TREM-1 Contributes to Inflammation in IgA Nephropathy

Area of Science:

• Nephrology
• Immunology
• Inflammation Research

Background:

• Circulating IgA1 immune complexes (cIgA1) are implicated in IgA nephropathy (IgAN) pathogenesis.
• cIgA1 can trigger inflammatory factors like MCP-1 and IL-6, contributing to kidney injury.
• Soluble TREM-1 (sTREM-1) was previously identified as upregulated by mesangial cells under cIgA1 challenge.

Purpose of the Study:

• To investigate the role of TREM-1 in cIgA1-induced kidney injury in IgAN.
• To explore the relationship between TREM-1, inflammation, and disease severity in IgAN patients.

Main Methods:

• Enrolled 35 IgAN patients and 17 healthy controls.
• Isolated cIgA1 and treated cultured mesangial cells.
• Measured TREM-1 mRNA, sTREM-1, MCP-1, and IL-6 levels in cell supernatant and urine.

Main Results:

• cIgA1 significantly upregulated TREM-1 expression in mesangial cells.
• sTREM-1 levels correlated positively with MCP-1 in mesangial cell supernatant.
• Higher urinary sTREM-1 levels were found in IgAN patients and associated with severe clinical and pathological manifestations.

Conclusions:

• TREM-1 plays a role in cIgA1-induced inflammatory kidney injury in IgAN.
• Urinary sTREM-1 may serve as a biomarker for disease severity in IgAN.