Cancer vaccine from harmless viruses: MIT packs tumour antigens more densely on nanofibres
An MIT team uses the M13 bacteriophage, harmless to humans, as a carrier for cancer antigens. A more densely loaded version (35 instead of 6 percent) protected mice better from tumours.
Archive image · Photo: Either Ada / Wikimedia Commons, CC BY-SA 4.0 (cropped and resized)
Researchers at the Koch Institute of the Massachusetts Institute of Technology (MIT) have refined a toolkit for personalised cancer vaccines. It is based on the M13 bacteriophage, a virus that is harmless to humans and forms a nanofibre that can be loaded with cancer antigens. The study, led by Professor Angela Belcher with first author Shengnan Huang, appeared in the journal "Advanced Healthcare Materials"; MIT presented it on 30 October.
The team attached antigens to a coat protein of the virus and was able to tune their density through small changes to the protein sequence – from 6 to 70 percent. In mice, a version with 35 percent antigen density protected best: after exposure to melanoma cells, the animals developed tumours much less often and produced more matching T cells. With a neoantigen from a mouse model of colon cancer, too, the more densely loaded vaccine markedly reduced the risk of tumours. No separate adjuvant was needed because the phage's own genetic material activates the innate immune system.
"The great thing about this is that it's modular and we could switch out different antigens on demand," says Belcher. So far only prevention has been tested, in mice; there are no human data. The work was funded in part by the US Defense Advanced Research Projects Agency (DARPA).