A role for iron in the control of TB disease has also been observed in guinea pigs [39]–[41]; the ex vivo infection of splenocytes isolated from protected BCG-vaccinated guinea pigs resulted in down-regulation of iron regulatory genes including the ferritin heavy chain and lactoferrin, and a heightened cytokine/IFNG response, which is similar to the trend reported here. This evidence concerns the gene FTH1 and infection.