Shelby Bess and Caroline Spainhour are undergraduates studying biomedical engineering. Below, Bess (a junior) and Spainhour (a senior) discuss their respective decisions to come to the U of A, their work in Dr. Timothy Muldoon’s lab, and their future career plans.
UArk BME: Did you always know you wanted to study biomedical engineering?
Spainhour: I went to a smaller high school with a graduating class of about 100 students. My arrival at the University of Arkansas as one of 25,000 undergraduate students was a big transition. Coming to such a large university, I knew that I had to make it smaller somehow, so I wanted to choose a major where the professors would know my name. I have always liked math and science, so I decided to pursue an engineering degree. My uncle graduated from the U of A with a degree in industrial engineering and went on to become a physician, and I wanted to follow in his footsteps. When he was in school, biomedical engineering was not offered at U of A, but I thought among all of the engineering disciplines, biomedical would help me distinguish myself academically when applying to start medical school. Looking back, I had no idea what biomedical engineering really was as a freshman in college, but now I am very pleased to have been a part of such a rigorous and rewarding academic program.
Bess: In high school, I took a Principles of Engineering course as an elective thinking that it was going to be an easy grade, but I learned so much more. After taking that course, I knew that I wanted to be an engineer. When I arrived at the University of Arkansas, I always knew that I wanted to be in the medical field, but I wasn’t sure which major was right for me. For my first semester, I was going back and forth between Chemical Engineering and Biomedical Engineering. When I went on the tour of the Biomedical Engineering department and looked at what they had to offer, I knew that the Biomedical Engineering department was the best fit for me. As a junior at the University of Arkansas, I look back at Decision Day and knew that I made the right decision.
UArk BME: What drew you to the University of Arkansas?
Spainhour: I grew up in Little Rock, Arkansas and my cousins lived in Northwest Arkansas. We would come visit them for Razorback games on the weekends and would always go see the Lights of the Ozarks on the Fayetteville Square on Christmas Eve. I was excited to think I could get to experience that culture, and this drew to me to U of A. When I came for a college tour, I became even more interested. The beauty of the campus, and the small classes and other opportunities offered through the Honors College really drew me in. About the time I started college, my little brother and my mom and dad moved to Fayetteville. I was more convinced when they decided to move that I wanted to be in Fayetteville too. I had looked at many other schools, but U of A just felt right.
Bess: Ever since I was a small child, I was raised a Razorback. My family were die-hard Razorback fans and had always wanted me to go to the University of Arkansas. Before I moved to Fayetteville, I lived in Mountain Home, Arkansas, a small town where everybody knew each other by their first names. The decision to move the Fayetteville my junior year of high school was hard, but when I look back on it, it was one of the best decisions my family had ever made. Throughout my senior year of high school, I was always taking trips to the university and the more I visited, the more I fell in love with the campus. Being able to walk “The Hill” everyday and to see the names of alumni on the sidewalks underneath my feet, inspires me to make my mark on this university.
UArk BME: Can you describe the project you’re working on in Dr. Muldoon’s lab? What role do you each play in the project specifically?
Spainhour: In Dr. Muldoon’s lab, we are working on testing a method of immunotherapy to improve the effects of traditional chemotherapy on a mouse allograft model of colorectal carcinoma. Tumor-associated macrophages (TAMs) are molecules that are recruited to tumors and promote growth and blood supply. CCL2 is the signaling molecule to recruit the TAMs, so our theory is that by blocking CCL2, we will see a decrease in the TAMs and thus, a decrease in growth rate of the tumor. We are using a fluorescently tagged antibody called anti-CCL2 to block the CCL2 signaling molecule, and the fluorescent tag allows us to visualize the macrophages via fluorescence microscopy.
My part of the project is introducing the fluorescent antibodies to the tumor sections and imaging the tumor sections, so the number of macrophages can be quantified. I perform a 6 hour staining protocol that consists of preparing solutions, a series of washing steps, applying a blocking solution, and then applying the antibody. I then mount coverslips and seal the slides. To image the stained slides, I use a fluorescent microscope and a cooled monochrome camera. These images are later analyzed using an image analysis software to prepare the collected data.
So far, we have seen an overall decrease in number of M2 macrophages in the mice treated with the anti-CCL2 immunotherapy and a reduction in the overall tumor growth rate. These preliminary results are very promising, and I am looking forward to beginning the next phase of the experiment where we introduce the immunotherapy treatment in conjunction with chemotherapy.
