Phagocytosis-associated functions in neonatal monocyte-derived macrophages.
Using a Teflon culture system we analyzed different aspects of cell maturation and phagocytic activities in neonatal monocyte-derived macrophages. Morphological and cytochemical characteristics as well as the protein composition of neonatal macrophages were identical with those of adult controls; actin binding protein (265,000 Da), myosin (210,000), alpha-actinin (102,000) and actin (42,000) could be identified in cells from either source. All phagocytic functions were shown to be perfectly normal in neonatal macrophages when compared with adult cells: random migration, chemotactic response to zymosan-activated serum and formyl-methionyl-leucyl-phenylalanine, ingestion, and killing of Staphylococcus aureus, phagocytosis-associated chemiluminescence, production of oxygen intermediates (superoxide anion, O2-; hydrogen-peroxide, H2O2). Phorbol myristate acetate-stimulated O2(-)-generation by 1 x 10(5) macrophages was 11.8 +/- 4.7 nmol/h for neonates, and 10.2 +/- 3.9 for controls; production of H2O2 was 7.6 +/- 3.5 nmol/h in neonatal macrophages and 6.4 +/- 2.8 in adult controls. It is unlikely, then, that the increased susceptibility of human neonates to systemic bacterial infections can be related to an abnormality in the essential phagocyte functions of macrophages.
Speer
C P
CP
Department of Pediatrics, University of Göttingen, Federal Republic of Germany.
Gahr
M
M
Wieland
M
M
Eber
S
S
D002465:Cell Movement; D002469:Cell Separation; D002499:Centrifugation, Density Gradient; D002634:Chemotaxis, Leukocyte; D004591:Electrophoresis, Polyacrylamide Gel; D005312:Fetal Blood / Q000276:immunology*; D006651:Histocytochemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007231:Infant, Newborn; D008264:Macrophages / Q000032:analysis / Q000276:immunology*; D009000:Monocytes / Q000276:immunology*; D010587:Phagocytosis; D013481:Superoxides / Q000378:metabolism
D013481:Superoxides; D006861:Hydrogen Peroxide