STING-associated lung disease in mice relies on T cells but not type I interferon.

BACKGROUND

Monogenic interferonopathies are thought to be mediated by type I interferon. For example, a gain-of-function mutation in stimulator of interferon genes (STING; N153S) upregulates type I interferon-stimulated genes and causes perivascular inflammatory lung disease in mice. The equivalent mutation in human subjects also causes lung disease, which is thought to require signaling through the cyclic GMP-AMP synthase (cGAS)-STING pathway and subsequent activation of interferon regulatory factors (IRFs) 3 and 7, type I interferon, and interferon-stimulated genes.

OBJECTIVE

We set out to define the roles of cGAS, IRF3, IRF7, the type I interferon receptor (IFN-α and IFN-β receptor subunit 1 [IFNAR1]), T cells, and B cells in spontaneous lung disease in STING N153S mice.

METHODS

STING N153S mice were crossed to animals lacking cGAS, IRF3/IRF7, IFNAR1, adaptive immunity, αβ T cells, and mature B cells. Mice were evaluated for spontaneous lung disease. Additionally, bone marrow chimeric mice were assessed for lung disease severity and survival.

RESULTS

Lung disease in STING N153S mice developed independently of cGAS, IRF3/IRF7, and IFNAR1. Bone marrow transplantation revealed that certain features of STING N153S-associated disease are intrinsic to the hematopoietic compartment. Recombination-activating gene 1 (Rag1) STING N153S mice that lack adaptive immunity had no lung disease, and T-cell receptor β chain (Tcrb) STING N153S animals only had mild disease. STING N153S led to a reduction in percentages and numbers of naive and regulatory T cells, as well as an increased frequency of cytokine-producing effector T cells.

CONCLUSION

Spontaneous lung disease in STING N153S mice develops independently of type I interferon signaling and cGAS. STING N153S relies primarily on T cells to promote lung disease in mice.