Figure 6

Gene expression in inoculated chickens 4 days after challenge with wild-type S . Enteritidis. Chickens were inoculated on day of hatch with SPI1, SPI2, phoP and aroA S. Enteritidis mutants, challenged on day 22 of life and euthanized 4 days later. Heat map shows average gene expression in groups of chickens. Group I of genes represents genes belonging mainly to innate immune response, group II genes belonging to Th1 cell mediated immune response and group III is mainly associated with B-lymphocyte development and antibody production. Asterisks indicate statistically significant difference from the non-infected chickens at P ≤ 0.05 (*), P ≤ 0.01 (**) or P ≤ 0.001 (***). Maximal fold increase is shown to highlight the differences between the green and red color range for each of the gene. Minimal and maximal expression levels are shown to remind that higher fold inductions are more frequent for genes with a lower basal expression.