An award is made to Texas A&M University to develop new instrumentation for a Brillouin imaging system that will measure the elastic properties of cells and extracellular matrix in a 3D cell culture system. Elastic properties of molecular, sub-cellular and cellular structures play a crucial role in many areas of Biology. A prominent example is in embryonic development, where changes in the elastic properties of cells and extracellular matrix contribute to tissue reorganization necessary for organ development. While mechanical interactions between cells and surrounding matrix plays a critical role in many physiological and pathophysiological processes, measurements within 3D tissues have been difficult. Conventional techniques have limited spatial resolution and/or require physical contact with the sample. Brillouin spectroscopy is truly non-invasive and provides information on the elastic properties of biological samples at the subcellular level. While Brillouin spectroscopy has been widely used for elasticity measurements in inorganic materials, the technique has been very slow to catch on in the biological community due to weak signal and difficulty dealing with light scattering.
This research project builds upon recent advances in spontaneous and coherent Brillouin scattering microscopies that provide more than three orders of magnitude increase in signal, improving spatial resolution and overcoming strong light scattering. The investigators will apply their optimized Brillouin imaging set-up to characterize dynamic changes in the local mechanical properties of collagen matrices caused by internally generated contractile forces as well as externally applied loads. Imaging the time-varying distribution of stiffness in the matrix will shed new light on the local mechanical environment to which cells ultimately respond to regulate their function. In parallel to these important applications, they aim to develop the next generation nonlinear Brillouin imaging to double spatial resolution and increase temporal resolution by 100-fold.