*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
Title: Biomaterial-Based Engineering of Dendritic Cell Environments for Targeted Immune Tolerance Induction
Summary: Autoimmune disorders are estimated to be among the top ten leading causes of death among women of all ages below 65, for which available treatments include systemic immunosuppressants that cause serious long-term side effects. There is hence a growing interest to engineer mechanisms of inducing target-specific immune tolerance with biomaterials particularly professional antigen presenting cells namely dendritic cells (DCs). DCs previously studied in the context of biomaterials have been discovered to elicit differential responses to biomaterials suggesting that materials on their own have the ability to stimulate specific DC phenotype. As the phenotype of DCs is a key mediator of downstream adaptive immune responses that lead to normal or aberrant immunity, there is increasing interest in delineating the underlying mechanisms of material-cell interaction. In this proposal, we initially investigate the role played by DCs in the adjuvant effect shown by certain materials such as poly lactic-co-glycolic acid (PLGA) and further exploit the differential nature of the response towards agarose compared to PLGA, to develop solely biomaterial-based methods in inducing antigen-specific immune tolerance in an in vivo mouse model. Moreover, DCs can be locally treated with specific immunomodulators rather than biomaterials to express a tolerogenic phenotype that can trigger antigen-specific immunoregulation. As a second and distinct approach, in this proposal, we examine the possibility of developing the spatiotemporally controlled delivery of immunomodulators from a single implantable biomaterial niche. The design of such a delivery device would call for not only incorporating a strategy for DC phenotype modulation but also a technique for promoting endogenous DC recruitment upon in vivo implantation; thus it would enable the localized delivery of factors while promoting systemic circulation of in situ primed DCs for effective downstream immune function, a feature commonly lacking in existing treatments of autoimmune diseases. Finally, the efficacy of this technique will be assessed in the context of an autoimmune disease model, to explore its potential use as a therapeutic cure for individuals with autoimmune disorders.
Advisor:
Julia E. Babensee, PhD
Wallace C. Coulter Department of Biomedical Engineering
Georgia Institute of Technology and Emory University
Thesis Committee:
Julie Champion, PhD
School of Chemical and Biomolecular Engineering
Georgia Institute of Technology and Emory University
Edward Botchwey, PhD
Wallace C. Coulter Department of Biomedical Engineering
Georgia Institute of Technology and Emory University
Susan Thomas, PhD
George W. Woodruff School of Mechanical Engineering
Georgia Institute of Technology and Emory University
Krishnendu Roy, PhD
Wallace C. Coulter Department of Biomedical Engineering
Georgia Institute of Technology and Emory University