Three-dimensional cellular deformation analysis with a two-photon magnetic manipulator workstation.
The ability to apply quantifiable mechanical stresses at the microscopic scale is critical for studying cellular responses to mechanical forces. This necessitates the use of force transducers that can apply precisely controlled forces to cells while monitoring the responses noninvasively. This paper describes the development of a micromanipulation workstation integrating two-photon, three-dimensional imaging with a high-force, uniform-gradient magnetic manipulator. The uniform-gradient magnetic field applies nearly uniform forces to a large cell population, permitting statistical quantification of select molecular responses to mechanical stresses. The magnetic transducer design is capable of exerting over 200 pN of force on 4.5-microm-diameter paramagnetic particles and over 800 pN on 5.0-microm ferromagnetic particles. These forces vary within +/-10% over an area 500 x 500 microm2. The compatibility with the use of high numerical aperture (approximately 1.0) objectives is an integral part of the workstation design allowing submicron-resolution, three-dimensional, two-photon imaging. Three-dimensional analyses of cellular deformation under localized mechanical strain are reported. These measurements indicate that the response of cells to large focal stresses may contain three-dimensional global deformations and show the suitability of this workstation to further studying cellular response to mechanical stresses.
Huang
Hayden
H
Department of Mechanical Engineering, MIT, Cambridge, Massachusetts 02139, USA.
Dong
Chen Y
CY
Kwon
Hyuk-Sang
HS
Sutin
Jason D
JD
Kamm
Roger D
RD
So
Peter T C
PT
D016475:3T3 Cells; D000818:Animals; D002138:Calibration; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000378:metabolism; D008280:Magnetics; D051379:Mice; D008853:Microscopy / Q000295:instrumentation* / Q000379:methods*; D009130:Muscle, Smooth / Q000378:metabolism; D017785:Photons; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013314:Stress, Mechanical
D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins