CD4+ T cells in Type 1 Diabetes: Inferring Stage-specific Dysregulation from scRNA-seq.

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• Type 1 diabetes (T1D) pathogenesis requires detailed understanding of immune cell dynamics.
• Previous studies lack high-resolution, stage-specific immune profiling in T1D.

Purpose of the Study:

• To perform a comprehensive single-cell transcriptomic analysis of immune cells in children with T1D, relatives, and controls.
• To identify distinct immune signatures and regulatory networks across T1D disease stages.

Main Methods:

• Large-scale single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs).
• Analysis of immune cell subsets including regulatory T cells (Tregs), Th22, MAIT, and Th17 cells.
• Transcriptional regulatory network analysis and intercellular signaling pathway investigation.

Main Results:

• New-onset T1D shows expanded non-mature Tregs.
• Active autoimmunity features increased Th22 cells, decreased MAIT cells, and elevated ADAM10/ADAM17 expression.
• Later T1D stages exhibit Th17 cell accumulation and altered TGF-β1/IL-12 signaling.
• BACH2 identified as a key regulator of Treg maturation.

Conclusions:

• Dynamic shifts in CD4+ T cell subsets and cell-cell communication map T1D immunological trajectories.
• Dysregulation of BACH2 may contribute to immune tolerance breakdown in T1D.
• Findings reveal potential stage-specific biomarkers and therapeutic targets for T1D intervention.