The Croitoru Lab is fully committed to a culture of belonging and an inclusive environment that attracts and retains a diverse workforce, at all levels of the organization that reflects the communities we serve. We welcome applications from racialized person, women, Indigenous persons, persons with disabilities, 2SLGBTQ+ persons, and those from diverse backgrounds and experiences.

Dr. Kenneth Croitoru joined the Division of Gastroenterology at Mount Sinai Hospital in January 2008. He completed medical school at McGill University in 1981 and then trained in internal medicine and gastroenterology from 1982-1986. He went on to do post-doctoral training as an MRC Research Fellow in Mucosal Immunology with Dr. John Bienenstock at McMaster University.


Harden is the Database Manager for Dr. Croitoru’s GEM Project database. He joined on to the program in 2016 He is responsible for data management, queries and quality assurance of the information entered by all of the sites.

Williams has a strong interest in the field of microbiota and its impact on human health. While completing a PhD in biotechnology and microbiology in France, he examined the probiotic and nutritional potential of lactic acid bacteria present in the microbiota of a fermented cereal based food using a molecular approach. At the University of Toronto and Samuel Lunenfeld Research Institute, he is currently investigating the effect of environmental factors and genotypes on human microbiome composition in the context of the prospective cohort Genetic, Environmental Microbial (GEM) project. His projects involve multiple skills and knowledge of various scientific fields, including advanced biostatistics, human physiology, human genetics, human microbiome, and human nutrition. His main project focuses on the effect of human genetics on microbiome composition and function.

Sun-Ho is a certified Gastroenterologist MD who previously completed his GI fellowship at Asan Medical Center, South Korea. He came to Toronto to start an Advanced IBD fellowship at Mount Sinai Hospital in July 2018. His main interest is translational research in IBD. At the Croitoru lab, he has been part of the GEM project to investigate the pre-clinical state of Crohn’s disease. He has decided to pursue a PhD degree at the Institute of Medical Science, University of Toronto, under supervision of Dr. Croitoru, since January 2019 with the focus of understanding the pre-disease interaction of host genetics, gut microbiome, anti-microbial immune response, gut barrier function and subclinical inflammation as a window into the pathogenesis of Crohn’s disease. He is applying machine-learning approaches to develop an integrative multi-omics prediction model to identify individuals at higher risk of developing Crohn’s disease and to determine the key contributing microbial and metabolomic factors to CD pathogenesis.  


PhD student, Department of Immunology
BSc Microbiology and Immunology, Western University
Exploring the role of diet in early life on gut microbiome and immune development, including in the context of inflammatory bowel disease risk factors.

Mingyue Xue joined the Croitoru lab as a post-doctoral research fellow in 2021 after completing a PhD in Clinical Data Science in China. Her current project is part of the GEM project to investigate the pre-clinical state of Crohn’s disease. Specifically, she is developing machine learning and/or statistical approaches for multi-omics data structures to predict individuals’ risk of developing Crohn’s disease and uncover possible triggers of Crohn’s disease. She wants to collaborate with team members from different majors to improve the ability to prevent the disease from taking hold in the first place.

Heather MacAulay joined the GEM Project team as a Research Assistant in 2016. She has since taken on various roles such as a Research Coordinator, Project Assistant and is currently the Project Manager for the GEM Project. In addition, she also manages other translational research studies and trials led by Dr. Ken Croitoru. She has completed an HBSc in Nutrition and Dietetics from Western University, and an HBSc in Human Kinetics from the University of Guelph.

Tashina Ahsan joined the team in 2021. She has a BSc degree in Microbiology and a post-graduate diploma in Project Management. She is a qualified Medical Laboratory Technician and is a certified member of the CSMLS and MLPAO. Tashina performs sample collection and processing duties in the laboratory as well as recruitment for the IMAGINE, PRECIOUS and PIONIR studies.  

Nicole Kayrala joined the Croitoru lab as a Research Assistant. She is primarily working on the GEM (Genetics Environment and Microbiology) project. The GEM project is an international research study that aims to determine possible causes for Crohn’s Disease. Additionally, she is assisting in recruitment and specimen collection for the IMAGINE project. Assisting in determining the health outcomes for those with IBD is important to her because Canadians experience the highest rates of IBD in the world, affecting 1 in 150 Canadians. She is passionate about creating better health outcomes for those whose lives are riddled with uncertainty and perturbed by ulcerative colitis or Crohn’s disease. In 2021, she earned an Honours BSc in Biomedical science, minoring in neuroscience from the University of Ottawa

Larbi is interested in the microbiological changes that may trigger diseases in human and animals, with a focus on the interaction between host and microbiome. As a postdoctoral fellow in the Croitoru lab, he is exploring the factors that may trigger Crohn’s disease in genetically susceptible individuals. This is made possible by mining the outstanding GEM project database, which includes data on first degree relatives (FDRs) of Crohn’s disease patients. Currently, his primary focus is on studying the interaction between FDRs genetics and their microbiome using a large bioinformatics and statistical toolset.

