Interleukin-13 And Interleukin-18 Gene Expression Before And After The Pulse Treatment With Methylprednisolone In Primary Nephrotic Syndrome Of Children

Objectiveprimary nephrotic syndrome ( PNS) is one of the common renal disease in children, the pathogenesis of which is unclear. The purpose of the study was to evaluate the serum concentration and mRNA expression of IL - 13 and IL - 18 before and after the methylprednisolone pulse therapy ( MPT) in PNS.MethodThirty children with PNS diagnosed from October 2002 to December 2003 were enrolled in this study ( patients group). They were not treated with glu-cocorticoid and other immunosurppressives at least within the recent 3 months. The children aged from 2 to 14 years (mean 7. 5 years) and included 18 boys and 12 girls. 20 healthy children were selected as control group after physical examination. The children in control group aged from 3 to 15 years old ( mean 8years) and included 13 boys and 7 girls. All patients were treated with MPT intravenenously (15 ~30mg/Kg) for successive 3 days followed by oral predni-sone. The serum protein level of IL -13 and IL - 18 was measured by ELISA according to the manufacturers instructions. Human IL - 13 and IL - 18 ELISA kits were purchased from Jingmei Corporation Shenzhen, China. And the concentration was obtained after drawing the standard curve. The expression of IL - 13 and IL - 18 gene was detected with RT - PCR method. The important reverse transcription reagent kits were bought from TAKARA corporation Dalian and Tr-izol reagent was bought from GIBCO BRL, USA. Statistical analysis of rank sumtest was adopted for data processing.ResultsComparision of the serum IL -13 and IL - 18 levels in the same patient before and after the therapy showed significant difference( both P <0.01). The serum level in patient group before the therapy increased obviously in comparison to the level of the control group. The serum level of IL - 13 and IL - 18 in patient group after the therapy also showed significant difference compared to the control group(P <0. 01) . The mRNA expression of IL - 13 and IL - 18 in the same patient before and after therapy showed significant difference (both P <0. 01).ConclusionIL - 13 and IL - 18 maybe involved in the pathogenesis of PNS because of the significant increase of the serum IL - 13 and IL - 18 level and PBMC IL - 13 and IL - 18 mRNA expression in PNS children. Methylprednisolone pulse therapy in PNS was able to inhibit the protein production and PBMC mRNA expression of IL - 13 and IL - 18 ,so the therapeutic mechanism of MPT in PNS might be associated with the inhibition of IL - 13 and IL - 18 expression.