Regulatory T cell subsets in children with systemic lupus erythematosus

Area of Science:

• Immunology
• Pediatrics
• Rheumatology

Background:

• Systemic Lupus Erythematosus (SLE) is a complex autoimmune disease affecting children.
• Regulatory T cells (Tregs), characterized by CD4+CD25+Foxp3+ expression, play a crucial role in immune homeostasis.
• Understanding Treg dynamics in pediatric SLE is vital for disease management.

Purpose of the Study:

• To quantify CD4(+)CD25(+)Foxp3(+) T cells (Tregs) in Egyptian children diagnosed with active SLE.
• To investigate the correlation between Treg levels and disease activity scores (SLEDAI) and current drug therapies.
• To compare Treg populations in children with SLE against healthy controls.

Main Methods:

• Flow cytometry was used to enumerate CD4+CD25+, CD4+CD25(bright), CD4+CD25(dim), and Foxp3+ T cells.
• Disease activity was assessed using SLEDAI scores and anti-dsDNA antibody levels.
• 37 Egyptian children with active SLE and 20 healthy children were enrolled.

Main Results:

• Significant increases in CD4+CD25+, CD4+CD25(bright), and CD4+CD25(dim) cells were observed in SLE patients compared to controls.
• Foxp3 expression was significantly increased in CD4+CD25- and whole CD4+ T cells in SLE patients.
• No significant correlation was found between SLEDAI scores and most Treg parameters, except for a negative correlation with gated lymphocytes.
• Increased Foxp3 expression in CD4+ T cells (primarily CD25-) was noted in children with active SLE on corticosteroid therapy, independent of disease activity.

Conclusions:

• Egyptian children with active SLE exhibit altered CD4+ T cell populations, including increased Foxp3 expression, particularly on CD25- cells.
• Corticosteroid treatment in pediatric SLE may influence Foxp3 expression on CD4+ T cells.
• The study suggests a complex interplay of Treg subsets and immune regulation in pediatric SLE that warrants further investigation.