Osmosis jones.
Apparently according to skatezy&vax / cellular humor lore;
In one episode skatez and vaxcat go on a small mission outside the body and happen to stumble across a red robot like object that is severely damaged next to a clear dry husk of what happens to be a human white blood cell; both objects found inside a skeleton. this means nearly 12000 years before humans went extinct that the universe of osmosis Jones took place.