Penn Bioengineering Senior Discusses Remote Research Experience

Yi-An Hsieh (BE 2023)

Yi-An Hsieh, a fourth year Bioengineering student from Anaheim, California, worked remotely this summer on a team that spanned three labs, including the Kamoun Lab at the Hospital of the University of Pennsylvania. Hsieh credits her research on kidney graft failure with enriching her scientific skill set, exposing her to machine learning and real-time interaction with genetic datasets. In a guest post for the Career Services Blog, Hseih writes about her remote summer internship experience. “It showed me that this type of research energy that could not be dampened despite the distance,” she writes.

Read “Exploring How Amino Acid Polymorphisms Affect Graft Survival” in the Career Services Blog.

Noordergraaf and Blair Student Scholars Share Their Summer 2022 Research

Each year, the the Department of Bioengineering seeks exceptional candidates to conduct summer research in bioengineering with the support of two scholarships: the Abraham Noordergraaf Student Summer Bioengineering Research Fund and the Blair Undergraduate Research Fund in the Department of Bioengineering. These scholarships provide a living stipend for students to conduct research on campus in a Penn research lab under the mentorship of a faculty member. The Abraham Noordergraaf Student Summer Bioengineering Research Fund provides financial support for undergraduate or graduate summer research opportunities in bioengineering with a preference for study in the area of cardiovascular systems. Dr. Noordergraaf, who died in 2014, was a founding member and first chair of Penn Bioengineering. The Blair Undergraduate Research Fund in the Department of Bioengineering supports three to five undergraduate research scholars each year with the support of Dr. James C. Blair II. After a competitive round of proposals, the following six scholars were chosen for the Summer 2022 semester. Keep reading below for the research abstracts and bios of the awardees.

The Blair Undergraduate Research Fund in the Department of Bioengineering (Blair Scholars)

Ella Atsavapranee

Student: Ella Atsavapranee (BE Class of 2023)

PI: Michael J. Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation, Bioengineering

“Lipid nanoparticle-mediated delivery of RAS protease to inhibit cancer cell growth”

Mutations in RAS, a family of proteins found in all human cells, drive a third of cancers, including many pancreatic, colorectal, and lung cancers. However, there are still no therapies that can effectively prevent RAS from causing tumor growth. Recently, a protease was engineered to specifically degrade active RAS, offering a promising new tool for treating these cancers. However, many protein-based therapies still cannot be effectively delivered to patients. Lipid nanoparticles (LNPs), which were used in the Pfizer-BioNTech and Moderna COVID-19 vaccines, have emerged as a promising platform for safe and effective delivery of both nucleic acids and proteins. We formulated a library of LNPs using different cationic lipids. We characterized the LNPs by size, charge, and pKa, and tested their ability to deliver fluorescently labeled protease. The LNPs were able to encapsulate and deliver a RAS protease, successfully reducing proliferation of colon cancer cells.

Ella is a senior from Maryland studying bioengineering and chemistry. She works in Dr. Michael Mitchell’s lab, developing lipid nanoparticles to deliver proteins that reduce cancer cell proliferation. She has also conducted research on early-stage cancer detection and therapy monitoring (at Stanford University) and drug delivery across the blood-brain barrier for neurodegenerative diseases (at University of Maryland). She is passionate about translational research, science communication, and promoting diversity in STEM.

Chiadika Eleh

Student: Chiadika Eleh (BE and CIS Class of 2024)

PI: Eric J. Brown, Associate Professor of Cancer Biology, Perelman School of Medicine

“Investigating Viability in ATR and WEE1 Inhibitor Treated Ovarian Cancer Cells”

High-grade serous ovarian cancers (HGSOCs) are an aggressive subtype of ovarian cancer, accounting for up to 80% of all ovarian cancer-related deaths. More than half of HGSOCs are homologous recombination deficient; thus, they lack a favorable response when treated with common chemotherapeutic trials. Therefore, new treatment strategies must be developed to increase the life expectancy and quality of life of HGSOC patients. To address the lack of effective treatment options, the Brown Lab is interested in combining ATR and WEE1 inhibition (ATRi/WEE1i) to target HGSOC cells. It has previously been shown that low-dose ATRi/WEE1i is an effective treatment strategy for CCNE1-amplified ovarian cancer-derived PDX tumors (Xu et al., 2021, Cell Reports Medicine). Therefore, the next step is to characterize the HGSOC-specific response to ATRi/WEE1i treatment. This project aims to characterize the viability phenotype of ovarian cancer (OVCAR3) cells in the presence of ATRi/WEE1i in both single and combination treatments. With further research, Eleh hopes to prove the hypothesis low-dose combination ATRi/WEE1i treatment will result in the synergistic loss of viability in OVCAR3 cells. This goal will be achieved through the treatment of OVCAR3 cells with ranging doses of ATRi and Wee1i over 24 and 48 hour time intervals. We hope that this data will help set a treatment baseline that can be used for all OVCAR30-based viability experiments in the future.

