Cell blebbing in confined microfluidic environments

Markela Ibo, Vasudha Srivastava, Douglas Robinson, Zachary R. Gagnon

Research output: Contribution to journalArticle

Abstract

Migrating cells can extend their leading edge by forming myosin-driven blebs and F-actindriven pseudopods. When coerced to migrate in resistive environments, Dictyostelium cells switch from using predominately pseudopods to blebs. Bleb formation has been shown to be chemotactic and can be influenced by the direction of the chemotactic gradient. In this study, we determine the blebbing responses of developed cells of Dictyostelium discoideum to cAMP gradients of varying steepness produced in microfluidic channels with different confining heights, ranging between 1.7 μm and 3.8 μm. We show that microfluidic confinement height, gradient steepness, buffer osmolarity and Myosin II activity are important factors in determining whether cells migrate with blebs or with pseudopods. Dictyostelium cells were observed migrating within the confines of microfluidic gradient channels. When the cAMP gradient steepness is increased from 0.7 nM/μm to 20 nM/μm, cells switch from moving with a mixture of blebs and pseudopods to moving only using blebs when chemotaxing in channels with confinement heights less than 2.4 μm. Furthermore, the size of the blebs increases with gradient steepness and correlates with increases in myosin-II localization at the cell cortex. Reduction of intracellular pressure by high osmolarity buffer or inhibition of myosin-II by blebbistatin leads to a decrease in bleb formation and bleb size. Together, our data reveal that the protrusion type formed by migrating cells can be influenced by the channel height and the steepness of the cAMP gradient, and suggests that a combination of confinement-induced myosin-II localization and cAMP-regulated cortical contraction leads to increased intracellular fluid pressure and bleb formation.

Original languageEnglish (US)
Article numbere0163866
JournalPLoS One
Volume11
Issue number10
DOIs
StatePublished - Oct 1 2016

Fingerprint

Myosin Type II
Microfluidics
Blister
pseudopodia
myosin
Pseudopodia
Buffers
Switches
cells
Dictyostelium
osmolarity
Myosins
buffers
Osmolar Concentration
Dictyostelium discoideum
Fluids
Intracellular Fluid
Pressure
cortex

ASJC Scopus subject areas

  • Medicine(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Cite this

Cell blebbing in confined microfluidic environments. / Ibo, Markela; Srivastava, Vasudha; Robinson, Douglas; Gagnon, Zachary R.

In: PLoS One, Vol. 11, No. 10, e0163866, 01.10.2016.

Research output: Contribution to journalArticle

Ibo, Markela ; Srivastava, Vasudha ; Robinson, Douglas ; Gagnon, Zachary R. / Cell blebbing in confined microfluidic environments. In: PLoS One. 2016 ; Vol. 11, No. 10.
@article{2c7125ec586e4ce79750f072608f9866,
title = "Cell blebbing in confined microfluidic environments",
abstract = "Migrating cells can extend their leading edge by forming myosin-driven blebs and F-actindriven pseudopods. When coerced to migrate in resistive environments, Dictyostelium cells switch from using predominately pseudopods to blebs. Bleb formation has been shown to be chemotactic and can be influenced by the direction of the chemotactic gradient. In this study, we determine the blebbing responses of developed cells of Dictyostelium discoideum to cAMP gradients of varying steepness produced in microfluidic channels with different confining heights, ranging between 1.7 μm and 3.8 μm. We show that microfluidic confinement height, gradient steepness, buffer osmolarity and Myosin II activity are important factors in determining whether cells migrate with blebs or with pseudopods. Dictyostelium cells were observed migrating within the confines of microfluidic gradient channels. When the cAMP gradient steepness is increased from 0.7 nM/μm to 20 nM/μm, cells switch from moving with a mixture of blebs and pseudopods to moving only using blebs when chemotaxing in channels with confinement heights less than 2.4 μm. Furthermore, the size of the blebs increases with gradient steepness and correlates with increases in myosin-II localization at the cell cortex. Reduction of intracellular pressure by high osmolarity buffer or inhibition of myosin-II by blebbistatin leads to a decrease in bleb formation and bleb size. Together, our data reveal that the protrusion type formed by migrating cells can be influenced by the channel height and the steepness of the cAMP gradient, and suggests that a combination of confinement-induced myosin-II localization and cAMP-regulated cortical contraction leads to increased intracellular fluid pressure and bleb formation.",
author = "Markela Ibo and Vasudha Srivastava and Douglas Robinson and Gagnon, {Zachary R.}",
year = "2016",
month = "10",
day = "1",
doi = "10.1371/journal.pone.0163866",
language = "English (US)",
volume = "11",
journal = "PLoS One",
issn = "1932-6203",
publisher = "Public Library of Science",
number = "10",

