Bleomycin-Induced Lung Injury Model

Mice underwent intraperitoneal injection with 0.018 U·g⁻¹ bleomycin (Thermo Fisher Scientific) or vehicle (PBS) twice weekly for 4 weeks (Pi et al., 2018 (link)). For diphtheria toxin studies, mice were injected intraperitoneally for three consecutive days with 100 ng of diphtheria toxin (Sigma Aldrich) before initiation of bleomycin protocol, with PBS injection used as control (Goren et al., 2009 (link)), and twice weekly thereafter. Euthanasia and data collection are performed 5 days after final injection of animal with vehicle or experimental agent (diphtheria toxin and bleomycin), Day 33 of the intraperitoneal bleomycin injection protocol. Anti‐PD‐L1 (500 μg, intraperitoneally) and rat IgG2b, both purchased from BioXcell, were administered on Day 0 and then once weekly for three additional doses (Celada et al., 2018 (link)) throughout bleomycin exposure.