A new study has shown use of a RNA nanoparticle as vaccine against cancer that uses the immune system response against viral infection. The vaccine induces immune responses in mouse tumor models and in three patients with advanced melanoma.
GERMANY – The study has been published in the journal Nature. Authors are researchers from several German centers such as BionTech AG, a fully integrated development of individualized cancer immunotherapies biotechnology firm, Johannes Gutenberg University and the Hospital of the University of Heidelberg. According to the researchers, the new finding is likely to be a step towards a universal vaccine for cancer immunotherapy.
The team, led by Ugur Sahin, CEO of BionTech AG, researched the characteristics of the immune cells (dendritic cells) in mice using a vaccine administered intravenously. The vaccine is nanoparticles composed of RNA surrounded by lipoplex-RNA; a membrane lipids (fatty acids), similar to a cellular membrane.
Sahin said that the study presents a new class of vaccines extraordinarily potent against cancer that allow effective redirection of the immune system against a wide range of tumor antigens. This is an important step towards cancer immunotherapies truly customized and applicable to all types of cancer.
They found that adjusting the net electric charge of nanoparticles to slightly negative was sufficient to effectively target dendritic cells. In addition, it is a quick and inexpensive method to produce.
The lipoplex protects RNA from being decomposed by the body, and mediates its absorption in macrophages and dendritic cells in spleen, lymph nodes and bone marrow, where the RNA is then translated into a specific cancer antigen.
The authors state that this triggers a strong response to the antigen-specific T cells and causes a potent interferon-α dependent rejection (IFNa dependent) progressive tumors in various mouse tumor models.
In the preliminary results of phase I of the clinical trial, three patients with melanoma treated with low doses of IFN showed a strong response of antigen specific T cells.
To date this RNA-LPX vaccine has been well tolerated without serious adverse effects. Since any peptide-based antigen can be encoded as RNA, this vaccine is potentially applicable to all types of cancer and may represent “a universal platform for cancer immunotherapy,”