Back
For best output, select "Paper Size" as "A4" and "Margin" as "0" or "None".
To save or print to PDF, please select Print Destination > Save as PDF, enable Background Graphics under "More Settings", then click "Save".
During the congress, E-Posters will be accessible to all participants on the congress website 24/7, as well as in the E-poster stations in the congress center.
Preparing your E-Poster
Please review the E-Poster format requirements carefully when preparing your E-Poster. Should your E-Poster not meet the mentioned requirements, it may not be displayed as described above.
E-Poster Submission Deadline
Please prepare and upload your E-Poster no later than March 14, 2026 11.59PM CET. After this date, you will no longer be able to prepare and upload your E-poster and it will not be displayed and accessible on the congress website.
Please follow the instructions below to input your abstract title.
Abstract titles should be brief and reflect the content of the abstract.
Anti-nephrin autoantibodies have been recently reported to be one of the etiologies of nephrotic syndrome (NS), suggesting their potential utility as biomarkers for NS. Although several studies have measured anti-nephrin autoantibodies and reported their prevalence in NS patients, the reported levels are inconsistent across studies. This inconsistency may be attributed to differences in assay sensitivity and the type of antigen used for immunocapture, the latter being affected by source cell type and domain construct used. To address these issues, we aimed to develop an automated immunoassay for measuring anti-nephrin autoantibodies, utilizing an antigen capable of capturing such antibodies with a high sensitivity.
The antigen used for immunocapture of anti-nephrin autoantibodies was the extracellular domain of nephrin recombinantly expressed and purified from human cell lines. The three free cysteine residues in this domain were mutated to improve assay sensitivity. An automated immunoassay was developed for the Automated Immunoassay System HISCL-5000 (Pre-market Notification Number: 28B1X10014000011, Marketing Authorization Holder: Sysmex Corporation) by using the mutated antigen for immunocapture, ALP-fused anti-human IgG antibody and chemiluminescence for detection. Clinical samples (serum or plasma) were diluted and filtered prior to the assay. Intra-assay and inter-assay imprecision, reagent storage stability, and the impact of major blood interferents (hemoglobin, lipids, conjugated and free bilirubin, rheumatoid factor) were evaluated. For evaluating clinical performance, autoantibody levels in samples obtained from pediatric NS cases at the time of initial onset and remission (n=32), and pediatric disease controls (n=30) were measured and compared.
The mutant antigen demonstrated higher reactivity in multiple samples compared to the wild-type, with the effect being most pronounced for cysteine to valine substitutions. The assay developed using this antigen exhibited high reproducibility (intra-assay imprecision CV <2%, inter-assay imprecision CV <6%) and maintained good storage stability (bias <5%) for one month, showing minimal impact from all evaluated blood interferents. In the paired analysis of 32 pediatric NS cases during active and remission phases, the antibody levels during remission were significantly lower than those during the active phase (p < 10^-6). Furthermore, setting a cutoff based on autoantibody levels in pediatric disease controls, 29/32 (90.6%) active phase cases were found to be autoantibody positive. This was reduced to 3/32 (9.4%) for cases in remission and 1/30 (3.3%) for pediatric disease controls.
Using a novel mutant nephrin antigen, we established a highly sensitive anti-nephrin autoantibody immunoassay that excels in reproducibility and stability, and sensitively reflects disease progression. This assay could serve as a powerful tool for evaluating the clinical significance of anti-nephrin autoantibodies as biomarkers for NS. Moreover, the developed reagents are potentially applicable to fully automated immunoassay systems, paving the way for improved testing of NS in medical institutions and clinical laboratories.
