FIG. 3.

Binding of coreconstitutes containing different ratios of HA from X-47 and A/Shangdong to ghosts at neutral pH. Ten nanomoles of fluorescently labeled virosomes was incubated with ghosts (100 μg of protein) in 2 ml of buffer at pH 7.4 and 0°C for 15 min, and then the mixture was centrifuged for 3 min at 16,000 × g. Binding was determined in duplicate measurements as described in Materials and Methods. Error bars are ±1 standard deviation. The results shown are representative of repeated experiments and were obtained with the same batch of ghosts and virosomes. The absolute amount of binding may vary between ghost preparations.