Moreover, the three upstream bronchial epithelial cytokines IL-33, thymic stromal lymphopoietin and IL-25 that were previously found to be increased in a viral-induced asthma exacerbation model through RIG-I pathway activation38 were also elevated by the RIG-I pathway in the OVA/LPS asthma model (Figure 5e). This evidence concerns the gene RIGI and asthma.