GM-CSF Reporter Cell Line

Description

Granulocyte-macrophage colony-stimulating factor (GM-CSF), also known as colony-stimulating factor 2 (CSF2), is a monomeric glycoprotein secreted by macrophages, T cells, stromal cells, natural killer cells, endothelial cells, and fibroblasts. It is a type of white blood cell growth factor that significantly influences macrophages and eosinophils. GM-CSF stimulates stem cells to produce granulocytes (neutrophils, eosinophils, and basophils) and monocytes. Monocytes migrate to tissues and further mature into macrophages and dendritic cells. Therefore, it is part of the immune/inflammatory cascade, rapidly increasing their numbers by activating a small number of macrophages, which is a key process in fighting infections. GM-CSF also plays a role in mature cells of the immune system. For instance, it enhances neutrophil migration, induces changes in cell surface receptor expression. GM-CSF signaling via signal transducers and transcription activators STATs in cytokine-activated macrophages suppresses fungal survival. It induces zinc deprivation within cells and increases reactive oxygen species production, ultimately leading to zinc starvation and toxicity in fungi. Thus, GM-CSF promotes immune system development and defense against infections.Low-dose GM-CSF signaling triggers the phosphorylation of the GM-CSFR β chain Ser, activating PI3K/Akt to enhance BCL-2 activity accordingly. High-dose signaling triggers GM-CSFR β chain Tyr phosphorylation, leading to JAK/STATs activation, resulting in the upregulation of transcription factors PU.1 and IRF4, and downregulation of IRF8, thus affecting myeloid cell differentiation and function. GM-CSF activation of JAK2/STATs can also induce the transcription of SOCS proteins, which negatively regulate signal pathways, forming a signal regulation loop. PI3K activation can also promote monocyte/macrophage polarization by preferentially activating Akt1 and Akt2.The GM-CSF Reporter Cell Line is a reporter gene cell line constructed based on the JAK2/STATs signaling pathway. When GM-CSF binds to GM-CSFR, the receptor β chain is phosphorylated at Tyr, leading to JAK/STATs activation and nuclear entry, resulting in changes in Luciferase expression. Luciferase readings represent the activation effect of the signaling pathway and can be used to evaluate the in vitro effects of GM-CSF-related drugs.