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PubMed · 1489917

Locomotion forces generated by a polymorphonuclear leukocyte.

S Usami·S L Wung·B A Skierczynski·R Skalak·S Chien
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Abstract

There have been very few studies which have measured the physical forces generated by cells during active movements. A special micropipette system has been designed to make it possible to observe cell motion within the pipette and to apply a pressure to counter the chemotactic migration of the cell. This provides a direct measure of the locomotion force generated by the cell. The average velocity of forward motion is 0.33 microns/s in the absence of counter-pressure. The application of a positive counter-pressure (C-P) causes a decrease in the velocity of the forward motion of the cell. At 17 cm H2O of C-P, the cell velocity drops to zero and even moves backward with a higher C-P. The results show that the decrement of velocity is linearly related to the magnitude of the C-P with a complete stoppage at a pressure of 17 cm H2O which corresponds to a force of 0.003 dyn. The maximum work rate of the cell is approximately 2.5 x 10(-8) erg/s.

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Biomechanical PhenomenaBiophysical PhenomenaBiophysicsCell MovementChemotaxis, LeukocyteHumansIn Vitro TechniquesN-Formylmethionine Leucyl-PhenylalanineNeutrophilsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

S Usami, S L Wung, B A Skierczynski, R Skalak, S Chien. 1992. Locomotion forces generated by a polymorphonuclear leukocyte.. https://doi.org/10.1016/s0006-3495(92)81745-9

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