A new vaccination method induces a potent anti-viral response

25 September 2014

BPRC - 1. A new vaccination method induces a potent anti-viral response

In the search for a vaccine against HIV, many obstacles have to be overcome. For example, a vaccine should not only provide protection against disease, but must also be safe and large-scale production should be as cheap as possible. Researchers at the BPRC have tested a new vaccine that may meet these criteria.

For several disease, the use of attenuated pathogens as vaccine provides protection in experimental settings. Unfortunately, it is not always feasible to apply this way of vaccination for general use, because of the risk that the attenuated pathogen mutates and causes disease, and/or because large-scale production is too costly.

Another way of vaccination is the use of a purified form of a protein component of the disease agent in conjunction with an adjuvant. This method is often safe and relatively inexpensive. Unfortunately, this method often does not protect against disease.

Years ago, a new method appeared to provide a potential solution: vaccination with genetic material (DNA). DNA vaccination induced strong immune responses in rodent models. Unfortunately, this was not the case in monkeys and humans.

Recently, a new variant of DNA vaccination has been developed: self-replicating RNA, a strong DNA-like carrier of the genetic material. Its production is relatively cheap and problems with safety have not been observed.

Researchers at the BPRC have now tested the safety and immunogenicity of a new anti-HIV RNA vaccine, combined with an adjuvant, in rhesus monkeys and compared it with two ‘traditional’ methods of vaccination that previously showed good immune responses in humans. The results of this study, published in The Journal of Infectious Diseases, show that this synthetic RNA vaccine is safe and induces a strong immune reaction, even stronger than the reactions that were generated using traditional vaccination methods. More research is needed to test whether this immune reaction also offers effective protection against disease.