Moderna’s COVID-19 vaccine stimulates an immune response in people
An experimental vaccine may help protect against a coronavirus infection, preliminary results from people and mice suggest. One or two doses of an mRNA vaccine prod people’s bodies to make as many or more antibodies against the coronavirus as are made by people who have recovered from COVID-19, researchers from Moderna, Inc., announced May 18. Moderna, based in Cambridge, Mass., and the U.S. National Institute of Allergy and Infectious Diseases in Bethesda, Md., worked together to develop the vaccine, known as mRNA-1273 (SN: 2/21/20). Their approach uses messenger RNA, or mRNA, a genetic molecule that cellular machinery reads in order to build proteins. In this case, the mRNA contains instructions for building the coronavirus’ spike protein, which helps the virus enter human cells. The vaccine induces human cells to make the spike protein. The immune system then makes antibodies to latch onto the spike proteins. Should a vaccinated person encounter the virus later, those vaccine-stimulated antibodies may prevent the virus from infecting healthy cells. Mice vaccinated with these...