Abstract
The effects of the trichothecene mycotoxins diacetoxyscirpenol, neosolaniol and T-2 toxin on the replication of herpes simplex virus type 2 (HSV-2) in HEp-2 cells were examined. The 50% inhibitory concentrations for HSV-2 replication were 2.3ng/ml for diacetoxyscirpenol, 52.0ng/ml for neosolaniol, and 1.6ng/ml for T-2 toxin. The addition of these toxins to the cells within 4hr after HSV-2 infection was necessary for the inhibition of the virus replication. Viral polypeptides synthesized in HSV-2-infected cells treated with the toxins were analyzed by immunoblotting using rabbit antiserum to HSV-2. The syntheses of early viral proteins were greatly inhibited when the toxins were added 1 hr after infection, and those of late viral proteins were also inhibited by toxin exposures 4hr through 6hr after infection. The toxins added after the completion of the latter protein syntheses affected the HSV-2 replication insignificantly. However, viral RNA synthesis was not inhibited when the toxins were added 1 hr after infection. These results indicate that trichothecene mycotoxins inhibit HSV-2 replication by blocking viral protein syntheses.
