The viscosity of neutrophils and their transit times through small pores.

Published

Journal Article

Passive neutrophils from five different individuals are rapidly aspirated at constant suction pressure and at room temperature into a pipet with a diameter of 4 microns. The excess suction pressures (i.e., the pressures in excess of the small threshold pressure required to produce continuous flow into the pipet) are 5000, 10,000 and 20,000 dyn/cm2 (0.5, 1 and 2 kPa) and are comparable to those encountered in the microcirculation. The rate of entry into the pipet is modeled with a linearized version of a theory by Yeung and Evans for the newtonian flow of a neutrophil into a pipet or pore. From this theory and measurements of the cell size and its rate of entry into the pipet, we can calculate a value for the cytoplasmic viscosity. A linear (newtonian) fit of the theory to the experimental data gives a value for the viscosity of 1050 poise. A non-linear fit predicts a decrease in the "apparent viscosity" from about 1500 poise at zero excess pressure to 1000 poise at an excess aspiration pressure of 20,000 dyn/cm2. Our experiments and analysis also allow us to calculate a value for the transit time through short pores over a wide range of excess aspiration pressures and pore diameters. For example, for a pore diameter of 3 microns and an aspiration pressure of 1250 dyn/cm2, we predict a transit time of about 70 s. At 6 microns and 20,000 dyn/cm2, the predicted transit time is only about 0.04 s.

Full Text

Duke Authors

Cited Authors

  • Hochmuth, RM; Needham, D

Published Date

  • January 1990

Published In

Volume / Issue

  • 27 / 6

Start / End Page

  • 817 - 828

PubMed ID

  • 2093391

Pubmed Central ID

  • 2093391

Electronic International Standard Serial Number (EISSN)

  • 1878-5034

International Standard Serial Number (ISSN)

  • 0006-355X

Digital Object Identifier (DOI)

  • 10.3233/bir-1990-27603

Language

  • eng