CD4 and allergic disease: With respect to allergy DNA vaccines, recent studies found that targeting an allergen to DCs by encoding DEC‐205 fusion proteins alleviates allergic asthma in mice.36, 37 Interestingly, although non‐targeted allergen also protected from sensitization37, the latter was associated with a TH1 phenotype, while DC targeted vaccination induced reduced levels of IFN‐γ production36, 37 but was associated with elevated numbers of CD4 + CD25 + FoxP3 + T cells37.