Importing legacy domain model written in standard c++

Hello you all
I'm looking some advices about importing c++ set of classes into QT models.

The legacy domain model is formed by classes composed that contains pointers to children classes, std::list of class pointers as collection of child objects, and so on.. There is no a persistence framework, they are implemented using pure c++ classes.

I want to import this domain model into my widgets, datagrids, and the QT MVC paradigm.

Which should be the best steps to acquire those classes into my model , keeping them separates from my code? The domain model comes from a proprietary DLL and I can't modify its sources.

thanks in advance