How do I update a static mesh in Unreal 4 during movement?

I would like to use UE4 for rendering of a huge world.
During the runtime, I would like to load a mesh from a custom source and update the static mesh in the game.

Could someone give me a hint how to do this?

Thank you!

Ps: Some notes on the background.
I store a scene in OpenVDB as an implicit signed distance field. So I need to extract an iso surface in order to create the mesh. That is why, I cannot use some standard static source files. However, if there is a standard file format for huge (I mean reaaaally huge) scenes in UE4, please let me know.