FIG 3.

Time lapse microscopy analysis of MV infectious-center formation in HAE. HAE were infected from the basolateral surface with MV-GFP. (A) Growth of one infectious center shown at 2-h intervals starting at 39 h postinfection. An arrow in the 39-h panel indicates a single infected cell that infects another cell (at 47 h) and then a third cell (at 49 h). During the entire observation period, there was no visible cytopathic effect, and syncytium formation did not occur. (B and C) Higher-magnification, 10-min interval analyses of intercellular cytoplasmic GFP transfer at ∼48 h postinfection. (B) An inverted fluorescence microscope was used. (C) 3D reconstruction by confocal microscopy. The arrow indicates the point of initial GFP leakage.