Urinary T Cells in Active Lupus Nephritis Reveal Effector Memory Phenotype

Strategic Insights -

Researchers at the University Medical Center in Netherlands have uncovered new data on systemic lupus erythematosus (SLE), highlighting alterations in T cell homeostasis and an increased effector response, which contribute to tissue injury. In a study published in Annals of the Rheumatic Diseases, the team investigated the distribution and phenotype of effector memory T cells in the peripheral blood and their presence in renal biopsies and urine of patients with SLE. The findings indicate that migrated effector memory T cells (CD45RO(+)CCR7?) play a significant role in tissue injury, and these cells could serve as an additional marker of renal activity in patients with SLE.

Key Takeaways:

  • The study enrolled 43 patients with SLE and 20 healthy controls to investigate the distribution and phenotype of effector memory T cells.
  • CD4(+) T(EM) cells and CD8(+) T(EM) cells were analyzed in peripheral blood and urine using flow cytometric analysis.
  • In patients with active lupus nephritis, the percentage of circulating CD8(+) T(EM) cells was significantly decreased compared to healthy controls.
  • Analysis of urinary sediment in active renal disease showed increased numbers of CD4(+) T cells (134[+ or -]71 cells/ml) and CD8(+) T cells (287[+ or -]220 cells/ml).
  • 73.6[+ or -]8.3% of urinary CD4(+) T cells and 69.3[+ or -]26.0% of urinary CD8(+) T cells expressed the T(EM) phenotype.
  • CD8(+) cells were also found in renal biopsies, supporting the hypothesis that CD8(+) effector memory cells migrate from the PB to the kidney and appear in the urine during active renal disease in patients with SLE.

Statistics:

  • 43 patients with SLE were enrolled in the study.
  • 20 healthy controls were included in the study.
  • CD4(+) T(EM) cells were analyzed in PB and urine.
  • CD8(+) T(EM) cells were analyzed in PB and urine.
  • In patients with active lupus nephritis, the percentage of circulating CD8(+) T(EM) cells was 30.4[+ or -]15.9% (p=0.01).
  • Increased numbers of CD4(+) T cells (134[+ or -]71 cells/ml) and CD8(+) T cells (287[+ or -]220 cells/ml) were found in urinary sediment in active renal disease.
  • 73.6[+ or -]8.3% of urinary CD4(+) T cells expressed the T(EM) phenotype.
  • 69.3[+ or -]26.0% of urinary CD8(+) T cells expressed the T(EM) phenotype.

Sources:

  • S. Dolff and colleagues, University Medical Center. (Urinary T cells in active lupus nephritis show an effector memory phenotype. Annals of the Rheumatic Diseases, 2010;69(11):2034-41)