Figure 3: Effect of Cry1Ac on the mRNA expression of IFN- (a and b) and TGF- (c and d) in mice infected with P. chabaudi AS or P. berghei ANKA. Mice were treated with Cry1Ac protoxin or PBS as a control. One day after the last injection, mice were infected with P. berghei ANKA or P. chabaudi AS. On days 4 and 8 PI (a and c) or days 8 and 18 PI (b and d), three mice from each group were killed, and their splenic mRNA was extracted and retrotranscribed. The cDNA obtained was used to amplify the -actin gene and either IFN- or TGF-β by PCR in the same tube. PCR products were separated on 5% polyacrylamide gels. Bands were analysed by densitometry, and the results are shown as the absorbance of the corresponding cytokine divided by the absorbance of -actin. Data are representative of two separate experiments. Asterisks indicate statistically significant differences between the indicated groups.