Gene expression profiling on bronchoalveolar lavage (BAL) cells treated with all-trans-retinoic acid (ATRA)

All-trans retinoic acid (ATRA) is a potent retinoid, which has been used successfully in different clinical settings as a potential drug to treat COPD and emphysema. In alveolar macrophages, ATRA selectively down-regulates MMP-9 and up-regulates TIMP-1 expression. In the present study, we analyzed additional genes modulated by ATRA by performing mRNA expression array on alveolar macrophages after treatment with ATRA. Total RNA was isolated from BAL cells cultivated either in the presence of liposomal ATRA or left untreated for 3 days. Total RNA from five independent donors were pooled at 0.4 µg each to give a final amount of 2µg. This pooled RNA was used for microarray analysis using the Affymatrix array