Microneedles trigger better responses to flu vaccine

Recent research suggests that injecting vaccines just under the skin gets a better immune response, but how to get the vaccine to just the right spot? Research from Georgia shows that microneedle patches could be just the approach by looking at the way the immune system responds.

Microneedle patches, tiny toothed patches loaded with vaccine, are designed to get the right dose to just the right place in the skin and are virtually painless, which is an added bonus. The researchers from Emory School of Medicine and Georgia Institute of Technology used the microneedle patch to deliver a flu shot to mice, and saw a rise in cytokine (cell signaling molecules) levels in the area where the shot was delivered. The role of cytokines is to recruit immune cells, which then respond to the antigens (viral targets) in the vaccine. Another feature of this form of vaccination was that the antigens remain in the skin longer, which may help their take-up by the immune cells, which then move away from the skin. This may help improve the immune response.

"Our research reveals new details of the complex but efficient immune response to influenza virus provided by microneedle skin patches," says Richard W. Compans, Ph.D., Emory professor of microbiology and immunology. "Despite the success of vaccination against influenza, the virus has many subtypes, mutates rapidly and continues to elude complete and long-term protection, and therefore requires annual vaccination with an updated vaccine each year."

Microneedle shots are much less painful, and carry less of a contamination and safety risk than ordinary hypodermic shots. Combined with the improved immune response, these could make the microneedle a new route to disease prevention, especially for the needle-phobic. Unless, of course, the phobia extends to microneedles.

- read the press release
- see the abstract in mBio