Current Trainees
NIBIB / Biomechanics Training Program

Harry An - Chemical Engineering

B.S., Chemical Engineering, Carnegie Mellon University

Thesis Advisor: Patrick S. Doyle

Thesis Project: Synthetic particles with unique shape and size have been shown to influence many vital bodily processes including phagocytosis, targeting, and circulation. To date, however, few studies have systematically examined the effect of particle deformability on biological function. Consequently, my project will focus on creating anisotropically-shaped, cell-sized bio-mimetic particles with tunable deformability. In particular, I am interested in studying the elasto-hydrodynamic behavior of red blood cell analogs under physiological conditions in microchannels. I will use scaling theory and relevant quantitative measurements to construct a microfluidic model of vascular networks.

Kristin Bernick - Biological Engineering

B.S., Biomedical Engineering, University of California, Davis

Thesis Advisor: Subra Suresh

Thesis Project: Traumatic brain injury is becoming increasingly common in soldiers returning from war. Primary blast waves have been shown to cause mild TBI; however, little is known on the actual mechanism of damage. My thesis project focuses on better understanding this process at the cellular level. My main goals include determining material properties of cells of the central nervous system (neurons and glia) and developing models to simulate how the cells respond to a variety of mechanical forces. In addition, neurons and glial cells will be subjected to various loading mechanisms, including compression and shock waves, and assays will be used to investigate possible damage mechanisms. Better knowledge of the damage mechanism will guide development of better protective gear as well as potential treatments.

Caroline Chopko - Chemical Engineering

BSE, Chemical Engineering, Princeton University

Thesis Advisor: Linda Griffith, Doug Lauffenburger

Thesis Project: Developing a Multiplexed Protease Sensor - My project aims to develop a multiplexed assay to monitor protease activity in long term cell culture. This experimental tool will be used to assess how biomechanical and chemical perturbations affecting individual proteases can perturb a network and also has applications to developing "signatures" of rare cells in a complex cell mixture.

Andrew Koo - Biological Engineering

B.A., Biochemistry and Molecular Biology, Washington University in St. Louis

Thesis Advisor: 1C. Forbes Dewey, Jr., 2Guillermo García-Cardeña
1Hatsopolous Microfluids laboratory, 2Department of Pathology, Harvard Medical School 

Thesis Project: The endothelial glycocalyx layer (EGL) is a thin gel-like layer (400-500 nm in thickness) located above the apical surface of endothelial cells. The glycocalyx has been shown to be a protective shield against arterial disease. I am interested in understanding the mechanotransduction event of how hemodynamic shear stress is transmitted through endothelial glycocalyx and initiate cellular responses such as nitric oxide production.

Yang Li - Biological Engineering

B.S., Chemical Engineering, Georgia Institute of Technology

Thesis Advisor: Alan Grodzinsky
Center for Biomedical Engineering 

Thesis Project: Osteoarthritis (OA) has long been thought to be a disease of wear-and-tear of joint surfaces, in which mechanical forces gradually wear away the cartilage matrix material and expose underlying bone. However, it is now known that there is an immediate increase in the concentration of pro-inflammatory cytokines after an ACL tear. These cytokines can diffuse into the cartilage and upregulate chondrocyte production of proteolytic enzymes that can ultimately destroy cartilage itself. For my project, I'm interested in studying the effects of combined biomechanical and biochemical insult to cartilage explants in an in vitro model.

John Maloney - Materials Science and Engineering

B.S. and M.S., Mechanical Engineering, University of Maryland
M.Eng., Materials Science and Engineering, MIT

Thesis Advisor: Krystyn Van Vliet, Robert Langer
Laboratory for Material Chemomechanics 

Thesis Project: Mesenchymal stem cells, or MSCs, (which live at low concentrations in our tissues) have the ability to self-renew and produce progeny such as muscle and bone cells when extracted and cultured in vitro. The therapeutic possibility of regenerating damaged tissue such as post-heart-attack cardiac muscle has motivated intense study of these cells' characteristics and behavior. I study the mechanics of MSCs: specifically, their deformability when exposed to a load. But the load is not mechanical but photonic; the optical pressure of a laser beam is enough to measurably stretch the cells. This technique, termed "optical stretching," allows us to quantify cell stiffness without ever physically touching the cell. Our goal is to identify unique mechanical markers of MSCs to enable them to be efficiently sorted ex vivo and isolated from their many non-stem-cell neighbors for therapeutic uses.

Eric Soller - Mechanical Engineering

S.B., Mechanical Engineering, Rose-Hulman Institute of Techology
S.M., Mechanical Engineering, MIT

Thesis Advisor: Ioannis V. Yannas
Fibers & Polymers Laboratory 

Thesis Project: Cell-mediated mechanical forces play a critical role in the spontaneous healing of severe wounds in the adult mammal. When a peripheral nerve is transected a thick layer of contractile cells (myofibroblasts) surround and compress the nerve stumps (like a "pressure cuff"), preventing reconnection and resulting in a painful loss of function. There is considerable evidence, uncovered in the MIT Fibers & Polymers Laboratory, that some organs can be induced to regenerate if these forces are cancelled out in a local manner. The "pressure cuff" theory predicts that a transected nerve will heal by regeneration, rather than by contraction and scar formation, if the forces exerted by the myofibroblast capsule have been cancelled in a "local" manner. The goal of my current work is to evaluate this hypothetical mechanism for organ regeneration in vivo using various contraction-blocking strategies and a linear elastic model of the regenerating sciatic nerve. 

Adam Zeiger

Thesis Advisor: Krystyn J. Van Vliet

Thesis Project: In vivo, cell functions are driven largely by molecular interactions at the physical interface that is the cell membrane. Both cell-cell and cell-matrix interactions are critical to the adhesion, proliferation, and migration of cells in both physiological and pathological states, but the mechanisms driving these interactions are not yet fully elucidated. Studies are often conducted in dilute solutions, where inter- and intramolecular reaction rates and protein interactions differ by orders of magnitude from measured in vivo. Furthermore, these studies are conducted for cells adhered to relatively stiff material substrata, such as glass or tissue culture polystyrene. It is increasingly appreciated that there is a close coupling between the chemical and mechanical microenvironments of the cell (i.e., the chemomechanical niche). Therefore, the biochemical reactions and conditions responsible for generating mechanical stresses and attendant cell behaviors may not be well represented in typical in vitro assays. The goal of my research is to determine how chemomechanical changes to the in vitro, extracellular niche (fluids and solids) alter intracellular organization as well as cell-cell and cell-substrata interactions critical to tissue cell functions. More specifically, I study the cell types and functions considered to be relevant to understanding chemomechanics of neovascularization, wound healing and tumor metastasis.