Perhaps the most important advancement that has led to the recent discovery of the EBV receptor, Ephrin A2, in epithelial cells is that pre-treatment of immortalized nasopharyngeal epithelial cells with EGF enhances EBV infection with cell-free virus (at a multiplicity of infection of 1000) by more than 2-fold, reaching up to 45% infection efficiency [57]. The gene discussed is EFNA2; the disease is infection.