In emphysema, which protein imbalance contributes to lung tissue damage?

• A. Proteins from smoking
• B. Alpha-1 antitrypsin and elastase
• C. Collagen and elastin
• D. Immunoglobulins and cytokines

Answer: (B)

In emphysema, the imbalance between alpha-1 antitrypsin and elastase plays a central role in the pathology of the disease. Alpha-1 antitrypsin is a protein produced by the liver that protects the lungs from damage caused by enzymes like elastase, which is released by neutrophils during inflammation. Elastase breaks down elastin, an essential protein that maintains the elasticity and structure of lung tissue.

In emphysema, particularly in smokers or individuals with a deficiency of alpha-1 antitrypsin, the levels of elastase become elevated and go unchecked. This leads to excessive breakdown of elastin in the lung tissue, resulting in the characteristic loss of alveolar structure and function. This destruction of the alveoli reduces the surface area available for gas exchange, leading to the hallmark symptoms of emphysema, such as shortness of breath and reduced oxygenation.

Therefore, the correct answer highlights the critical role of the imbalance between these two proteins in the pathogenesis of emphysema, illustrating how a deficiency in protective mechanisms contributes to lung tissue damage.