The Role Of P-Selectin In The Pathogenesis Of Henoch-Schonlein Purpura In Children

Objective:To investigate the association between P-selectin gene polymorphisms and soluble P-selectin levels and their relation to Henoch-Schonlein purpura(HSP) and renal involvement (HSPN) of children.Methods(1) All patients were divided into HSPN and non-HSPN groups by urinary routine.Serum P-selectin was detected in 56 children with HSP in different phases and 35 normal children by ABC-ELISA.Urnary microamount albumin were also examined.Positive rate of Hp-IgG between normal children and children with HSP were compared.(2) A case-control study conducted between Eighty-six patients with HSP(including 40 with HSPN)and 70 healthy ethnically matched controls.P-selectin promoter -825 and -2123 polymorphisms were typed by Polymerase Chain Reaction(PCR)- direct sequencing and Polymerase Chain Reaction-Restriction Fragment Length Polymorphism(PCR-RFLP).Results(1) The levels of serum P-selectin in children with HSPN[(322.78±27.94) ug/L]were significantly higher than those in normal[(238.88±44.3) ug/L]and non-HSPN children[(282.31±32.44) ug/L](P<0.01).P-selectin promoter -825,-2123 polymorphism were found widely in above children.(2) Compared with the healthy controls,the frequencies of AA genotype were significantly higher in the HSPN and non-HSPN patients(P<0.05).The frequencies of AA genotype and A allele were significantly higher in the HSPN than those in the non-HSPN(P< 0.05).Compared with the healthy controls,the frequencies of GG genotype and G allele of P-selectin promoter -2123 were significantly higher in the non-HSPN patients,but the frequencies of CG genotype and CC genotype were not significantly different between patients and controls. There were no significant differences of P-selectin promoter -2123 genotype and allele frequencies between HSPN patients and nHSPN patients.P-selectin -825,-2123 polymorphisms were strongly associated with soluble P-selectin level(P<0.001).The expression level of serum P-selectin were greatly decreased in case of acute phase than those of recovery phase(P<0.01). Serum P-selectin level positively related to urnary microalbumin(r=0.622,P<0.01);Hp infection rate in patients and normal were 48%and 29%. Conclusions Soluble P-selectin levels and P-selectin promoter -825,-2123 polymorphisms appear to be associated with HSP and HSPN.P-selectin promoter -825,-2123 polymorphisms were strongly associated with soluble P-selectin level,thus suggesting the genetic effect of P-selectin gene in the pathogenesis of HSP and HSPN.Hp infection is related with HSP.