HSPA5 and infection: Again, the uninfected ceca showed less GRP78 and curli staining, as well as less macrophage staining (Supplementary Figure S5(b)), which is consistent with previous studies that showed that STm infection leads to the recruitment of macrophages to the gut.63 These findings were further confirmed using a different fluorophore for F4/80, which has a spectrum farther from the EBBA Biolight 680 used to stain curli, with additional steps to reduce autofluorescence and enhance antigen retrieval for optimized signal-to-noise ratio (Figure 8, Supplementary Methods).