Alireza Tavakoli has joined Dr. Croitoru’s clinical research team at Mount Sinai Hospital’s Lunenfeld-Tanenbaum Research Institute. Alireza will be assisting with the GEM project and coordinating patient recruitments and data collection for the IMAGINE and other research projects. Alireza has obtained his HBSc in Biomedical Science from York University, and his interests are in medicine and clinical research.

Cristina currently works for the GEM Project, an international research study attempting to determine possible causes for Crohn’s Disease. She began working on the project as a summer student in 2014 and returned in August 2015 as a research assistant. Her duties include reviewing the health status of individuals enrolled in the GEM Project, supporting affiliate sites across the world and general study administration. She previously obtained a BA in Biology from Williams College and a MSc in Biomedical Sciences from Tufts University.

Anna Neustaeter is a postdoctoral researcher within the Crohn’s Colitis Canada – Genes, Environment, Microbiome project, currently utilizing cohort-derived data on nutritional and biological aspects to Crohn’s disease risk. She received her MSc in animal genomics at the University of Guelph, where she performed genomic and in silico analyses of a complex adult-onset neuromuscular disorder in milk-producing cattle. Her PhD project ‘Towards Genetic Screening for Glaucoma’ was supervised by Prof. Nomdo Jansonius (head of Ophthalmology) and Prof. Harold Snieder (head of Genetic Epidemiology) at the University Medical Center, Groningen, in the Netherlands. She utilized cohort-derived biological data in creating data-driven strategies for genetic pre-screening for glaucoma, as well as improving upon self-reported glaucoma status by incorporating subjective visual experiences for questionnaire-based data. Her research interest lies in genetic and epidemiological analyses of complex disorders.

Grace joined the team in 2015 as a clinical research coordinator for both Dr. Silverberg and Dr. Croitoru. She is involved in patient recruitment, collecting biological samples and questionnaire data entry. Her favourite part of the job is interacting with patients and listening to their stories. In her spare time, Grace enjoys sleeping, baking and spending time with friends and family.

My name is Nisha Ganeswaren and I have completed my Honours Bachelor of Science from the University of Toronto pursuing a double major in Health Studies and Biochemistry. Since July 2015, I have been working as part of the Global Project Office for the GEM Project. As part of the GEM Team, we are actively involved in ensuring that study procedures are adhered at all times. Furthermore, we are actively involved in providing support to the study sites based across the world.

I am interested in the dynamic host-microbiota relationship. We cannot live without our microbes and our immune system works to distinguish symbiotic friend from pathogenic foe. How this happens, we are yet to understand. We have barely scratched the surface of understanding the complex bidirectional dependence between a host and their microbes.

My research is focused on understanding how perturbing the microbiota at different times can influence the mucosal immune system, and how this can lead to an altered susceptibility to colitis. I am interested in how the perturbation alters the bacterial community composition, the resilience of the community and how the immune system responds to the changing microbiota.

Mitra has been with Dr. Croitoru’s group since June 2011. She is currently working at the Central Processing Lab for the GEM Project at the University of Toronto. She is responsible for the preliminary processing and also managing and storing of all of the biospecimens collected by the study coordinators from sites worldwide.

MSc, Cell and Systems Biology
University of Toronto, 2013
BSc, Cellular and Molecular Biology
University of Ottawa, 2009

The relationship between our health and microbial inhabitants is poorly understood and likely to be vast in its implications with Inflammatory Bowel Disease (IBD). IBD is used to collectively describe two distinct gastrointestinal tract diseases, Crohn’s Disease and Ulcerative Colitis. We are concerned in identifying biomarkers and developing new approaches for predicting, diagnosing and treating those with Crohn’s disease. We hope these biomarkers could be applied in a noninvasive manner to improve the lives of these patients.

Currently, I am comparing the status of potential biomarkers of the gut and blood in healthy versus diseased host states. The approaches I use include immune cell phenotyping by flow cytometry on innate and adaptive immune peripheral monocytes. I am assessing T-cells driving or regulating the immune response in chronic inflammatory states, and associated intracellular markers (IL-17a, TNF, and IFNg). Furthermore, we are interested in a unique innate T-cell subset, MAIT cells, which have been shown to be present in mucosal T-cells and react to microbial derived products.

Kirtana joined the GEM Project team in 2020. She is responsible in supporting various research projects aiming to learn more about IBD and conducting health reviews with study participants.

Carmen recently joined the group in 2016. She is working on the GEM and GEMINI project at the University of Toronto for Dr.Croitoru. She is responsible for sample processing, and carrying out in vitro and in vivo experiments with samples obtained from human studies.

Post-Doctoral Research Fellow
PhD in Immunology, University of Alberta.
Project: Characterizing T cell responses to gut microbial antigens in IBD murine models.