Table 1.
Summary of the Invasion Mechanisms of the Different Fungi and Their Host Cell Targets
Figure 1.
Model of Aspergillus fumigatus Interactions with Pulmonary Epithelial Cells and Vascular Endothelial Cells during Angioinvasion and Dissemination
Invasive aspergillosis occurs via the following steps: infection is initiated by the inhalation of small numbers of airborne conidia (A), which adhere to pulmonary epithelial cells (B), and are rapidly endocytosed (C). Within the epithelial cells, the conidia germinate to form hyphae (D), which grow by apical extension and escape from the epithelial cells (E). Next, emergent hyphae penetrate the abluminal surface of endothelial cells (F) and induce endothelial cell damage (G). Hyphal fragments disseminate hematogenously (H) and adhere to the luminal endothelial cell surface (I) before invading these cells (J). Luminal invasion results in endothelial cell damage (K) and extravascular invasion of deep organs (L). Steps (A–E) occur in the pulmonary alveoli, (F–H) in the pulmonary blood vessels, and (I–L) in the systemic blood vessels.