enterica serovar Typhimurium expressing swIL-18 and swIFN-α showed the lowest severity of clinical signs. In particular, Tigecycline the clinical score of piglets co-administered Salmonella vaccine expressing swIL-18 and swIFN-α was lower than that of piglets administered Salmonella vaccine expressing either swIL-18 or swIFN-α, with apparent differences at seven days post-challenge
(Table 1). Cumulative daily weight gain was measured to more precisely quantify the alleviation of clinical signs. Consistently, piglets co-administered S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α displayed a significantly increased weight gain, compared to groups that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α (Fig. 4a). However, when changes in body temperature of PrV-infected piglets were monitored, there were no significant differences between the group co-administered with S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α, and the JAK inhibitor group that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α (Fig. 4b). Taken together, these results indicate that co-administration
of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α results in the enhanced alleviation of clinical severity caused by PrV infection, compared to individual administration of S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α. To evaluate the effect of orally co-administered S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α on virus shedding from PrV-infected piglets, the amount of PrV in nasal swabs was determined Interleukin-2 receptor daily in all groups by the use of a
conventional plaque assay from 3 to 14 days post-challenge. PrV shedding was detected from 3 days after PrV infection and peaked at 6 days (Fig. 5). Piglets that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α had lower peak levels of PrV shedding at 6 days post-inoculation, when compared to piglets that received no treatment and S. enterica serovar Typhimurium harboring pYA3560. Furthermore, piglets orally co-administered with S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α showed significantly reduced PrV shedding at 6 days post-challenge compared to those administered S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α. In addition, the co-administration of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α provided a shortened duration of virus shedding. These results indicate that co-administration of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α produced enhanced inhibition of virus shedding from PrV-infected piglets. The present study demonstrates that the co-administration of S.