Growth factors and miRNA regulating differentiation of hematopoietic stem cells (HSC) to various blood-related cell types. Note that myeloblasts branch off separately from erythrocytes and megakaryocytes. Adapted from an open access image attributed to ZooFari and Mikael Häggström (http://en.wikipedia.org/wiki/User:Mikael_H%C3%A4ggstr%C3%B6m/Gallery#Medical_collaborations) and augmented from literature and NHLBI Progenitor Cell Biology Consortium (PCBC) collaborators.