Antinephrin Autoantibodies as a Biomarker for Nephrotic Syndrome-Related Diseases

Using a hybrid technique, researchers led by Tobias B. Huber and Nicola M. Tomas identified antinephrin autoantibodies as a biomarker for monitoring the progression of kidney diseases associated with nephrotic syndrome. They presented their findings at the 61st European Renal Association Congress.

Kidney diseases associated with nephrotic syndrome include minimal change disease (MCD), primary focal segmental glomerulosclerosis (FSGS), and membranous nephropathy. Nephrotic syndrome is caused primarily by damage to podocytes, the cells that filter the kidneys, and is characterized by elevated protein levels in the urine. Diagnosing conditions associated with nephrotic syndrome is challenging. Although antinephrin autoantibodies have been observed in some patients with MCD and FSGS, their role in disease progression is unclear.

For the study, researchers used immunoprecipitation with enzyme-linked immunosorbent assay for accurate detection of antinephrin autoantibodies. They found that antinephrin autoantibodies were prevalent in 69% of adults with MCD and 90% of children with idiopathic nephrotic syndrome who had not been treated with immunosuppressive drugs. Autoantibody levels corresponded with disease activity, which suggests their potential as a biomarker for monitoring disease progression. The antibodies were rarely observed in the other diseases.

The research team further explored the effect of nephrin immunization on kidney function and disease by administering laboratory-produced nephrin protein to mice, resulting in a condition resembling MCD. Immunization resulted in the phosphorylation of nephrin and noteworthy changes in cell structure, suggesting that antibodies targeting nephrin are involved in podocyte malfunction and nephrotic syndrome.

The study’s findings could pave the way for personalized interventions for a complex set of diseases.

Source: Hengel FE, Dehde S, Lassé M, et al. Autoantibodies targeting nephrin in podocytopathies. Presented at the 61st European Renal Association Congress; May 23-26, 2024; Stockholm, Sweden.