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🔍 Which cell type is responsible for producing this protein?
Dr. Shoaib Ahmad Baig
December 22, 2024
🔍 Question
Researchers conducted a study to investigate the protein composition of normal lung secretions. The study involved 20 healthy adults with no history of smoking or medication use. Bronchoalveolar lavage was performed to collect fluid samples, and a specific protein capable of degrading elastin in the extracellular matrix was identified.
Which of the following cell types is most likely responsible for producing this protein? |
Correct Answer 🎯: A. Alveolar Macrophages
⚙️
🧠Key Role: Immune defense and phagocytosis.
⬇
↑ Production of Elastase → Facilitates pathogen clearance.
⬇
🧠Found in bronchoalveolar lavage.
🧠Think of alveolar macrophages as “janitors” of the lungs → Use “cleaning tools” (elastase) to clear debris and pathogens.
• Non-macrophage cells are “specialized workers” → Focused on their specific tasks (mucus production, surfactant secretion, gas exchange) without ECM “cleaning tools.”
⚖️ Explanation of Other Differentials
Differential ⚖️ | Mechanism ⚙️ | Why Incorrect? 🔴 |
|---|---|---|
Ciliated Epithelium | Mucociliary clearance of debris | No elastase secretion; unrelated to ECM degradation. |
Club Cells | Secrete detox enzymes & surfactant-like material | Lack elastase activity; primarily involved in airway protection and regeneration. |
Goblet Cells | Mucus production → Trap particles | Secrete mucus, not elastase; no role in ECM degradation. |
Type I Pneumocytes | Gas exchange via thin epithelial barrier | Structural cells with no secretory function; no elastase production. |
Type II Pneumocytes | Surfactant production & repair | Surfactant secretion; no involvement in elastase activity or ECM degradation |
đź“ť Flashcards
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Dr. Shoaib Ahmad
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