CDH5 and infection: Given that the in vitro endothelial permeability assay showed enhanced microvascular permeability at 72 hr post-infection and the AFM studies showed a dramatic reduction in the adhesive force between VE-cadherin and endothelial cells at 48 hr, we suggest that upon infection by SFG rickettsiae, phosphorylation of VE-cadherin directly attenuates homophilic protein-protein interactions at the endothelial AJs, leading to endothelial paracellular barrier dysfunction and microvascular hyperpermeability.