Neutrophils are the first line of defence in your body. When bacteria attack they ingest and kill them (phagocytosis). Neutrophils are the most abundant type of white blood cells (WBC). About 60% of WBCs comprise of neutrophils.
They are formed in the bone marrow. They are one of the first cells to be recruited in response to inflammation. Before killing the pathogen, neutrophils discharge a mesh of fibre (neutrophil extracellular trap or NET) that allows the disease causing organism to stick to the outer membrane of the cells. After ingesting it, the neutrophils release a number of proteins that helps to destroy the organism. Neutrophil counts increase during a bacterial infection. Low neutrophil count leads to a pathological condition known as neutropenia, in which victims are at a continuous threat to get infection.