Điều này là hầu như không đáng ngạc nhiên, vì infoldings nhiều bề mặt tế bào trong quá trình thực bào hoạt động, trong đó lên đến 35% của màng bào tương có thể được quốc tế, rõ ràng đòi hỏi phải tổng hợp số lượng phụ của màng tế bào. | 4 The Encounter with the Phagocytic Cell and the Microbe s Answers 91 to the contraction of actin and myosin filaments muscles anchored to a skeleton of microtubules in the cytoplasm. As outlined above the process is triggered off by the attachment of particles to the receptors on the plasma membrane. Phagocytosis is associated with energy consumption involving oxidation of glucose via the hexosemonophosphate pathway - the respiratory burst. There is a 10-20-fold increase in the respiratory rate of the cell. There is also an increased turnover of membrane phospholipids. This is hardly surprising because the multiple infoldings of the cell surface during active phagocytosis in which up to 35 of the plasma membrane may be internalised obviously requires synthesis of extra quantities of cell membrane. As a result of phagocytosis microorganisms are enclosed in membrane-lined vacuoles in the cytoplasm of the phagocytic cell and subsequent events depend on the activity of the lysosomal granules Fig. . These move towards the phagocytic vacuole phagosome fuse with its membrane to form a phagolysosome and discharge their contents into the vacuole thus initiating the intracellular killing and digestion of the microorganism. The loss of lysosomal granules is referred to as degranulation. The process of ingestion killing and digestion of a nonpathogenic bacterium by polymorphs can be followed biochemically by radioactive labelling of various bacterial components and structurally by electron microscopy. When E. coli are added to rabbit polymorphs in vitro phagocytosis begins within a few minutes. Nearly all polymorphs participate each one ingesting 10-20 bacteria. Polymorph granules then move towards the phagocytic vacuoles and fuse with them delivering their contents into the vacuoles. The pH of the vacuoles becomes acid pH and this alone has some antimicrobial effect. Bacteria are killed in the sense that they can no longer multiply when freed from the phagocytic
