Although the morphometric analysis of the lung parenchyma showed that the treatment with rBmTI-A did not control the increase in macrophages either before or after the development of emphysema, we observed that the treatment with this inhibitor was sufficient to prevent an increase in the number of MMP-12 positive cells when it was administered 1 h after the emphysema induction by PPE nasal instillation. The gene discussed is MMP12; the disease is pulmonary emphysema.