Serum Levels of B-Cell Activating Factor and A Proliferation-Inducing Ligand in Children with Steroid-Sensitive...

The therapeutic efficacy of B-cell-depleting anti-CD20 treatments is well established for children with steroid-sensitive nephrotic syndrome (SSNS), thus suggesting that B cells may play an important role in the occurrence of this disease. However, the role of B-cell survival factors and cytokines in SSNS has yet to be fully elucidated.

We used commercially available ELISA kits to determine the serum levels of B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) in 84 children with SSNS and 25 healthy controls. Then, we performed correlation analysis between these two serum factors and clinical parameters in children with SSNS.

The serum level of BAFF in the relapse group was 1,295.2 ± 584.2 pg/mL, significantly higher than other groups (p < 0.001). The serum level of APRIL in the relapse group was 2,830.5 ± 945.8 pg/mL, significantly higher than the other groups (p < 0.001). The proportion (%) of memory B cells was positively correlated with the levels of BAFF and APRIL in children with SSNS (Pearson's correlation coefficient: r = 0.351, p = 0.001; Pearson's r = 0.234, p = 0.032). The proportion (%) of transitional B cells was negatively correlated with the levels of BAFF (Pearson's r = -0.237, p = 0.030) while the serum levels of IgG were negatively correlated with those of APRIL (Pearson's r = -0.274, p = 0.012).

Our data indicate that BAFF appears to play a role in the recurrence of SSNS while APRIL appears to play a role in the pathogenesis of this condition, thus indicating that these molecules represent potential therapeutic targets for SSNS.