Nanoparticle RNA Vaccines Are Remarkably Effective in Mice

Traditional vaccines take a long time to produce in large amounts, whether they are live-attenuated vaccines or killed microbe vaccines. This is a particular problem when new epidemics emerge suddenly.

A team at the Massachusetts Institute of Technology and Harvard created nanoparticles that contained a “payload” of RNA that encoded particular proteins. The RNA was in the form of a replicon: a start signal, the code for the protein, then a stop signal. Once inside a cell, a replicon can keep churning out protein. Injecting mice with the nanoparticle vaccine led to robust, specific antibody and CD8⁺ cell responses. Finally, single doses of vaccines for H1N1 influenza, Toxoplasma gondii, and Ebolavirus provided durable protection to mice again…