FIG 4.

Binding of parental and heterologous gO recombinant HCMV to fibroblasts. Extracellular HCMV TR, ME, or MT or the corresponding heterologous gO recombinants were applied to nHDF for 20 min. Multiplicities (genomes/cell) wer as follows: TR background viruses, 1 × 10⁴; ME background viruses, 5 × 10⁴; and MT background viruses, 1 × 10⁴. After unbound virus was washed away, cultures were fixed and permeabilized with acetone and cell-associated virus particles were detected by immunofluorescence using antibodies specific for the capsid-associated tegument protein pp150. Cells were visualized by staining nuclei with DAPI. (A) Representative fields of parental TR, ME, and MT and heterologous gO recombinants that consistently reduced binding in 3 independent experiments (Table 2). (B) Mean particles per cell for representative experiments. Error bars represent SD. Asterisks indicate P values of ≤0.05, determined by one-way ANOVA with Dunnett’s multiple-comparison test comparing each recombinant to the parent.