Whether the low IP-10 production in the current study might be related to deficiencies in other type of IFN (for example, IFN-λ) warrants further investigated as there is evidence that IFN-λ can induce IP-10 production.34 Bafilomycin inhibited HRV-induced IFN-α, IFN-β and IP-10 production in those with asthma (Figure 6), similar to the results seen in healthy subjects (Figure 4), suggesting that there is no gross deficit in endosomal function in asthma. This evidence concerns the gene IFNA1 and asthma.