Potential diagnostic biomarkers for IgA nephropathy: a comparative study pre- and post-tonsillectomy

Area of Science:

• Biochemistry
• Immunology
• Nephrology

Background:

• Biomarkers such as BAFF, ST6GALNAC2, C1GALT1, and COSMC in peripheral blood mononuclear cells (PBMCs) and plasma levels of IgA1 and galactose-deficient IgA1 (Gd-IgA1) are potential indicators for IgA nephropathy (IgAN).
• Understanding the impact of therapeutic interventions like tonsillectomy on these biomarkers is crucial for managing IgAN.

Purpose of the Study:

• To comparatively analyze the changes in specific protein biomarkers (BAFF, ST6GALNAC2, C1GALT1, COSMC) and plasma IgA1/Gd-IgA1 levels in IgAN patients before and after tonsillectomy.
• To investigate the effect of tonsillectomy on these potential IgAN biomarkers in non-IgAN patients and healthy controls.

Main Methods:

• Real-time PCR was used to quantify mRNA levels of BAFF, ST6GALNAC2, C1GALT1, and COSMC in PBMCs from 16 IgAN patients, 3 non-IgAN patients, and 16 healthy controls.
• Plasma IgA1 and Gd-IgA1 levels were measured using ELISA and VV lectin-ELISA, respectively, in samples collected pre- and post-tonsillectomy.

Main Results:

• Before tonsillectomy, IgAN patients exhibited significantly higher levels of BAFF, ST6GALNAC2, C1GALT1, COSMC mRNA, and plasma IgA1/Gd-IgA1 compared to healthy controls.
• Tonsillectomy led to increased BAFF and ST6GALNAC2 expression and plasma IgA1, while decreasing C1GALT1 and COSMC expression in IgAN patients.
• No significant changes in these biomarkers were observed in non-IgAN patients post-tonsillectomy. Positive correlations were found between BAFF/IgA1 and ST6GALNAC2/Gd-IgA1.

Conclusions:

• Tonsillectomy significantly alters the expression of BAFF, ST6GALNAC2, C1GALT1, and COSMC in PBMCs and plasma IgA1 levels in IgAN patients.
• BAFF and ST6GALNAC2 show potential roles in regulating IgA1 secretion and O-glycosylation, suggesting their involvement in IgAN pathogenesis.