Fig. 4.

Effect of L. acidophilus S-layer protein on PEDV attachment, entry and replication observed by IFA (×100). The fluorescent signals show the corresponding viral titers. (A) PEDV infection alone at 4 °C for 1 h (attchment assay). (B) PEDV-infeced Vero cells at 4 °C for 1 h were pretreated with S-layer protein at 37 °C for 1 h (attchment assay). (C) PEDV infection alone at 37 °C for 1 h (entry and replication assay). (D) PEDV-infeced Vero cells were pretreated with S-layer protein at 37 °C for 1 h (entry and replication assay). (E) Blank cells.