Tirrell Group

John Barrett, Ph.D.

John Barrett received his BS in biomedical engineering with a concentration in nanotechnology from Boston University in Spring 2013. He is working toward his PhD in biophysical sciences at the University of Chicago under the dual mentorship of Professor Matt Tirrell and Professor Joel Collier. As an undergraduate, John worked with Professor Hatice Altug to develop a multiplexing plasmonic biosensor integrated with a microfluidic device to quickly and cheaply detect the adsorption of proteins and viruses in a label-free manner. His current research aims to study and characterize a potential peptide amphiphile micelle vaccine against Group A Streptococcus. His research interests broadly include biomaterials, synthetic vaccines, immunoengineering, and drug development.

Peptide vaccines have the advantage of providing only the necessary epitopes to induce an immunogenic response. Alone, however, they can be very weak immunogens. The group's solution is to deliver the epitope as part of a peptide amphiphile (PA) micelle system. This system creates a high local concentration of peptide, induces peptide secondary structure, and allows for modularity of micelle parts by inserting multiple amphiphiles or adjuvants (non-specific immuno-stimulants). Most of John's research will focus on developing a vaccine against Streptococcus pyogenes, which is the causative agent of Group A Streptococcal (GAS) infections including Necrotizing Fascitis. The PA and adjuvant mixed PA micelles have been shown to induce a high antibody titer. However, the method of immunogenicity has yet to be worked out. Characterizing the immune response will finally develop the full story for this vaccine. Additionally, John will be investigating alternate GAS vaccine candidates that will target and disrupt streptococcal quorum sensing (bacterial cell-cell communication) pathways in collaboration with the Federle Lab at the University of Illinois at Chicago. He proposes that these vaccines will help develop antibodies that interfere with pheromone production and detection.

Gadolinium-Functionalized Peptide Amphiphile Micelles for Multimodal Imaging of Atherosclerotic Lesi

S. P. Yoo, F. Pineda, J. C. Barrett, C. Poon, M. Tirrell, E. J. Chung. Gadolinium-Functionalized Peptide Amphiphile Micelles for Multimodal Imaging of Atherosclerotic Lesi. ACS Omega. 2016. Vol. 1, Pg. 996.

Modular Peptide Amphiphile Micelles Improving an Antibody-Mediated Immune Response to Group A

J. C. Barrett, B. D. Ulery, A. Trent, S. Liang, N. A. David, and M. Tirrell. Modular Peptide Amphiphile Micelles Improving an Antibody-Mediated Immune Response to Group A. ACS Biomaterials Science & Engineering. 2016.

Self-assembling peptide-based building blocks in medical applications

H. Acar, S. Srivastava, E. J. Chung, M. R. Schnorenberg, J. C. Barrett, J. L. LaBelle, M. Tirrell. Self-assembling peptide-based building blocks in medical applications. Advanced Drug Delivery Reviews. 2016.

Peptide Amphiphile Micelles Self-Adjuvant Group A Streptococcal Vaccination

A. Trent, B. Ulery, M. Black, J. Barrett, S. Liang, Y. Kostenko, N. David, and M. Tirrell. Peptide Amphiphile Micelles Self-Adjuvant Group A Streptococcal Vaccination. AAPS Journal. 2015. Vol. 17, Pg. 380-388.