Phagocytic and motile properties of endothelial cells measured magnetometrically: effects of endotoxin.
Endothelial cells lining the vasculature share some properties with macrophages and neutrophils in that they can take up material from the blood and are known to migrate, particularly during wound healing. We observed that endothelial cells isolated from bovine pulmonary arteries ingested magnetic iron oxide particles during culture in vitro. Using a non-optical, magnetometric method, we examined motions of magnetic-particle containing intracellular vacuoles. We demonstrated that these organelles move within endothelial cells, but at a slower rate than phagosomes within macrophages. Magnetometry was used to show that incubation with endotoxin (10 micrograms/ml) for 4 hr resulted in a decrease in cytoplasmic movement; yet the fluidity of the cytoplasm was increased, as measured by intracellular particle response to forced motion. We conclude that intracellular magnetic probe particles can detect vesicular motion in endothelial cells, and that endotoxin exposure can affect endothelial cells directly, altering their physical properties; these alterations precede ultrastructural evidence of cell death.
Valberg
P A
PA
Department of Environmental Science and Physiology, Harvard School of Public Health, Boston, MA.
Meyrick
B
B
Brain
J D
JD
Brigham
K L
KL
D000818:Animals; D002417:Cattle; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D004731:Endotoxins / Q000633:toxicity*; D008280:Magnetics; D008854:Microscopy, Electron; D015388:Organelles / Q000187:drug effects; D010587:Phagocytosis / Q000187:drug effects*
D004731:Endotoxins