MIT's viral nanofiber could help create personalized cancer vaccines

Researchers at the Massachusetts Institute of Technology (MIT) have engineered a harmless virus into a nanoscale delivery platform that could help create personalized cancer vaccines. By controlling how densely cancer-targeting proteins are displayed on the virus, the team developed vaccine particles that significantly reduced tumor development in mice.

The platform uses a modified bacteriophage called M13, a virus that infects bacteria but is harmless to humans. It forms a long, thread-like structure called a nanofiber that can be coated with antigens, proteins that help the immune system recognize specific targets. The researchers found that adjusting the concentration of these antigens on the viral structure changed how effectively the vaccine stimulated an immune response.

This could allow scientists to customize the particles with different antigens to target individual patients’ tumors. The study was led by researchers at MIT’s Koch Institute for Integrative Cancer Research. Angela Belcher, a professor of biological engineering and materials science and engineering, was the senior author, while research scientist Shengnan Huang led the work.

Tuning the viral vaccine structure The M13 bacteriophage consists of a single strand of DNA surrounded by a protein shell, or capsid. The researchers modified a capsid protein called pVIII, attaching cancer antigens to its surface by incorporating the corresponding genetic instructions into the virus.

However, controlling how many antigen-bearing proteins appeared on the viral structure was important. The researchers found that adding one or two negatively charged amino acids to the pVIII protein increased antigen density. They could further adjust it by introducing a genetic mutation that slowed antigen production.

Using these techniques, the team produced particles displaying the model antigen SIINFEKL at densities ranging from 6 to 70 percent. When tested in mice, a vaccine with 35 percent antigen density provided stronger protection than one with 6 percent. Mice receiving the higher-density vaccine were less likely to develop tumors after exposure to melanoma cells carrying the same antigen.

They also produced more T cells targeting the cancer-associated protein. The researchers found that dendritic cells, which help activate T cells, were more likely to take up particles displaying higher antigen densities. Testing protection against colon tumors The team also tested the platform using ADPGK, a neoantigen found specifically in colon tumors in a mouse model.

Neoantigens are proteins that arise from changes in cancer cells and can help the immune system distinguish tumors from healthy tissue. Mice given the higher-density vaccine were significantly less likely to develop colon tumors, suggesting that the platform could be adapted to target different cancer-specific proteins.

Another feature of the system is that the M13 virus can act as its own vaccine adjuvant, a substance that strengthens the immune response. Its single-stranded DNA activates a pathway called TLR9, which helps stimulate the body’s innate immune system. By modifying the virus’s genetic sequence, the researchers could also control this adjuvant activity.

This potentially removes the need to add a separate immune-stimulating ingredient to the vaccine. A modular approach to cancer treatment The platform’s modular design means researchers could replace one antigen with another to target different types of tumors. This could eventually support vaccines tailored to the specific molecular features of an individual patient’s cancer.

The findings build on the team’s earlier work, which explored using M13-based nanovaccines to treat established tumors in mice. In the latest study, however, the researchers primarily tested the vaccine’s ability to prevent tumor development. The approach remains at the preclinical research stage.

Further studies will be needed to determine whether it can safely and effectively treat established cancers and whether the results translate to humans. The research was published in the journal Advanced Healthcare Materials . Get the latest in engineering, tech, space & science - delivered daily to your inbox.

With over a decade-long career in journalism, Neetika Walter has worked with The Economic Times, ANI, and Hindustan Times, covering politics, business, technology, and the clean energy sector. Passionate about contemporary culture, books, poetry, and storytelling, she brings depth and insight to her writing.

When she isn’t chasing stories, she’s likely lost in a book or enjoying the company of her dogs.