Herpes simplex virus type 1 (HSV-1) mutants were selected by passage of HSV-1 (KOS) in HEp-2 cells such that binding and penetration occurred in the presence of heparin. Although this mutant adsorbed to the cell surface at the nonpermissive temperature (NPT), it failed to penetrate the cell membrane. Its structure was elucidated to be 3β,12β,20(S)-tri-hydroxydammar-24-ene-3-O-β-d-xylopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 2)-β-d-glu-copyranoside, based on the detailed analyses of the 1D and 2D NMR spectral data and acidic hydrolysis. We find that suramin, like heparin, blocks the binding of HSV-1 to the cell membrane. The effect was maintained under conditions of fusion induced by polyethyleneglycol treatment. The d-OMP had been tagged with a fluorescent marker, a BODIPY (bordifluoropyrromethene) derivative. It takes in far more nations – 52 – than any other military command in history.
Kinetics of entry that included virus attachment and penetration showed that the cell-specific effects can be explained by two distinct phases of attachment that occurred before penetration, but differed in duration on both susceptible cell lines. At any rate, it was certainly not a heavy romantic kiss. However, this phenomenon appeared to be selective since it was not observed with gC oligomers. In addition, we examined the cross-linking patterns of gB and gD in null viruses K082 and KOSgD beta. The 50% effective concentration (EC₅₀) values, determined by plaque reduction assay, were 16.47 ± 0.67 and 19.44 ± 1.16 μM for HSV-1 and HSV-2, respectively, whereas the 50% cytotoxic concentration (CC₅₀) determined by the XTT test on Vero cells was 510.64 ± 4.56 μM. Thus, to by-pass this cellular barrier, we tested if the void spaces resulting from tumor cell apoptosis could enhance the initial spread of oncolytic HSV in tumors.