Current Laboratory Staff and Personnel

Principal Investigator (PI)

Aijun

Aijun Wang, Ph.D.

Chancellor's Fellow Professor of Surgery and Biomedical Engineering

Laboratory Manager

Chris Pivetti, M.S. (cdpivetti@ucdavis.edu)

Christopher Pivetti is a scientist for the Department of Surgery, University of California, Davis Health in Sacramento, CA. He received both his bachelor’s degree (2001) and his master’s degree (2004) in general biology from the University of California, San Diego. He serves as the laboratory supervisor and he oversees the daily research operations of five principal investigators. His research interests include using stem cell therapy to treat congenital anomalies such as spina bifida, and diaphragmatic hernia. He also specializes in small animal microsurgery and serves as a microsurgery instructor for the department.

Project Scientist

Priyadarsini Kumar, Ph.D. (pkumar@ucdavis.edu)

Dr. Priya Kumar is the lab's senior scientist with over 25 years of research experience. She obtained her PhD degree from University of California, Davis, and Master’s/Bachelor’s degrees from University of Madras, India. Her research focuses on stem cells and stem cell derived extracellular vesicles for the treatment of neurodegenerative diseases. She led the GMP production of our placenta derived mesenchymal stem cells (PMSCs) for our team, which led to the successful approval of the IND from the FDA to conduct a Phase1/2a spina bifida clinical trial, which started in 2021. Her other research focuses on utilizing PMSC-derived extracellular vesicles (PMSC-EVs) to develop a serum-free cell-free product for other clinical applications, such as adult acquired spinal cord injury. Teaching has always been her passion and she loves to mentor aspiring scientists. During her free time, she loves cooking Indian food, watching soap operas in her native language (Tamil), reading books about inspiring personalities, and loves taking care of neighborhood cats.

Scientific Grant Writers

Natalie Tobin, B.S. (ntobin@ucdavis.edu)

Natalie earned a Bachelor of Science degree in Human Biology from UC Irvine. She is working towards her Master of Business Administration at UC Davis with an emphasis in healthcare and biotechnology. She currently manages writing projects in the lab and provides support to Dr. Wang's longtime collaborator Dr. Diana Farmer. In her free time, Natalie enjoys hiking, traveling to new countries, and watching movies.

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Fallon Duffy, B.S. (ftduffy@ucdavis.edu)

Fallon earned her Bachelor of Science degree in General Biology from UC Davis with minors in Professional Writing and Religious Studies. Along with Natalie, she helps manage the writing project in the lab. She has a particular interest in scientific writing and editing which she explored during her undergraduate degree, including an intership writing news article for the UC Davis College of Engineering. Outside of lab, Fallon likes to shop for vintage clothes, see live musicals, and bake new recipes.

Postdoctoral Fellows

Kewa Gao, M.D., Ph.D. (kwgao@ucdavis.edu)

Dr. Kewa Gao is a Shriners Hospitals for Children Postdoctoral Fellow. She was trained as a general and plastic surgeon (MD). Her research focuses on genetic disease treatment, such as hemophilia A and sickle cell disease, by stem cell transplantation and gene editing. She is also interested in developing biomaterial and stem cell-based treatment for wound healing. In her spare time, Kewa enjoys skiing, scuba diving, and photography.

Luis E. Contreras-Llano, Ph.D. (lecontrerasllano@ucdavis.edu)

Dr. Luis Contreras-Llano holds B.E and M.S. degrees in Biotechnology and has carried out research in laboratories in Mexico, Spain, and the US in areas including plant & microbial biochemistry, molecular biology, and synthetic biology. Luis obtained his Ph.D. in Biochemistry, Molecular, Cellular and Developmental Biology at the University of California, Davis under the supervision of Dr. Cheemeng Tan, where his work focused on developing cell-free protein expression systems (PURE and WCE), synthetic (artificial cells) and semi-synthetic cells (cyborg cells). After his PhD, he worked at the digital cell biology company Berkeley Lights as a Molecular Biology Scientist where he developed high-throughput screening assays for proteins of relevance in agriculture using cell-free expression systems. His research has been published in journals as Advanced Science, Nature Chem Bio, Nature Comms, ACS Appl Mat & Interfaces, mBio, and has been featured in Scientific American, Popular Mechanics, Advanced Science News, BGR, and the Nature Portfolio Bioengineering Community. He joins the laboratory of Dr. Aijun Wang with the aim of developing new therapeutic approaches using a combination of synthetic biology, materials science, and molecular biology tools.

