Article

Shape, F-actin, and surface morphology changes during chemotactic peptide-induced polarity in human neutrophils.

Departamento de Biología Celular e Histología, Facultad de Medicina, Universidad de Granada, Spain.
The Anatomical Record 05/1995; 241(4):519-28. DOI:10.1002/ar.1092410410 pp.519-28
Source: PubMed

ABSTRACT The exposure of human neutrophils to uniform concentrations of chemoattractants, such as N-formyl peptides, induces morphological cell polarization. In this study we report the temporal sequence of changes in cell shape, F-actin, and cell surface morphology during cellular polarization induced by N-formylmethionyl-leucyl-phenylalanine (fMLP) in human neutrophils in suspension.
Neutrophil shape changes induced by 10(-8) M fMLP were observed with DIC microscopy. Size and cellular granularity were analyzed by flow cytometry measuring their forward and side scattered light. To visualize F-actin distribution, neutrophils were labeled with the fluorescence probe FITC-phalloidin, and were examined with fluorescence and confocal laser scanning microscopy. Cell surface morphology was assessed with scanning electron microscopy (SEM).
The stimulation of round-smooth neutrophils with nanomolar concentrations (10(-8) M) of fMLP in suspension induced a temporal sequence of morphological changes during cell polarization, characterized by 1) increase in size as determined by forward angle scattered light, 2) rapid redistribution of F-actin from a diffuse cytoplasmic localization to the cell periphery, and 3) rapid reorganization of cell surface morphological features, with accumulation of plasma membrane in the front of polar cells. Four cell shapes were identified with SEM after stimulation of round-smooth neutrophils: round-ridged, round-ruffled, nonpolar ruffled, and polar cells. These cell shapes were correlated with a cortical localization, focal aggregates, and multipolar distribution of F-actin. In polar neutrophils, F-actin became concentrated in the front of the cell.
These findings show the relation between reorganization of the microfilamentous cytoskeleton and modifications in cell shape and surface features during cell polarization induced after fMLP activation in neutrophils. This approach offers a powerful tool for further analysis of receptor distribution in polarized, motile neutrophils.

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    Jason A Carlyon, Dalia Abdel-Latif, Marc Pypaert, Paige Lacy, Erol Fikrig
    [show abstract] [hide abstract]
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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

cell periphery
 
cell polarization induced
 
cell shape
 
cell shapes
 
cellular granularity
 
cellular polarization induced
 
confocal laser scanning microscopy
 
DIC microscopy
 
flow cytometry
 
human neutrophils
 
morphological changes
 
motile neutrophils
 
multipolar distribution
 
Neutrophil shape changes induced
 
polar neutrophils
 
receptor distribution
 
round-smooth neutrophils
 
scanning electron microscopy
 
suspension induced
 
visualize F-actin distribution