Hunter Bennett is a Senior in the Department of Bioengineering. Upon arriving at the University of Washington in 2010, he was amazed by the innovative work being done across campus to create novel therapies for disease. Hunter’s passion for translating scientific knowledge into treatments led him to join the lab of Dr. Kim Woodrow in the Department of Bioengineering. The Woodrow Lab centers on developing novel biomaterials to prevent sexually transmitted diseases and empower women in 3rd world countries. Within the Woodrow Lab, Hunter investigates the potential of cell-seeded hydrogel systems to induce mucosal and systemic immunity to HIV. Hunter is also involved in a project investigating the molecular basis of dendritic cell movement in the vaginal mucosa. Hunter has also worked under Dr. Kent Hill in the Department of Microbiology, Immunology and Molecular Genetics at UCLA, where he worked to understand social signaling in African Trypanosomes. Through his studies and personal experience Hunter has developed an interest in the intersection of medicine and scientific research, and after graduation he hopes to follow this interest by pursuing an MD/PhD. Outside of the laboratory and classroom, Hunter enjoys running, lifting weights, and rooting for the Husky basketball and football teams.
Mentor: Kim Woodrow, Bioengineering
Project Title: Nanoporous Capsule for Sustained Delivery of Immunogenic HIV Virus Like Particles
Abstract: Despite decades of research, our best attempts at formulating a vaccine for the human immunodeficiency virus (HIV) have failed. Recent work in mucosal immunology and virology has highlighted the importance of the mucosal immune system in the successful infection of a host after mucosal exposure to HIV. A vaccine formulation that effectively induces humoral and cellular immune responses in the vaginal mucosa could clear local HIV populations before the virus is able to gain a foothold in the body. The proposed project will develop a novel vaginal mucosal HIV vaccine using therapeutic cell encapsulation. Briefly, a transgenic cell line producing HIV virus-like particles (VLPs) will be entrapped within a nanoporous polycaprolactone (PCL) capsule optimized to release VLPs. Release of the VLPs and viability of entrapped cells will be studied over long periods of time and controlled by an electrospun PCL membrane. Finally, the ability of the cell-based vaccine to interact with dendritic cells will be studied through the bone marrow dendritic cell uptake assay and the mixed lymphocyte reaction assay. This work would represent the first use of cell encapsulation technology to create a vaccine. If successful, this project could generate essential data that could be used to develop novel mucosal HIV vaccine for human testing.
Eager to pursue a growing curiosity in the mechanics of the heart, I was fortunate to join Dr. Murry’s team at the UW Medicine Department of Pathology. The lab’s focus on regenerative medicine has brought together a passionate group of researchers that are dedicated in developing stem-cell therapies for myocardial infarctions. I am thrilled with the opportunity to culture and differentiate stem cells into active cardiac tissues, and I still get a rush every time I look under the microscope and watch the cells beating.
To help strengthen the newly formed cardiomyocytes, I am currently engineering a device to simulate the mechanical environment of the heart. Improving the contractility of the cardiac tissue will bring tissue engineering closer in developing therapeutic patches to restore the functionality of a damaged heart. Despite the numerous challenges, it is invigorating to apply and integrate biochemistry with the principles of engineering to build and optimize the device.
Researching has been a transformative experience, encouraging me to question and explore the unknown. Being able to apply my education to the forefront of science has substantiated my undergraduate career, and has inspired me to pursue an MD/PhD in cardiology. As a future researcher and a cardiologist, I aim on helping those suffering from the aftermath of a heart attack return to the quality of life we all deserve.
Dr. Murry and his team have been amazing mentors and a tremendous support in helping me bring this ambitious project into a reality. I would like to wholeheartedly thank the Washington Research Foundation for its generous support and encouragement, allowing me to continue my research with energy and fervor.
