The electrophoresis of real-time PCR products of RNA extracted from group 3 (Pb) on agarose gel (1.5 %) (M: DNA marker, 100 bp Fermentas, from bottom to top: 100, 200, 300, 400, 500, 600, 700, 800, 900, 1,000 bp). Amplified GAPDH, IL-4 and IFN-γ are seen as 236-bp, 95-bp and 92-bp bands, respectively