Abstract:
:Neutrophils rely on rapid changes in morphology to ward off invaders. Time-resolved dynamics of spreading human neutrophils after activation by the chemoattractant fMLF (formyl methionyl leucyl phenylalanine) was observed by RICM (reflection interference contrast microscopy). An image-processing algorithm was developed to identify the changes in the overall cell shape and the zones of close contact with the substrate. We show that in the case of neutrophils, cell spreading immediately after exposure of fMLF is anisotropic and directional. The dependence of spreading area, A, of the cell as a function of time, t, shows several distinct regimes, each of which can be fitted as power laws (A ~ t(b)). The different spreading regimes correspond to distinct values of the exponent b and are related to the adhesion state of the cell. Treatment with cytochalasin-B eliminated the anisotropy in the spreading.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Sengupta K,Aranda-Espinoza H,Smith L,Janmey P,Hammer Ddoi
10.1529/biophysj.105.080382subject
Has Abstractpub_date
2006-12-15 00:00:00pages
4638-48issue
12eissn
0006-3495issn
1542-0086pii
S0006-3495(06)72176-2journal_volume
91pub_type
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