Increased sensitivity to tryptophan bioavailability is a positive adaptation by the human strains ofChlamydia pneumoniae

摘要: One of the most significant activities induced by interferon-gamma against intracellular pathogens is induction IDO (indoleamine 2,3-dioxygenase) expression, which subsequently results in depletion tryptophan. We tested hypothesis that human strains Chlamydia pneumoniae are more sensitive to tryptophan limitation than animal C. strains. The were significantly IFN-γ a lung epithelia cell model (BEAS-2B), with exposure 1Uml-1 resulting complete loss infectious yield strains, compared where reductions progeny around 3.5-4.0 log. Strikingly, ability form production was completely rescued removal and addition exogenous for but not In fact, heart strain capable entering non-infectious, viable persistent stage when exposed also effectively rescued, respiratory strain. Exquisite susceptibility IFN-γ, specifically due availability appears be core adaptation may reflect chronic nature their infections this host.