Not without a fair bit of effort. I'd have to run the cables down to the basement and back up 2 floors to my office. Not terribly easy to run new lines in an old house, unfortunately.
Can you position two of the nodes where they have line of sight? Maybe one at the bottom of the stairs and one at the top? That would eliminate interference. If you can't do that, you'll just have to experiment with locations until you get the best coverage.