FIG 7.
Hypothetical model of the transmission of EHV-1 from a CD172a+ cell to EC. (A) Interaction of EHV-1 via gD with αVβ3 integrin on the surface of a CD172a+ cell activates the intracellular integrin-mediated PI3K and ERK/MAPK signaling pathways. (B) This activation leads to the upregulation of LFA-1 (αLβ2), VLA-4 (α4β1), and αVβ3 integrin expression on the surface of the infected CD172a+ cell. Thus, activated LFA-1, VLA-4, and αVβ3 integrins can interact with some of their respective endothelial ligands and mediate CD172a+ cell adhesion to EC. (C) Both cell-to-cell contacts and secretion of soluble factors, such as TNF-α, activate the replication of EHV-1 in a CD172a+ cell. (D) These processes facilitate direct transfer of cytoplasmic EHV-1 material from infected CD172a+ cell to adjacent EC.