Research Team

Lab Research Team: Dr. David Gerber; Lisa Samuelson, BA; Cai-Bin Cui, MD, MS, PhD; Caixia Jin, PhD; Yangzhong Sun, MD

In addition to Dr. Gerber, the team includes the following:  

Lisa Samuelson, BA, majored in Biology and Exercise and Sports Science at the University of North Carolina at Chapel Hill. After graduating, she began working in the lab with Dr. Gerber. She is currently pursuing a Master’s degree in Pathology and Laboratory Medicine. Her research focuses on restorative therapy to replace lost islet mass in the treatment of Type I diabetes. Islet transplantation has proven effective at curing diabetes, but its use is severely limited due to the necessity for a large number of transplantable islets as well as a shortage of suitable donors. An alternative therapy would include a robust, easily accessible cellular population to replace damaged islets and restore insulin secretion. We have isolated a pancreatic progenitor cell, using stem cell antigen 1 (Sca-1), a marker of hematopoietic stem cells. This population is highly proliferative, capable of differentiation toward the myriad cell types of the mature adult pancreas and produces basal amounts of insulin. We theorize that using this cell population, in addition to a bioreactor type culture mechanism that mimics the niche of the in vivo pancreas, we can create a viable cell source of insulin-producing cells that can be used for the transplant and treatment of diabetes.

Cai-Bin Cui, MD, MS, PhD, finished his postdoctoral training in the field of regenerative medicine at the University of North Carolina at Chapel Hill and became a research assistant professor. He joined the Transplant Lab in 2008. Dr. Cui’s research interests are in stem/progenitor cells and regenerative medicine. Since joining the lab, he has developed three projects: (1) Dissecting the transcription factor network controlling pancreatic beta cell differentiation by using high-throughput screening techniques to discover novel small molecule inducers that are able to promote regeneration of pancreatic endocrine cells. (2) Isolating and characterizing a human pancreatic stem/progenitor cell population and developing a long-lasting functional pancreatic islet for long-term correction of diabetes based on native pancreatic islet matrix. (3) Developing a 3D functional liver unit for in vivo transplantation. This involves re-endothelialization of vascular channels and parenchymal repopulation with hepatic stem/progenitor cells into decellularized liver biomatrix scaffold.

Caixia Jin
, PhD, has been in the lab since 2009. Her post-doctoral research includes isolating and establishing Sca-1 positive hepatic progenitor cell lines from wild type adult mice. The Sca-1+ HPC cells can be continuously cultivated over 30 passages in vitro and are non-tumorigenic. Proliferation and differentiation characteristics of HPC cells are the focus of ongoing studies.

Yangzhong Sun, MD, is a visiting professor in the Division of Abdominal Transplant Surgery, School of Medicine, University of North Carolina at Chapel Hill, investigating the role of liver stem cells and the development of liver cancer. Hepatic Oval cells are small, oval shaped epithelial cells identified in the liver during normal embryonic development. For many years the finding of preneoplastic nodules in the liver during experimental induction of hepatocellular carcinoma was interpreted to support the hypothesis that HCC arose by dedifferentiation of mature liver cells. It had not yet been proved that hepatic oval cell is the original cell of liver cancer, but there are some common characteristics in liver stem cells and liver cancer cells. Analysis of the cells in liver cancer support the presence of cells with stem-cell properties (i.e., immortality, transplantability, and resistance to therapy). However, definitive markers for these putative cancer stem cells have not yet been found and a liver cancer stem cell has not been isolated.

Collaborators

Martin King, PhD, is a professor of Biotextiles and Textile Technology at North Carolina State University. Specifically we have been working with him to expand our cells on small nanofiber scaffolds that he and his students create. His website www.tx.ncsu.edu/biomedicaltextileslab gives an overview of his work, with the overall goal to use his micro engineered textile materials to grow cells and eventually implant them into patients to treat various diseases.

Lola Reid, PhD, works with liver and pancreatic stem cells. She is currently focusing her attention on methods of transplanting human fetal progenitor cells from the liver and pancreas. Rachael Turner, a graduate student in Dr. Reid’s lab and whom Dr. Gerber mentors, is using different gel type materials to transplant cells into mice livers and study the effects and how effective the gels are at keeping the cells alive and localized in the liver. Dr. Reid has also done a lot of work with Dr. Cui and his work with creating a decellularized islet structure.
www.med.unc.edu/physiolo/faculty/reid/fac_reid
www.med.unc.edu/transmed
www.med.unc.edu/transmed/current-trainees-1/entered-in-2006/RachaelTurner/joe-burgents

Bob Dennis, PhD, is in the Department of Biomedical Engineering, which is a joint program between the University of North Carolina at Chapel Hill and North Carolina State University. He has created small rotating wall vessel bioreactors that create a 3-D environment to grow cells. We believe this will be a distinct advantage over growing them in 2-D on flat tissue culture dishes which ultimately change their morphology and fate.
www.bme.unc.edu/~bob/

Jian Jin, PhD, is Associate Professor and Director, Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery in the Eshelman School of Pharmacy at the University of North Carolina at Chapel Hill. His research includes conducting high-throughput screening of structurally diversified small molecule libraries to identify small molecule inducers that promote pancreatic β cell regeneration. The goals are to identify small molecules capable of promoting PDX-1 and NGN3 expression by high-throughput screening of small molecule libraries and to confirm small molecule hits via biological activities, chemical identity and purity verification, and carrying out initial structure activity relationships (SAR) study.
pharmacy.unc.edu/faculty-research/faculty-directory/jianjin/

Jorge Piedrahita, PhD, is Professor of Genomics in the Department of Molecular Biomedical Sciences at North Carolina State University. His research focuses on the ability to efficiently manipulate the swine genome to generate genetically modified animals with the potential to provide a novel source of cells/tissues for clinical applications. We are collaborating in the development of genetically modified swine capable of high-level engraftment with human hepatocytes. This large animal model capable of engraftment and expansion of human hepatocytes will be the first step toward the development of a system to generate large numbers of human hepatocytes for drug metabolism studies, development and testing of drugs targeting liver disease, testing of stem cells capable of generating human hepatocytes in an in vivo model, and eventually to the development of cells that can be used for transplantation.
www.cvm.ncsu.edu/mbs/personnel/piedrahita_jorge.html