Bess: After the tumors in the mice have grown, we put the mice to sleep and resect their tumors, which are then analyzed by immunohistochemistry and imaging techniques. Once the tumors have been resected, we freeze them in OCT compound into a cryomold. This is where my part of the project comes in. After our tumors have been frozen in the OCT in a -80°C freezer, I take the tumors and section them into thin slices to be placed on microscope slides. In order to section these tumors, I use a cryotome to make even and clean sections. A cryotome is a machine that allows the user to take a frozen tumor, organoid, or any frozen piece of tissue and make very small sections. The unique aspect of the cryotome is that it is hand-powered. Since the cryotome is hand-powered, it allows for me to be able to slice the tumor into individual sections. Once the section has been made, I take that tumor section and place it onto a microscope slide (usually two sections per slide). I usually make 8 slides per tumor because we have 4 different staining protocols that we use and being able to have 2 slides (or 4 tumor sections) per protocol allows for us to get better results and to see if we are seeing similarities in macrophage numbers.
UArk BME: What’s been the biggest challenge you’ve encountered so far while working in the lab? How did you overcome it?
Spainhour: The first time I was performing a staining protocol I ran out of solution in the middle of the protocol. The protocol was not standardized to the size of the tissue sections being stained. When I was in the middle of staining slides and had two slides left and no more staining solution, I ran out of solution. The project was very time sensitive. To solve this problem, I quickly went back through the protocol to figure out how to make more of the solution. This also required thinking of how many slides I had left to stain and what proportions of each part of the staining mixture I needed to mix up. I calmly did all the calculations, mixed up the remaining staining mixture, and added it to the remaining slides. From this experience, I learned that no matter how well you plan things in advance, there will always be a chance for things not to go as planned.
Bess: When I first started cryosectioning, I had trouble with the tumor section curling after I sliced it with the blade. This is a common problem that most people have when they are sectioning any frozen tissue. I tried everything from adjusting the glass plate to expose more of the blade and adjusting the angle of the blade or the cryomold holder, but no matter what I tried, nothing seemed to work. On one of the practice sections that I was working on, I decided to take a pair of tweezers to hold the section in place as I lifted the glass plate. After I lifted the glass plate, I took a small brush that was in the cryotome and started to slowly unroll it and placed the section on the microscope slide. After using this technique, I found that more of the tumor was being placed onto the slide, which is what we needed for the study. This difficulty allowed me to learn about patience and how to solve problems on my own by using the resources that are around me.
UArk BME: Have you had the chance to share/present your research anywhere?
Spainhour: I was awarded the SURF grant in spring of 2018 to fund a year-long original research project, and as part of the award I was required to present my work at a conference. This fall I presented the preliminary results that we have on our current project at the Gulf Coast Undergraduate Research Symposium at Rice University in Houston, Texas. I was among several hundred undergraduate students from all over the country presenting research. This opportunity was a very special experience, especially since this was the first year the symposium had a section specifically for bioengineering.
UArk BME: Any advice for other undergraduate students who are studying biomedical engineering at the U of A?
Spainhour: Get to know your professors and fellow students and take advantage of having a smaller group of students in your major. More than likely, professors will teach more than one class you will have to take in the BMEG curriculum, so it helps to know them on an individual basis. This not only facilitates a good relationship and opens the door for better communication, but also helps the professors get to know you better and be better able to help you in the future with recommendation letters and networking after college. Getting to know your classmates is also important, because these are the people you will struggle with during the last 3 years of college, and nobody else in your life will understand this struggle like they do. Biomedical engineering is a challenging major, but I have learned a lot and think it has been a great college major for me. The engineering students all have peer mentors their freshman year. This is something each student can really take advantage of. My brothers are in other majors and have not had this opportunity to meet with upperclassmen on a weekly basis. I had the honor of being a peer mentor, and it helped me tremendously as a freshman and even later working with freshmen as their peer mentor.
Bess: Don’t be afraid to ask for help. Being in a research lab here has given me the opportunity to become closer to many of the professors and graduate students that are in the department. Being able to have a mentor like Dr. Muldoon and our graduate student Gage Greening to look up to is something that each student should experience during their time here at the University of Arkansas. The relationships that I have made through this research experience have helped me gain new knowledge not only in the research industry, but also with regard to applications for graduate school, internships, and jobs.
UArk BME: Caroline, you’ll be graduating this coming spring, and Shelby, you’ll be graduating next year. Any idea what you’d like to do after graduating (med school, PhD, industry, etc.)?
Spainhour: During my junior year of college, I decided to change from pre-med to pre-dental, and after I graduate, I plan to attend dental school. I love that dentistry has a preventative approach to medicine. There is a lot of groundbreaking research in the dental field, and it is always changing based on improved technologies and techniques. The progress in the dental field has made it so virtually every problem has a potential solution, and rarely have I heard a dentist say “there is nothing we can do” while shadowing. Being a biomedical engineering major, I am in the business of solving problems, and I look forward to making a career of it.
Bess: After I graduate from the University of Arkansas, I plan on going to graduate school to earn a PhD in Biomedical Engineering. I want to take my education into a research hospital setting to be able to engineer new organs for transplant patients via 3D printing or to create a new cure for terminal cancer patients.