FIG. 2.

Immunoreactivity and autofluorescence in astrocytoma cells infected with MVeGFP. GCCM cells were infected with MVeGFP at an MOI of 0.01 for 50 h. The cells were fixed and examined by CSLM for autofluorescence and immunoreactivity. The micrographs represent an 8- to 10-μm composite optical section. The images were obtained in double- or triple-excitation mode. MV antigens were detected with either human SSPE antiserum or a monoclonal antibody which recognizes the MV nucleocapsid protein. EGFP was detected by virtue of its autofluorescence, and the cell cytoskeleton was visualized with a monoclonal antibody specific for tubulin. (A) A single cell infected with MVeGFP. MV antigens, detected with SSPE antiserum (blue), tubulin (red), and EGFP (green), are shown. (B) A single cell infected with MVeGFP (arrow) in close proximity to a large syncytium; MV antigens, detected with SSPE antiserum (blue), tubulin (red), and EGFP (green), are shown. MV antigen was not observed in the single infected cell. (C) Cells in the early stages of MVeGFP infection. MV nucleocapsid antigen (red) and EGFP (green) are shown. Arrow a indicates two EGFP-positive and MV antigen-negative cells. Arrow b indicates an EGFP-positive cell which also stains positive for a small number of MV cytoplasmic inclusion bodies. The three cells indicated by arrows are connected to the syncytium, in which relatively large amounts of viral antigen are detected. Magnification, ×40.