Cryptococcal virulence: beyond the usual suspects
J. Clin. Invest. Aaron P. Mitchell, et al. 116:1481 doi:10.1172/JCI28842 [Go to this article.]

Figure 1
Natural C. neoformans infection is initiated after inhalation of airborne spores or cells. After reaching the lung alveoli, the organism is taken up by macrophages into their acidic lysosomes, where the organism divides and disseminates. The report from Rittershaus and colleagues in this issue of the JCI (2) shows that there is a critical extracellular growth phase after the organism reaches the lung, but before uptake by macrophages. In this phase, the organism encounters the neutral pH and physiological (~5%) CO₂ level that characterizes host tissues. Rittershaus et al. find that the fungal surface sphingolipid GlcCer is critical for growth under these specific conditions. Thus GlcCer is required for experimental murine infections that are initiated by inhalation (A), but not for infections initiated by injection (B).