qRT-PCR analysis of IFN-γ responses in vaccinated PBMCs after stimulation with either M2e or ompA recall antigen. Chickens (N = 10) were vaccinated with JOL916, JOL2068, JOL2074 or JOL2074 + JOL2076, and PBMCs from vaccinated chickens after 14 days post-immunization were stimulated with either M2e or ompA recall antigen for 24 h and analysed for induction of IFN-γ mRNA transcription by qRT-PCR assay. Results are expressed as fold change in mRNA transcription after antigenic stimulation of immunized PBMCs compared to the naïve PBMCs treated with M2e or ompA antigen. Gene expressions were normalized to GAPDH and mRNA levels at 0 h was used as calibrator. A M2e-specific IFN-γ responses. B ompA-specific IFN-γ responses. Data presented are mean ± SD of five chickens per group. Statistical significance was determined by one-way ANOVA (with Tukey’s multiple comparisons tests). *p < 0.05, ns: non-significant.