Local nasal immunotherapy: efficacy of Dermatophagoides farinae-chitosan vaccine in murine asthma.
BACKGROUND
Local nasal immunotherapy has been reported to be effective for airway allergic diseases. A biodegradable material, chitosan (CS), has been reported to be safe and effective in allergen delivery. In this study, we tested immunotherapeutic efficiency by intranasal administration of Der f entrapped in CS microparticles to sensitized mice.


METHODS
BALB/c mice were sensitized intraperitoneally with Der f extract absorbed to alum, followed by intranasal treatment with PBS, CS, Der f or Der f-CS nano-vaccine for 6 weeks. The mice were subsequently challenged intranasally with Der f extract for 1 week, and we analyzed their clinical symptoms, antibody expression levels, cytokine levels, T cell proliferation and regulatory T cell numbers.


RESULTS
Mice treated with intranasal Der f-CS nano-vaccine prior to challenge displayed an alleviated spectrum of symptoms including airway hyper-reactivity, lung inflammation and mucus production and had fewer eosinophilic cells in bronchoalveolar lavage fluid (BALF). Interestingly, the cytokine levels in Der f-specific IgE were reduced, but IgA in serum and BALF was increased. We also observed that IL-4 was reduced and IFN-gamma and IL-10 were increased among splenocytes and in BALF, which inhibits Der f-specific T-cell proliferation in splenocytes and increases regulatory T cells in the spleen. However, the mice challenged without intranasal Der f or Der f-CS vaccine treatment developed allergic asthma.


CONCLUSIONS
Our results illustrate that intranasal administration of Der f-CS nano-vaccine plays roles in immunologic protection in murine allergic asthma by inducing regulatory T cells and Th1-type reaction.
Liu
Zhigang
Z
Allergy and Immunology Institute, School of Medicine, Shenzhen University, Shenzhen, PR China. lzg@szu.edu.cn
Guo
Hua
H
Wu
Yiaojiong
Y
Yu
Haiqiong
H
Yang
Haitao
H
Li
Jing
J
D000281:Administration, Intranasal; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D001249:Asthma / Q000276:immunology / Q000517:prevention & control*; D001672:Biocompatible Materials; D048271:Chitosan / Q000276:immunology*; D040001:Dermatophagoides farinae / Q000276:immunology*; D003888:Desensitization, Immunologic; D004195:Disease Models, Animal; D016503:Drug Delivery Systems; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D054118:Nanospheres; D014612:Vaccines
D039741:Antigens, Dermatophagoides; D001672:Biocompatible Materials; D014612:Vaccines; D048271:Chitosan