Fig. 3.

(A) Addition of pentoxifylline to virus-infected porcine stable kidney (PS) cells was staggered (see Section 2.6.2 for details). The x-axis represents the various time points at which pentoxifylline was added following adsorption of Japanese encephalitis virus onto PS cells. Note that there was no virus yield (represented as log 50% tissue culture infective dose (TCID₅₀)/mL on the left-hand y-axis) in drug-treated cells (○) until 14 h post infection, after which virus yield steadily increased to attain levels similar to that obtained in untreated cells (●). The right-hand y-axis represents the optical density (OD) values obtained in the JEV antigen capture enzyme-linked immunosorbent assay (ELISA). Soluble JEV antigen was measured in the supernatant fluids obtained at 48 h after the experiment (see Section 2.6.2 for details) in both drug-treated (△) and untreated (▴) cells. Note the absence of soluble antigen in the drug-treated cells until 14 h post infection, after which it was detectable. (B) Detection of JEV-specific antigen using an immunofluorescence assay. It can be observed that JEV-infected monolayers treated with pentoxifylline were positive for viral antigen at all time points post infection (400×).