Figure 3. . . No evidence of productive Norwalk virus (NV) replication in 3-dimensional INT-407 aggregates by confocal microscopy analysis of viral proteins. Three-dimensional INT-407 aggregates 24 h post inoculation (hpi) (panels A, B) and 48 hpi (panels C, D) with live NV, 24 hpi with inactivated NV (panels E, F), or phosphate-buffered saline alone controls (panels G, H). Aggregates were stained for viral capsid protein 1 (VP1) (panels A, C, E, G) or nonstructural protein VPg (panels B, D, F, H). Nuclei were counterstained with 4',6-diamidino-2-phenylindole (DAPI) (not shown in print issue). Original magnification ×63.