research

Mark just published a perspicacious perspective on 4D cellular microenvironments in Science Translational Medicine. Reprint is available here.

M.W. Tibbitt and K.S. Anseth, "Dynamic Microenvironments: The Fourth Dimension," Science Translational Medicine, 4, 160ps24 (2012).

Nava showed that the osteogenic differentiation of hMSCs in hydrogels functionalized with phosphate groups can be attributed to serum protein adsorption.

April, now an assistant professor at University of Delaware, and Katie presented a dynamic culture platform in which microwells are patterned and later connected through cytocompatible photocleavage of a poly(ethylene glycol)-based hydrogel to examine matrix geometry effects on cell fate.

Chelsea demonstrated that human Mesenchymal Stem Cells align along topographies patterned on the surface of photodegradable hydrogels. She further showed that cells will dynamically change their cytoskeletal organization in response to a modified topography.

Former group member Cole DeForest, now performing postdoctoral research under David Tirrell, published an excellent review of cutting edge bioactive hydrogel reserach titled "Bioactive Hydrogels for Regenerative Medicine" in Annual Review of Chemical and Biomolecular Engineering.

Abby Bernard showed that pancreatic beta-cells aggregates could be formed in photopolymerized microwell devices. These cell aggregates secreted significantly more insulin per cell than dispersed cells.

A.B. Bernard, C.C. Lin, and K.S. Anseth, "A Microwell Culture Platform for the Aggregation of Pancreatic Beta-Cells," Tissue Engineering Part C-Methods, 18 (8), 583-592 (2012).

Recent Anseth Group Alum Josh McCall showed the that proteins encapsulated in hydrogels formed by radical-mediated thiol-ene polymerization maintain significantly more activity than those encapsulated in gels formed by more traditional acrylate polymerization.

J.D. McCall and K.S. Anseth, "Thiol-Ene Photopolymerizations Provide a Facile Method to Encapsulate Proteins and Maintain their Bioactivity," Biomacromolecules, 13 (8), 2410-2417 (2012).

Sarah Gould showed VICs significantly upregulate alpha-SMA when plated on gels functionalized elastin and collagen mimic peptides as compared with the canonical fibronectin mimic peptide RGD. Furthermore, Sarah showed that alpha-SMA expression, indicative of a disease phenotype, is downregulated in VICs plated on gels versus though on tissue culture plastic.

Malar Azagarsamy demonstrated the light-mediated release of protein from PEG nanogels. He showed the release of active ALP in vitro and that nanogels enter the cell when coupled to TAT peptides.

M.A. Azagarsamy, D.L. Alge, S.J. Radhakrishnan, M.W. Tibbitt, and K.S Anseth, "Photocontrolled Nanoparticles for On-Demand Release of Proteins," Biomacromolecules, 13 (8), 2219-2224 (2012).

Sharon (Huan) Wang shows that valvular interstitial cells will return to a quiescent phenotype after reducing the modulus of the substrate on which they are plated using the nitrobenzyl photochemistry the Anseth group brought into hydrogels. The figure shows the reduction in alpha smooth muscule actin (green) in gels that have been softened.