Kaitlin Clark, Ph.D. (kcclark@ucdavis.edu)

Dr. Kaitlin Clark (Kasey) is a postdoctoral fellow in the lab. She received her Ph.D. in the Biochemistry, Molecular, Cellular and Developmental Biology (BMCDB) Program, at UC Davis, and is emphasizing in translational research. She received her bachelor’s degree from UC Davis and her master’s degree in Stem Cell biology from CSU Sacramento. Kasey started her research career at the UC Davis School of Veterinary Medicine in 2009 focusing on mesenchymal stem cell (MSC) treatments for animals. She is currently investigating the use of placenta derived MSCs (PMSCs) for the treatment of spina bifida in English Bulldogs. Kasey’s main research focus is the immunoregulatory properties of PMSCs and is also investigating the use of PMSC derived extracellular vesicles (PMSC-EVs) for the treatment of multiple sclerosis. In her free time, Kasey enjoys playing sports, riding her horses and spending time with her rescue dogs.

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Yi Cheng, MD, PhD

Dr. Yi Cheng (Lottie) is a postdoctoral fellow in the lab and a vascular surgeon at Nanjing Drum Tower Hospital. She received her Ph.D. degree in Nanjing University Medical School. She is working on gene delivery, wound healing, microneedle patch and vascular stents. She likes drawing and crafts.

Hengyue Song, M.D., PhD (hyusong@ucdavis.edu)

Dr. Hengyue Song is a postdoctoral fellow in the lab and a trained plastic surgeon (MD). She is now focusing on burn wound healing, tissue engineering, and gene editing research projects. Outside the lab, Hengyue is a photographer, a music aficionado, and a museum lover.

Research Surgical Residents

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Jose Castillo, M.D. (jcastillo@ucdavis.edu)

Dr. Jose Castillo is a neurosurgical resident at UC Davis with an interest in spinal surgery. He is from Oakland, CA and moved to Virginia after high school, where he drove school buses and worked his way up to driving a motorcoach transporting people all around the east coast. When he returned to school, he completed a bachelor’s degree in physics from George Mason University and then obtained his medical degree from Virginia Commonwealth University. His work revolves around studying cell free therapies for the treatment of spinal cord injury using extracellular vesicles from placenta derived mesenchymal stem cells.

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Elizabeth Reynolds, M.D. (elreynolds@ucdavis.edu)

Dr Elizabeth Reynolds is a general surgery resident at Brooke Army Medical Center. She completed her undergraduate education at Syracuse University, MS in biology at Duke University, and MD at Uniformed Services University of Health Sciences. She is interested in pediatric surgery and applications of stem cell therapy on treatment of congenital diseases. In her spare time, she enjoys spending time with her husband and dogs on the trails, training for marathons, and listening to audiobooks.

Nataliya Bahatyrevich, M.D. (nbahatyrevich@ucdavis.edu)

Dr. Nataliya Bahatyrevich is an Integrated Cardiothoracic Surgery resident at UC Davis with an interest in heart failure and transplantation. She is working on developing a blood vessel denudation animal model as well as vascular grafts for treatment of coronary artery disease and peripheral vascular disease. She is also interested in studying targeted cellular therapy to treat chronic heart failure.

PhD Students

Yongheng Wang, M.S. (yhgwang@ucdavis.edu)

Yongheng is a Ph.D. student in Biomedical Engineering. He is working on CRISPR in vivo editing, 3D bioprinting, tissue engineering and single cell omics. He likes playing basketball, skiing, hiking and writing.

Tanner Henson, B.S. (tjhenson@ucdavis.edu)

Tanner Henson is a Ph.D student in the Biomedical Engineering program at University of California, Davis. His current research is focused on the use of artificial cells in gene therapy. (co-advised by Professor Cheemeng Tan). During his free time, he enjoys playing a multitude of video games and enjoys watching cooking shows on the side, even though cooking is not a skill of his.

