A potential vaccine that targets the bacterial toxins may soon be on the anvil, say researchers.

Instead of invading pathogens, the new vaccine would be the first to target bacteria already in human skin. The researchers demonstrated that antibodies to a toxin secreted from bacteria in acne vulgaris can reduce inflammation in human acne lesions.

"Once validated by a large-scale clinical trial, the potential impact of our findings is huge for the hundreds of millions of individuals suffering from acne vulgaris," explained lead investigator Chun-Ming Huang, from the University of California-San Diego, US. 

An acne vaccination could circumvent potential adverse effects of topical or systemic retinoids and antibiotics, the current treatment options. They found that Christie-Atkins-Munch-Peterson (CAMP) factor -- a toxin secreted from the Propionibacterium acnes (P. acnes) bacteria, can induce inflammatory responses.

In the study, published in the Journal of Investigative Dermatology, the team explored in mice and ex vivo in human skin cells whether they could inhibit inflammation by employing antibodies to neutralise this virulence factor. Their findings show that the application of monoclonal antibodies to CAMP 2 factor did indeed decrease the inflammatory response.

"While addressing an unmet medical need and providing an appealing approach, acne immunotherapies that target P. acnes-derived factors have to be cautiously designed to avoid unwanted disturbance of the microbiome that guarantees skin homeostasis," said Emmanuel Contassot, from the University of Zurich in Switzerland. Future studies will address these factors and focus on engineering a non-toxic chemical or targeted vaccine formulation for its human application, the researchers said.