A myeloid stem cell, also referred to as a myeloblast, is a type of hematopoietic stem cell that resides within the bone marrow. It is responsible for generating various types of mature blood cells known as myeloid cells. These myeloid cells include granulocytes (such as neutrophils, eosinophils, and basophils), monocytes, macrophages, erythrocytes, and platelets.
The myeloid stem cell is considered to be multipotent, meaning it has the ability to differentiate into a limited number of specialized cell types. Unlike other stem cells, such as pluripotent embryonic stem cells, myeloid stem cells have a more restricted lineage commitment.
The process by which a myeloid stem cell differentiates into its progeny involves several stages of maturation. Under appropriate physiological conditions and signaling cues, the myeloid stem cell undergoes proliferation and differentiation into a series of progenitor cells, each with a progressively more restricted potential. Eventually, these progenitor cells give rise to mature, functional myeloid cells.
The role of myeloid cells in the immune system is critical, as they mediate innate immune responses and play a fundamental role in the defense against pathogens and the maintenance of tissue homeostasis. Dysfunction in myeloid cell development or function can lead to various hematological disorders, such as leukemia, myelodysplastic syndrome, and myeloproliferative neoplasms. Studying myeloid stem cells and their differentiation pathways is crucial for understanding normal and abnormal hematopoiesis, as well as developing potential therapeutic approaches for these disorders.
