[Research Progress of Single-cell Transcriptome Sequencing Technology in Physiological Hematopoiesis--Review]

Hematopoiesis starts from the embryo and runs through the entire life of a living body, which is a multi-stage and complex dynamic process that is regulated by multiple pathways, involving a variety of cells and hematopoietic anatomical locations. During the development of the mammalian hematopoietic system, the currently known hematopoietic anatomical locations mainly include yolk sac, aorta-gonad-mesonephros, fetal liver, bone marrow, and thymus. The first three are mainly responsible for hematopoiesis during the embryonic and fetal period, while bone marrow is the main place for postnatal hematopoiesis, and thymus is mainly responsible for the differentiation of T lymphocytes. Integrating flow cytometry, in vitro cell culture and in vivo animal transplantation models, early researchers conducted an in-depth analysis of the differentiation pathways of hematopoietic cells. However, due to technical limitations, it is difficult to track the single-cell hematopoietic activity of hematopoietic organs. Transcriptome sequencing at the single-cell level provides researchers with a unique perspective, making it possible to draw the most detailed cell fate transition maps of the hematopoietic development of living organisms, and providing new ideas for the diagnosis and treatment of hematological tumors. In this article, we reviewed the research progress in the use of large-scale single-cell transcriptome sequencing in the field of physiological hematopoiesis in recent years.