Interestingly, S100A7 gene expression and protein secretion are also upregulated in both epithelial cells and endothelial cells in response to infection of the alveolus chips with H3N2 influenza virus, and this is accompanied by upregulation of other S100 family members, including S100A8, S100A9, and S100A12 (Figs. 3b, d and 8a), which could further augment inflammation. The gene discussed is S100A9; the disease is infection.