Mentor: Charles Murry, Pathology
Project Title: Engineering high-performance cardiac tissue by simulating the mechanics of the heart
Abstract: Affecting millions of people globally, the WHO deems myocardial infarctions as the largest of cause of death worldwide. The heart’s weak regenerative capacity leads to scarring of infarcted tissue which reduces cardiac output and poses long-term health consequences. Tissue engineering is a promising outlook in restoring the structural integrity and contractile force of affected areas, where engineered constructs subjugated to mechanical stimuli have demonstrated similar characteristics to native cardiac tissue. To improve construct performance, this project investigates a novel concept that subjugates constructs to the complete mechanical profile experienced by native heart tissue. The device will contain two posts that vary in stiffness where constructs will attach. Upon contracting, constructs will face a resistance by the posts that will simulate the afterload stress against which the ventricular wall contracts to eject blood into the aorta. Constructs will then be stretched to simulate the preload stress that the wall tissue faces as the ventricles fill prior to ejection. By combining the afterload and preload schemes, constructs will experience the entire mechanical profile necessary for complete maturation. The goal is to produce cardiac tissue constructs with a contractile force, electrical conduction velocity and histology at par with native tissue. These tissues can then be employed clinically to replace infarcted areas and improve cardiac output along with the quality of life after a myocardial infarction.
Jen Choi is currently a senior in the Department of Bioengineering. Though pre-med focused, her motivation to study bioengineering and become involved in research was rooted in her interest in the development of new therapies and diagnostics for medical applications. Her dream is to develop these therapies and someday use them in patients. She began her research experience the summer before her freshman year in Miqin Zhang’s lab. In the Zhang group, she worked on superparamagnetic iron oxide nanoparticles for delivery of therapeutics to the central nervous system. After 1.5 years, she switched to Suzie Pun’s lab, where she is now working on her capstone project. In this project, she is developing multi-functional polymers for targeted delivery of genetic material to the central nervous system. Previously, she has also participated in the Amgen Scholars Program at UCSD where she helped make vaccines against drugs of abuse. Jen plans to pursue an MD/PhD. Outside of lab, she enjoys running, baking, and long walks on the beach.
Mentor: Suzie Pun, Bioengineering
Project Title: Guanidinylation and Tet1 Targeting Peptide Modification of Cationic Copolymers for Gene Delivery
Abstract: As our understanding of the genetic basis for the pathophysiology of many diseases has broadened, gene therapy, which is the delivery of genetic material into cells in order to supplement or alter defective genes, is being explored as a potential treatment option. Despite its promise, no gene therapies have been approved for clinical use due to the lack of safe and effective vectors. There are many obstacles that must be overcome in order to produce safe and efficient vectors. First, the vector-DNA complex must navigate through the extracellular environment and be uptaken into the target cell. Then, the genetic material must achieve endosomal escape, be released from the complex, and then translocate into the nucleus where it can be transcribed and translated into functional or therapeutic proteins. In the Pun Lab, we previously synthesized a block-statistical copolymer comprised of different hydrophilic and hydrophobic segments aimed at providing a plethora of functionalities to the formed polyplexes. Due to this polymer’s unique architecture, it exhibits transfection efficiencies higher than branched polyethyleneimine, the gold standard for nonviral gene delivery, but still fails to reach the same level of transfection efficiency as seen with viral vectors. In this project, two additional modifications will be made to the copolymer and a library of well-defined polyplexes with varying formulations and structures will be synthesized and evaluated in vitro and in vivo. These modifications, guanidinylation and conjugation of a targeting peptide, aim to increase uptake into cells through electrostatic interactions and increase localization to the target cell type. From these studies, the ideal method to incorporate both modifications into one system to improve transfection efficiency and the structure-function effects on transfection efficiency will be evaluated.
Molecular biology has always been my first love; the intrinsic complexity of biological systems is endlessly fascinating. That being said, it is this same complexity that raises issues when attempting to analyze and understand the mechanisms that underlie these systems. After transferring to the University of Washington, I began to become aware of the wealth of solutions that engineering had to offer for these problems. I joined Human Photonics Lab (HPL) in the summer of 2012 in order to explore optics, bioengineering, and translational research. Under the guidance of my mentors, Dr. Eric Seibel, Dr. Leonard Nelson, and PhD candidate Chenying Yang, I created a color-matched esophagus phantom for Scanning Fiber Endoscope (SFE). This first project convinced me that interfacing biology and engineering was the path to advancing clinical research. Currently, I am working on a project to characterize the expression patterns of biomarkers present on the surface of some malignant and pre-malignant esophageal cells. I will then develop a biomarker-linked test bed of fluorescent values that could later be used for point-of-care diagnosis of pre-cancerous lesions during SFE guided surveillance. After I graduate, I intend to pursue an MD/PhD (Bioengineering) with a focus on minimally invasive early cancer detection. I deeply appreciate the generous gift from the Washington Research Foundation; it will allow me to focus on my coursework and my research. Their generosity further inspires me to work hard so that I may one day return their support in kind to our community.
