Single cell analysis identified IFN signaling activation contributes to the pathogenesis of pediatric steroid-sensitive nephrotic syndrome.

Abstract

Background: Idiopathic nephrotic syndrome (INS) is a prevalent condition whose recurrence leads to multiple adverse effects. Previous studies on INS pathogenesis primarily focused on immune dysregulation, particularly T-cell changes and their correlation with cytokine shifts. Accumulating evidence suggests that B-cell dysfunction also plays a role. Nevertheless, a comprehensive understanding of the mechanisms and effective treatment strategies remains incomplete.

Methods: This study investigates changes in gene expressions and cellular interactions of immune cells at a single-cell level using peripheral blood mononuclear cells (PBMCs). And subsequently validated through quantitative PCR (qPCR), enzyme-linked immunosorbent assay (ELISA), and flow cytometry.

Results: We identified seven main clusters using unsupervised clustering of 103,213 high-quality single cells. Through unsupervised clustering, patient-specific T cells (IFI44L + CD4 + T cells) that exhibited a pronounced elevation of interferon-stimulated genes (ISGs) is identified. Activation of ISGs and interferon (IFN)-related pathways are also observed in other clusters. Specifically, this study demonstrates that interferon-γ (IFN-γ) plays a crucial role by promoting the interaction between B-cell activating factor (BAFF) and receptors on B cells. This interaction triggers the release of autoantibodies, thereby initiating INS pathogenesis. Furthermore, telitacicept has shown efficacy in treating pediatric patients with frequent relapse NS(FRNS).

Conclusions: Overall, our findings underscore the role of interferon and its related pathways in INS pathogenesis, providing novel therapeutic interventions for NS.