Abstract: Objective To investigate the effects of polysaccharide nucleic acid fraction of Bacillus Calmette Guerin(BCG-PSN)on the expression of NF-κB and Thl/Th2 cytokines(IL-4, IgE, IFN-γ,IL-12)in PBMC of patients with atopic dermatitis(AD). Methods Peripheral blood mononuclear cells(PBMC)isolated from AD patients(n=30)and healthy control individuals(n=10)were stimulated with PHA for 1 d, followed by culture with or without BCG-PSN. PBMC were harvested after 1.5 h of cullure with or without BCG-PSN, and NF-κB activation was analyzed with a trans-AM NF-κB p65 transcription factor assay kit. Cell culture supernatants were harvested 72 h after culture initiation and analyzed by double antibody sandwich ELISA for IL-4, IgE, IFN-γ, and IL-12. Results After treatment of BCG-PSN, the NF-κB activation and expression of IgE in PBMC of AD patients were significantly reduced(P=0.003,P=0.009, respectively),whereas the expression of IFN-γ and IL-12 was significantly increased(P=0.000).Meanwhile, there was no significant change in the expression of IL-4 before and after treatment(P>0.05).Furthermore, there were significant inverse correlations between the change in NF-κB activation and changes in the expression of IFN-γ and IL-12(p<0.05),whereas no significant correlations were identified between the change in NF-κB activation and changes in the expression of IL-4 and IgE(P>0.05). Conclusion These results indicate that one of the therapeutic mechanisms of BCG-PSN on atopic dermatitis may be upregulating the expression of IFN-γ and IL-12 in PBMC by inhibiting the NF-κB activation.

Key words: Dermatitis, atopic;Bacillus Calmette Guerin, polysaccharide nucleic acid fraction, NF-kappa B, Interleukin-4, Interleukin-12, Interferon type II, Immunoglobulin E