TLR9 and pulmonary fibrosis: In another model of lung fibrosis, it was observed that the bleomycin induced lung fibrosis was similar between TLR9-/- and wild type mice; however, when bleomycin challenged wild type mice were intranasally administered with CpG-ODN, there was a reduction in lung fibrosis as compared to untreated bleomycin challenged wild type mice (Luckhardt et al., 2011).