blood_and_immune_upper_slim has plasma membrane part granulocyte neutrophil polymorphonuclear leukocyte neutrophilic leucocyte neutrophil leukocyte polynuclear neutrophilic leucocyte Neutrophils are an essential component of the human immune system and belong to the category of white blood cells known as granulocytes. They constitute approximately 50-70% of all white blood cells, making them the most abundant type of immune cells in mammals. Neutrophils develop in the bone marrow from hematopoietic stem cells before being released into the bloodstream where they circulate before migration into tissues, thereby exhibiting a multi-step process that includes margination, rolling, adhesion, and transmigration. Phenotypically and functionally, neutrophils represent a heterogeneous cell population. They are the immune system’s immediate responders and are the first cells to migrate towards the site of an infection. They play a critical role in defending the body from potential pathogenic bacteria and fungi. Their primary mechanism of action involves phagocytosis, where they engulf and destroy these microbes. Neutrophils are characterized by the presence of large quantities of granules containing antimicrobial proteins and enzymes, including defensins and myeloperoxidase, which are released once the cell has recognized and attached to the microbes. The enzymes and other antimicrobial agents can also be released into the surrounding environment, a process known as degranulation. Neutrophils also possess the unique biological ability to eliminate pathogens through a process called neutrophil extracellular trap (NET) formation, or NETosis. In this process, neutrophils release a mixture of DNA, histones, and granule proteins that form a web-like structure which traps and kills microbes. Notably, this process usually leads to the death of the neutrophil itself, referred to as cell suicide or programmed cell death. Neutrophils play a crucial role in the immune system by rapidly responding to infections and inflammation, excessive or dysregulated neutrophil activity can contribute to tissue damage and chronic inflammation, exacerbating various diseases such as rheumatoid arthritis, and neutrophils may contribute to tumor growth and progression. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) Any of the immature or mature forms of a granular leukocyte that in its mature form has a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. poly neutrophil leucocyte ZFA:0009327 polymorphonuclear leucocyte PMN neutrophilic leukocyte BTO:0000130 neutrocyte CALOHA:TS-0688 polymorphonuclear neutrophil https://cellxgene.cziscience.com/cellguide/CL_0000775 FMA:62860 MESH:D009504 polynuclear neutrophilic leukocyte Homo sapiens low affinity immunoglobulin gamma Fc region receptor II leukosialin