Lab Members
Stephan Rogalla, MD, PhD
Clinical Assistant Professor in Gastroenterology & Hepatology
Dr. Rogalla completed his medical training at the Charité, medical school of Humboldt University, in Berlin, Germany. He joined the Molecular Imaging Program at Stanford (MIPS) in 2012 for a postdoctoral fellowship in early cancer detection under his principal investigator, Dr. Christopher Contag. He finished the fellowship 2015 and was promoted to instructor. In 2017 he transitioned to work under the supervision of Dr. Sam Gambhir in MIPS. Since 2020, he has been a Clinical Assistant Professor and the Principal Investigator of the Rogalla Lab.
Since 2016, Dr. Rogalla has been co-chair of the Intra-Operative Imaging Study Group of the European Society of Molecular Imaging (ESMI) (2016-Present). He is a member of the American Gastroenterological Association (AGA), American Society of Clinical Oncology (ASCO), American Association for Cancer Research (AACR), ESMI and World Molecular Imaging Society (WMIS).
Dr. Rogalla's current research is in the field of early cancer detection using targeted molecular spies to highlight (pre)cancerous lesions and developing novel imaging tools for fluorescence and spectroscopic imaging. He also aims to improve precision medicine in autoimmune disorders like inflammatory bowel disease and gastrointestinal cancer.
Faculty
John Gubatan, MD
Instructor in Gastroenterology & Hepatology
Dr. Gubatan's research is focused on translational studies using single-cell genomics to understand mechanisms of biologic therapy failure, elucidate the role of host immune and gut microbiome interactions in the pathogenesis of inflammatory bowel disease (IBD), and develop precision medicine strategies to improve outcomes in patients with IBD.
Derek Holman, PhD
Instructor in Gastroenterology & Hepatology
Dr. Holman combines label-free spectromicroscopy with spatial *omics technologies to characterize and understand biological and experimental model systems. His goal is to investigate disease-relevant tissue microenvironments and architectures that can be used to develop imaging probes and therapies.
Staff
Michael J. Mandella, PhD
Optical Scientist
Dr. Mandella's work at Stanford began in 2004 when he worked as a research scientist at Stanford's School of Medicine. He was based in the Clark Center (Bio-X Program) and worked in the labs of Dr. Chris Contag, Dr. Sam Gambhir, Dr. Gordon Kino, and Dr. Olav Solgaard, where he spearheaded the development of the Dual-Axis Confocal Scanning Microscope. This was a new way to design and build high-resolution microscopes which could be miniaturized using Silicon-based scanning micro-mirrors (MEMS) made at Stanford's Nanofabrication Facility. These new miniaturized microscopes were used in preclinical and clinical experiments in the development of endoscopic molecular imaging applications such as early-stage colon cancer detection and fluorescence-guided surgery.
Starting in 2017, Dr. Mandella held a professor on call position in the Department of Biomedical Engineering at Michigan State University (MSU) with a primary role to provide the optics expertise within various multidisciplinary research groups in MSU's Institute for Quantitative Health Science and Engineering. While at MSU, he designed and built a variety of molecular imaging optical instruments for imaging and analyzing various types of biological specimens.
Dr. Mandella then returned to Stanford to provide optical science and engineering support in the Rogalla Lab on projects involving fluorescence-guided endoscopy and spectroscopic-guided endoscopy.
Alexa Weingarden, MD, PhD
Basic Life Research Scientist
Dr. Weingarden's work focuses on generating regulatory T cells as a potential therapeutic for inflammatory bowel disease by engineering individual members of the gut microbiome. Dr. Weingarden is also interested in understanding differences in mucosal adaptive immunity and interactions with the gut microbial community across different subtypes of IBD.
Medical Fellows and Postdoctoral Scholars
Andrew Li, MD
Advanced Endoscopy Fellow in Gastroenterology & Hepatology
Dr. Li's clinical and research interests are in gastric cancer, advanced endoscopy, and the application systems biology and artificial intelligence in gastroenterology.
Steven Levitte, MD, PhD
Postdoctoral Medical Fellow in Pediatric Gastroenterology and Hepatology
Intestinal strictures remain a common and debilitating complication of Crohn’s disease that frequently require surgical bowel resection. Even in patients who undergo successful stricture resection, recurrent fibrostenotic disease remains common. While some immune pathways have recently been implicated in stricture formation, the molecular and cellular mediators of fibrosis remain elusive. Studying intestinal fibrosis is difficult because endoscopic biopsies can miss mediators of intestinal strictures which form deep within the bowel wall. To address this, Dr. Levitte uses quantitative imaging techniques to identify mucosal and submucosal mediators of intestinal fibrosis, and identify alterations in immune cell subsets associated with stricture recurrence.
Pradeep Siddappa, MD
Advanced Endoscopy Fellow in Gastroenterology & Hepatology
Dr. Siddappa is a gastroenterology and hepatology fellow at Stanford University. His academic interests include pancreatology and advanced endoscopy. Dr. Siddappa wants to combine his passion for advanced endoscopy with translational research toward the goal of early detection of pancreatic cancer. His current research projects involve in-vivo optical imaging for the detection of GI pancreatic cancer, pancreatic cyst fluid proteomics, and GI cancer genomics. When he is not working, Dr. Siddappa loves to read about history, culture, and religion.
Sonia Ferkel, MD
Postdoctoral Scholar
After completing her medical studies at the University Medical Center Göttingen and her basic science training at the Max Planck Institute for Multidisciplinary Sciences in Göttingen, Dr. Ferkel joined the Rogalla lab to study gastrointestinal malignancies. With Dr. Rogalla, she is investigating immuno-oncological interactions and working to identify prognostic biomarkers and molecular targets to be addressed by novel imaging techniques and translated into precision medicine. As a budding oncologist and physician scientist, she is committed to improving the quality of life and overall survival of patients with cancer.
Elizabeth Holman, PhD
Postdoctoral Scholar
After completing her graduate studies at Caltech which focused on applying infrared spectroscopy to studying live organisms, Dr. Holman joined the Rogalla lab to explore how her experience in vibrational spectroscopy can be applied practically in the clinical and research medical sciences. Her direct research interests relating to biomedical imaging include vibrational spectroscopy, machine learning, and spatial biology techniques such as CODEX.
Lisanne Neijenhuis, MD
Postdoctoral Scholar
After obtaining her MD degree at Erasmus University in Rotterdam, in the Netherlands, Dr. Neijenhuis worked as a doctor at the surgical department for a year. Hereafter, she started at the Green Light Leiden research group under Dr. Alexander Vahrmeijer at the Leiden University Medical Center. This research group focuses on image-guided surgery and is expertized in the clinical translation within this research field. As part of a collaboration between Leiden and Stanford, Dr. Neijenhuis came here as a postdoc to work on a clinical trial involving fluorescence-guided endoscopy in rectal cancer. Her ultimate research goal is to prolong cancer survival while improving quality of life. Dr. Neijenhuis' academic interests include fluorescence-guided surgery, fluorescence imaging, surgical oncology, colorectal cancer and active surveillance. Outside work she likes to hike, ski, mountain bike and to photograph.
Medical Residents
Yoni Samuel Rubin, PhD, MD
Internal Medicine Resident
Dr. Rubin's research interests are to better understand the molecular and cellular mechanisms underlying chronic immune-mediated diseases such as IBD and leverage this knowledge to develop safer, cheaper, and more effective tools for detecting and treating illnesses worldwide.
Assistant Clinical Research Coordinators and Research Associates
Raoul Samuel Sojwal, BA in Neuroscience
Assistant Clinical Research Coordinator
