Fig 5. Bile acid (BA) promotion of SADS-CoV replication is dependent on lipid rafts.

(A) Porcine intestinal enteroid (PIE) monolayers were pretreated with MβCD for 1 h, and then MβCD and cholic acid (CA) were added to the medium at the indicated concentration during and after SADS-CoV-GFP infection for 48 h. (B) PIE monolayers were pretreated with 1 mM MβCD for 1 h and supplemented with 1 mM cholesterol for 1 h, and then infected with SADS-CoV-GFP, CA and cholesterol were present during and post SADS-CoV-GFP infection. MβCD and CA-treated monolayers without cholesterol replenishment were set up as control. (C) PIE monolayers were treated with either medium alone, 100 μM CA, 100 μM UDCA or 1 mM propionate. Endocytic vesicles (red) were labeled by FM1-43FX and nuclei (blue) were visualized by DAPI (scale bar, 10 μm). Images were acquired by an LSM880 confocal laser-scanning microscope (Zeiss). Data are from three independent experiments; P values were determined by unpaired two-tailed Student’s t test. *: p < .05; **: p < .01; ns, not significant.