WPF and ActiveX Controls
For hosting ActiveX controls, WPF relies completely on Windows Forms and its capability to host ActiveX controls. In other words, hosting ActiveX controls inside WPF is a matter of hosting a Windows Forms user control in your WPF element that itself hosts the ActiveX control of your dreams.
If you want to go the other way—that is, hosting WPF as an ActiveX control—you can do so by hosting a WPF control on a Windows Forms User Control as described earlier, because a Windows Forms control can be hosted as an ActiveX control, although this is technically supported only in MFC 7.1+.[124]
[124] * If you need to explore this space, "Hosting Windows Forms Controls in COM Control Containers" at http://www.ondotnet.com/pub/a/dotnet/2003/01/20/winformshosting.html is a place to start (http://tinysells.com/94).