Proportion of circulating T follicular helper cells in peripheral blood of systemic lupus erythematosus patients: A systematic review and meta-analysis

Dysregulation of circulating follicular helper T (cTfh) cells plays a key role in the breakdown of immune tolerance and the pathogenesis of antibody-mediated autoimmune diseases, including systemic lupus erythematosus (SLE). This study aims to evaluate the proportions of cTfh cells and their potential pathogenic mechanisms in the peripheral blood of SLE patients through a systematic review and meta-analysis. Systematic search and review were conducted across PubMed, Cochrane Library, EMBASE, and Web of Science to identify relevant studies. A meta-analysis was performed to compare the proportions of cTfh cells and their subsets between SLE patients and healthy controls (HC). Subgroup analyses were conducted based on the markers used for defining cTfh cells and geographical regions. The meta-analysis revealed a significantly higher proportion of cTfh cells in SLE patients compared to HC (SMD 0.904, [0.620, 1.188], p < 0.01). Subgroup analyses showed a consistent increase in cTfh cells in SLE across different markers. Geographically, both Asian (SMD 1.005, [0.608, 1.402], p < 0.01) and non-Asian populations (SMD 0.708, [0.428, 0.988], p < 0.01) demonstrated elevated cTfh cell proportions in SLE. A trend toward a decrease in Tfh1 cells and an increase in Tfh17 cells was observed, though neither reached statistical significance. Our study demonstrates that cTfh cells proportions are significantly elevated in SLE patients, supporting their role in the pathogenesis of SLE. These findings suggest that cTfh cells could serve as potential biomarkers for SLE and therapeutic targets for treatment.