Назад Cytoplasmic fragment of macrophage (lysosomes, Golgi apparatus)-
Cytoplasmic fragment of a macrophage in pleural milky spot. TEM image. 6,000X.

The cytoplasm of a macrophage is marked by a well-developed system of membrane packages, tubules, and vesicles. Some of them belong to the synthesizing and secreting machinery: endoplasmic reticulum #1, #2, #3, Golgi apparatus #1, #2, #3, #4, and multiple transport vesicles. Other structures are polymorph and provide for endocytosis. These are the early endosome compartment and transport vesicles that are attached to the compartment near the cell surface. These structures also comprise some clathrin-coated vesicles. Late endosomes are closely connected with lysosomes #1, #2, #3, #4 when considering both localization and functions. The diversity of the membrane structures indicates that intracellular transport of various substances is well-developed. Current understanding of intracellular transfer mechanisms emphasizes Golgi apparatus, which is considered to be the principal organelle to determine the general framework of intracellular transport..

In an hour, a macrophage can internalize a membrane surface that is approximately equal to the total plasma membrane surface. Continuous recirculation of membrane fragments is crucial to maintaining the size and shape of cells, as well as the fragments’ return to cell surfaces by exocytosis (secretion).