Mean BUN and serum creatinine in Rag2–/– mice 13 days after they received 1 × 108, 5 × 107, or 1 × 107 anti-MPO splenocytes, anti-BSA splenocytes, or nonimmunized control splenocytes. The normal mouse assay reference range was 18–29 mg/dl for BUN and 0.2–0.8 mg/dl for serum creatinine. Samples taken before injection of splenocytes were within the reference ranges (data not shown).