A vacuum-actuated microtissue stretcher for long-term exposure to oscillatory strain within a 3D matrix
Although our understanding of cellular behavior in response to extracellular biological and mechanical stimuli has greatly advanced using conventional 2D cell culture methods, these techniques lack physiological relevance. To a cell, the extracellular environment of a 2D plastic petri dish is artificially flat, extremely rigid, static and void of matrix protein. In contrast, we developed the microtissue vacuum-actuated stretcher (MVAS) to probe cellular behavior within a 3D multicellular environment composed of innate matrix protein, and in response to continuous uniaxial stretch. An array format, compatibility with live imaging and high-throughput fabrication techniques make the MVAS highly suited for biomedical research and pharmaceutical discovery. We validated our approach by characterizing the bulk microtissue strain, the microtissue strain field and single cell strain, and by assessing F-actin expression in response to chronic cyclic strain of 10%. The MVAS was shown to be capable of delivering reproducible dynamic bulk strain amplitudes up to 13%. The strain at the single cell level was found to be 10.4% less than the microtissue axial strain due to cellular rotation. Chronic cyclic strain produced a 35% increase in F-actin expression consistent with cytoskeletal reinforcement previously observed in 2D cell culture. The MVAS may further our understanding of the reciprocity shared between cells and their environment, which is critical to meaningful biomedical research and successful therapeutic approaches.
KeywordsMicrotissue Cell mechanics 3D cell culture Microfabrication
M.W. is supported by OGS (Ontario Graduate Scholarship). The authors acknowledge support from individual NSERC Discovery Grants (M.G. and A.E.P.). A.E.P also acknowledges generous support from the Canada Research Chairs program.
M.W. performed the data acquisition and analysis and wrote the manuscript. All authors contributed to the study design and revised the manuscript.
Compliance with ethical standards
The authors declare no competing financial interests.
- K. L. Billiar, in (Springer, Berlin, Heidelberg, 2010), pp. 201–245Google Scholar
- S. Chagnon-Lessard, H. Jean-Ruel, M. Godin, A.E. Pelling, Integr. Biol. 66, 409 (2017)Google Scholar
- K. Kanda, T. Matsuda, T. Oka, ASAIO J. 39, M686 (n.d.)Google Scholar
- B.D. Lucas, T. Kanade, Proc. 7th Int. Jt. Conf. Artif. Intell. 2, 674 (1981)Google Scholar
- N. Pender, C.A. McCulloch, J. Cell Sci. 100 (1991)Google Scholar
- K.-G. Shyu, Clin. Sci. 116 (2009)Google Scholar
- P.G. Smith, L. Deng, J.J. Fredberg, G.N. Maksym, Am. J. Physiol. Lung Cell Mol. Physiol. 285 (2003)Google Scholar