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Viscoelastic behaviour of human mesenchymal stem cells.

Tan SC, Pan WX, Ma G, Cai N, Leong KW, Liao K - BMC Cell Biol. (2008)

Bottom Line: Under a room temperature of 20 degrees C, the instantaneous and equilibrium Young's modulus, E0 and Einfinity, were found to be 886 +/- 289 Pa and 372 +/- 125 Pa, respectively, while the apparent viscosity, mu, was 2710 +/- 1630 Pa.s. hMSCs treated with cytochalasin D up to 20 microM at 20 degrees C registered significant drop of up to 84% in stiffness and increase of up to 255% in viscosity.At the physiological temperature of 37 degrees C, E0 and Einfinity have decreased by 42-66% whereas mu has increased by 95%, compared to the control.Its viscoelstic behaviour are dependent on the structural integrity of the F-actin filaments and temperature.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457, Singapore. tanc0101@ntu.edu.sg

ABSTRACT

Background: In this study, we have investigated the viscoelastic behaviour of individual human adult bone marrow-derived mesenchymal stem cells (hMSCs) and the role of F-actin filaments in maintaining these properties, using micropipette aspiration technique together with a standard linear viscoelastic solid model.

Results: Under a room temperature of 20 degrees C, the instantaneous and equilibrium Young's modulus, E0 and Einfinity, were found to be 886 +/- 289 Pa and 372 +/- 125 Pa, respectively, while the apparent viscosity, mu, was 2710 +/- 1630 Pa.s. hMSCs treated with cytochalasin D up to 20 microM at 20 degrees C registered significant drop of up to 84% in stiffness and increase of up to 255% in viscosity. At the physiological temperature of 37 degrees C, E0 and Einfinity have decreased by 42-66% whereas mu has increased by 95%, compared to the control. Majority of the hMSCs behave as viscoelastic solid with a rapid initial increase in aspiration length and it gradually levels out with time. Three other types of non-typical viscoelastic behavior of hMSCs were also seen.

Conclusion: hMSCs behave as viscoelastic solid. Its viscoelstic behaviour are dependent on the structural integrity of the F-actin filaments and temperature.

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Related in: MedlinePlus

Micropipette aspiration of hMSCs at room temperature. Images (A-D) are displayed at time t = 1 s, 15 s, 100 s and 200 s after the application of step aspiration pressure, respectively. An initial jump of cell protrusion (A) into the micropipette in response to a step aspiration pressure is followed by an asymptotic creep behavior and eventually reaching equilibrium.
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Figure 1: Micropipette aspiration of hMSCs at room temperature. Images (A-D) are displayed at time t = 1 s, 15 s, 100 s and 200 s after the application of step aspiration pressure, respectively. An initial jump of cell protrusion (A) into the micropipette in response to a step aspiration pressure is followed by an asymptotic creep behavior and eventually reaching equilibrium.

Mentions: Upon the application of a step pressure to a hMSC at the control temperature of 20°C, the aspiration length showed an initial jump, followed by a gradual increase, and eventually reached its equilibrium length after 100 s (Fig. 1). This observation demonstrated that hMSCs exhibit a typical monotonic viscoelastic behaviour as do many other engineering materials, which was confirmed by a very high mean correlation coefficient of R2 = 0.98 when the aspiration length-time data were fitted with a viscoelastic solid model (Fig. 2). The instantaneous Young's modulus, E0, the equilibrium Young's modulus, E∞, and the apparent viscosity, μ, of hMSCs obtained were: 886 ± 289 Pa, 372 ± 125 Pa and 2700 ± 1600 Pa·s, respectively (Figs. 3 and 4).


Viscoelastic behaviour of human mesenchymal stem cells.

Tan SC, Pan WX, Ma G, Cai N, Leong KW, Liao K - BMC Cell Biol. (2008)

Micropipette aspiration of hMSCs at room temperature. Images (A-D) are displayed at time t = 1 s, 15 s, 100 s and 200 s after the application of step aspiration pressure, respectively. An initial jump of cell protrusion (A) into the micropipette in response to a step aspiration pressure is followed by an asymptotic creep behavior and eventually reaching equilibrium.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2500016&req=5

Figure 1: Micropipette aspiration of hMSCs at room temperature. Images (A-D) are displayed at time t = 1 s, 15 s, 100 s and 200 s after the application of step aspiration pressure, respectively. An initial jump of cell protrusion (A) into the micropipette in response to a step aspiration pressure is followed by an asymptotic creep behavior and eventually reaching equilibrium.
Mentions: Upon the application of a step pressure to a hMSC at the control temperature of 20°C, the aspiration length showed an initial jump, followed by a gradual increase, and eventually reached its equilibrium length after 100 s (Fig. 1). This observation demonstrated that hMSCs exhibit a typical monotonic viscoelastic behaviour as do many other engineering materials, which was confirmed by a very high mean correlation coefficient of R2 = 0.98 when the aspiration length-time data were fitted with a viscoelastic solid model (Fig. 2). The instantaneous Young's modulus, E0, the equilibrium Young's modulus, E∞, and the apparent viscosity, μ, of hMSCs obtained were: 886 ± 289 Pa, 372 ± 125 Pa and 2700 ± 1600 Pa·s, respectively (Figs. 3 and 4).

Bottom Line: Under a room temperature of 20 degrees C, the instantaneous and equilibrium Young's modulus, E0 and Einfinity, were found to be 886 +/- 289 Pa and 372 +/- 125 Pa, respectively, while the apparent viscosity, mu, was 2710 +/- 1630 Pa.s. hMSCs treated with cytochalasin D up to 20 microM at 20 degrees C registered significant drop of up to 84% in stiffness and increase of up to 255% in viscosity.At the physiological temperature of 37 degrees C, E0 and Einfinity have decreased by 42-66% whereas mu has increased by 95%, compared to the control.Its viscoelstic behaviour are dependent on the structural integrity of the F-actin filaments and temperature.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457, Singapore. tanc0101@ntu.edu.sg

ABSTRACT

Background: In this study, we have investigated the viscoelastic behaviour of individual human adult bone marrow-derived mesenchymal stem cells (hMSCs) and the role of F-actin filaments in maintaining these properties, using micropipette aspiration technique together with a standard linear viscoelastic solid model.

Results: Under a room temperature of 20 degrees C, the instantaneous and equilibrium Young's modulus, E0 and Einfinity, were found to be 886 +/- 289 Pa and 372 +/- 125 Pa, respectively, while the apparent viscosity, mu, was 2710 +/- 1630 Pa.s. hMSCs treated with cytochalasin D up to 20 microM at 20 degrees C registered significant drop of up to 84% in stiffness and increase of up to 255% in viscosity. At the physiological temperature of 37 degrees C, E0 and Einfinity have decreased by 42-66% whereas mu has increased by 95%, compared to the control. Majority of the hMSCs behave as viscoelastic solid with a rapid initial increase in aspiration length and it gradually levels out with time. Three other types of non-typical viscoelastic behavior of hMSCs were also seen.

Conclusion: hMSCs behave as viscoelastic solid. Its viscoelstic behaviour are dependent on the structural integrity of the F-actin filaments and temperature.

Show MeSH
Related in: MedlinePlus