Several of these filtered candidates were found to be secreted (C12orf49, COL10A1, FNDC4, ITLN2, MATN3, PDZD2, RS1, SCRG1, and ST6GALNAC5) making them potential candidate biomarkers useful for distinguishing IPF from pneumonitis. Here, ITLN2 is linked to idiopathic pulmonary fibrosis.