OBJECTIVETo investigate whether the local application of IL-12 gene with EBV-plasmid vector to nasal mucosa could prevent allergic inflammation in murine allergic rhinitis model.

METHODSThirty-six BALB/C mice were randomly divided into allergic rhinitis group gene therapy group and control group. In mice with OVA-induced allergic rhinitis, the EBV/lipoplex (a novel cationic lipid combined with EBV-plasmid vector, pGEG. mIL-12) was locally administered into nasal mucosa before OVA challenge. The expression of IL-12 mRNA and protein, the change of eosinophilia and mast cell, and Th2 cytokine production in the nasal mucosa were measured.

RESULTSThe amounts of IL-12 mRNA positive cells and IL-12 positive cells in nasal mucosa of gene therapy group were significantly higher than that of allergic rhinitis group (P < 0.01 and P < 0.05). The amount of eosinophils, mast cells, and the level of IL-5 expression in nasal mucosa in allergic rhinitis group were significantly higher than those in gene therapy group and control group (P < 0.01). The level of total IgE of peripheral blood in allergic rhinitis group was significantly higher than that in gene therapy group and control group (F = 1216.21, P < 0.01).

CONCLUSIONSThese findings indicated that IL-12 mRNA and protein were expressed effectively after the local administration of pGEG. mIL-12 in the nasal mucosa. The local application of pGEG. mIL-12 is effective in modulating nasal allergic response and may be a convenient method for future approach to allergic rhinitis.