Daniel Lucas uses microscopy to understand how blood cells are produced in the marrow of the bone and how leukemia inhibits this process. A native Spaniard, he obtained his PhD in Madrid training with Drs. Antonio Bernad and Luis Blanco. Then he moved to New York for postdoctoral training in Paul Frenette’s lab. There he discovered basic mechanisms through which the nervous system regulates blood cell production. He also identified macrophages and megakaryocytes -two types of cells produced by the blood stem cells- as key regulators of those very same blood stem cells. This was the first demonstration that the stem cells were regulated by their own progeny. He established his own research group at the University of Michigan Medical School before being recruited to Cincinnati Children’s Hospital Medical Center. His group has discovered mechanisms that promote faster blood recovery after transplantation and deciphered how several types of blood cells assemble in the bone marrow.