David A. Weitz, PI
weitz@deas.harvard.edu
Curriculum Vitae
Harvard University
Gordon Mckay Laboratory of Applied Science
9 Oxford Street
Cambridge MA 02138

Laboratory Interests:

Our group studies soft materials - pastes, gels, and polymer networks. Under some conditions these materials flow like liquids while under other conditions they remain rigid like solids. We study the microstructural properties that give rise to these macroscopic mechanical behaviors. How are the individual structural elements interacting to allow deformation and flow of these materials? What determines the stiffness of the materials when they are solid-like? Biological materials such as the cytoskeletal network inside cells and the extracellular matrix that cells crawl through are soft materials and we can ask these kinds of questions to try to understand the mechanics of biological processes such as tumor growth and metastasis. For example, as tumor glioblastoma cells invade the surrounding matrix the cells apply forces and deform the matrix. A cell branch invading an initially isotropic collagen gel will remodel the gel and align the collagen fibers as shown in figure 1. We'd like to quantify this mechanical interaction to learn how the matrix structure and resulting deformation affects the growth and invasion patterns of the tumor cells.

Involved in this effort in our group are:

Cliff Brangwynne, graduate student, brangwyn@fas.harvard.edu
Emma Filippidi, undergradate, filippid@fas.harvard.edu
Laura Kaufman, postdoc, lkaufman@fas.harvard.edu
Karen Kasza, graduate student, kasza@fas.harvard.edu

Relevant publications:

V.D. Gordon, M.T. Valentine, M.L. Gardel, D. Andor-Ando, S. Dennison, A.A. Bogdanov, D.A. Weitz, and T.S. Deisboeck. Measuring the mechanical stress induced by an expanding multicellular tumor system: A case study Experimental Cell Research 289 (2003) 58-66

Figure 1. Tumor cells remodelling a gel of Collagen I.