Mice were euthanized by intraperitoneal injection of pentobarbital sodium (150 mg/kg; diluted 1:2 with 0.9% NaCl physiological) and analyzed ~16 h after the last CS exposure. After perfusion of the heart with PBS, for whole lung analysis, lungs were directly collected into 1 mL PBS (2% FBS). Lungs were processed using the mouse lung dissociation kit (#130-095-927, Miltenyi Biotec) according to the manufacturer's instructions (program 37C_m_LDK_1). After termination of the program, C tubes (#130-093-237, Miltenyi Biotec) were detached from the gentleMACS dissociator and centrifuged shortly at 1500 rpm. Pellets were resuspended in the same supernatant and filtered through a 70 μm cell strainer (#CLS431751, Sigma-Aldrich) into a 50 mL tube. After centrifugation at 1500 rpm for 2 min, the supernatant was discarded and the pellets were resuspended with 1 mL ACK lysis buffer (#A1049201, Thermo Fisher Scientific) for 3-5 min. Again, the suspension was filtered through a 70 μm cell strainer (#CLS431751, Sigma-Aldrich) and spun at 1500 rpm for 2 min. The supernatant was discarded and cells were resuspended in 0.5-1 mL PBS (2% FBS) and used for subsequent flow cytometry experiments. Per experiment, 100.000 (12+8 weeks experiment) or 250.000 cells (4 and 12 weeks experiments) were FACS-sorted (Myeloid cells: viable CD45+ single cells; excluded CD11c/CD11b double-negative cells = considered as non-myeloid cells; AM: live CD45+CD11c+SiglecF+ cells). According to the manufacturer's instructions (Chromium Next GEM Single Cell 3' Kit v3.1 16 rxns PN-1000-268; Chromium Next GEM Chip G Single Cell Kit, 48 rxns PN- 1000120, 10x Genomics), 12.000 cells per sample (with a viability of more than 80%) were loaded onto the 10X genomics device (Chromium controller, 10x Genomics). The generated cDNA samples were submitted to Roche internal seq facilities for seq using the 10x Genomics' scRNA seq technology. ScRNA seq was performed using the Chromium Next GEM Single Cell 3' reagent kit v3.1 from 10X genomics according to the user guide Ref CG000315 Rev F. Targeted cell recovery of 8000 cells. Samples were indexed using Dual Index Kit TT Set A. Single Cell 3' gene expression libraries were sequenced using standard Illumina paired-end constructs beginning P5 and P7. Seq these libraries produces a standard Illumina BCL data output folder. Seq was performed using the NovaSeq6000 instrument from Illumina. Seq depth minimum of 20000 read pairs per cell, paired end dual indexing with a seq read cycles of 28-10-10-90. Libraries were quantified, normalized and pooled followed by denaturation and dilution according to the Illumina recommendations for the NovaSeq 6000 of 300 pM together with a 1% PhiX concentration.