UPDATED: Getting under the skin of vaccines

No one likes getting shots, especially those ones deep into the muscle. Research published in Nature may make jabs a bit less painful in the future, as well as a bit more effective. In fact, the data show the body's immune system may respond better to vaccines given into the top layers of the skin, rather than under the skin or in the muscle.

The best immune response was thought to be from the immune cells in the blood stream and lymph nodes (circulating central memory T cells or TCM cells). However, this received wisdom could change, as this study showed that mice with a viral skin infection had a stronger immune response from long-lasting immune cells called T resident effector memory (TREM) cells than from the TCM cells. The mice were protected more effectively from future infections with the same virus. The TREM cells were seen throughout the mice's entire skin, not just at the point of infection. They are also found in other places where viruses might enter the body--such as the lungs, GI tract, and other epithelial tissues--so this response could be relevant to a wide range of infections.

"Putting this research in historical context, it helps explain the uniquely powerful efficacy of the first successful vaccine developed for smallpox by Jenner in 1796," said Dr. Thomas Kupper, the Thomas B. Fitzpatrick Professor of Dermatology at Harvard Medical School and senior author of the Nature paper. "Syringes had not yet been invented, so Jenner administered the first vaccine by disrupting the upper layers of skin with a specialized needle, a process similar to how the vaccinia virus was delivered in our study. It is worth remembering that the smallpox vaccine remains the most effective vaccine in the history of medicine, resulting in the elimination of smallpox in human populations."

The research was carried out at Harvard, and TREMRx, a biotechnology company founded by Kupper and developing vaccines delivered to the skin, has exclusive rights to the IP. If clinical trials support these early results, TREMRx's approach could change how vaccines are delivered. After all, if this approach worked for Jenner in 1796, it could work for us!

- read the press release
- see the abstract in Nature

Editor's Note: The story has been updated to clarify Hardvard's relationship with TREMRx