David Wang, B.S. (dtwang@ucdavis.edu)

David is a Ph.D. student in the Biomedical Engineering Graduate Group (BMEGG). He is working on engineering extracellular vesicles (EVs) for central nervous system indications, namely Alzheimer's Disease. This includes engineering EV surfaces and cargo to modulate processes such as neuroinflammation, myelination and angiogenesis. In his free time, David enjoys playing piano, hiking and playing tennis.

Yofi Wyle, M.A. (ybwyle@ucdavis.edu)

Yofi is an MCIP PhD student with a passion for applied stem cell research and regenerative medicine. Yofi is hoping to spend his graduate studies developing organoid systems to generate stem cell-derived tissues for pediatric regeneration. Currently, he is working to implement organoid systems to model and treat myelomeningocele and congenital diaphragmatic hernia.

Kuan-Wei Huang

Kuan-Wei Huang is a PhD. student in Biomedical Engineering Graduate Group (BMEGG) at University of California, Davis, co-advised by Professor Randy Carney. His research focuses on examining autotropism of EV's derived from primary brain cancer cells in vitro and in vivo. During his free time, he enjoys watching movies, snowboarding and playing with cats.

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Abigail Humphries (alhumphries@ucdavis.edu)

Abby is a PhD student in the Biomedical Engineering Graduate Group (BMEGG) co-advised by Professor Randy Carney. She earned her Bachelor of Science in Biomedical Engineering with a minor in History from UC Davis. Her research project focuses on engineering liposomes and extracellular vesicles with the goal of applying them to spina bifida care. In her free time, Abby enjoys outdoor activities like swimming, cycling, running, and hiking.

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Nhung Au (ntau@ucdavis.edu)

Nhung is a PhD student in the Pharmacology & Toxicology (PTX) program at the University of California, Davis. Her research project focuses on exploring the potential of Placental Mesenchymal Stem Cell-derived Extracellular Vesicles (PMSC-EVs) as a delivery system for novel anticancer agents. This approach aims to overcome the blood-brain barrier (BBB), a major challenge in glioblastoma treatment, and reach the brain tumor sites more effectively (Co-advised by Dr. YuanPei Li). In her free time, she enjoys cooking various types of dishes, reading books, and exploring nature.

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Arya Lall (ailall@ucdavis.edu)

Arya Lall is a Chemistry and Chemical Biology PhD student, co-advised by Dr. Elizabeth Neumann. She received her Bachelor of Arts in Chemistry from UC Berkeley. Her research focuses on using single-cell spatialomics to understand neurological and central nervous system development and related diseases. In her free time, she loves to read, bake, cook, and hike.

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Siyu Lin (siylin@ucdavis.edu)

Siyu Lin is a Ph.D. student in the Biomedical Engineering program at the University of California, Davis. Her current research focuses on using spatial transcriptomics to decipher disease mechanisms and discover potential therapies. During her free time, she enjoys playing TRPG, painting, and caring for her betta fish.

Master’s Students & CIRM Bridges Students

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Amanda Ratcliff (ajr172@humboldt.edu)

Amanda earned her Bachelor of Science in Cellular/Molecular Biology with a minor in Chemistry from Cal Poly Humboldt. Her research is centered around treatment of spinal cord injury using placental mesenchymal stem cells (PMSCs) and PMSC-derived extracellular vesicles (PMSC-EVs). In her free time, Amanda enjoys Muay Thai, Jiu Jitsu, video games, and spending time with her dog Mango.

Ethan Nabeta, B.S.

Ethan is a master's student in the CSU-Sacramento Stem Cell Program at UC Davis. He is working on tuning hydrogels for spina bifida treatment and looks forward to gaining further insight into alternative applications of hydrogels and other biomaterials. In his free time, Ethan enjoys beach and forest hiking, playing video games, tasting new foods, and critiquing films.

Grace Garcia, B.S.

