Macosko Lab


Jed Macosko, Assistant Professor of Physics

Prof. Jed Macosko holds a B.S. from MIT and a Ph.D. from UC Berkeley. He was a postdoctoral researcher under Prof. Carlos Bustamante, and also under Prof. David Keller. The Macosko-Holzwarth lab is currently focused on the mechanical properties of cancer. Prof. Macosko first collaborated with Dr. George Holzwarth in 2004 to explore how multiple motor proteins pull a single cargo in living cells. Prof. Macosko also partners with the lab of Profs. Keith Bonin and Martin Guthold to develop a new drug discovery platform and with Dr. A. Daniel Johnson of the Department of Biology to develop new teaching technologies.

George Holzwarth, Research Professor

George Holzwarth is a Research Professor in the Wake Forest Physics Department. Our lab is interested in 3 problems: 1) the load-dependence of molecular motors, especially kinesin-1, and how multiple motors cooperate or interfere with one another; 2) how cells move along two-dimensional surfaces; 3) how cells penetrate gels, layers of cells, and the extracellular matrix.. Using video microscopy of gfp-labelled peroxisomes, we record the thermally driven motions of vesicles in live cells. From the vesicle tracks, we extract intracellular mechanical properties such as the elastic and viscous shear moduli of the cytoplasm. These moduli are likely to play a role in the dynamics of cell deformation. A long-standing difficulty afflicting the analysis of particle tracks is their start-stop nature. We’ve been developing a hidden Markov, variational Bayes, Gaussian mixture model to objectively separate tracks into 2 or more states characterized by whether the vesicle is motor-driven or obeys the laws of diffusion.

Amanda Smelser, PhD Candidate

Amanda is a PhD candidate in biochemistry and a National Science Foundation Graduate Research Fellow. She is interested in the mechanical properties of breast cancer cells and the influence of microenvironment stiffness gradients on their invasive potential. To determine the viscoelastic properties of normal and cancerous mammary epithelial cells, she tracked peroxisome motion in motor-inhibited and ATP-depleted cells. She is now developing 3D photoactivatable collagen environments with stiffness gradients for determining if normal and cancerous breast cells experience durotactic migration and localize to regions of specific stiffness. Amanda is also a fiddler in a bluegrass band from Walkertown, NC called The Grassifieds. (Shameless promo here:

Scott Smyre, Undergraduate Student

I am a junior biophysics major from Salisbury, North Carolina. I am also pre-med with the ultimate goal of becoming a biomedical engineer. I am the trumpet visual section leader and library coordinator for The Spirit of the Old Gold and Black. I am a brother of Kappa Kappa Psi Spring '13. I am helping with the process of re-chartering MAPS (Minority Association of Pre-Medical Students) on our campus. In the lab I worked with the initial goal of gelling collagen by UV radiation and looking further we hope to be able to inject cells into these collagen gels. Upon graduating Wake Forest I plan to go to medical school.

Adam O'Dell, Undergraduate Student

I am a Junior Biophysics major with a Mathematics minor and I am from Greensboro, North Carolina. Outside of the lab, I am the captain for my intramural soccer team. I am also heavily involved in the campus ministry group, Presby. After graduating from Wake Forest, I plan to go to graduate school to get a Masters in Biomedical Engineering. In the lab, I have worked on a few different projects. I have used Brownian motion and a tracking software to compute the viscoelastic modulus for cells that were inhibited by Blebbsitatin. Most recently in collaboration, I have worked on creating a collagen gel with a stiffness gradient. I plan to track cells moving over this stiffness gradient.

Victoria Gee, Undergraduate Student

I am a senior Biophysics major with a minor in Mathematics from Long Island, New York. I am heavily involved with two organizations on campus, Wake Radio and Gay-Straight Student Alliance, as well as a national member of Phi Mu Fraternity. In the lab I am currently working on improving our method of particle tracking to analyze the viscoelastic modulus for collagen gels. My goal is to use this method to characterize gels with an increasing stiffness gradient in which we will observe the movements of cancer cells. After graduating from Wake Forest I am interested in pursuing a Masters degree in Biomedical Engineering.

Manuel Gomez, Undergraduate Student

I am a sophomore Biology major with a Chemistry minor from Matthews, North Carolina. I am on a pre-med track with the aspiration of becoming a surgeon. In the lab, I am working on making collagen gels with a stiffness gradient and measuring them with an Atomic Force Microscope to get the Young's Modulus. Eventually, I will grow cells in these gels and track their migration patterns. After graduating from Wake Forest, I plan on going to medical school and obtain an MD.

Previous Members

Lawson McDonald '15

Tim Kreutzfeldt '14

Hillary McDonald '12

Matthew Martin '12