Apoptotic clearance in rabbits with experimental pulmonary emphysema

In order to better understand pathogenesis of pulmonary emphysema, the model of experimentally induced pulmonary emphysema in Chinchilla rabbits was used for the estimation of apoptotic clearance of pulmonary tissue. Bronchoalveolar lavage was performed in three groups of animals: experimental group-E on hypercholesterolemic diet (4% edible oil solution of crystalline cholesterol), control group-C1 on standard diet for that animal species and animals on oily diet-C2. Apoptotic detection in cytocentrifuge preparations of lung washings was evaluated by in situ TUNEL. The property of alveolar macrophages to engulf apoptotic cells was estimated by light microscopy including 300 features (related subsequent steps: adsorption, internalization and intracellular processing of free apoptotic bodies) and was evaluated by scoring and indexing method. Internalization of apoptotic bodies by alveolar macrophages, as well as free apoptotic bodies were decreased in E compared to both C1 and C2 group (p is less than 0.01 and p is less than 0.05 respectively). Intracellular processing of apoptotic bodies by alveolar macrophages is significantly decreased in C2 in comparison with E (p is less than 0.05) and C1 group (p is less than 0.01). Apoptotic capacity of pulmonary tissue is significantly decreased in C2 in comparison with C1 group (p is less than 0.01). The results implicate that immuno-metabolic competence of pulmonary tissue might be essentially associated with tissue remodeling in pulmonary emphysema.