Mentor: Eric Seibel, Mechanical Engineering
Project Title: Development of a biomarker test bed for fluorescence-based diagnosis of esophageal adenocarcinoma
Abstract: Early diagnosis of esophageal adenocarcinoma (EAC) while in its pre-cancerous states is a crucial step in effective treatment. White light endoscopy combined with biopsy of suspicious tissue is the current gold standard for detection. Interpatient variability as well as interobserver variability can confound visual staging of disease progression, potentially leading to inaccurate diagnosis. Biopsy is an inherently invasive procedure that can lead to uncontrolled bleeding. In addition to this, localized biopsy sampling can lead to false negatives due to variable cancer location; the results do not establish a comprehensive assessment of the region in question. There is a need for the development of a comprehensive and minimally invasive surveillance technique to improve both the sensitivity and the specificity of diagnosis. An increase in genomic instability is often reflected by differential biomarker expression, interpretation of these expression patterns can contribute towards a more accurate diagnosis. Three biomarkers that have been shown to be strongly associated with EAC are AMACR, IMP3, and CYPA. The use of fluorescence dyes conjugated to molecular probes can be used to label these diagnostic biomarkers. The wide field, multimodal, ultra-thin, scanning fiber endoscope (SFE) is able to excite and image emissions from fluorescent dyes. The focus of this research is the development of a quantified, biomarker-linked, fluorescence-based disease staging test bed for EAC. The data taken from this study could be used develop SFE algorithms for minimally invasive, point-of-care fluorescence diagnostics during endoscopic examination of patients.
Jared Houghtaling joined the joint lab of Professors Paul Yager, Barry Lutz, and Elain Fu during his freshman year, and working in the lab has since opened the doors to biomedical research as a career. Now a senior In the Department of Bioengineering, Jared was drawn to innovating solutions that expand access to healthcare. His desire to pursue research on porous membrane-based diagnostics is largely motivated by the fact that many people in the developing world die from curable diseases because of a lack of appropriate testing. Accurate diagnostic tools can save countless lives and improve quality of living all over the globe. Alongside his mentor, Dr. Elain Fu, he has designed and patented a novel porous membrane-based valving method to further automate and sophisticate diagnostic assays. Jared is currently working on a novel displacement based assay, designed to detect small molecules, which would be used for food/water safety, rapid detection of the stress hormone cortisol, and drugs-of-abuse testing. He plans to carry on with his passion for biomedical research by pursuing a Ph.D. in bioengineering. Outside of the lab, Jared is an active UW Biomedical Engineering Society Officer, serving as the organization’s president this year. He is also an officer on the Global Health Undergraduate Leadership Committee, and coordinates various bioengineering and global health outreach events for undergraduates and local high school students. In his fleeting spare time, he enjoys cycling, playing the guitar, and spending time with friends and family.
Mentor: Elain Fu, Bioengineering
Project Title: Development of a Displacement Format, Porous Membrane-Based Diagnostic for Small Molecule Detection
Abstract: Porous membrane-based lateral flow assays have become very popular for the diagnosis of a wide range of conditions. Attributes of these assays vary drastically depending upon application. Most commercially available lateral flow tests (LFTs) employ a ‘sandwich’ format, where the target molecule is effectively sandwiched between a surface anchored antibody and a visibly labeled antibody. Because small molecules lack multiple epitopes (antibody binding sites), they cannot support the binding of two antibodies simultaneously, and thus cannot be detected using a sandwich format. Competition format assays offer a solution to this problem, allowing target analyte in the testing sample to compete for surface-anchored antibody binding sites with pre-bound, conjugated analyte. The subsequent displacement of conjugated analyte (loss of visible signal) is then correlated with concentration of analyte in the sample. However, competition assay techniques fall short in two key areas: they rely on a counterintuitive, inverted user read-out where a darker signal translates to lower concentration, and they lack the ability to chemically amplify signals. My work seeks to modify and improve current competition methods by capturing the displaced, conjugated analyte downstream using a complimentary protein binding pair (e.g. streptavidin and biotin). Captured analyte could then be labeled using gold-nanoparticle antibody conjugates or enzymatic colorimetric chemistries to produce a very sensitive positive signal. The ultimate goal is to develop a ‘displacement format’ assay in a porous membrane network that greatly improves the limit of detection for small molecules and short peptide sequences. Specific applications include: rapid detection of cortisol to diagnose post-traumatic stress disorder or Cushing’s disease, therapeutic monitoring of HIV, TB, and epilepsy biomarkers, and field-use testing for active drug components like Δ9 THC in marijuana. Such an assay would have tremendous utility at the point-of-care, and would provide an efficient and effective alternative to expensive lab-based testing.
