Development of Urinary Diagnostic Biomarker for IgA Nephropathy by Lectin Microarray

Area of Science:

• Nephrology
• Glycomics
• Diagnostic Biomarkers

Background:

• Aberrantly glycosylated IgA1 is implicated in IgA nephropathy (IgAN) pathogenesis.
• The diagnostic utility of urinary glycan profiling in IgAN remains underexplored.

Purpose of the Study:

• To investigate whether urinary glycan profiling enhances the diagnostic accuracy of IgA nephropathy (IgAN).
• To evaluate the diagnostic performance of lectin microarray in urine samples for IgAN.

Main Methods:

• Retrospective study of 493 patients undergoing renal biopsy.
• Lectin microarray analysis of urine samples.
• Assessed improvement in diagnostic models by adding urinary glycan intensity to hematuria, proteinuria, and serum IgA.

Main Results:

• Three lectins (ACA, ABA, MAH) significantly improved diagnostic model performance.
• Amaranthus caudatus lectin (ACA) demonstrated robust, renal function-independent diagnostic ability.
• Adding ACA urinary glycan intensity to the reference standard showed a 3.45% net benefit.

Conclusions:

• Urinary glycan analysis, particularly with ACA, offers a useful and noninvasive strategy for IgAN diagnosis.
• Reduced levels of specific glycans (T-antigen, Sialyl T, disialyl-T) are associated with IgAN.
• The findings suggest ACA urinary glycan profiling is a robust diagnostic tool for IgAN.