Stem Cells and Tissue Engineering

Our research in functionalized biomaterials provides enhanced knowledge of cell-material interactions at nano and microscales in response to integrated physical and chemical stimuli. The breadth of our focus spans the full range of physical dimensions (from nano- to micro- to meso-scale), time span (from femtoseconds to days), and biological dimensions (from molecular to cellular to tissue). We are developing 3D nano/micro-structures to study cardiac cell interactions within 2D and 3D microenvironments with nanoscale control of growth factors and topographic guidance. This work will shed insight into the effects of external signals on biological events involved in development and tissue regeneration, and could provide insight into the desirable characteristics for therapeutic systems to aid cardiac tissue repair and regeneration.

In stem cell engineering, we are focusing on human induced pluripotent stem cells. iPSCs are a promising technology in regenerative medicine as they can be autologously derived, maintain high proliferative capacity, and demonstrate enormous differentiation potential, while also mitigating the ethical concerns associated with the use of embryonic stem cells (ESCs). We are developing 3D scaffolds with nanotextures to study stem cell behavior in such 3D nano-environments. Through precise control of spatial and temporal distributions of biological factors in 3D scaffolds, we are also investigating the interactions of stem cells with extracellular matrix (ECM) proteins at the nanometer length scale, with the ultimate aim of creating advanced, clinically translatable biomimetic scaffolds. Our goal is to repair tissue defects resulting from cancer, trauma, congenital abnormalities, and infections and develop in vitro tissue models for early drug screening.

(Left) Immunofluorescence images showing the biological functionality of the HUVEC seeded scaffolds. (Right) human mesenchymal stem cells seeded on a PEG scaffold with a zero Poisson's ratio.