RGS2 is an innate immune checkpoint for suppressing Gαq mediated IFNγ generation and lung injury

Infections can trigger the release of IFNγ, a type II interferon, which exacerbates tissue inflammation and may lead to severe acute lung injury (ALI). However, the regulatory mechanisms of IFNγ production in the lungs are not fully understood. In this study, we identified RGS2 as a crucial regulator of IFNγ levels in the lungs during infection. The absence of RGS2 led to persistently elevated IFNγ production in macrophages, resulting in unresolved inflammatory lung damage. Notably, this effect was absent in RGS2-deficient chimeric mice that received wild-type bone marrow or RGS2 expression in alveolar macrophages (AMs), as well as in those treated with an IFNγ-blocking antibody. RGS2 exerts its regulatory role by inhibiting Gαq-mediated IFNγ production and inflammatory signaling in AMs. Consequently, the inhibition of Gαq in RGS2-deficient mice prevented IFNγ production in AMs and shifted their transcriptomic profile from an inflammatory to a reparative state. These findings suggest that the RGS2-Gαq signaling pathway could be a promising therapeutic target for mitigating inflammatory lung injury.