Chiadika Eleh is a Bioengineering and Computer Science junior and a member of Penn Engineering’s Rachleff Scholar program. As a Blair Scholar, she worked in Dr. Eric Brown’s cancer biology lab, where she studied cell cycle checkpoint inhibitors as a form of cancer treatment.

Gloria Lee

Student: Gloria Lee (BE and PHYS Class of 2023)

PI: Yi Fan, Associate Professor of Radiation Oncology, Perelman School of Medicine, and member of the Penn Bioengineering Graduate Group

“Tbc1d2b regulates vascular formation during development and tissue repair after ischemia”

The mechanisms behind endothelial cells forming blood vessels remains unknown. We have identified Tbc1d2b as a protein that is integral to the regulation of vascular formation. In order to investigate the role of Tbc1d2b in tubule formation, fibrin gel bead assays will be conducted to evaluate how the presence of Tbc1d2b is required for angiogenesis. Fibrin gel bead assays simulate the extracellular matrix environment to support the in vitro development of vessels from human umbilical vein endothelial cells (HUVEC) coated on cytodex beads. In order to confirm the success of angiogenesis, immunostaining for Phalloidin and CD31 will be conducted. After confirmation that fibrin gel bead assays can produce in vitro tubules, sgRNA CRISPR knockout of Tbc1d2b will be performed on HUVEC cells which will then be used to conduct more fibrin gel bead assays. We hypothesize that HUVEC with the Tbc1d2b knockout phenotype will be unable to form tubules while wild type HUVEC will be able to.

Gloria Lee is a rising senior studying Bioengineering and Physics in the VIPER program from Denver, Colorado. Her research in Dr. Yi Fan’s lab focuses on the role that proteins play in cardiovascular tubule formation.

Abraham Noordergraaf Student Summer Bioengineering Research Fund (Noordergraaf Fellows)

Gary Lin

Student: Gary Lin (Master’s in MEAM Class of 2023)

PI: Michelle J. Johnson, Associate Professor in Physical Medicine and Rehabilitation, Perelman School of Medicine, and in Bioengineering

“Development and Integration of Dynamically Modulating Control Systems in the Rehabilitation Using Community-Based Affordable Robotic Exercise System (Rehab CARES)”

As the number of stroke patients requiring rehabilitative care continues to increase, strain is being put onto the US health infrastructure which already has a shortage of rehabilitation practitioners. To help alleviate this pressure, a cost-effective robotic rehabilitative platform was developed to increase access to rehabilitative care. The haptic TheraDrive, a one-degree of freedom actuated hand crank that can apply assistive and resistive forces, was modified to train pronation and supination at the elbow and pinching of the fingers in addition to flexion and extension of the elbow and shoulder. Two controllers were created including an open-loop force controller and a closed-loop proportional-integral (PI) with adaptive control gains based on subject performance in therapy-game tasks as well as galvanic skin response. Stroke subjects (n=11) with a range of cognitive and motor impairment completed 4 therapy games in both adaptive and non-adaptive versions of the controllers (n=8) while measuring force applied on the TheraDrive handle. Resulting normalized average power versus Upper Extremity Fugl-Meyer (UE-FM) and Montreal Cognitive Assessment (MoCA) correlation analyses showed that power was strongly correlated with UE-FM in 2 of the conditions and moderately correlated with the other 6 while MoCA was moderate correlated to 2 of the conditions and weakly correlated to the rest. Mann-Whitney U-tests between adaptive and non-adaptive versions of each therapy game showed no significant differences with regards to power between controller types (p<0.05).

Gary is a master’s student in the School of Engineering studying Mechanical Engineering and Applied Mechanics with a concentration in Robotic and Mechatronic systems. His research primarily focuses on developing affordable rehabilitation robotics for use in assessment and game-based therapies post neural injury. Many of his interests revolve around the design of mechatronic systems and the algorithms used to control them for use in healthcare spaces.

