Urinary T cells may be useful in identifying antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and in establishing a prognosis, according to findings from a proof of concept study.
A team led by Adrian Schreiber, MD, of Charité-Universitätsmedizin in Berlin, Germany, used flow cytometry to quantify T cell subsets in blood and urine specimens from 95 patients with ANCA-associated vasculitis and 8 healthy patients serving as a control arm.
Patients with active renal ANCA-associated vasculitis had significantly higher urinary T cell counts compared with patients in remission, those with extrarenal manifestations, and the control arm, the investigators reported in Kidney International Reports.
Urinary T cells demonstrated robust discrimination of disease activity with superior performance compared with monocyte chemoattractant protein-1 (MCP-1) and soluble CD163 (sCD163), which have shown promise as urinary biomarkers of renal disease in ANCA-associated vasculitis, according to the investigators. Patients with kidney biopsies classified as “crescentic” according to Berden classification showed higher urinary T cell counts. Further, patterns of urinary regulatory T cells and T helper cells were associated with clinical response and risk for renal relapse.
“In summary,” the authors wrote, “urinary T cells directly reflect the renal inflammatory milieu and show reliable biomarker characteristics, outperforming soluble markers.”
If confirmed by future studies, urinary T cells would represent the first noninvasive biomarker to assess disease activity, enable prognosis of clinical response, and identify patients who could benefit from tailored treatment strategies, Dr Schreiber and colleagues concluded.
“These characteristics could make urinary T cells a perfect tool for a personalized treatment of ANCA-associated glomerulonephritis,” they added.
Sonnemann J, Klocke J, Bieringer M, et al. Urinary T cells identify renal antineutrophil cytoplasmic antibody-associated vasculitis and predict prognosis: A proof of concept study. Kidney Int Rep. Published online January 17, 2023. doi:10.1016/j.ekir.2023.01.013