Cells

AMs were harvested by performing bronchoalveolar lavage (BAL) on C57BL/6J mice using 20mls of supplemented Dulbecco's Modified Eagle Medium (DMEM) (89% DMEM, 10% fetal bovine serum, 1% pen-strep, and 5mM EDTA) as described in²². To prepare RNA from interstitial cells, lungs were homogenized in TRIzol (Thermo Fisher Scientific; Waltham, MA) after BAL using a tissue homogenizer (OMNI International; cat# Th115). BMDMs were obtained by flushing bone marrow cells from the femur and tibia of C57BL/6J mice as explained in ⁴⁶ . Briefly, bone marrow cells were incubated at 37^°C in 5% CO₂ for 7 days in BMDM differentiation media (59% Iscove's Modified Dulbecco's Medium (IMDM), 30% L-929 cell supernatant, 10% fetal calf serum (FCS), and 1% Pen-Strep). Human AMs were collected by ex-vivo BAL of human lungs that were not used for transplant. Human monocyte-derived macrophages were harvested by gradient centrifugation with the use of Ficoll-Paque Plus (GE healthcare) from peripheral blood of healthy donors followed by differentiation with human recombinant colony stimulation factor-1 (50ng/ml; R&D System, Minneapolis, MN) for 7 days.