Grace earned her Bachelor's of Science in Biomedical Sciences and is currently working towards her Master's of Arts in Stem Cell Research from California State University, Sacramento. Grace's project proposal includes working on the vascular team to help evaluate the capturing ability of a vascular graft lined with a LXW7 ligand on capturing circulating endothelial cells. The hopes are to replace the current technology used in hemodialysis. In her free time, she enjoys being outside, whether that be hiking, floating on the river, or camping.

Samuel Jay Emerson, B.S. (sjemerson@ucdavis.edu)

Sam earned his Bachelor of Science in Cellular/Molecular Biology with a minor in Chemistry from Cal Poly Humboldt. His research is centered around the engineering and manufacturing of extracellular vesicles as a treatment for neurodegenerative diseases, as well as developing biomimetic nanovesicles for drug delivery. In his free time, Sam likes to play guitar and piano, watch movies, play video games, cook and play golf.

Emma Loll, B.S., B.A. (egloll@ucdavis.edu)

Emma earned a Bachelor of Science degree in Neurobiology, Physiology & Behavior, and a Bachelor of Arts degree in Spanish from UC Davis. She began working at the Center for Surgical Bioengineering in 2021 as a Junior Specialist, where she was responsible for managing general lab operations, providing perioperative care for sheep & rats, and assisting with histology for various animal studies. Emma is now a master's student currently working towards her M.S. in Integrative Pathobiology through the UCD School of Veterinary Medicine. She is currently researching new methods to modify placental mesenchymal stem cell-derived extracellular vesicles (PMSC-EVs) using click chemistry to create a targeted, cell-free treatment for multiple sclerosis alongside Dr. Clark. Emma is also interested in the pathophysiology of glioblastoma and engineering EVs to treat invasive brain cancer. Outside of research, Emma enjoys skiing, hiking, listening to music, spending time with loved ones, and snuggling up with her goldendoodle (Churro) and black cat (Soy).

In addition to her Master's degree work, Emma has also recently transitioned to a Financial Analyst role, to continue overseeing lab operations and acquiring products, materials, and services for the group and most importantly, for the Phase II clinical trial, the CuRe Trial. (csbfinance@ucdavis.edu)

Arundhuti Sanyal, B.S.

Arundhuti earned her B.S. in Biomedical Engineering with a minor in Biology from UC Irvine. Her research focuses on utilizing single-cell multiomics to detect dysregulated molecular pathways and develop targeted gene therapy solutions. Specifically, her work involves consolidating transcriptomics, proteomics, and metabolomics data to identify differentially expressed genes in neurological diseases, such as Canavan disease, glioblastoma multiforme, and Rett syndrome. In her free time, Arundhuti enjoys reading, hiking, watching movies, and traveling.

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Isha Maisuriya, B.Tech (ismasuriya@ucdavis.edu)

Isha is a Master’s student in the Biomedical Engineering Graduate Group (BMEGG). She earned her B.Tech in Biotechnology from SRM IST, India. She is passionate about stem cell research and genetic engineering. Isha's research focuses on engineering and exploring the potential of Lipid Raft Nanovesicles (LRNVs) for gene-editing as well as drug-delivery. In her free time, Isha enjoys playing table tennis, hiking, cooking and traveling.

Staff Research Associates and Junior Specialists

Samantha Avallone, B.S.

Samantha has a Bachelor of Science in Biological Sciences and Anthropology from the University of California, Davis. She is currently a Staff Research Associate in the lab and assists with general lab operations, as well as performs histology and cell culture work. In her spare time, she likes to play flute and alto saxophone, crochet, and bike.

Juan-Maria G. Lopez, B.S.

Juan earned his Bachelor of Science in Biology with an emphasis in Cellular and Molecular Biology. He was recently a Humboldt State University CIRM Bridges Scholar in the Center for Surgical Bioengineering. Juan is currently a Junior Specialist in the lab and his current research focuses on the delivery system for the sustained release of extracellular vesicles (EVs) and on increasing EV production. Outside the lab, Juan is a sculpture artist who creates handcrafted silver and stone jewelry. He also enjoys playing soccer, swimming, and cooking.

Annie Jensen, B.S.

Annie graduated from Humboldt State University with a Bachelor of Science in Cellular and Molecular Biology with a minor in Chemistry. She was a part of the CIRM Bridges 3.0 program at Stanford University. Currently, Annie is a Junior Specialist in the lab and part of the cell culture team for the Spina Bifida Clinical Trial. She enjoys reading, hiking, paddle boarding, and baking.

