A new discovery which slows the spread of human cytomegalovirus could improve treatment, according to the researchers who made it.
They said the widespread virus was hard to treat because it could evade the immune system. But they developed a new type of antibody with a modified structure that they claim can outsmart the virus and neutralise its ability to evade the immune system.
The new antibody design blocks cytomegalovirus from hiding from the immune system which they hope will lead to safer, more effective treatments for vulnerable patients.
Cytomegalovirus (CMV) is the most infectious cause of birth defects and the leading infectious cause of disability in Australia. It can cause permanent hearing loss, blindness, neurodevelopmental disability, physical and intellectual disabilities and cerebral palsy.
The Kids Research Institute Australia said about 3,000 Australian newborn babies contract congenital cytomegalovirus each year, with about 10% (300 babies) developing permanent disabilities such as hearing loss, vision impairment, or developmental issues.
Scientists and engineers from the University of Texas (Texas Biologics), the University of Freiburg and Cardiff University reported their findings in Cell Reports on 23 December 2025.
“Our engineered antibodies are like a lock that the virus can’t pick,” said one of the lead authors, Professor Jennifer Maynard from the Cockrell School of Engineering’s McKetta Department of Chemical Engineering.
“They retain their ability to activate the immune system but are no longer vulnerable to the virus’s tricks.”
Despite its prevalence, there is no vaccine. Current treatments rely on antiviral drugs that can have toxic side effects and lead to drug resistance, creating an urgent need for safer and more effective therapies, the researchers said.
Significantly reduced spread
In experiments, the antibody prevented the virus from spreading between cells, a key feature that makes CMV so hard to control
The antibodies significantly reduced viral dissemination in infected cell cultures, showing the ability to slow the spread of the virus.​
“It’s like a tug-of-war between the virus and the immune system,” said Dr Ahlam Qerqez, lead author of the study and senior scientist at Denali Therapeutics.
“The virus has evolved clever strategies to pull antibodies away from their intended targets, making it harder for the immune system to do its job.”​
The virus produces proteins –viral Fc receptors (vFcγRs) that interfere with the body’s natural defense mechanisms.​
The proteins bind to antibodies – immune system molecules that normally help fight infections – and prevent them from activating immune cells such as natural killer (NK) cells, he said.
NK cells are responsible for clearing out infected cells, but HCMV’s vFcγRs essentially “hijack” antibodies, rendering them ineffective, he added.
The engineered antibodies are designed to avoid HCMV’s vFcγRs while still activating NK cells to attack infected cells. ​
The team focused on a specific type of antibody called IgG1, which plays a key role in fighting infections.​ By studying how HCMV interacts with IgG1, the researchers identified the exact regions of the antibody that the virus targets and altered them to prevent the virus from binding.
“This work represents a paradigm shift in how we think about antiviral therapies,” said Professor Jason McLellan from the College of Natural Sciences’ Department of Molecular Biosciences at UT and co-author of the paper.
“Instead of just trying to neutralise the virus, we’re focusing on empowering the immune system to clear infected cells.​ It’s a more holistic approach that could lead to better patient outcomes.”
The engineered proteins will require several more rounds of testing before they can be used in clinical settings.​ The team is also investigating combining their approach with other therapies, such as antiviral drugs or vaccines, to create a comprehensive treatment strategy.
The virus spreads from person to person through body fluids and like all herpesviruses such chicken pox, it stays in the body for life after infection.
The US Centers for Disease Control and Prevention said the virus was the most infectious cause of birth defects in the United States.
