Measurement of hematopoietic stem cell proliferation, self-renewal, and expansion potential.

All stem cells exhibit the capacity and ability to proliferate. This is a fundamental property of stem cells, since it is required not only for self-renewal, but also for expansion and the ability for stem cells to engraft in a patient. The capacity or potential for proliferation by stem cells defines their degree of primitives or stemness. This, in turn, is directly related to stem cell self-renewal. Using a highly sensitive, accurate, and reliable ATP bioluminescence signal detection system that can be multiplexed with other assay readouts, it has been possible to determine three stem cell parameters using a single assay. Using primitive hematopoietic bone marrow stem cells as an example, an in vitro protocol is described that incorporates initially culturing primitive stem cells to induce them into cell cycle, followed by a secondary re-plating step that demonstrates both self-renewal capability and expansion potential.