A study in PNAS in August 2022 presented an mRNA vaccine for cancer that targets the lymph nodes instead of the liver. Researchers at Tufts School of Engineering believe that this method is “so strong and precise, it eliminates tumours and even prevents their recurrence”.
This vaccine delivers mRNA in small lipid bubbles that fuse with cells that can then produce viral antigens. Specifically, the lipid nanoparticles (LNPs) “zero in on the lymphatic system”. The team created LNPs that “favoured delivery to the lymph nodes over the liver by a three-to-one ratio”. Professor Qiaobing Xu stated that “targeting the lymphatic system helped us to overcome many of the challenges that have faced others in developing a cancer vaccine”. He and his colleagues have previously targeted LNPs to the brain and liver, as well as the lungs.
Tufts reported that over 20 mRNA cancer vaccine candidates have progressed to clinical trials, but “usually much of the mRNA ends up in the liver”. On the other hand, in the lymph nodes, the vaccine was “absorbed by about a third of dendritic cells and microphages”. This produces more B and T cells, which in turn cause a stronger immune response.
Mice with metastatic melanoma demonstrated “significant inhibition of tumours and a 40% rate of complete response” when treatment was “combined with another existing therapy”. Furthermore, the cancer vaccine prevented additional tumour formation, suggesting “excellent immune memory”.
Postdoctoral researcher fellow, Dr Jinjin Chen, stated that “cancer vaccines have always been a challenge”. This is because the tumour antigens don’t appear as “foreign” to the body and the tumours can inhibit the immune response.
“This cancer vaccine evokes a much stronger response and is capable of carrying mRNA for both large and small antigens”
The hope is that this vaccine will become a “universal platform” for effective vaccines against more viruses and other pathogens as well as cancers.
To get updates on cancer vaccine technology at the World Vaccine Congress in October 2022 click here for your tickets.