}

TY - JOUR

T1 - Cell blebbing in confined microfluidic environments

AU - Ibo, Markela

AU - Srivastava, Vasudha

AU - Robinson, Douglas

AU - Gagnon, Zachary R.

PY - 2016/10/1

Y1 - 2016/10/1

N2 - Migrating cells can extend their leading edge by forming myosin-driven blebs and F-actindriven pseudopods. When coerced to migrate in resistive environments, Dictyostelium cells switch from using predominately pseudopods to blebs. Bleb formation has been shown to be chemotactic and can be influenced by the direction of the chemotactic gradient. In this study, we determine the blebbing responses of developed cells of Dictyostelium discoideum to cAMP gradients of varying steepness produced in microfluidic channels with different confining heights, ranging between 1.7 μm and 3.8 μm. We show that microfluidic confinement height, gradient steepness, buffer osmolarity and Myosin II activity are important factors in determining whether cells migrate with blebs or with pseudopods. Dictyostelium cells were observed migrating within the confines of microfluidic gradient channels. When the cAMP gradient steepness is increased from 0.7 nM/μm to 20 nM/μm, cells switch from moving with a mixture of blebs and pseudopods to moving only using blebs when chemotaxing in channels with confinement heights less than 2.4 μm. Furthermore, the size of the blebs increases with gradient steepness and correlates with increases in myosin-II localization at the cell cortex. Reduction of intracellular pressure by high osmolarity buffer or inhibition of myosin-II by blebbistatin leads to a decrease in bleb formation and bleb size. Together, our data reveal that the protrusion type formed by migrating cells can be influenced by the channel height and the steepness of the cAMP gradient, and suggests that a combination of confinement-induced myosin-II localization and cAMP-regulated cortical contraction leads to increased intracellular fluid pressure and bleb formation.

AB - Migrating cells can extend their leading edge by forming myosin-driven blebs and F-actindriven pseudopods. When coerced to migrate in resistive environments, Dictyostelium cells switch from using predominately pseudopods to blebs. Bleb formation has been shown to be chemotactic and can be influenced by the direction of the chemotactic gradient. In this study, we determine the blebbing responses of developed cells of Dictyostelium discoideum to cAMP gradients of varying steepness produced in microfluidic channels with different confining heights, ranging between 1.7 μm and 3.8 μm. We show that microfluidic confinement height, gradient steepness, buffer osmolarity and Myosin II activity are important factors in determining whether cells migrate with blebs or with pseudopods. Dictyostelium cells were observed migrating within the confines of microfluidic gradient channels. When the cAMP gradient steepness is increased from 0.7 nM/μm to 20 nM/μm, cells switch from moving with a mixture of blebs and pseudopods to moving only using blebs when chemotaxing in channels with confinement heights less than 2.4 μm. Furthermore, the size of the blebs increases with gradient steepness and correlates with increases in myosin-II localization at the cell cortex. Reduction of intracellular pressure by high osmolarity buffer or inhibition of myosin-II by blebbistatin leads to a decrease in bleb formation and bleb size. Together, our data reveal that the protrusion type formed by migrating cells can be influenced by the channel height and the steepness of the cAMP gradient, and suggests that a combination of confinement-induced myosin-II localization and cAMP-regulated cortical contraction leads to increased intracellular fluid pressure and bleb formation.

UR - http://www.scopus.com/inward/record.url?scp=84992083575&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84992083575&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0163866

DO - 10.1371/journal.pone.0163866

M3 - Article

C2 - 27706201

AN - SCOPUS:84992083575

VL - 11

JO - PLoS One

JF - PLoS One

SN - 1932-6203

IS - 10

M1 - e0163866

ER -