List of abbreviations
of micros-
specialist terms
explained in
English +

Every attempt was made to provide correct information and labelling, however any liability for eventual errors or incompleteness is rejected!

dieser Seite

Dr. med.
H. Jastrow

of use
Overview macrophages (Macrophagocyti):
Pages with explanations are linked to the text below the images if available! (Labelling is in German)
macrophage with large phagolysosome in con-
nective tissue of lamina propria in stomach (rat)
detail thereof:
phagolysosome 1
 detail 2
phagolysosome 2
detail 2
phagolysosome 3
macrophage, Tela
submucosa gastrici (rat)
detail 1: primary
detail 2: hetero-
macrophage of the
spleen 1 (monkey)
macrophage of the
spleen 2 (monkey)
detail 1 of macrophage
spleen 2 (monkey)
detail 2 of macrophage
spleen 2 (monkey)
macrophage of the
spleen 3 (monkey)
macrophage in loose connective tissue
= histiocyte (rat)
macrophage with hetero-
lysosomes spleen (rat)
macrophages (rat)
macrophage 1 (rat)
macrophage 2 (rat)
alveolar macrophage with primary
and secondary lysosomes (rat)
detail 1: primary lysosome of this
detail 2 showing se-
condary lysosome
macrophage from
thymus (rat)

Macrophages (Terminologia histologica: Macrophagocyti) are cells that "eat" extracellular particles. They are of importance for defense of bacteria and remove foreign bodies, substances and molecules. Further these cells release several factors which influence other cells of the immune system e.g., interleukin-1 which activates and attracts neutrophils.
They further serve for destruction of abnormal cells (tumor, virus infected or overaged cells) e.g., in spleen for elimination of overaged red blood cells which are poor in distorsion. The macrophages grasp particles with their mobile processes (pseudopods) and draw them into their interior whereby the get a limiting membrane deriving form the cell membrane. This procedure is called phagocytosis. Incorporated particles are called phagosomes or endosomes or in case they have more than one layer of outer membrane coat phagophores. Lysosomes fuse with the endosomes to form heterolysosomes = phagolysosomes and their enzymes begin to destruct the content. Phagocytosis is evoked when surface antigens of particles (e.g., viral coat proteins) get in contact with the cell membrane of pseudopods of macrophages. By their mobility one can distinguish either resting macrophages (Terminologia histologica: Macrophagocyti sessiles) or wandering macrophages also called histiocytes (Terminologia histologica: Macrophagocyti mobiles).
Macrophages are also essential for getting rid of degenerating or insufficiently working cells of the body e.g, in spleen where they invaginate and phagocyte old inflexible erythrocytes or they serve to eliminate virus infected cells.
Special types of macrophages that are restricted to defined locations are the microglia cells of the central nervous system, the Kupffer cells attached to the endothelium of the sinusoids of the liver, the alveolar macrophages inside the cavities of the alveols of the lung in order to phagocyte dust particles, the previously mentioned phagocyting reticulum cells in the red pulp of the spleen and the A-synovialozytes located in the synovia of joints (synovial membrane) as well as the peritoneal macrophages patrolling the surface of the peritoneum. All these cells belong to the mononuclear phagocyte system.

--> connective tissue, free cells in connective tissue, blood cells, mast cells, plasma cells, pseudopods, lysosomes, heterolysosomes, phagocytosis
--> Electron microscopic atlas Overview
--> Homepage of the workshop

Some images were kindly provided by Dr. E. Schiller or Prof. H. Wartenberg; other images, page & copyright H. Jastrow.