Figure 1

DENV and JEV focus formation in HeLa cells.
(A) HeLa cells were infected with DENV2 strain 16681 or JEV strain JaOArS982 at 40 focus forming units (FFU)/well. At the indicated days p.i., the foci were detected by immunostaining. The upper figures show macroscopic images and the lower figures show 100× magnified images. The black arrowheads indicate the foci. (B) HeLa cells were infected with DENV1 strain Hawaii, DENV3 strain SLMC-50, DENV4 strain SLMC-318, or JEV strain JaOH0566 at 40 FFU/well. At the indicated days p.i., foci were detected by immunostaining.