Intracellular multiplication of B. suis 1330 wild-type (•), of an isolated, spontaneously erythritol-tolerant mutant of B. suis ΔeryC (○), and of the ΔeryC deletion mutant (▵) in human THP-1 cells. The experiment was performed twice in triplicate (each), and results of one of the experiments are shown, presented as the means ± SD.