FIG 5.

RSV F proteins on the surface of infected cells containing partially cleaved p27 have higher stability of the prefusion conformation. Percentages of RSV-infected cells with double-positive populations (p27+site II or site Ø+site II) after temperature-induced conformational change of F protein on the cell surface are shown. HEp-2 or A549 cells were infected with RSV/A/Bernett or RSV/B/BA (MOI = 0.07), incubated at 36°C, and harvested at 3 dpi. Aliquots of cell suspension were then heated for 10 min at increasing temperatures prior to staining and acquisition by imaging flow cytometry. (A) HEp-2 cells infected with RSV/A/Bernett; (B) HEp-2 cells infected with RSV/B/BA; (C) A549 cells infected with RSV/A/Bernett; (D) A549 cells infected with RSV/B/BA.