OBJECTIVETo evaluate the effect of intranasal liposome-mediated IL-12 gene therapy on the eosinophils and IL-5 in the murine model of allergic rhinitis.

METHODSThirty-six BALB/C mice were randomly divided into allergic rhinitis (AR) group, gene therapy group and control group. Allergic rhinitis group were sensitized and stimulated by ovalbumin (OVA), and gene therapy group were administered with liposome-mediated pGEG. mIL-12 transnasally before stimulated. The eosinophils in bone marrow were counted by Wright's staining, and the eosinophils in nasal mucosa were counted by HE staining. The eosinophils of peripheral blood were detected by flow cytometry. The expression of IL-5 in bone marrow and nasal mucosa was examined by immunohistochemistry. The IL-5 in serum was detected by ELISA.

RESULTSAmong the three groups, the difference of all data was statistically significant (P<0.01). Multiple Comparison showed that the ratio of eosinophils to white cells and the mount of IL-5 positive cells in nasal mucosa and bone marrow of gene therapy group was significantly lower than that of AR group (P<0.05). The ratio of eosinophils to granulocyte (0.124 +/- 0.031) and the expression level of IL-5 [(29.51 +/- 6.68) pg/ml] in peripheral blood [ 0.184 +/- 0.079 and (56.58 +/- 16.80) pg/ml] were significantly lower in gene therapy group than in AR group (P<0.05).

CONCLUSIONSTransnasal administration of liposome- mediated pGEG. mIL-12 could depress the expression of IL-5 in bone marrow, peripheral blood, and nasal mucosa, to influence the proliferation and differentiation of eosinophils and decrease the delivery and transference of eosinophils to peripheral blood and nasal mucosa. It may be a new treatment for respiratory tract allergic inflammation.