Research Areas

Dr. Abreu’s laboratory conducts both basic science and clinical/translational research to elucidate the causes and consequences of inflammatory bowel diseases and colitis-associated colon cancer.

As clinicians and scientists, we recognize that patient care is not a “one-size-fits-all” approach. Each individual has unique genetics and a unique microbiome. Therefore, we seek to design personalized approaches to treatment so that we can deliver precision medicine. Our laboratory has developed one of the richest biobanks of data and samples from our patients with IBD. We have used these samples to identify the immune pathways driving inflammation in the intestine. We have also pioneered studies to optimize the dose of biologic therapies so that patients reap the most benefit from these medications while experiencing minimal side effects.

Studies have revealed that the gut microbiome (the collection of microorganisms that live in our digestive tract) can influence health and disease. We have focused on interactions between the human host and these gut microbes, including how the gut recognizes and responds to specific (harmful) bacteria, bacterial characteristics that increase their virulence, the human innate immune system, and underlying genetic factors that enhance susceptibility to disease. IBD is driven by the gut microbiota, yet the specific pathobionts (disease-causing microorganisms) leading to the development of IBD have been elusive. Certain pathobionts may be able to cross the lining of the intestine and take up residence within intestinal immune cells. Indeed, the Abreu Lab performed deep RNA sequencing and revealed the presence of live pathobionts, such as E. coli, inside the immune cells of IBD patients. The pathobionts displayed several characteristics that increased their harmful nature, such as antimicrobial resistance. We hypothesize that these pathobionts trigger inflammation in IBD patients. Our findings highlight our position in the vanguard of high-tech IBD research and suggest targets for future therapies.

Severe cases of colitis result in a 10-times higher risk of colon cancer among patients with IBD. Moreover, when physicians find pre-cancerous lesions in these patients, the next step is to remove the colon because we lack good methods of preventing progression from inflammation to abnormal or pre-cancerous growth (dysplasia) and cancer. The Abreu Lab has made great strides in advancing the study of colitis-associated colon cancer. We were the first to report that the innate immune system in the intestines is essential to cancer development because of its abnormal responses to gut bacteria. More recently, we discovered that the cells lining the colon in patients with IBD are constantly producing hydrogen peroxide in an attempt to protect themselves from abnormal bacteria. The local production of hydrogen peroxide, along with these abnormal bacteria, promotes the development of colon cancer. 

Our team is currently working on several strategies that can be used to halt the progression of ulcerative colitis from inflammation to colon cancer. We aim to identify specific microbial pathways and drugs that can inhibit production of hydrogen peroxide by these colon-lining epithelial cells. Our research is foundational for the development of interventions to shield patients with IBD from the risk of colon cancer.

Dr. Abreu has made landmark contributions to the field of IBD. Her translational work on therapeutic drug monitoring and genetic variation in drug response genes has also fundamentally altered biologic therapy, enabling precision medicine for IBD. Specifically, her research group has called attention to the growing number of IBD cases among immigrants from Latin America. IBD genetics research has previously been conducted with European-ancestry individuals. Through compiling the country’s largest biorepository of samples from Hispanic patients, Dr. Abreu’s team has revolutionized our understanding of complex genetic disorders, highlighting the importance of considering ancestral origins (e.g., Amerindian, African or European) and defining the genotype-phenotype relationship of the most important susceptibility gene for Crohn’s disease (Nod2).

Researchers have linked diet to the development of IBD and to the quality of life of patients with IBD. Despite widespread belief among patients that eating certain foods can trigger flares of disease activity, the specific triggers remain unknown—as do the foods that can help patients manage their symptoms. Given the intersecting importance of diet, genetics, and the gut microbiota, exploring dietary patterns that reduce inflammation and alleviate symptoms in CD and UC patients is a promising avenue for future research. 

Dr. Abreu’s lab is currently investigating the benefits of a low-fat, high-fiber diet for disease management as a way to empower IBD patients to make their own health decisions, minimizing their symptoms, reducing their uncertainty about food choices, and increasing their ability to eat healthy fruits and vegetables. The team is also exploring methods to help patients successfully change their diet to reduce symptoms and maintain these changes over the long term.