FIG. 1.

Uncoating of HRV-receptor complexes with the pH. Complexes of HRV16 (A) and HRV3 (B) with bound receptor were first prepared by incubations with 1 (grey bars) and 5 (black bars) μM ICAM-1 at 37°C and pH 8.0 for 30 (A) and 15 min (B) (see Materials and Methods). Viruses were also incubated in the absence (white bars) of the ICAM-1 receptor. Complexes or virions were then diluted five times with ice-cold buffers of the indicated pH and were incubated at 37°C for additional 30 min. The samples were then analyzed by sucrose gradient sedimentation and uncoating determined as described in Materials and Methods. Averages and standard deviations from four and three experiments done with three different virus preparations are presented for HRV16 in the absence of ICAM-1 and at high ICAM-1 concentration, respectively.