Effects of fludarabine treatment on murine lupus nephritis.

BXSB mice, a murine model of systemic lupus erythematosus (SLE), were treated with two different doses of fludarabine for a four-week period and examined two weeks after the final dose. Control mice were treated with saline or cyclophosphamide. Mice treated with fludarabine had a significant reduction in renal pathology compared to control mice. Fludarabine-treated mice also had an almost 10-fold increase in percentile of CD8+CD25+ T cells in the spleen and a smaller but significant increase in CD4+CD25+ cells. Mice treated with cyclophosphamide had a greater leucopenia compared to the other groups and a significant reduction in percentile of B220+ cells in peripheral blood and spleen. Serum autoantibody levels to dsDNA did not differ significantly among the groups, but were higher in 4/10 mice treated with fludarabine. Although few trials of fludarabine for human SLE have been conducted, additional studies may be warranted.