Fig. 2.

Expression of cytokine mRNA transcripts in total spleen cells of BALB/c, C57BL/6, and C3H/He mice infected with F. hepatica by competitive RT-PCR. (A) Construction and quantification of IL-4 competitor molecule as an internal standard (IS) during competitive RT-PCR. The cDNA synthesized from mouse spleen cells was added to various concentrations of the competitor prior to PCR amplification. The PCR products were resolved by 8% polyacrylamide gel, visualized by ethidium bromide staining, and were quantified by a use of densitometer. After densitometry, the following calculations were performed to determine the molecules/µl of the IL-4 that was 346 bp: [(µg/µl)/(330 µg/µmol/bp×bp IS)]×6.02×10¹⁷ molecules/µmol. We approximated that 330×bp equals the molecular weight of internal standard. Expression levels of mRNA transcripts of IL-4 (B), TNF-α (C), and IL-1β (D) in BALB/c, C57BL6, and C3He mice infected with F. hepatica. Total RNAs were isolated from the spleen cells and were quantified by quantitative competitive RT-PCR. The data represent the mean±SEM of 3 independent experiments. ^aP<0.05 and ^bP<0.01.