Matileen Cranick, B.S.

Mattie earned a B.S. in Chemistry with a concentration in Biochemistry from UC Irvine. Mattie also recently completed the Health Professions Postbaccalaureate program at UC Davis. Currently, Mattie is a Junior Specialist in the lab, working on the lipid nanoparticle delivery of mRNA as a therapy for cerebral palsy. Mattie is interested in engineering scaffold materials and nanoparticles as regenerative therapies for spinal cord injury repair. In her free time, Mattie enjoys flag football, pickleball, and exploring new hikes in Tahoe.

Weidi Zhang, B.S.

Weidi received his Bachelor of Science in Molecular Biology and Biochemistry from the University of California, Davis. He is currently a Junior Specialist in the lab, studying disease mechanisms based on multi-omics spatial single cell technologies. His previous research includes genetic disease modeling, high-throughput drug screening, and gene editing. Outside the Lab, Weidi enjoys sleeping.

Medical Students

Sirjan Mor, M.S. (simor@ucdavis.edu)

Sirjan is a second-year medical student at the UC Davis School of Medicine. She received her Bachelor of Science degree in Biological Sciences with a minor in Spanish at the University of Southern California (USC). She also received her master’s degree in Stem Cells and Regenerative Medicine from USC. In the lab, her interests include spinal cord injury repair using placental mesenchymal stem cells (PMSCs) and PMSC-derived extracellular vesicles (PMSC-EVs). She is specifically interested in the roles of astrocytes and microglia in spinal cord injury repair. In her free time, she loves to dance Salsa, try new foods, and watch reality TV shows.

Anastasiya Stasyuk, B.S. (astasyuk@ucdavis.edu)

Anastasiya is a medical student at UC Davis School of Medicine, Class of 2024. She has a Bachelor of Science in Microbiology from UC Santa Barbara and has previously studied cellular stress response and antibiotic resistance. Her current research involves improving treatment options for congenital diaphragmatic hernia and she is interested in exploring new applications of tissue engineering. Besides research, Anastasiya enjoys running, hiking, and painting.

Blaine Baker, B.S.

Blaine is a medical student at the UC Davis School of Medicine. They have a Bachelor of Science in Biochemistry from Sonoma State University and have studied structural biochemistry at UC San Diego and gene editing/DNA repair at Graphite Bio. Their current research is focused on the production, isolation, and uptake of extracellular vesicles as well as engineering EVs for the treatment of Alzheimer’s Disease. During their free time, they enjoy hanging out with their fiancé, family, friends, and their Bernedoodle Benny. They love chess, slam poetry, contemporary art, fashion, and retro video games.

Undergraduate Students

Kathy Gyehyun (solee@ucdavis.edu)

Kathy is a fifth-year undergraduate student at UC Davis, majoring in global disease biology and minoring in human physiology. She works in the Wang lab as a student researcher and focuses on scoring motor function for spina bifida animals and seeing the effectiveness of the stem cell matrix. In her free time, she likes to play tennis and cook.

Jianing Chen (jnichen@ucdavis.edu)

Jianing is a fourth-year undergraduate BME student. She is actively assisting Dake on some of his projects. She currently focuses on designing a growth factor and EV control release system for a carotid artery denudation model and neural protection. In her free time, Jianing likes to grow a lot of plants.

Han Zhang (qwezhang@ucdavis.edu)

Han is a fourth-year undergraduate student majoring in Biomedical Engineering. He joined this lab as a student researcher. He is working on 3D bioprinting of multifunctional bioengineered scaffold to mimic extracellular matrix for spina bifida treatment. In his free time, Han enjoys playing golf and badminton.

Siraj Gidda (ssgidda@ucdavis.edu)

Siraj is currently a fourth-year undergraduate student majoring in global disease biology and minoring in public health sciences at the University of California, Davis. He is currently assisting in the development and optimization of extracellular vesicle (EV) mimicking technologies for vascular repair and regeneration. In his free time, he enjoys biking, gaming, traveling, and spending time with his loved ones.