Jeremy Housekeeper is a senior studying Chemistry and Biochemistry.
Jeremy Housekeeper began his research career during the summer following freshman year in the lab of Professor Christine K. Luscombe. As part of Professor Luscombe’s lab in Materials Science and Engineering, he is working on the development of next-generation materials and synthetic techniques for organic electronics applications.
His current project focuses on the synthesis of dithienothiophene (DTT) and other molecules through C-H activation. C-H activation is an emerging catalytic methodology that eschews the use of traditional organometallic-functionalized precursors. Through C-H activation, compounds can be synthesized in fewer steps and with significantly reduced environmental impact.
With support from the WRF Fellowship, Jeremy is looking to further develop C-H activation methodologies so that DTT and similarly complex compounds can be made both cheaply and easily.
Mentor: Christine Luscombe, Materials Science & Engineering
Project Title: Heterocycle Synthesis through a C-H Activation Cascade Reaction
Abstract: Until recently, little research has been done on C-S bond formation in transition-metal catalyzed transformations compared to other carbon-heteroatom bonds such as C-N, C-O, and C-P. As sulfur-based coupling partners (thiol and disulfide for example) tend to poison transition-metal catalysts, development of C-S bond formation has been slow. However, a recent nickel-catalyzed system shed new light on this difficult transformation. In this context, C-H functionalization is a sustainable and straightforward approach to sulfur-containing heteroaromatic production. C-H activation is a process whereby a carbon-hydrogen bond is cleaved, thereby allowing the exposed carbon atom to form new bonds. Thus, in order to expand the above research of C-S bond formation toward development of short synthesis for fused thiophene systems, focus was placed on a palladium catalyzed cascade-type reaction system. C-H activation reactions can and have been manipulated to work in a cascade-type fashion. By combining cascade-type methodology with the reduced environmental impact of C-H activation, these fused thiophenes can be synthesized cleanly and efficiently. The test substrates in this work are O,O-diethyl S-phenyl phosphorothioate and 4,4,5,5-tetramethyl-2-(thiophen-2-yl)-1,3,2-dioxaborolane. Both substrates were chosen because they contain sulfur, thereby aiding the C-H activation process. By effecting a C-H activation with a palladium catalyst at one of the ortho carbons of the phenyl ring with the boronic ester of the thiophene, the first C-C bond will be formed. In the time immediately after this first transformation, the now-changed palladium complex is able to insert into the S-P bond of the phenyl-based compound. This step sets up the second reaction, whereby the phosphorothioate directing group is cleaved along the S-P bond and the resulting thiol is coupled to a carbon atom to close the ring. This molecule is known as benzo[b]thieno[2,3-d]thiophene.
I am currently working with Professor Carlos Guestrin, a leading expert in machine learning. My first exposure to machine learning was in junior year, when I took a class from Professor Guestrin about big data. I quickly realized how valuable machine learning was becoming, with tech companies collecting massive amounts of data from which important insights could be extracted. I became extremely interested by the rigorous approach of machine learning to modeling and by the emphasis on utilizing the newest technological advances to solve questions about data. At the moment Professor Guestrin and I are working on the improvement of recommendation engines–algorithms that detect user preferences and make product suggestions in services such as blog or video websites. The support from the WRF Fellowship will help us move forward with development and implementation of new ideas. After graduation, I hope to enter a PhD program in machine learning or join industry as a machine learning scientist.
