Abstract: TH-PO0682
Reactive Oxygen Species Generation in Neutrophils After Stimulation with Lupus Nephritis Serum
Session Information
- Glomerular Diseases: Immunopathogenesis and Targeted Therapeutics
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology
Authors
- Lightman, Rebecca, MaineHealth, Portland, Maine, United States
- Shoctor, Nicholas A., University of Louisville School of Medicine, Louisville, Kentucky, United States
- Tandon, Shweta, University of Louisville School of Medicine, Louisville, Kentucky, United States
- Brady, Makayla, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States
- Daniels, Michael W., University of Louisville School of Medicine, Louisville, Kentucky, United States
- Caster, Dawn J., University of Louisville School of Medicine, Louisville, Kentucky, United States
- Powell, David W., University of Louisville School of Medicine, Louisville, Kentucky, United States
Background
Systemic lupus erythematosus is a multi-system autoimmune disease which commonly manifests in the kidney as lupus nephritis (LN). Neutrophils are increasingly implicated in LN pathogenesis. Prior work in our lab suggests LN serum contains endogenous neutrophil activators, which may vary based on LN disease status. We investigated if healthy donor (HD) neutrophils create reactive oxygen species (ROS) after stimulation with both pooled and individual LN serum, and if responses differ by LN disease status.
Methods
Neutrophils were isolated from whole blood of HDs. Active LN was defined as a urine protein-to-creatinine ratio >500.
In 10 pooled serum experiments, neutrophil treatment groups included 10% pooled serum from active LN, inactive LN, or HDs. Each serum pool consisted of equal volumes from 10 patients. For LN conditions, the pools were patient-matched: active and inactive samples came from the same 10 patients at different time points.
In 5 un-pooled experiments, HD neutrophils were stimulated with serum from the individual patients included in the pools, again using paired active and inactive samples.
ROS generation was measured by spectrophotometry using cytochrome C reduction as an indicator.
Results
In the pooled experiments, inactive serum caused greater ROS production than active LN or HD serum (p=0.015, p=0.018; Friedman test with Bonferroni-corrected Wilcoxon tests).
In un-pooled experiments, inactive serum from 3 LN patients induced more ROS compared to active (p<0.0001), while serum from 3 other patients showed the opposite pattern (p=0.0137,0.0002,0.0016). The 4 remaining LN patients showed no significant difference (two-way ANOVA with Šídák’s test).
Conclusion
Pooled analyses suggest inactive LN serum causes the greatest neutrophil response, yet un-pooling the samples reveals inter-patient variability in serum profile’s ability to stimulate neutrophils. While only 3 individual patients’ serum resulted in greater ROS generation from inactive LN serum, the pooled serum yielded results much like these 3 samples; this suggests the presence of one or more strong but currently unidentified neutrophil activators in these inactive samples. Our findings provide further insight for neutrophil activity in LN and suggest that this assay may provide another diagnostic measurement for LN activity.
Funding
- NIDDK Support