Hanna K.A. Mikkola, M.D., Ph.D.

The main limitation hindering the development of improved blood stem cell therapies is the inability to maintain these cells’ self-renewal capacity and pluripotency in culture. Mikkola studies fetal hematopoietic microenvironments to better understand the mechanisms that regulate the development of blood stem cells and cardiovascular stem/progenitor cells. These insights will be instrumental in researchers’ efforts to expand cord blood or bone marrow blood stem cells, or generate blood stem cells from human embryonic stem cells, to improve therapies for leukemia and other blood cell disorders.

Mikkola defined novel markers to identify developing blood stem cells as they emerge from hemogenic endothelium and expand in fetal niches during mouse and human development and further determined the niche cells and anatomical sites, such as the placenta, that support blood stem cell development. She has also made strides in deciphering the cell-intrinsic mechanisms that govern the specification and self-renewal of blood stem cells and created a single cell map of human blood stem cell development that traces each step in the process by which they are made in the human embryo — providing scientists with a blueprint for producing fully functional blood stem cells in the lab.

The same mechanisms governing the development and self-renewal of blood stem cells are exploited in leukemogenesis, the process wherein mutations in blood stem cells or progenitor cells result in the development of leukemia. Mikkola seeks to identify members of the transcriptional regulatory network that are involved both in normal blood cell development and in blood cancers. Improved understanding of these regulators will unravel the regulatory mechanisms that are disturbed in leukemias and could serve as a foundation upon which new and better treatments for these diseases can be developed.