The organization of extracellular matrices by cells through the exertion of mechanical forces drives fundamental processes such as developmental morphogenesis, wound healing, and the organization of bioengineered tissues. Historically, our ability to investigate cell mechanical behavior has been limited by the technical challenges associated with measuring the sub-cellular origins of cellular force generation and local matrix patterning in a 3-D environment. Thus, our understanding of these fundamental processes is limited, especially in ocular tissues. Over the last several years, our research team has addressed these challenges through the development of new experimental models, use of emerging imaging technologies, and the application of quantitative analysis techniques.
Our in vitro approaches include: 1) models for assessing how specific growth factors expressed following injury or surgery alter the mechanical differentiation of quiescent corneal keratocytes within 3-D collagen matrices, 2) novel approaches for assessing the response of fibroblasts to dynamic changes in ECM mechanical properties (as might be observed during development or wound healing), 3) 3-D constructs for assessing the mechanical interplay between fibroblast migration, sub-cellular force generation, and ECM patterning, and 4) engineered substrates that allow investigation of the impact of ECM protein composition, topography and elasticity on cell differentiation and mechanical behavior.
Together, these experimental models are providing unique insights into the underlying biochemical and biomechanical signaling mechanisms controlling corneal fibroblast migration, contraction, and matrix reorganization. This is fundamental information which can not be obtained using standard 2-D culture models, and may eventually lead to improved strategies for modulating cell mechanical activity during wound healing, and for designing artificial matrices and directing cell behavior during corneal tissue engineering.