Running Title: Correlation of Inflammation and Emphysema Corresponding author:

D ow nloaded from 2 Cigarette smoke (CS)-exposed mice have been used to model airway inflammation and emphesema in humans; however, the impact of exposure duration, sex, and strain differences in susceptibility to progression of airway inflammation and to emphesema are poorly investigated. The present study was designed to determine the association between inflammation and emphysema by exposing two strains of mice, C3H/HeN (C3H) and C57BL/6 (BL/6), to filtered air (FA) or CS for 10, 16, or 22 wks. Both genders and strains of CS-exposed mice developed pulmonary inflammation as characterized by cell counts in the bronchoalveolar lavage fluid (BALF) and the levels of matrix metalloproteinases (MMPs) in the BALF. CS exposure caused persistently higher number of BALF macrophages in C3H compared to BL/6 mice, while more BALF neutrophils and persistently highe