Virus binding is reduced by high salt or polyethylene glycol and is lost if binding via gH and gp150 is abrogated. (A) gH-null virus was either added to NOK cells for 1h on ice and then cells were washed with salt or Tween 20 as indicated (left panel) or virus was preincubated with polyethylene 6,000 (PEG 6,000) before adding to cells (right panel). Virus (BamK) and cell (CRP) DNA were measured by QPCR. (B) Virus that was gH-null, gp150-null virus or gp150-null and preincubated with soluble αvβ8, as indicated, was added to NOK cells for 1 h on ice. Cells were washed and virus (Bam K) and cell (CRP) DNA were measured by QPCR. Virus copies (v.c.). Error bars are calculated as the standard quotient error. Each experiment was repeated 3 times.