engineered phages – In a mouse study, scientists used a harmless phage engineered to home in on tumor cells and redirect malaria vaccine–built immunity against cancer. In nearly half of the treated animals, tumors were eradicated and did not return a year later. Researchers are n
For many people, immunotherapy has become a lifeline. For many others, it still doesn’t land. The hard part is teaching the immune system to spot cancer as a threat—before the body learns to treat tumors as something to ignore.
A new approach aims to solve that problem by borrowing the immune system’s own memory. Bacteria-killing viruses called phages have already cleared cancer cells in mice by redirecting immunity built up from vaccinations. In the study. vaccinating mice against malaria and then using a harmless phage to redirect that immune response toward cancer cells led to tumors being eradicated in nearly half of the animals.
The work started with a question that sounds simple until you try to make it real: what if the immune system could be steered, not just activated?
Amin Hajitou at Imperial College London and his colleagues focused on a phage that usually infects Escherichia coli. After the phage attaches to these bacteria and injects its genetic material. it hijacks their genetic machinery to produce thousands of new phages. then destroys the bacteria. In this case, the researchers didn’t want it to attack E. coli at all—they wanted it to behave like a targeted delivery vehicle, using the body’s existing immune training.
So the team engineered the phage to recognize and bind to proteins called αvβ3 and αvβ5 integrins. Those proteins are abundant on many tumor cells and largely absent from healthy ones. They also modified what the phage delivers. programming it to produce instructions for making a malaria-specific antigen—an immune signal the body recognizes as foreign.
The researchers then put the plan through its paces in 60 mice with cancerous tumors just beneath their skin. Fifteen mice were given a malaria vaccine and two weeks later received six tail injections of the engineered phages over the next two weeks. The rest acted as controls: 15 received no intervention, 15 received the malaria vaccine alone, and 15 received only the engineered phages.
In 44 per cent of the treated mice, the tumors were eradicated and hadn’t returned a year later, when the study ended. The treated mice also lived longer than the control groups, which experienced no survival benefit.
David Withers at the University of Oxford pointed to a practical limitation that has long shadowed many cancer-killing virus strategies. These “modified viruses can be administered systemically into the mouse and they then specifically find out the tumour cells and infect these. ” he said. That. he argued. improves on current approaches to manipulate tumours using oncolytic viruses. which infect and destroy cancer cells but require injections directly into the cancer. In metastatic disease, where cancer spreads, targeting all the sites becomes an impossible task.
The researchers also think the concept could travel beyond malaria.
Hajitou said adjusting the phage’s antigen-making instructions should mean the approach works for people vaccinated against other infections. including seasonal flu or covid-19. “Other vaccines, stronger than malaria, should work even better,” he said. “The principle is to exploit pre-existing immune memory, [it’s] not something unique to malaria.”.
Now the science is moving into the regulatory and clinical stage. The researchers are in talks with the Medicines and Healthcare Products Regulatory Agency (MHRA) in the UK about assessing the approach in an early-stage trial in people, which they hope to begin next year.
phages cancer immunotherapy vaccine immunity malaria vaccine engineered viruses tumor targeting integrins oncolytic viruses MHRA early-stage trial