In vitro study of monocyte viability during the initial adhesion to albumin- and fibrinogen-coated surfaces.
Surface adherent monocytes and macrophages play a central role in the inflammatory response to biomaterials. In the present study the adhesion, viability and apoptotic changes in material surface adherent monocytes during the first hours of cell-surface interactions in vitro were studied, using tissue culture polystyrene surfaces coated with human albumin and fibrinogen. Human peripheral blood monocytes were enriched by a two-step gradient centrifugation and resuspended (1 x 10(6)/ml) in RPMI with 10% fetal bovine serum. The cells were added to polystyrene surfaces coated with human fibrinogen or albumin and incubated in 37 degrees C (5% CO2, 100% humidity) for 30 min, 1, 2, 3 and 24 h. The adherent cells were stained for early apoptotic changes (exposed phosphatidylserine) and cell death using Annexin-V-fluorescein and propidium iodide staining, respectively. A bi-phasic adhesion was observed on the fibrinogen coated surface, having the highest number of adherent cells after 30 min and 24 h, while the cell number was markedly reduced after 1-3 h. The number of adherent cells on albumin was relatively low after all short time incubations but had reached a high level after 24 h. The number of adherent dead cells was highest after I h on both albumin (approximately 30%) and fibrinogen (approximately 15%). In the 24 h cultures, the viability of adherent cells was high on both surfaces (95-100%). Viable cells staining positive for early apoptotic changes could only be clearly observed on the albumin coated surface, after 30 min of cell-material surface interaction. Cell death, including apoptotic death, thus seems to play an important role during the initial interactions between monocytes and a foreign surface.
Department of Cell and Molecular Biology/Microbiology, Göteborg University, Sweden.
M
M
Werthén
A
A
Sellborn
M
M
Källtorp
H
H
Elwing
P
P
Thomsen
D000418:Albumins; D000818:Animals; D017209:Apoptosis; D001672:Biocompatible Materials / Q000633:toxicity; D002417:Cattle; D002448:Cell Adhesion; D002470:Cell Survival; D005340:Fibrinogen; D006801:Humans; D066298:In Vitro Techniques; D007249:Inflammation / Q000209:etiology / Q000517:prevention & control; D008422:Materials Testing; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000166:cytology*; D013499:Surface Properties
D000418:Albumins; D001672:Biocompatible Materials; D005340:Fibrinogen