Interferon-g or azathioprine plus corticosteroids do not alter the expression of apoptotic markers in alveolar macrophages of patients with IPF

Introduction: Pathologic apoptosis is described in IPF. Macrophage activation is implicated in the pathogenesis of fibrotic lung diseases. The apoptotic profile of alveolar macrophages (AM) in IPF is unclear. Aim: To examine the expression of apoptotic proteins in AM of patients with IPF after therapeutic intervention. Methods: Twenty newly diagnosed IPF patients were randomised in group A treated by a combination of interferonγ-1b and prednisolone and group B treated by azathioprine and prednisolone. Groups were compared regarding clinical deterioration, lung function, and bronchoalveolar lavage (BAL) apoptosis markers. We analyzed by immunohistochemistry, the expression of the anti- apoptotic markers bcl-2 and the pro-apoptotic markers bax, fas, fas ligand in AM obtained from BAL before and after treatment. We measured apoptosis by TUNEL. Immunohistochemistry results were evaluated with a digital image analysis assay. Results: No difference was observed regarding age, gender, smoking habit between the two groups of IPF patients. The patients of both groups had similar FEV1, FVC and DLCO values at entry and after six months of treatment. We found no difference in the expression of apoptotic markers in AMs before and after treatment between groups. We found no correlation between clinical and functional parameters and change in apoptotic markers. Conclusions: We specifically examined the expression of apoptotic markers in AMs of patients with IPF and we report that different treatment options do not affect the expression of these markers in IPF. These results may be related to the ineffectiveness of pharmacological therapies for IPF.