Regulatory T Cells in Systemic Sclerosis: a Comprehensive Review

Area of Science:

• Immunology
• Rheumatology
• Cell Biology

Background:

• Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by vascular damage, immune dysregulation, and fibrosis.
• Regulatory T cells (Tregs) are crucial for maintaining immune homeostasis and preventing autoimmunity.
• The precise role of Tregs in SSc pathogenesis remains incompletely understood.

Purpose of the Study:

• To review and synthesize current knowledge on the role of Tregs in systemic sclerosis.
• To explore the functional capacity and numbers of Tregs in SSc patients.
• To discuss the potential transformation of Tregs into pathogenic effector cells in SSc.

Main Methods:

• Literature review and synthesis of existing studies on Tregs in SSc.
• Analysis of data regarding Treg numbers, function, and distribution in SSc.
• Examination of the impact of disease stage and activity on Treg populations.

Main Results:

• Circulating Tregs in SSc often exhibit decreased functional capacity.
• Treg numbers can be increased in active SSc but depleted in long-standing disease.
• Skin-resident Tregs are diminished in advanced SSc but may be active in early stages.
• Tregs can transform into pro-inflammatory (Th17) or pro-fibrotic (Th2) cells in SSc.

Conclusions:

• Tregs have a multifaceted role in SSc, with impaired function being a key feature.
• Treg dysfunction and transformation contribute to the immune dysregulation and fibrosis seen in SSc.
• Further research is needed to clarify the effects of SSc treatments on Treg function.