Neutrophils are the most abundant white cell in the blood, numbering 2-8x109/L. They are important mediators of the innate immune system and are a key component of inflammatory responses to bacteria and other threats.
Neutrophils are potent phagocytic cells, eating perceived threats to the body. They kill organisms using a respiratory burst.
Primary granules contain lysozyme, hydrolytic enzymes (proteases, phospholipases, elastases, and collagenases), myeloperoxidase
Secondary granules: defensins, lysosyme
Neutrophils have segmented nuclei, with 3-4 segments connected by tapering chromatin strands. Primary granules are large and purple, with secondary granules being small and orange/pink. They are approximately 14 um in diameter.
Neutrophils mature over 5-7 days in the bone marrow and circulate for 7-10 hours before migrating into tissues at sites of local inflammation. There they die within 48 hours. Up to 1010 neutrophils are therefore produced per day through granulopoiesis. Rates increase perhaps tenfold during acute inflammation.
Meylocytes, metamyelocytes, bands, neutrophils
like sending in new recruits, then army cadets, then 12 year olds with baseball bats. a bad situation
Neutropenia is a decreased number of neutrophils.
Febrile neutropenia is a serious condition where the body is under attack and less able to defend itself.
Chronic granulomatous disease (CGD) results from a deficiency of phagocyte NADPH oxidase. This leads to dysfunctional killing of bacteria and fungi, and patients suffer recurrent infection.