Fig. 3.

CTL gene expression primarily by adult stages. RT-PCR was performed on first strand cDNA from L1, L2, L3, adults and eggs of H. polygyrus (top panels), using primers specific for Hp-CTL-1 (left) or β-actin (right). Similarly, cDNA from N. brasiliensis L3, lung L4, adults and eggs was used as a template for Nb-CTL-1 lower panel, left), Nb-CTL-2 (right) or β-actin (centre) primers appropriate for each species of parasite. For Nb-CTL-1/2 amplifications, products were excised and sequenced to verify amplification of the correct transcript.