This article explores the advantages and limitations of RNA/DNA Vaccines.
RNA and DNA are types of genetic material that encode specific proteins.
Specific SARS-CoV-2 proteins, for example the spike proteins which mediate viral entry into cells, can be used as vaccine antigens. On vaccination with RNA or DNA, this genetic material enters human cells and uses the cell’s machinery to produce the protein they encode. The immune system then recognises this protein and produces an immune response which may be able to protect against subsequent natural infection. The image below explains this process.
If you need a text version of the above image, this is available as a PDF.
In the video below Professor Robin Shattock gives an overview of the COVID-19 RNA vaccine developed at Imperial College London.
This is an additional video, hosted on YouTube.
A PDF summary of the video can be found in the downloads section below.
RNA and DNA vaccines are a relatively new type of vaccine and no vaccines of this are currently licensed.
Advantages
Limitations
Do not involve any infectious agents so are suitable for most people
The immune response generated may not be as potent as that induced with vaccines that contain complete SARS-CoV-2 virus
Can be manufactured more quickly and for less cost than egg-based vaccines
Multiple doses may be required
Potential to be given by different routes so could be needle-free
Low cost
Antigen sparing (only small amounts of material needed so there is potential to make more vaccines
RNA/DNA vaccines have many advantages, and due to their novelty we are still learning more about them all the time. The next step will look at viral vectored vaccines, which utilise genetic material from the infectious agent.