Researchers at the University of Rochester Medical Center have made significant strides in identifying a protein that could revolutionize the diagnosis and treatment of severe bone infections caused by Staphylococcus aureus. In a study published on November 12, 2025, in the journal mBio, the team focused on a small protein known as CCL20, which may serve as a vital indicator in managing these infections, particularly osteomyelitis.
Osteomyelitis, a bone infection, poses serious health risks, including septic shock and potential death. Despite ongoing efforts to improve early detection and treatment, progress has lagged. The latest findings suggest that CCL20 plays a crucial role in the immune response to staph infections. Researchers observed a steady rise in CCL20 levels following infection in mouse models, indicating its involvement in the body’s defense mechanisms.
Identifying CCL20 as a Diagnostic Tool
The study revealed that CCL20 levels were significantly elevated in patients who developed bone infections after undergoing hip or knee replacements. While healthy individuals showed normal CCL20 levels, those with infections exhibited a fivefold increase, with levels soaring to 100 times normal in patients who succumbed to sepsis. This pattern suggests that CCL20 acts as an SOS signal to the immune system, providing a potential avenue for a simple blood test that could predict the severity of an infection.
Gowrishankar Muthukrishnan, Ph.D., an assistant professor in Orthopedics and Microbiology & Immunology at the University of Rochester, noted the urgency of rapid treatment for staph infections. “Treating a staph infection quickly offers patients the best chance at recovery and can prevent the risk of sepsis, which can cause death in a matter of hours,” he stated. The findings underscore the importance of developing accessible diagnostic tools to enhance patient outcomes.
Addressing a Growing Health Concern
Approximately 2 million total joint replacements are performed annually in the United States, with osteomyelitis emerging as a serious post-operative complication. Although infections remain relatively rare, their consequences can be severe, often requiring extensive antibiotic treatments and sometimes leading to further surgeries. The projected increase in joint replacement surgeries, coupled with an aging population, suggests that the number of prosthetic joint infections may reach up to 200,000 annually by 2030, resulting in healthcare costs that could soar to $3 billion each year.
First author Himanshu Meghwani, Ph.D., highlighted the potential of CCL20 not only as a diagnostic marker but also as a therapeutic target. Its ability to attract immune cells to infection sites may enhance the body’s natural defenses. Nonetheless, the research team acknowledges that further investigation is necessary, as some patients with elevated CCL20 levels still face difficulties in overcoming infections.
The findings from this study represent a critical advancement in the understanding of bone infections and the immune response. As research progresses, there is hope that CCL20 could pave the way for improved diagnostic and treatment strategies, ultimately reducing the burden of bone infections on patients and healthcare systems alike.