cGAS Expression is Enhanced in Systemic Sclerosis Associated Interstitial Lung Disease and Stimulates Inflammatory Myofibroblast Activation.
medRxiv
; 2024 Aug 08.
Article
in En
| MEDLINE
| ID: mdl-39211872
ABSTRACT
Objective:
The lungs of patients with Systemic Sclerosis Associated Interstitial Lung Disease (SSc-ILD) contain inflammatory myofibroblasts arising in association with fibrotic stimuli and perturbed innate immunity. The innate immune DNA binding receptor Cyclic GMP-AMP synthase (cGAS) is implicated in inflammation and fibrosis, but its involvement in SSc-ILD remains unknown. We examined cGAS expression, activity, and therapeutic potential in SSc-ILD using cultured fibroblasts, precision cut lung slices (PCLS), and a well-accepted animal model.Methods:
Expression and localization of cGAS, cytokines, and type 1 interferons were evaluated in SSc-ILD lung tissues, bronchoalveolar lavage (BAL), and isolated lung fibroblasts. CGAS activation was assessed in a publicly available SSc-ILD single cell RNA sequencing dataset. Production of cytokines, type 1 interferons, and αSMA elicited by TGFß1 or local substrate stiffness were measured in normal human lung fibroblasts (NHLFs) via qRT-PCR, ELISA, and immunofluorescence. Small molecule cGAS inhibition was tested in cultured fibroblasts, human PCLS, and the bleomycin pulmonary fibrosis model.Results:
SSc-ILD lung tissue and BAL are enriched for cGAS, cytokines, and type 1 interferons. The cGAS pathway shows constitutive activation in SSc-ILD fibroblasts and is inducible in NHLFs by TGFß1 or mechanical stimuli. In these settings, and in human PCLS, cGAS expression is paralleled by the production of cytokines, type 1 interferons, and αSMA that are mitigated by a small molecule cGAS inhibitor. These findings are recapitulated in the bleomycin mouse model.Conclusion:
cGAS signaling contributes to pathogenic inflammatory myofibroblast phenotypes in SSc-ILD. Inhibiting cGAS or its downstream effectors represents a novel therapeutic approach.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
MedRxiv
Year:
2024
Document type:
Article
Country of publication:
United States