The Nobel Prize in Physiology or Medicine was awarded to Katalin Karikó and Drew Weissman on Monday, for their discoveries that led to the development of effective vaccines against Covid-19.
Together, Dr. Karikó and Dr. Weissman, who met over a copy machine at the University of Pennsylvania in 1998, transformed vaccine technology. Seven years later, they published a surprising finding about messenger RNA, also known as mRNA, which provides instructions to cells to make proteins.
When mRNA was introduced to cells, the molecules were so delicate that the cells instantly destroyed it. But the scientists found that they could avert that outcome by slightly modifying the mRNA. When they added the altered mRNA to cells, it could briefly prompt cells to make any protein they chose.
Up to that point, commercial vaccines had carried modified viruses or pieces of them into the body to train the immune system to attack invading microbes. An mRNA vaccine would instead carry instructions — encoded in mRNA — that would allow the body’s cells to pump out their own viral proteins.
This approach, Dr. Weissman and Dr. Karikó thought, would better mimic a real infection and prompt a more robust immune response than traditional vaccines did.
The prize is the first of six Nobel Prizes that will be awarded this year. Each award recognizes groundbreaking contributions by an individual or organization in a specific field: physiology or medicine, physics, chemistry, economic science, literature and peace work.