Professional and non-professional phagocytes: an introduction.

摘要: Phagocytosis is the uptake by cell of relatively large particles (>-OS pm) into vacuoles, mechanisms that are clathrin independent and usually re- quire actin polymerization’ J. It trig- gered interaction certain mol- ecules on particle surface with ceptors, lectins or other molecules phagocyte surface. Particles may be recognized directly these receptors, but in many instances recognition mediated opsonins, such as anli- bodies, which coat themselves specific receptorG. The vesicles containing ingested material - phagosomes- ma- ture phagolysosomes, acidic rich hydrolytic enzymes. In Metazoa, phagocytosis underlies degradation microorganisms, damaged senescent cells, particulates pollutants, specialized phago- cytic cells. Thus, phagocytasis cen- tral to host defence against infective agents, tissue remodelling inflammation. Paradoxically, cytosis also a common mechanism ‘ intracellular’ microorganisms invade cells thus avoid direct destruction serum antibodies complementor cytotoxic celW. related pino- cytosis, process responsible for cellular fluid, solutes, col- loids, macromolecules, virusesorsmall particles, bulk internalization plasma membrane. contrast phagocytosis, pinocytosis takes place constitutively, dependent generally does not require polymerization. minimum size necessary trigger maximum has been defined, alone probably only one features deter- mine way taken UP’ ,~. molecular receptor-mediated much better known than those phagocytosis. One reason this ligands quite specific, whereas complex par- ticles bacteria often rec- ognized several some them incompletely characterized. addition, wide range can used study pinocytosis, work primarily performed polymorphonuclear granulocytes (PMNs), monocytes, pri- mary rmacrophage cultures mono- cyte-macrophage-like lines; all difficult transfect, dis- play phagocytic receptors act cooperatively, respond