Cell signalling pathways that mediate haematopoietic stem cell specification.

Haematopoiesis is one of the most intensively studied and best described systems in the body. However, knowledge of cell signalling pathways that drive haematopoietic stem cell (HSC) development and how they interact with each other and with transcription factors that specify HSCs is still rudimentary. In this review, we will highlight recent advances in the field relating to these questions and identify gaps that need to be filled. To this end, we will briefly describe the developmental ontogeny of HSCs and examine in detail the cell signalling pathways that have been implicated in HSC specification. In conclusion we will discuss how this knowledge has led to the generation of blood cells in the laboratory and consider the implications of that advancement.