Priya Shah

Student: Priya Shah (BE Class of 2024)

PI: Alex J. Hughes, Assistant Professor in Bioengineering

“Optogenetic Control of Developing Kidney Cells for Future Treatment of End-Stage Renal Disease”

This project sought to build from prior research in the Hughes Lab on the geometric and mechanical consequences of kidney form on cell and tissue-scale function. While the developmental trajectory of the kidney is well understood, little is currently known about many factors affecting nephron progenitor differentiation rate. Insufficient differentiation of nephron progenitor cells during kidney formation can result in lower nephron number and glomerular density, which is a risk factor for progression to end-stage renal disease later in life. Prior studies indicated that the amount of nephron differentiation – and thus function of the adult kidney – is correlated to the packing of ureteric tubule tips present at the surface of the kidney. Building off of research conducted in the Bugaj Lab, we found that inserting an optogenetic construct into the genome of human embryonic kidney (HEK) cells allowed us to manipulate the contraction of those cells through exposing them to blue light. Manipulating the contraction of the cells allows for the manipulation of the packing of ureteric tubule tips at the kidney surface. We used a lentiviral vector to transduce HEK293 cells with the optogenetic construct and witnessed visible contraction of the cells when they were exposed to blue light. Future work will include using CRISPR-Cas9 to introduce the optogenetic construct into IPS cells.

Priya is a junior studying bioengineering and had the opportunity to work on manipulating developing kidney cells using an optogenetic construct in the Hughes Lab this summer. She is thrilled to continue this research throughout the coming school year. Outside of the lab, Priya is involved with the PENNaach dance team and the Society of Women Engineers, as well as other mentorship roles.

Cosette Tomita

Student: Cosette Tomita (Master’s in MEAM Class of 2023)

PI: Mark Anthony Sellmyer, Assistant Professor, Radiology, Perelman School of Medicine and member of the Penn Bioengineering Graduate Group

“Expression and Characterization of an Anti-Aβ42 scFv”

Background: Amyloid Beta (Aβ42) fibrils contribute to the pathology of Alzheimer’s Disease. Numerous monoclonal antibodies have been developed against Aβ42. In this study we have designed and expressed a short chain variable fragment specific to Aβ42 (Anti-Aβ42 scFv). To characterize our anti-Aβ42 scFv we have performed structural analysis using transmission electron microscopy (TEM) and binding kinetics using microscale thermophoresis (MST) compared to commercially available antibodies 6E10, Aducanumab, and an IgG isotype control. The goal of this study is to determine if labeling densities and binding constants for Aducanumab and anti-Aβ42 scFv are not significantly different.

Method: To characterize Aβ42 fibril associated antibodies we used negative stain TEM. Aβ42 fibrils were stained on a glow discharged copper grid, and incubated with gold conjugated anti-Aβ42 scFv, 6E10—which binds all Aβ species, aducanumab, or IgG isotype control. Labeling densities were calculated as the number of fibril-associated gold particles per 1 μm2 for each image. Next, we used microscale thermophoresis determine the binding kinetics. Antibodies or anti-Aβ42 scFv were labeled with Alexa Fluor-647 and unlabeled Aβ42 was titrated in a serial dilution over 16 capillaries. The average fluorescence intensity was plotted against the antibody or scFv concentration and the curves were analyzed using the GraphPad Prism software to calculate the dissociation constant (KD) values.

Results: We found a significant difference, tested with a one-way ANOVA (P <0.0001), in gold particle associated Aβ fibrils per 1 μm2 between anti-Aβ42 scFv, 6E10, aducanumab, and IgG isotype control. Further analysis of aducanumab and 6CO3 with unpaired student t-test indicates significant differences in fibril associated gold particles between aducanumab vs. 6E10 (P=0.0003), Aducanumab vs. Isotype control (P <0.0001), anti-Aβ42 scFv vs 6E10 (p=0.0072), and anti-Aβ42 scFv vs Isotype Control (P=0.0029) with no significant difference in labeling densities between Aducanumab and anti-Aβ42 scFv. The expected KD values from MST were 1.8μM for Aducanumab and anti-Aβ42 scFv, 10.3nM for 6E10 and no expected binding for the isotype control. The experimental KD values for anti-Aβ42 scFv and 6E10 are 0.1132μM and 1.467μM respectively. The KD value for Isotype control was undetermined, as expected, however, the KD for Aducanumab was undetermined due to suboptimal assay conditions. Due to confounding variables in the experimental set up such as the use of Aβ1-16 compared to Aβ42 and the use of different fluorophores—5-TAMRA, Alexa Fluor 647 or FITC— the experimental KD values were off by several orders of magnitude.

