miR-98 Modulates Cytokine Production from Human PBMCs in Systemic Lupus Erythematosus by Targeting IL-6 mRNA

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• Interleukin-6 (IL-6) upregulation is implicated in systemic lupus erythematosus (SLE) immunopathology.
• MicroRNA-98 (miR-98) is predicted to target the IL-6 gene's 3'-untranslated region (3'-UTR).

Purpose of the Study:

• To investigate the role of miR-98 in regulating IL-6 gene expression and cytokine production in peripheral blood mononuclear cells (PBMCs) from SLE patients.
• To assess the potential of miR-98 as a therapeutic target for SLE.

Main Methods:

• Quantitative reverse transcription PCR (qRT-PCR) to measure miR-98 and IL-6 mRNA expression in PBMCs from SLE patients and healthy controls.
• Luciferase reporter assay to confirm miR-98 targeting of IL-6.
• Cell viability assays (MTT), Western blotting, and ELISA to evaluate the effects of miR-98 modulation on PBMC proliferation and inflammatory cytokine levels (TNF-α, IL-8, IL-1β, IL-10).

Main Results:

• miR-98 expression was significantly downregulated in SLE patients' PBMCs and negatively correlated with IL-6 levels.
• miR-98 expression correlated with SLE disease activity, lupus nephritis, and anti-dsDNA antibody levels.
• IL-6 was confirmed as a direct target of miR-98. Overexpression of IL-6 promoted PBMC proliferation and inflammatory cytokine production, effects modulated by miR-98 mimics or inhibitors.
• miR-98 regulated STAT3 phosphorylation through its target gene IL-6.

Conclusions:

• miR-98 ameliorates STAT3-mediated cell proliferation and inflammatory cytokine production in SLE by targeting IL-6.
• These findings suggest that miR-98 holds potential as a therapeutic target for SLE and other IL-6-mediated diseases.