Effect of EGTA treatment of BAEC on BHV-1-GFP infection. Well-differentiated BAEC were treated with 0.1 M EGTA for 10 min or control buffer (PBS). Cells were then exposed to BHV-1-GFP or BRSV-GFP (MOI = 0.1) for 2 h. At 2 dpi (BHV-1-GFP) or 3 dpi (BRSV-GFP), the slices were fixed. Virus-infected cells were visualized by GFP expression (A). Scale bar = 100 μm. Apical release of the viruses pretreated with (open symbols) or without (closed symbols) EGTA. Average and standard deviation from 3 animals (n = 2 each) are shown (B).