Phagocytosis is the capture, ingestion and destruction by a cell of particles or other cells. Phagocytosis ability is characteristic of certain cells, called phagocytes, like neutrophils and macrophages cells.
By phagocytosis pathogens are destroyed by the macrophages of immune system. Often these agents must be marked by antibodies to be recognized by phagocytes, leukocytes and lymphocytes.
Stages
1. Adherence -membrane of phagocytic cell adheres to the membrane of particle to be ingested; this phase is due to lectins on the surface of micro-organisms;
2. Ingestion -invagination of foreign particle ;
3. Digestion - performed by intercellular enzymes.
Phagocytosis is often accompanied by an abrupt rise in cellular oxygen consumption. Oxygenated compounds formed (H2O2, OH • radicals and O2) are in a very high concentration , where carries toxic effects for organisms ingested. Nitrogen monoxide formed leads tobacteria,parasites and fungi destroy.
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