GPR84 and acute respiratory distress syndrome: Similarly, in an LPS-induced acute lung injury (ALI) model, Yin et al. observed that alveolar macrophages transitioned from a CD11blo to a CD11bhi inflammatory state at later stages, whereas Gpr84−/− alveolar macrophages (AMs) reduced the mRNA expression of inflammatory cytokines such as IL-6, TNF, and IL-12β [14], ultimately leading to milder tissue damage.