Immunoglobulin A Nephropathy: Molecular Pathogenesis and Targeted Therapy

Area of Science:

• Nephrology
• Immunology
• Molecular Biology

Background:

• Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide, characterized by mesangial IgA deposition and varied clinical outcomes.
• Current treatments, including renin-angiotensin system inhibitors and empirical immunosuppression, often fail to prevent high lifetime kidney failure rates.
• The traditional multi-hit hypothesis inadequately explains the chronic, self-amplifying nature of IgAN.

Purpose of the Study:

• To review advances in IgAN molecular pathogenesis and introduce the "spiral hypothesis" as a dynamic disease model.
• To discuss emerging targeted therapies and evaluate treat-to-target frameworks for personalized management.
• To outline future priorities for optimizing IgAN treatment protocols and safety monitoring.

Main Methods:

• Synthesis of current literature on IgAN molecular pathogenesis.
• Critical evaluation of emerging targeted therapies, including B-cell agents, complement inhibitors, and mucosal immunomodulators.
• Analysis of treat-to-target frameworks and biomarker-guided personalization strategies.

Main Results:

• The "spiral hypothesis" offers a dynamic model of cyclical immune-injury cascades, better explaining IgAN chronicity and the need for sustained therapy.
• Emerging therapies target upstream immunological drivers and downstream fibrotic pathways, enabling earlier and more precise interventions.
• Defined remission endpoints (e.g., proteinuria <0.3 g/day) and biomarker-guided personalization are key to proactive management.

Conclusions:

• A paradigm shift towards proactive, individualized management of IgAN is necessary, prioritizing sequential use of novel agents based on risk stratification.
• The "spiral hypothesis" necessitates sustained maintenance therapy, moving beyond historical treatment paradigms.
• Future research should focus on optimizing treatment for high-risk IgAN phenotypes and ensuring long-term therapeutic safety and efficacy.