Colony stimulating factor (CSF) is a kind of cytokine discovered by researchers in the study of hematopoietic cells in vitro. It can stimulate the proliferation and differentiation of pluripotent hematopoietic stem cells and hematopoietic progenitor cells at different stages of development and differentiation, and form corresponding cell colonies in semi-solid medium.
Classification of colony stimulating factors
According to the range of colony stimulating factors, they were named granulocyte CSF (G-CSF), macrophage CSF (M-CSF), granulocyte and macrophage CSF (GM-CSF) and multipotent colony stimulating factor (multi-CSF, also known as IL-3). They are essential stimulants for the development of blood cells. Broadly speaking, all stimulate hematopoietic cytokines can be referred to as CSF, For example, erythropoietin (Epo), which stimulates the production of red blood cells, The stem cell factor (SCF) that stimulates the production of hematopoietic stem cells, Leukaemia suppressor (LIF), which stimulates the generation of embryonic stem cells, and thrombogenin, which stimulates thrombogenesis. These cytokines have colony stimulating activity, in addition, CSF also ACTS on a variety of mature cells, promoting their function to have a heterogeneous effect. With the deepening of the study, it was found that colony-stimulating factor could mobilize the migration of neutrophils from bone marrow to peripheral blood and promote the differentiation and proliferation of neutrophils precursors in bone marrow, enhance the function of neutrophils.
Granulocyte-macrophage colony-stimulating factor (GM-CSF) plays a key role in the development and maturation of dendritic cells (DCS) and the proliferation and activation of T cells, which link innate and acquired immune responses. GM-CSF was expressed in mice treated with melanoma cells. An increase in the number of eosinophil, monocytes, macrophages, and lymphocytes can be observed in the lymph nodes. They led to a sustained anti-tumor response in the mice. GM-CSF was beneficial to the expansion of DC1 population and increased the DC - mediated response to tumor cells. In vitro studies of human myelogenous leukemia cells, GM-CSF not only promotes antigen presentation, but also directs cells to DC phenotypes. GM-CSF is also used to improve neutropenia after induction chemotherapy in elderly patients with acute myelogenous leukemia.
Studies have shown that colony-stimulating factors can stimulate the formation of neutral protease plasminogen activators in macrophages, and GM-CSF and M-CSF can be regarded as pro-inflammatory cytokines. CSF may form an important part of the "CSF network" in inflammatory states, associated with cerebrospinal fluid and the expression and role of the pro-inflammatory cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1). GM-CSF and M-CSF are expressed at higher levels in inflammatory and autoimmune sites, such as synovial fluid in patients with rheumatoid arthritis. There is further evidence linking the IL-23-IL-17 pathway to GM-CSF and G-CSF. Because of the association between inflammatory responses mediated by these other cytokines and certain diseases, such as rheumatoid arthritis, obesity, and cancer, CSF may also be associated with the pathogenesis of several diseases and conditions.