Post-doctoral Staff
Dr. Hunter Oppler
Dr. Oppler is a postdoctoral researcher at the Preclinical Research Center, whose work sits at the intersection of preclinical disease modeling, regenerative medicine translation, and animal welfare science. His research focuses on refining nonhuman primate models to improve both animal wellbeing and the predictive value of preclinical research. His research centers on evaluating innovative biomedical and regenerative medicine therapies while advancing model refinement practices that improve the animal experience and strengthen translational relevance. A key component of Hunter’s work examines how unintentionally induced stress and other model-related variables can alter critical immunologic and physiologic outcome measures. By identifying and minimizing these confounded, he helps ensure that data generated in primates more accurately reflects the targe clinical population. Through this work, Hunter directly contributes to better animal care, more reproducible data, and more reliable late-stage preclinical decision-making. His expertise in welfare-centered model refinement strengthens every aspect of MN-BRIDGE supported research and plays an important role in advancing regenerative medicine therapies toward safe and successful clinical translation.
Surgical Residents
Dr. Cheyenna Espinoza
Dr. Espinoza is a general surgery resident at the University of Minnesota currently completing a dedicated two-year research fellowship in the Preclinical Research Center (PCRC) under the mentorship of Dr. Melanie Graham. As a surgeon-scientist, her work through the Minnesota BRIDGE program focuses on translational obesity research and islet cell biology, using advanced preclinical models to address clinically driven questions central to academic surgery. In addition, she has led the development and refinement of minimally invasive surgical techniques and novel delivery methods for regenerative medicine therapies in translational models. This work is designed to improve procedural reproducibility, reduce surgical burden, and better align preclinical delivery approaches with clinically realistic interventions. Training within a multidisciplinary regenerative medicine environment, she contributes to the refinement and application of primate models while working alongside experts in immunology, pathology, transplantation, bariatric surgery, and microbiology. This collaborative setting provides direct exposure to the complexity of late-stage preclinical research and the considerations required to move toward clinical application. Her laboratory training emphasizes rigorous experimental design, critical thinking, experimental design, and rigorous data interpretation, skills that directly support her development as an academic surgeon capable of bridging mechanistic research with patient-centered surgical innovation.
Dr. Cole Myers
Dr. Myers is a general surgery resident and T32 trainee in the Department of Surgery at the University of Minnesota who is developing new approach methodologies that complement and strengthen translational models. Through the MN-BRIDGE collaboration, he leads the surgical development of implantation sites designed to accommodate stem cell-based products including sites that support containment, retrievability, and the specialized biological conditions required for regenerative therapies. In parallel, his research focuses on understanding how biological and procedural variables influence commonly measured immune and physiologic markers in preclinical studies. By systematically characterizing these sources of variability, he improves the consistency and interpretability of NHP data across studies. Building on these datasets, he is developing predictive models that integrate longitudinal clinical and biological measures, to anticipate outcomes with fewer animals. This approach enables more efficient study design and dramatically reduces the number of animals required while preserving translational rigor. Together, his work advances surgical model innovation, improves animal care, reduces animal use and enhances the translational impact of regenerative medicine research supported by MN-BRIDGE
Graduate Students
Sierra Palmer, MPH
Sierra is a PhD Candidate in the College of Veterinary medicine’s Veterinary Science program. Sierra’s research focuses on improving the daily experience of animals in biomedical research setting. Her work advances approaches that support behavioral health, engagement, and resilience in primates, while simultaneously strengthening the quality and reliability of preclinical research data. Her projects center on the development and application of behavioral management tools and cooperative training methods that promote predictability, agency, and reduced reactivity during routine research procedures. By improving the animal experience, this work minimizes stress related confounding and directly enhances data quality and reproducibility – addressing a key driver of translational failure in late-stage preclinical research. In addition to her research, Sierra collaborates with internal and external labs, trainees, and research personnel to provide hands-on teaching and mentoring in foundational behavioral management, animal training, and troubleshooting of study or subject specific behavioral goals. Through this work, she helps disseminate best practices that improve animal wellbeing while strengthening the scientific rigor of MN-BRIDGE supported regenerative medicine studies.
Sydney Phu
Sydney is a PhD student in the Comparative and Molecular Biosciences program at the University of Minnesota. Her research focuses on developing and qualifying noninvasive biomarkers and point-of-care testing approaches that strengthen the translational relevance of preclinical studies. Her work advances strategies for monitoring health, immune status, and injury using minimally invasive biofluids, with a particular emphasis on urine based biomarkers. By enabling frequent, longitudinal sampling without disrupting animal wellbeing, her research generates richer, higher-resolution datasets than are possible with invasive approaches. This increased data density improves sensitivity to early biologic changes, enhances statistical power, and allows more precise characterization of disease trajectory and treatment responses. In parallel, she validates point-of-care technologies for rapid health assessment and multiplexed assays that deliver clinically meaningful information from very small sample amounts, reducing procedural burden while supporting timely, data informed clinical decision-making. Together, these approaches improve both forward and reverse translation by aligning preclinical monitoring strategies with clinical practice and strengthening data quality across MN-BRIDGE supported programs
Westley Timmerman
Westley is a graduate student in the Bioinformatics and Computational Biology program at the University of Minnesota. Through his role at the Preclinical Research Center, he works directly with complex pharmacokinetic and immunologic datasets generated from primate studies, gaining hands-on experience with real-world translational data. His work integrates computational and bioinformatic approaches with active preclinical research, allowing him to develop and apply analytical tools that support data integration, modeling, and interpretation across studies. By working with datasets derived from rigorous, well-characterized preclinical models, he is trained to address the challenges of variability, scale, and complexity that often limit translational insight. Westley contributes to strengthening the analytical foundation of MN-BRIDGE–supported research while developing the computational expertise needed to support predictive modeling, data-driven decision-making, and efficient translation of regenerative medicine therapies.
Undergraduate Students
Namitha Narayan
Namitha Narayan is an undergraduate senior at Carleton College majoring in Biology on the pre-medical track. Through her work with the Primate Immunobiology Core and the Transplant Tolerance Laboratory at the University of Minnesota, she is gaining early exposure to immunology and translational biomedical research in a preclinical setting. In this role, she is developing foundational skills in experimental design, data analysis, and scientific communication while contributing to ongoing research focused on immune monitoring and transplant tolerance. This experience provides hands-on insight into how mechanistic immunology informs translational decision-making and supports the development of clinically relevant regenerative medicine therapies. By engaging undergraduate trainees in active MN-BRIDGE–supported research, the program helps build an early pipeline of future clinicians and scientists with a grounded understanding of translational research, collaborative science, and responsible biomedical innovation.
Diego Paulin
Diego Paulin is an undergraduate student studying Biochemistry and Molecular Biology at Gustavus Adolphus College. After developing an interest in immunology and biomedical research, he joined the Primate Immunobiology Core and the Transplant Tolerance Laboratory at the University of Minnesota, where he has been engaged in hands-on research since the summer of 2024. His training focuses on the development and validation of immunologic assays used to characterize the immune landscape relevant to cell therapy and regenerative medicine applications. Through this work, he is gaining experience in experimental rigor, assay reproducibility, and data interpretation within a translational research environment. This early exposure to clinically relevant immunology and regenerative medicine research supports his goal of pursuing medical training and contributes to MN-BRIDGE’s broader mission of building a diverse, well-prepared pipeline of future physician-scientists.