In BAL samples comparing stable, BOS and RAS patients, no difference in gene expression (CD6, TAP1, CXCL9, CXCL10, INPP5D, ISG20, LCK, NKG7, PSMB9, RUNX3 and BASP1) was detected. Here, PSMB9 is linked to Buschke-Ollendorff syndrome.