Reduction of virus shedding and replication in AIV H9N2-challenged chickens co-administeredS. entericaserovar Typhimurium expressing chIFN-α and chIL-18 followed by AIV H9N2 vaccination. (A) Virus shedding of vaccinated chickens after AIV H9N2 challenge. Groups of chickens co-administered S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 (109 and 1011 cfu/chicken) followed by inactivated AIV H9N2 vaccination were intratracheally challenged with AIV H9N2 (1010.83 EID50/bird). Amounts of AIV H9N2 in cloacal swab samples taken at the indicated dates post-challenge were determined by real-time qRT-PCR using primers specific for hemagglutinin protein of AIV H9N2. Data represent the average and SEM of five chickens per group. (B and C) The amount of virus in tissues of AIV H9N2-challenged chickens. Groups of chickens that were co-administered S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 (109 and 1011 cfu/chicken) followed by inactivated AIV H9N2 vaccination were euthanized 4 (B) and 7 days (C) after AIV H9N2 challenge. Real-time qRT-PCR using total RNA extracted from tissues (trachea, lung, brain, cecal tonsil, spleen, and kidney) was conducted to determine AIV H9N2 amounts. Data show the average and SEM of AIV H9 fold expression obtained from four chickens per group, after normalized to GAPDH. **p < 0.01; ***p < 0.001 compared to vehicle group that was treated with control bacteria. ¶p < 0.05 compared to chIFN-α-treated chickens. †p < 0.05 compared to chIL-18-treated chickens.
Rahman et al. BMC Veterinary Research 2012 8:105 doi:10.1186/1746-6148-8-105