FIG. 4.

IEO monolayers of PDL-PA hydrogels display appropriate cellular differentiation and polarization and are infectable with norovirus. (A) Analysis of the cellular composition of the IEOs by qRT-PCR reveals multilineage differentiation with no significant differences between cells grown on hydrogels and cells grown on TCP in 96-well plates (p > 0.05). Expression levels of each gene are shown relative to GAPDH. (B) Immunofluorescent staining for markers of differentiated intestinal epithelial cells demonstrates that IEOs cultured on hydrogels contain all the major cell types found in native intestinal epithelium. (C) Cross-sectional views of these monolayers reveal appropriate apicobasal polarization with prominent microvilli (actin and villin) and a robust brush border (sucrase isomaltase) after 5 days of differentiation, scale = 50 μm, vertical slice depth = 0.65 μm. (D) Quantification of noroviral replication following a 24 h infection demonstrates that IEOs grown on hydrogel scaffolds are capable of supporting infection equivalent to IEOs grown on TCP in 96-well plates. TCP, tissue culture plastic. Color images are available online.