Figure 4  .

Effect of treatment with interferon gamma on the survival of Salmonella in primary human fibroblasts. Seven cell lines were infected with Salmonella enterica and then treated with 1000 IU/ml of interferon gamma or left untreated. The three HLA B27 positive cell lines are displayed with square symbols, the four HLA B27 negative cell lines with round symbols. Using ANOVA to compare treated and untreated cells treatment effect (p<0.001) and interaction (p<0.0001) were significantly different.