Microneedle vaccine patches may be more effective than traditional inoculation, report shows

According to research conducted by a team of Emory University and Georgia Tech University scientists, microneedle vaccine patches were more effective at delivering influenza protection in mice than intramuscular or subcutaneous inoculation.

The skin contains a rich network of antigen-presenting cells, which can signal the immune system if attacked. The researchers observed that microneedle skin immunization with the inactivated influenza virus resulted in an increased immune system reaction, Science Daily reports.

Microneedle vaccination may also lead to a prolonged depositing of antigen, which could allow for a more efficient uptake by cells that present antigens.

"Our research reveals new details of the complex but efficient immune response to influenza virus provided by microneedle skin patches," Richard W. Compans, an Emory professor of immunology and microbiology, said, according to Science Daily. "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."

Skin immunization led to a local increase in cytokines. Cytokines are important for the recruitment of dendritic cells, monocytes and neutrophils, which are all important in the activation of a strong innate immune response against the influenza virus.

"New vaccine formulations and delivery methods such as vaccine-coated microneedle patches could provide an improved protective response, which would be of particular benefit to those at high risk of related complications," Compans said, according to Science Daily. "Vaccine delivery to the skin by microneedles is painless, and offers other advantages such as eliminating potential risks due to use of hypodermic needles."

The research was supported by grants from the National Institute of Biomedical Imaging and Bioengineering and the National Institute of Allergy and Infectious Diseases.