Curative effect of BCG-polysaccharide nuceic acid on atopic dermatitis in mice

Objective:To explore the effect of bacilli Galmette-Gurin(BCG)-polysaccharide nuceic acid on atopic dermatitis in mice and its mechanism.Methods:Forty NC/Nga mice were selected and randomly divided into Group A(model group),Group B(dexamethasone treatment group),Group C(BCG polysaccharide nucleic acid treatment group) and Group D(control group) with 10 mice in each group.Atopic dermatitis model were constructed by applying 2,4-dinitrochlorobenzene on the skin of the mice.Mice in Group D were treated with acetone solution(100 μ L) on the foot pad and abdomen after hair removal at the age of 7 weeks.then on ear skin at the age of 8-13 weeks.For mice in A,B and C groups,100 μL of acetone solution containing 2,4-dinitrochlorobenzene was applied to the foot pad and the abdomen at the age of 7 weeks,then on ear skins at the age of8 to 13 weeks.At the age of 7-13 weeks,mice in Group A and Group D were treated with 100 μL saline(i.p.);mice were given dexamethasone(0.1 mL/kg,i.p.) every other day for 7 weeks in Group B;mice were treated with BCG polysaccharide nucleic acid(0.5 mg/kg,i.p.) every other day for7 weeks in Group C.The ear thickness was measured every week and the scratching frequency was recorded 1 times for 10 min a week.The mice were sacrificed after the last administration of drugs,IgE,IL-4,IL-10,IL-I2 and IFN- γ in the plasma were detected using ELISA,and RT-PCR method was employed to detect the concentrations of IL-4,IL-10,IL-12 and IFN- γ proteins.After IIK staining,the lesion degree of inflammation in ear tissue was observed microscopically.Results:The ear thickness and scratching frequency of Group A were significantly higher than those in group B,C and D(P 0.05);the concentrations of IgE,IL-4 and IL-10 in the plasma and the expression of IL-4,IL-10 mRNA in the spleen tissues of Group A,B and C were all significantly higher than those of Group D(P<0.05);the concentrations of plasma IL-12 and IFN- γ,and spleen protein