunity, Chapter 227 - Defense Mechanisms of the Respiratory Tract, Raman G. Canto, George R. Robinson, Herbert Y. Reynolds. 2.The centres for advanced ENT care - The Mucociliary Blanket, filed under Nasal and Sinus, https://ent-md.com/the-mucociliary-blanket/ 3. National Library of Medicine, Histology, Alveolar Macrophages, Ahmed Naeem;  Sachchida N. Rai;  Louisdon Pierre .