Mentor: Carlos Guestrin, Computer Science & Engineering
Project Title: Community Detection in Social Networks
Abstract: A/B testing is a standard approach for evaluating the effect of online experiments; the goal is to estimate the “average treatment effect” of a new feature or condition by exposing a sample of the overall population to it. A drawback with A/B testing is that it is poorly suited for experiments involving social interference, when the treatment of individuals spills over to neighboring individuals in a community along an underlying social network. In this work, social networks are modeled as graphs, and communities are represented as clusters. We propose a novel methodology using graph clustering to analyze average treatment effects under social interference. We examine theoretical properties of this methodology as well as its empirical performance.
Ever since I was little, I was always attracted to one of the greatest marvels of this universe: life itself. My interest in bioengineering was piqued for the first time, however, after witnessing how medical devices and implantable materials became a reality to help patients. After witnessing these medical miracles, I knew that I wanted to conduct research in regenerative medicine to improve the quality of life of patients. I entered the University of Washington with the intent of pursuing bioengineering research as my primary motivation. Since the summer of my freshman year, I have been conducting research in Dr. Deok-Ho Kim’s lab. His research is focused on how engineered microenvironments can direct cell function and regeneration. Currently, I am investigating how specially designed microenvironments of varying topographies, rigidities, and chemical cues can direct stem cell differentiation into cell lineages found in the heart. My growth would not have been possible without the incredible support and mentorship I have had in Dr. Kim’s lab.
After I complete my undergraduate degree, I intend to pursue a PhD in bioengineering. I am fascinated by the incredible potential of regenerative medicine and would like to pursue a professional career in this area. In addition, I would like to sincerely thank the Washington Research Foundation for their generosity and support, which will allow me to continue my research and bring me one step closer to my professional goals.
Mentor: Deok-Ho Kim, Bioengineering
Project Title: Engineering combinatorial microenvironments for human cardiovascular cell fate determination
Abstract: Myocardial infarction remains the leading cause of death and disability in developed nations. While current therapeutics are able to slow the progression of heart disease, there are no viable treatment options to repair damaged myocardium. As such, cardiac stem cell therapy has received much attention for its promise to repair damaged heart tissue. However, there currently is no ideal stem cell source for cardiac stem cell therapy. Cardiovascular progenitors (CVPs) are stem cells that can differentiate into cardiomyocytes, endothelial cells, and vascular smooth muscle cells, but CVP cell fate determination is not well understood. It is well known that stem cells respond to the physical, geometric, and chemical cues provided by the microenvironment. Herein, we report the development of a platform that allows specific design and control over the in vitro stem cell microenvironment. Polyurethane acrylate (PUA) is a synthetic polymer with tunable rigidity and can be used to form nanopatterned substrates through the use of capillary-force lithography (CFL). Bifunctional PUA-binding peptides that contain the RGD peptide sequence are used for presentation of cell adhesion sites. We report precise control over the physical rigidity, nanotopographical dimensions, and RGD peptide presentation. We anticipate that our platform will be able determine the optimal conditions required for directing CVP cell fate. Thus, by determining the conditions responsible for CVP cell fate determination, CVPs could be a viable cell source for cardiac stem cell therapies.
As an undergraduate student I have had many scientific interests – I have worked in fields ranging from physiology to biochemistry to synthetic chemistry before reaching my current position as a computational physicist. In my Sophomore year I joined the research group of professor David Masiello; for two years we have worked together to understand how metal nanoparticles absorb, transport, and scatter electromagnetic energy. We have discovered fundamental symmetries behind the selection rules that govern how different electromagnetic stimuli interact with nanoparticles, and have designed an intuitive theoretical model that explains the electromagnetic response of metal nanoparticles. I am currently working on extending this model to better understand recently observed large magnetic responses of cyclic nanoparticle systems. I hope that as a result of my work I will be able to design nanoparticle systems with arbitrary magnetic responses, opening new doors in rapidly-growing fields such as single-molecule sensing and electromagnetic cloaking.
Upon graduating I hope to pursue theoretical physics as a graduate student. I greatly appreciate the tremendous time and energy that my mentors have invested in my growth as a scientist, and I aspire to follow in their footsteps and pursue an academic career as well. The Washington Research Foundation Fellowship has given me the financial freedom to completely devote myself to research, allowing me to spend most of my senior year working on the frontiers of nano-optics.
