A team of researchers from Monash University and the Lions Eye Institute has identified a tissue protein that plays a crucial role in regulating immune cell movements, which can be exploited by the cytomegalovirus (CMV) to undermine immune responses. Their study, published in the journal Nature, reveals how a molecule known as CD44 orchestrates the activities of immune cells, ultimately affecting the body’s ability to fend off infections and respond to vaccinations.
The research highlights the importance of stromal cells—support cells that facilitate communication and movement among immune cells. These stromal cells are essential for maintaining the efficiency of the immune system. The study’s findings indicate that CMV can disrupt this system by producing a protein that inhibits the function of CD44 on stromal cells, essentially derailing the traffic of immune cells and weakening the body’s antiviral response.
Significance of CD44 in Immune Regulation
Lead researcher Professor Mariapia Degli-Esposti, who serves as the Head of Experimental and Viral Immunology at the Monash Biomedicine Discovery Institute and the Lions Eye Institute, emphasized the transformative nature of these findings for understanding immune mechanisms. “Think of the immune system like a busy city with millions of cells patrolling to keep us safe,” she explained. “CD44 acts as the central traffic controller; it keeps immune cells moving and coordinates their interactions at the right place and time.”
This discovery marks a significant shift in how scientists comprehend the dynamics of immune function. As Professor Degli-Esposti noted, “Our study identifies CD44 as a master regulator of immune cell movement and communication. It shows that viruses can undermine immunity not only by attacking immune cells directly but also by targeting the essential tissue infrastructure they rely on.”
Potential Implications for Treatment
Co-lead researcher Dr. Chris Andoniou, a Senior Research Fellow at both Monash and the Lions Eye Institute, discussed the broader health implications of the findings. “Because CD44 plays such a central role in regulating immune activity, drugs inspired by the viral protein identified in this study could be developed to precisely dampen harmful inflammation,” he said.
The potential to learn from the virus opens up avenues for creating therapeutic molecules designed to safely reduce excessive immune activation. This could eventually lead to improved management and treatment strategies for various autoimmune conditions. “We are still in the early stages, but this is an exciting development,” Dr. Andoniou added.
The study, titled “Fibroblastic reticular cells direct initiation of T cell responses via CD44,” is set to be published in Nature in 2026. The findings underscore the intricate relationship between viruses and the immune system, paving the way for future research into innovative treatment options.
