Fig. 2: Cloning, expression, and purification of IL-33 constructs.

a Restriction map of the cloned IL-33 constructs in the pET30a vector. b The positive clones for each IL-33 construct were grown, induced with IPTG, and analyzed via 12% SDS‒PAGE. c SDS‒PAGE profile of the recombinant IL-3395–270, IL-3399–270, and IL-33109–270 proteins after Ni-NTA column purification. d SDS‒PAGE profile of purified recombinant IL-33 proteins after dialysis.