A pilot prospective cohort study: Changes in circulating T-lymphocyte subsets during steroid therapy in patients with nephrotic syndrome

Objective Glucocorticoids are used to treat nephrotic syndrome; however, some patients develop resistance. T-lymphocyte subsets are involved in immune regulation and may be associated with disease progression and treatment response. The current prospective pilot cohort study explored T-cell immune phenotypes associated with steroid responsiveness in patients with nephrotic syndrome. Methods Eleven patients newly diagnosed with nephrotic syndrome between 2023 and 2024, classified as steroid-sensitive or steroid-resistant based on treatment outcomes, and 14 healthy volunteers were enrolled. Peripheral blood samples were collected at diagnosis (baseline), at weeks 4 and 8 after hormone therapy, and during monthly follow-up visits. T-cell subsets and T-cell immunoglobulin and mucin domain–containing protein 3 (TIM-3) expression were analyzed using flow cytometry. Differences were identified by performing variance analysis, and correlations were assessed by performing linear regression. Results CD3 + CD8 + T cells differed between steroid-resistant patients and both steroid-responsive patients and controls ( p < 0.05). The proportion of CD3 + TIM-3 + T cells differed between controls and steroid-sensitive patients ( p < 0.001). Steroid treatment was associated with an increase in CD3 + TIM-3 + T cells and a potential negative correlation with albumin levels in steroid-sensitive patients. Conclusions T-cell immune phenotypes, particularly TIM-3-expressing T cells, may be associated with steroid responsiveness in nephrotic syndrome. The current findings provide preliminary evidence for potential laboratory markers related to immune regulation.