Comparing murine lung resident alveolar Siglec-F(high) macrophages to CD11b(high) macrophages following bleomycin injury

Macrophages (MΦ) have been shown to contribute to fibrogenesis, however the underlying mechanisms and specific MΦ subsets involved remain unclear. Lung MΦ can be divided into two subsets: Siglec-Fhi resident alveolar MΦ and CD11bhi MΦ that primarily arise from immigrating monocytes. RNA-seq analysis was performed to compare these MΦ subsets during fibrosis. CD11bhi MΦ, not Siglec-Fhi MΦ, expressed high levels of pro-fibrotic chemokines and growth factors. C56BL/6 WT mice were treated intratracheally with bleomycin. 8 days later, CD64+Mertk+ MΦ were sorted into Siglec-F(high) and CD11b(high) subsets. SiglecF(high) MΦ from naïve mice were also sorted. RNA was isolated and RNA-seq was performed to compare MΦ subsets.