Potential therapy of Fc-antigen combination-encoding DNA vaccination in mouse allergic airway inflammation

Asthma research in China: a five-year review

Asthma is one of the most common chronic diseases worldwide with increasing morbidity. China has the largest asthmatic population and is one of the countries with the highest asthma mortality. Fortunately, asthma research in China, both clinical and scientific, has developed markedly over the past few years. This has resulted in significant increases in our understanding of Chinese asthma prevalence, risk factors, control status, pathogenesis, and new prevention or treatment strategies. In this review, the major achievements of asthma research in China from 2008 to 2012 are summarized.

Protection against the allergic airway inflammation depends on the modulation of spleen dendritic cell function and induction of regulatory T cells in mice

Background

Allergen-induced imbalance of specific T regulatory (Treg) cells and T helper 2 cells plays a decisive role in the development of immune response against allergens.

Objective

To evaluate effects and potential mechanisms of DNA vaccine containing ovalbumin (OVA) and Fc fusion on allergic airway inflammation.

Methods

Bronchoalveolar lavage (BAL) levels of inflammatory mediators and leukocyte infiltration, expression of CD_11c⁺CD₈₀⁺ and CD_11c⁺CD₈₆⁺ co-stimulatory molecules in spleen dendritic cells (DCs), circulating CD₄⁺ and CD₈⁺ T cells, Foxp3⁺ in spleen CD₄⁺ T cells and spleen CD₄⁺ T cells were measured in OVA-sensitized and challenged animals pretreated with pcDNA, OVA-pcDNA, Fc-pcDNA, and OVA-Fc-pcDNA.

Results

OVA-Sensitized and challenged mice developed airway inflammation and Th2 responses, and decreased the proliferation of peripheral CD₄⁺and CD₈⁺ T cells and the number of spleen Foxp₃⁺ Treg. Those changes with increased INF-γ production and reduced OVA-specific IgE production were protected by the pretreatment with OVA-Fc-pcDNA.

Conclusion

DNA vaccine encoding both Fc and OVA showed more effective than DNA vaccine encoding Fc or OVA alone, through the balance of DCs and Treg.