Mentors: David Masiello, Chemistry
Project Title: A Study of the Excitation and Decay Pathways of Plasmonic Resonances
Abstract: Collective oscillations of conduction electrons in metal nanoparticles, known as localized surface plasmon resonances (LSPRs), have been the source of much scientific study over the last decade due to their immediate and significant applications in chemical catalysis, drug delivery, and cancer reduction therapy. In previous studies we have thoroughly analyzed the radiative decay pathways of both light- and electron beam- induced LSPRs and have implemented a computational model to simulate LSPR generation and decay. The purpose of this work is to study the nonradiative decay pathways of LSPRs, specifically heat, which govern many of the aforementioned applications. We propose to simulate the heating of nanoparticles by computationally solving the driven heat equation under the discrete (thermal) dipole approximation. Much previous literature has solved the driven heat equation using approaches such as the finite elements method and boundary value method, but these are computationally inefficient for large systems. This work proposes an approach that is analogous to our simulation of radiative LSPR decay and eliminates the need to discretize the medium and thus vastly reduces computational time. Upon successful implementation of a predictive computational model we will be able to study the relationships between radiative and nonradiative decay pathways of LSPRs.
My passion for the biological sciences started after taking an introductory biology course my freshman year of high school. What grabbed my attention then—and is still riveting to me now—is the elegance of cellular systems in seemingly simplistic microscopic organisms. I carried this fascination with me to UW and immersed myself in biological research. Yet what was inescapable was the realization of the complex interplay of biology, politics, and socioeconomic factors that resulted in a disproportionate burden of disease on those living in the margins of society. This acknowledgement catalyzed a critical reflection of my intentions. I became interested in how the human body utilizes internal factors to fight diseases that affect those in the margins of society.
I joined the Overbaugh Lab at the Fred Hutchinson Cancer Research Center in the summer of 2012. The lab studies both the viral and host factors that impact the transmission and pathogenesis of HIV-1. My project looks to map the specific epitopes of the HIV envelope that confer sensitivity to a broadly neutralizing monoclonal antibody, in order to provide insight into how to develop a vaccine that would elicit similar antibodies. I receive wonderful guidance from my graduate mentor Leslie Goo, my faculty mentor Julie Overbaugh, and the Overbaugh Lab. Their mentorship has strengthened my confidence in my ability to carry out independent biological investigations and prepared me for graduate studies. I hope to eventually work as a medical scientist in a position that will allow me to work on front lines of combating diseases that have caused hardships for humans globally.
I am deeply thankful of the Washington Research Foundation for their support in my research and education.
Mentors: Julie Overbaugh, Microbiology; Leslie Goo, Global Health
Project Title: Investigating Epitopes of Viral Sensitivity to Broadly Neutralizing Antibodies in HIV-1
Abstract: Since the beginning of the AIDS epidemic, nearly 30 million people have died of HIV-related causes. Developing a vaccine for HIV-1 will greatly reduce the incidence rate of infection and eventually eliminate the disease from the population. Immunization studies in nonhuman primate models have provided proof of concept for neutralizing antibodies to protect against initial infection if they were elicited by vaccination and were thus present at the time of virus exposure. The key challenge in designing effective neutralizing antibody-based vaccines is to elicit neutralizing antibodies that are broad and potent in order to recognize and effectively counteract diverse circulating HIV-1 strains. PGT128- is a HIV-1 monoclonal antibody that has been isolated and identified as having a broad neutralizing activity that would be desirable for a vaccine to elicit. My project looks to identify and map regions of the viral envelope important for recognition by PGT128 in hopes of understanding how to elicit broadly neutralizing antibodies like PGT128. My project also looks to determine if the regions that confer sensitivity to PGT128 are also responsible for escape from autologous antibodies. Our lab found that longitudinal viruses isolated from a HIV-1 infected patient, QA255, display increasing sensitivity to PGT128 across 560 days post infection. Using overlap PCR, we will create chimeras of the HIV env gene by exchanging different portions of the DNA from different time points. We will then test these chimeras in neutralization assays to determine the neutralization profiles against PGT128 and autologous antibodies. By creating a series of chimeras we can pinpoint to specific sequences on the envelope gene that confer sensitivity to PGT128. Preliminary data show amino acids in the V1-C3 region of HIV env to contain epitopes of sensitivity to PGT128. Further steps include fine-mapping this region and testing these chimeras against autologous antibodies.