Like wild-type PV strains, OPVs initiate cellular infection via binding to the poliovirus receptor (PVR, CD155), a cell adhesion molecule (CD155) highly expressed along the epithelial surfaces of the human alimentary tract and on key antigen presenting cells (APCs), including microfold (M cells) and dendritic cells (DCs), which are both permissive to PV infection(11, 12). The gene discussed is PVR; the disease is infection.