Worldwide, a corona vaccine is being worked with great effort. They work with RNA, mRNA and now also: counterfeit spikes of the corona particle. Will this be the breakthrough we so badly need?
Scientists from the Laboratory of Virology of Wageningen University Research sincerely hope so. The research is a European initiative of the pharmaceutical industry and the universities in Copenhagen and Tübingen, which called in the help of Wageningen, but also from the Leiden University Medical Center. There they have the know-how to work with the infectious coronavirus. The result is an approach that turns out to be different from others: the scientists are working on the fabrication of the now well-known spikes, which adorn the corona particle.
Insect cell spikes
The aim is for our immune system to sound the alarm and start producing antibodies against the corona virus, without this virus having to be processed in a vaccine itself. The immune system only needs to recognize the spikes of the infectious culprit, without actually having to deal with it. If the immune system makes antibodies against the fake spikes, these antibodies will work, if they detect the real spikes of the harmful virus and there is therefore immunity.
The spikes proteins are made from insect cells, a method that is also used at WUR in making vaccines against, for example, the Zika virus. According to virologist Dr. Gorben Pijlman of Wageningen University, there are clear advantages to this. “Insect cells can quickly and safely produce large amounts of proteins. In Wageningen we use cells from the moth Spodoptera frugiperda . It introduces the DNA code of the spikes, which are on the outside of the coronavirus. ”
Suitable for mass production
The method will lend itself well to large-scale manufacturing, which is of course important when it comes to a vaccine, which must be able to be produced in large quantities. “In our lab we have bioreactors from one to fifteen liters. They are large enough to quickly produce test proteins for animal testing. If it turns out that the method of our consortium is successful and you actually want to market it as a vaccine, you will scale up to larger bioreactors. In industry, for example, in these types of cultivation processes, they work with reactors up to two thousand liters in size, ”says Pijlman.
It may take another year and a half before a vaccine based on this can be used. Other vaccines may be available before. That is not a concern for Pijlman. “We don’t see this as a competition. There is great solidarity and openness among researchers. It is only good that there are several methods with which a vaccine is now being developed. In addition, all strategies may eventually yield a combined approach. For example, a combination of two vaccines that have different mechanisms of action, and thus reinforce each other. ”
Research also suitable as a test
Incidentally, it is not the case that the work with the fake spikes should lead to the development of only a vaccine. The research is also suitable for other applications, such as developing tests. It can be used to determine whether people are already immune. If someone has already made antibodies from the virus, these antibodies will also respond to the fake spikes. Based on those facts, corona tests can very well be developed with this research.
The question now is when the vaccine should be ready and can be used. Pijlman believes that the project is well on schedule. “Within our consortium, the first successful animal experiments have already been carried out with a candidate vaccine, which is based on the RBD or receptor-binding domainof the spikes. This is the most important part of the spikes and may in itself already be sufficiently recognized by the immune system. The spikes that are developed in Wageningen and with other partners are larger and more complete and therefore even more recognizable than the RBD, but are also more difficult to produce. We expect that our spikes will also be tested after the summer. Then it remains to be seen whether the RBD vaccine gives good results in clinical tests. If not, if the animal experiments are successful, we can fall back on the more complete spikes of us or of fellow researchers. ”
Where we could not air or see the spikes of the virus particle for a long time, we now eagerly look forward to the success of the artificial versions. And the vaccines and tests that can be made with them.