Inflammatory profile in the bronchoalveolar lavage (BAL) fluid. Sham (gray bars) and MTS exposed (bars with hatched lines). BAL was performed at the indicated time points and total BAL cells (A), mononuclear cells (B) and total amount of protein (C) was analysed. Error bars represent SEM, n = 5/group. 1: 6 weeks smoke. 2: 6 weeks smoke + 6 weeks break. 3: 12 weeks smoke. 4: 12 weeks smoke + 6 weeks break.