RGC32 Promotes Bleomycin-Induced Systemic Sclerosis in a Murine Disease Model by Modulating Classically Activated...

Area of Science:

• Immunology
• Rheumatology
• Cell Biology

Background:

• Systemic sclerosis (SSc) is an autoimmune disease involving inflammation and fibrosis.
• The precise mechanisms of inflammation-driven SSc pathogenesis remain unclear.
• Inflammatory cells and cytokines are implicated in SSc development.

Purpose of the Study:

• To investigate the role of response gene to complement 32 (RGC32) in the early stages of SSc.
• To determine if RGC32 influences the inflammatory response in SSc.
• To explore RGC32 as a potential therapeutic target for SSc.

Main Methods:

• Studied RGC32 expression in macrophages during bleomycin-induced SSc in mice.
• Utilized RGC32-deficient mice to assess its role in SSc pathogenesis.
• Analyzed the impact of RGC32 on M1 macrophage polarization and inflammatory mediator production (iNOS, IL-1β).
• Investigated the interaction of RGC32 with NF-κB proteins.

Main Results:

• RGC32 is highly expressed in macrophages during early SSc.
• RGC32 deficiency significantly reduced skin and lung sclerosis in mice.
• RGC32 is crucial for inducible NO synthase (iNOS) and IL-1β expression in M1 macrophages.
• RGC32 interacts with NF-κB to promote inflammatory gene expression.

Conclusions:

• RGC32 promotes SSc onset by regulating M1 macrophage inflammatory responses.
• RGC32 is a novel regulator of classically activated macrophage (M1) differentiation.
• Targeting RGC32 may offer a new therapeutic strategy for treating systemic sclerosis.