Study clarifies basic mechanism of novel needle-free vaccination

IVI’s scientists have discovered  a mechanism by which a vaccine applied on the skin can cause an immune response in the gut, as well as in the body.

Transcutaneous immunization (TCI), a recently developed needle-free vaccination method, involves applying a vaccine onto the skin using a patch. In previous animal and human studies, TCI was found to induce robust immune responses in blood and in mucosal secretions.

IVI post-doctoral fellow Chang Sun-young found in an animal study that dendritic cells – cells that “capture” vaccines and carry them to the immune system – were induced by TCI in the lymph nodes draining the gut and were involved in the initiation of intestinal antibody responses, which are essential to stopping bacteria and virus infections. “These findings explain how intestinal immune responses are induced after immunization via skin, the reason for which had remained elusive until now,” said Dr Chang.

“These findings suggest that an efficient ‘cross-talk’ exists between the skin and gut immune systems and appears to be mediated by specialized dendritic cells in lymph nodes draining the intestines,” said Dr. Kweon Mi-na, Chief of the Mucosal Immunology section of the Laboratory Sciences Division who led the study. The study was published in an April 2008 issue of the Journal of Immunology. (Read the journal article)

“These findings challenge the traditional notion that ingesting vaccines is the only means for inducing immunity in the gut. The results reported by Dr. Kweon’s team not only supports the notion that administering a vaccine in a skin patch can do the job but also provides a clue as to why this approach works,” explained Dr. Cecil Czerkinsky,  IVI’s Deputy Director-General for Laboratory Sciences.