Those Crazy Stem Cells

Fascinating stuff in the continuing saga of my neighbor Mark and his battle with cancer:

This morning, Mark asked his transplant doctor how the stem cells get back into the bone marrow to begin growing new blood cells. The doctor replied, “We don’t know. Nobody understands how these stem cells know that they belong in the marrow and that they are to begin producing cells again, but they do. It’s a miracle and we go with it!”