Conclusion: We have illustrated similar labeling densities between Aducanumab and our anti-Aβ42 scFv. In the future, we will further optimize the MST assay conditions and compare the KD values obtained by MST with other techniques such as surface plasma resonance.

Cosette was born and raised in Chicago land area. Go Sox! She attended University of Missouri where she majored in Chemistry and Biology. She synthesized sigma-2 radiotracers and developed advanced skills in biochemical techniques in Dr. Susan Lever’s lab.  After graduation, she moved to NJ to work at Lantheus, a radiopharmaceutical company. She missed academia and the independence of program and project development, so she came to work at the Penn Cyclotron facility before entering the Bioengineering master’s program.

2021 CAREER Award recipient: Alex Hughes, Assistant Professor in Bioengineering

by Melissa Pappas

Alex Hughes (illustration by Melissa Pappas)

The National Science Foundation’s CAREER Award is given to early-career researchers in order to kickstart their careers in innovative and pivotal research while giving back to the community in the form of outreach and education. Alex Hughes, Assistant Professor in Bioengineering and in Cell and Developmental Biology, is among the Penn Engineering faculty members who have received the CAREER Award this year.

Hughes plans to use the funds to develop a human kidney model to better understand how the development of cells and tissues influences congenital diseases of the kidney and urinary tract.

The model, known as an “organoid,” is a lab-grown piece of human kidney tissue on the scale of millimeters to centimeters, grown from cultured human cells.

“We want to create a human organoid structure that has nephrons, the filters of the kidney, that are properly ‘plumbed’ or connected to the ureteric epithelium, the tubules that direct urine towards the bladder,” says Hughes. “To achieve that, we have to first understand how to guide the formation of the ureteric tubule networks, and then stimulate early nephrons to fuse with those networks. In the end, the structures will look like ‘kidney subunits’ that could potentially be injected and fused to existing kidneys.”

The field of bioengineering has touched on questions similar to those posed by Hughes, focusing on drug testing and disease treatment. Some of these questions can be answered with the “organ-on-a-chip” approach, while others need an even more realistic model of the organ. The fundamentals of kidney development and questions such as “how does the development of nephrons affect congenital kidney and urinary tract anomalies?” require an organoid in an environment as similar to the human body as possible.

“We decided to start with the kidney for a few reasons,” says Hughes. “First, because its development is a beautiful process; the tubule growth is similar to that of a tree, splitting into branches. It’s a complex yet understudied organ that hosts incredibly common developmental defects.

“Second,” he says, “the question of how things form and develop in the kidney has major medical implications, and we cannot answer that with the ‘organ-on-a-chip’ approach. We need to create a model that mimics the chemical and mechanical properties of the kidney to watch these tissues develop.”

The fundamental development of the kidney can also answer other questions related to efficiency and the evolution of this biological filtration system.

“We have the tendency to believe that systems in the human body are the most evolved and thus the most efficient, but that is not necessarily true,” says Hughes. “If we can better understand the development of a system, such as the kidney, then we may be able to make the system better.”

Hughes’ kidney research will lay the foundation for broader goals within regenerative medicine and organ transplantation.

Read the full story in Penn Engineering Today.

Alex Hughes Receives the First MIRA Award of Penn SEAS

by Sophie Burkholder

Alex Hughes, Ph.D.

We would like to congratulate Assistant Professor in Bioengineering Alex Hughes, Ph.D., on receiving the Maximizing Investigators’ Research Award (MIRA) from the National Institutes of Health (NIH), which funds investigators to create flexible and forward-thinking research programs. Hughes is the first recipient of this award in Penn’s School of Engineering and Applied Science, marking a major accomplishment for him and his lab.

The award recognizes Hughes’ efforts to create new  tools used for tissue engineering, in particular by fusing concepts from developmental biology into tissue construction efforts. Hughes believes this approach will have impacts on fundamental understanding human disease, leading to new strategies to combat them. Hughes and his lab specifically focus on kidney disease. As Hughes says, “defects in the kidney and urinary tract account for up to a third of all birth defects.” Furthermore, because kidney development involves many different kinds of cell interactions, there’s a gap in understanding exactly how these defects occur.

Unlike other grants that focus on funding projects, the MIRA prioritizes the people behind the research, giving them funding as a sign of faith in the future work they’ll choose to do. “The MIRA has allowed us significant leeway to integrate several complementary approaches here,” Hughes says. Because of this flexibility, Hughes and his lab thinks it will allow them to reach for more innovative and risky approaches in their research, in the hopes that this will lead to a better understanding of kidney defects and modes of treatment for them.