Alle gegen einen
(19.03.2020) Das Coronavirus hält Biotech-Firmen weltweit auf Trab. Die einen entwickeln Apps, die anderen Impfstoffe.
RNA vaccines: an introduction
The methods to make mRNA vaccines can be very effective. However, there are technical challenges to overcome to ensure these vaccines work appropriately:
Unintended effects: the mRNA strand in the vaccine may elicit an unintended immune reaction. To minimise this the mRNA vaccine sequences are designed to mimic those produced by mammalian cells.
Delivery: delivering the vaccine effectively to cells is challenging since free RNA in the body is quickly broken down. To help achieve delivery, the RNA strand is incorporated into a larger molecule to help stabilise it and/or packaged into particles or liposomes.
Storage: many RNA vaccines, like conventional vaccines, need to be frozen or refrigerated. Work is ongoing to reliably produce vaccines that can be stored outside the cold chain, since these will be much more suitable for use in countries with limited or no refrigeration facilities.
Safety: better understanding of vaccine adverse effects is needed – these can include inflammation or autoimmune reactions.
Five things you need to know about: mRNA vaccines
4. There are a lot of unknowns
Because mRNA vaccines are only now beginning to be tested in humans, there are a lot of fairly basic unknowns which can only be answered through human trials. ‘What is really the current challenge, I think, is to understand whether these vaccines will really be able to mount a sufficiently protective immune response in the human and to understand, for example, which quantities of mRNA will be needed to do this,’ said Prof. Bekeredjian-Ding.
Other outstanding questions include whether the proteins that have been chosen for the vaccine are the right ones to prevent a coronavirus infection in the body, how targeted the immune response is to this particular coronavirus, how long any immunity would last, and whether it causes side-effects such as increased inflammatory responses like redness and swelling or, in the worst case, aggravates disease.