Measuring the Effect of Cell Passage Number on the Elastic and Viscoelastic Properties of Adipose-derived Stem Cells

Investigators: Rafael D. Gonzalez Cruz

Recently, our lab showed that cellular mechanical properties were indicative of differentiation potential of adipose-derived stem cells (ASCs). However, previous studies indicate that passage number affects the differentiation potential of ASCs on two-dimensional substrates. Furthermore, surface marker expression profiles typically used to characterize ASCs changed as passage number increases. Given that passage number changes surface marker profile and differentiation potential in ASCs, we hypothesized the mechanical properties of these cells changed as well as a function of passage number. Therefore, we measured the elastic and viscoelastic properties of ASCs using atomic force microscope-based microindentation testing on single, spherical ASCs from passages 3-5. Our results show that P3 spherical ASCs were more compliant and less viscous than P5 ASCs. Specifically, increased passage result in a less compliant phenotype. These findings suggest that the amount of time ASCs are exposed to environmental signals in their culture environment could be strongly affecting their mechanical properties and their differentiation potential as well. The experimental findings comprising this project have been published in the journal Adipocyte as part of a brief report article and it can be accessed here.