Ph.D. Students
Breezy Brock, B.S.
V.M.D./Ph.D. Student
Breezy Brock earned her B.S. in Microbiology from Northern Arizona University in 2022, where she conducted undergraduate research with Dr. Crystal Hepp and Dr. Viacheslav Fofanov, focusing on environmental pathogen surveillance to understand their temporal and geographic spread. Breezy is a fourth-year VMD/Ph.D. candidate at the University of Pennsylvania, where her thesis focuses on developing next-generation mRNA-based HIV vaccine immunogens. Her work involves introducing cytoplasmic tail mutations into a stabilized trimeric Env protein to enhance surface expression and localization to specialized plasma membrane microdomains. This project aims to define how antigen availability and microdomain localization influence B cell precursor priming, with the goal of informing immunogen design strategies for HIV and other complex viruses. Guided by Dr. Drew Weissman and Dr. Edward Kreider, Breezy is committed to the One Health Initiative, developing cross-species vaccine strategies grounded in virology and immunology while fostering interdisciplinary collaboration to ensure that vaccine solutions address both human and animal health challenges in the face of emerging and existing pathogens.
Nicholas A. Cerda, B.S.
He/Him/His
Nicholas Cerda earned his B.S. in Biology at the University of Texas at Austin in 2021. While enrolled at the University of Texas, Nicholas was a member of the Croyle lab, where he completed his honors thesis. After entering Penn, Nicholas’ passion for vaccines and formulation science led him to be co-mentored by Drs. Drew Weissman and Hamideh Parhiz. His thesis work focuses on the area of lipid nanoparticles and their interactions with the immune system. He is also involved in several other projects such as lipid nanoparticle targeting. While not working in the lab, Nicholas also works on developing leadership skills through serving as an officer for the biomedical graduate student association board. Following his doctoral studies, Nicholas plans to pursue a postdoctoral position at the Vaccine Research Center in Gaithersburg.
Roxanne E. Perez Tremble, B.S.
Roxanne E. Perez Tremble received her Bachelor of Science in Neuroscience, with distinction in her major and a minor in Psychology, from Temple University in 2023. As an undergraduate, she conducted research in the lab of Dr. Lisa Briand, where she studied the role of microglia in substance use disorder during adolescence. She also participated in the NURO/SIREN summer research program at the University of Michigan, working in Dr. Sara Aton’s lab to investigate the effects of a hypnotic compound on sleep restoration in a mouse model of Fragile X syndrome. In addition, she worked under the mentorship of Dr. Kurt Brunden at the University of Pennsylvania, where she examined the therapeutic potential of a microtubule-stabilizing agent in models of Alzheimer’s disease.
Following graduation, she was a scholar in the Post-Baccalaureate Research Education Program (PREP) at the University of Pennsylvania (2023–2024). During this time, she worked in the lab of Dr. Erica Korb, where she investigated the role of the histone variant H2BE in neurodevelopment, with a focus on how histone chaperones influence its incorporation and eviction from chromatin.
In 2024, she joined the Cell and Molecular Biology Graduate Group at the University of Pennsylvania and became a member of the Weissman Lab in 2025, where she is co-mentored by Drs. Lesley Chaboub and Jilian Melamed. Her current research interests include RNA-based therapeutics, particularly mRNA–lipid nanoparticle (LNP) delivery systems and their targeted application to the brain.
Rose Razavi, B.S.
Rose Razavi earned her B.S. in biochemistry from SUNY Stony Brook University in 2023. During her four years of undergraduate studies, she also gained industry experience at Nanoprobes Inc. under the guidance of Dr. James Hainfeld. She developed a targeted protein nanoparticle therapeutic for the treatment of triple-negative breast cancer and pancreatic cancer. The therapy showed remarkable effectiveness in preclinical trials, leading to a patent application. At the University of Pennsylvania, Rose has continued her research journey in Dr. Weissman’s laboratory under the mentorship of Dr. Jilian Melamed and Dr. Drew Weissman. Her thesis is focused on developing a targeted mRNA lipid nanoparticle therapeutic to treat Type I Diabetes. In her free time, Rose enjoys painting, rowing, baking, hiking, and exploring new hobbies.