Mount Sinai Study Reveals Genetic and Cellular Mechanisms of Crohn’s Disease
New study identifies a novel approach for tailored treatment that could be more effective for patients with the chronic disease
Mount Sinai researchers have identified genetic and cellular mechanisms of Crohn’s disease, providing new insights for future treatments that could offer a tailored approach to patients with the chronic inflammatory disease, according to a study published in Nature on March 31.
The researchers found that blocking the common cytokine receptor subunit gp130 may benefit some patients with Crohn’s disease and could complement a standard treatment for moderate to severe Crohn’s disease known as anti-tumor necrosis factor (TNF) treatment. This treatment uses medications known as TNF inhibitors to block white blood cells producing the protein TNF, which causes the inflammation.
Crohn’s disease is a chronic inflammatory intestinal disease with frequent abnormal healing and complications that narrow or constrict passage through the digestive tract. Complications associated with Crohn’s disease are driven by communication between cells called macrophages that detect and destroy harmful bacteria or organisms, and cells known as fibroblasts that aid with wound healing. Mount Sinai researchers analyzed inflamed and normal tissues of the small intestine in humans, and zebrafish models of intestinal injury, and showed that a dysregulated macrophage-fibroblast niche can be driven by Crohn’s disease-associated mutations in the gene NOD2.
These findings are reported on the 20th anniversary of the discovery by Judy H. Cho, MD, Dean of Translational Genetics and Director of The Charles Bronfman Institute for Personalized Medicine at the Icahn School of Medicine at Mount Sinai, her colleagues, and others that genetic variants that cause the protein produced by NOD2 to lose function are associated with increased risk for Crohn’s disease. NOD2 recognizes bacterial components, and the intestinal immune system is exposed to high bacterial concentrations in both healthy and diseased states. However, the reasons why mutations in NOD2 cause increased risk for Crohn’s disease and why some patients do not respond to anti-TNF medications remained incompletely defined until now. Patients carrying NOD2 mutations have increased activated fibroblast and macrophage gene expression, and in particular, elevated gp130-related gene expression. Given this finding, the researchers believe that blocking the protein gp130 may help patients who are nonresponsive to the treatment of anti-TNF medications.
“Our work defines a completely new mechanism whereby NOD2 mutations confer risk, namely through altered differentiation of newly recruited blood monocytes over time,” says Dr. Cho. “It sharpens current research efforts involved in serial tissue and blood analyses to define how non-response or loss-of-response to anti-TNF therapies may be improved.”
Shikha Nayar, the study’s first author and a PhD candidate in Dr. Cho’s lab at Icahn Mount Sinai, said the findings could provide a more custom-made approach to future patient care. “We’ve developed novel in vivo and in vitro models to define mechanisms and timing of disease progression,” she says. “These studies may help tailor treatments more effectively for Crohn’s disease patients carrying NOD2 mutations and elevated signatures we have described.”
The Department of Pediatric Gastroenterology at Emory University contributed to the study. This work was also supported by National Institutes of Health (NIH) grants R01 DK106593, R01 DK123758-01, U01 DK062422 (to J.H.C.).
About the Mount Sinai Health System
The Mount Sinai Health System is New York City's largest academic medical system, encompassing eight hospitals, a leading medical school, and a vast network of ambulatory practices throughout the greater New York region. Mount Sinai advances medicine and health through unrivaled education and translational research and discovery to deliver care that is the safest, highest-quality, most accessible and equitable, and the best value of any health system in the nation. The Health System includes approximately 7,300 primary and specialty care physicians; 13 joint-venture ambulatory surgery centers; more than 415 ambulatory practices throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and more than 30 affiliated community health centers. The Mount Sinai Hospital is ranked on U.S. News & World Report's "Honor Roll" of the top 20 U.S. hospitals and is top in the nation by specialty: No. 1 in Geriatrics and top 20 in Cardiology/Heart Surgery, Diabetes/Endocrinology, Gastroenterology/GI Surgery, Neurology/Neurosurgery, Orthopedics, Pulmonology/Lung Surgery, Rehabilitation, and Urology. New York Eye and Ear Infirmary of Mount Sinai is ranked No. 12 in Ophthalmology. Mount Sinai Kravis Children's Hospital is ranked in U.S. News & World Report’s “Best Children’s Hospitals” among the country’s best in four out of 10 pediatric specialties. The Icahn School of Medicine is one of three medical schools that have earned distinction by multiple indicators: ranked in the top 20 by U.S. News & World Report's "Best Medical Schools," aligned with a U.S. News & World Report "Honor Roll" Hospital, and No. 14 in the nation for National Institutes of Health funding. Newsweek’s “The World’s Best Smart Hospitals” ranks The Mount Sinai Hospital as No. 1 in New York and in the top five globally, and Mount Sinai Morningside in the top 20 globally.