Chronic inflammatory bowel disease (IBD) presents a significant clinical challenge, characterized by a persistent and unpredictable course that often leads to severe complications, including an elevated risk of bowel cancer. The burden of these conditions is particularly heavy on younger populations. When genetic predispositions intersect with specific environmental triggers, diseases such as ulcerative colitis and Crohn’s disease typically manifest between the ages of 15 and 29—a developmental window that coincides with the critical years of education and the beginning of a professional career. Given the lifelong implications of these diagnoses, prompt and effective clinical intervention is essential. Researchers at Charité – Universitätsmedizin Berlin have now identified a specific therapeutic target that plays a critical role in halting these ongoing inflammatory processes. Their findings, which offer a promising path toward more effective treatments, have been published in the current issue of the journal Nature Immunology.
The onset of these conditions is often deceptive, beginning either gradually or in sudden, acute flare-ups. Patients frequently describe a constellation of debilitating symptoms: severe abdominal cramps, chronic diarrhea, significant weight loss, persistent fatigue, and an immense level of emotional distress. These two primary forms of IBD, Crohn’s disease and ulcerative colitis, are distinct in their presentation and impact. While ulcerative colitis is generally confined to the inner lining of the large intestine, Crohn’s disease is more systemic, capable of involving the entire thickness of the intestinal wall. While it most commonly affects the small intestine, it can also manifest in the stomach and esophagus. Beyond the immediate physical pain, the chronic nature of the inflammation causes lasting tissue damage, which, over time, significantly increases the risk of malignancy.
Current standard treatments largely rely on systemic immunosuppression—a broad-spectrum approach that dampens the immune system as a whole. While effective for many, this strategy can leave patients vulnerable to other infections and does not address the specific root causes of the inflammation. The medical community has been moving toward more precise, targeted therapies that aim to interrupt the inflammatory cascade by blocking specific messenger substances that drive the immune response. Despite these advancements, many patients remain resistant to existing therapies, necessitating a deeper understanding of the molecular mechanisms driving these diseases.
The etiology of severe systemic inflammatory diseases remains one of the most complex puzzles in modern gastroenterology. It is widely accepted that both genetic factors and environmental influences contribute to their development, yet the precise interplay remains elusive. For several years, Professor Ahmed Hegazy of Charité’s Department of Gastroenterology, Infectiology, and Rheumatology has dedicated his research to unraveling these inflammatory processes and the body’s defense mechanisms. Together with his research team, he has now succeeded in identifying the interaction between two specific immune system messenger substances as the primary driving force behind chronic intestinal inflammation.
The two proteins at the center of this discovery are Interleukin-22, which generally serves a protective function by supporting the cells lining the gut and maintaining the protective mucosal barrier, and oncostatin M, a signaling molecule traditionally associated with tissue repair and cell differentiation.
An Uncontrolled Chain Reaction
"At the clinic, we are primarily seeing young patients who are just beginning their professional lives," Professor Hegazy explains. "Up until now, we have largely been limited to slowing down the progression of the disease and alleviating the most severe symptoms. However, not all patients respond well to existing therapies, and there is an urgent, unmet need for new, more effective therapeutic approaches."
In previous investigations, the research team closely examined the role of oncostatin M, identifying it as a potent, inflammation-promoting messenger molecule. Produced by specific immune cells, this protein acts as a catalyst, activating other inflammatory factors and initiating a destructive chain reaction that triggers an excessive immune response. According to Professor Hegazy, the clinical implications of this protein are significant. "It was especially interesting for us to see that patients with high levels of oncostatin M often do not respond to several of the most common therapies currently in use," he says. "This suggests that oncostatin M levels could serve as a valuable biomarker, helping us predict treatment failure and identify patients who are likely to experience a more severe disease course. This is precisely where we focused our efforts; we wanted to understand this signaling pathway in greater detail to find ways to block it with targeted, novel treatments."
Over the course of five years, the research team worked to uncover the exact mechanism by which oncostatin M triggers inflammatory responses. They employed a multi-faceted approach, beginning with animal models and progressing to the analysis of human tissue samples to observe the different stages of chronic intestinal disease. Using state-of-the-art single-cell sequencing, the researchers were able to compare inflamed gut tissue with healthy tissue, revealing that a much larger number of unexpected cell types in the inflamed gut possess binding sites, or receptors, for oncostatin M. Simultaneously, the researchers observed that additional immune cells began producing the inflammatory protein.
The role of Interleukin-22 proved to be particularly surprising. While it is known for its role in tissue protection, the team found that in the context of chronic inflammation, it actually makes the gut lining more sensitive to oncostatin M by increasing the density of its receptors. "These two immune messengers work in concert to amplify the inflammation, drawing more and more immune cells into the intestine," Professor Hegazy relates. "It is much like a fire that keeps receiving more fuel, causing it to spread uncontrollably. In our experimental models, we specifically blocked the binding sites for oncostatin M and observed a clear, marked reduction in both chronic inflammation and the associated risk of cancer."
Targeted Therapy for High-Risk Patients in Sight
The team’s analysis of tissue samples from patients with colorectal cancer caused by chronic intestinal inflammation revealed a notably high concentration of oncostatin M receptors surrounding the tumors—a phenomenon not observed in the surrounding healthy tissue. This discovery provides strong evidence that this specific signaling pathway is an active contributor to the development of malignancy.
However, the researchers emphasize that chronic inflammation does not automatically lead to cancer, nor does it affect every patient in the same way. "Chronic inflammatory bowel diseases are highly complex and differ significantly from person to person," notes Professor Britta Siegmund, Director of the Clinic for Gastroenterology, Infectiology, and Rheumatology at Charité. "That individual variability is exactly what makes these diseases so notoriously difficult to treat and predict. Thanks to the identification of the amplifying interaction between oncostatin M and Interleukin-22, we now have a much clearer understanding of the driving forces behind the inflammation in a subset of patients. This opens the door to developing and testing a completely new class of therapeutic approaches."
The team’s experimental findings have moved quickly toward potential real-world applications. By specifically disrupting the harmful synergy between Interleukin-22 and oncostatin M, researchers believe they can intervene in the disease process far more effectively than current systemic methods allow. "Our results provide a robust scientific basis for developing targeted treatments against this specific inflammation-promoting mechanism, particularly for patients who suffer from the most severe and treatment-resistant forms of the illness," Professor Hegazy concludes.
The progress from laboratory discovery to clinical application is already underway, with a clinical trial currently testing an antibody designed to block the receptors for oncostatin M. As the research continues, the medical community remains optimistic that these insights will eventually provide patients with a path toward better management of their condition, improved quality of life, and a reduced risk of long-term complications. By focusing on the molecular drivers of the disease, the researchers at Charité are moving closer to a future where IBD can be treated with the precision and efficacy that young patients need to pursue their lives without the constant shadow of chronic illness.
