Interferon gamma (IFN-γ) production by peripheral blood mononuclear cells (PBMC) stimulated with recombinant canine IL-2 or IL-12 produced by COS-7 cells. PBMC of 8 adult mongrel dogs were cultured for 48 h with: complete RPMI 1640 medium alone (M), concanavalin A at 5 mg/mL, supernatant of COS-7 cells transfected with pcDNA3.1-caIL-2 (SN IL-2) at 25% or supernatant of COS-7 cells transfected with pcDNA3.1-sccaIL-12 (SN IL-12) at 0.025, 0.5 or 10%. IFN-γ was assessed in the PBMC supernatants by capture ELISA. Data represent average of duplicates and bars the means obtained for the eight animals. *p < 0.01, Dunnett’s test (p < 0.0001, repeated measures ANOVA).