Listeriosis in diacetoxyscirpenol-treated mice.

Mice were treated with the trichothecene mycotoxin diacetoxyscirpenol (DAS) and subsequently were inoculated intraperitoneally with Listeria monocytogenes. The effect of the mycotoxin on the course of the infection was monitored by observing the resultant mortality and the bacterial content of the spleens from inoculated mice. Mice given 3 mg of DAS/kg of body weight, PO, at days -2 and -1 before inoculation had increased mortality and splenic Listeria counts. In these mice, thymus weights were reduced, and lymphocytes were depleted from the thymus cortex and from splenic lymphoid follicles and periarteriolar lymphoid sheaths. A single dose of 4 mg of DAS/kg given on day 6 before challenge exposure did not affect mortality compared with that in nontreated controls. Mice treated with DAS and subsequently inoculated with Listeria had significantly (P = 0.006) increased neutrophil populations compared with Listeria-infected control mice.