Bucky can understand Steve's fear, though he only understands it now after he had gained a horrible experience with doctors that had left him wary of hospitals in general. But this couldn't be ignored, it wasn't normal, and who knew if this would turn out to be somehow dangerous?

He scrubbed his hand over his forehead and looked supremely uncomfortable.

"I real hope so, Steve, you deserve this kind of miracle. But we still have to try and figure out what it is, and if it's safe. I have-- there's someone I know who could help test this without it getting out."

Urgh, he really didn't want to call in this favour. He had worked quite hard to drop off the radar where this particular "friend" was concerned. But for Steve... he'd always done whatever it took for Steve and he always would.