In vitro expression, purification and antibody production of Sl SCPx, Sl SCPx-t and Sl SCPx-2 recombinant proteins in a bacterial expression system. (A) In vitro expression and purification of the recombinant proteins; (B-D) immune reaction of Sl SCPx, Sl SCPx-t and Sl SCPx-2 recombinant proteins. The recombinant proteins were purified using the His-tag affinity column. The protein samples (10 μg/lane) were analyzed on 15% SDS-PAGE gel and stained with Commassie Blue R-250. On the western blotting analyses (B-D) the proteins were blotted with the corresponding anti-Sl SCPx antiserium at 1:1,500 dilution. C: control; NP: non-purified; P: purified.