Delivering vaccines using prebiotic spores
24 Oct 2012
Scientists at Royal Holloway have developed a pioneering new method of oral vaccination.
Lead scientist Professor Simon Cutting, from the School of Biological Sciences at Royal Holloway, has developed the method through the use of probiotic spores.
He carried out fundamental studies into the biology of the bacterium Bacillus subtilis which attracted the attention of microbiologists due to its ability to form spores that can last millions of years before germinating under the appropriate environmental conditions.
Cutting said: “The mechanisms by which this process occurs have fascinated microbiologists for decades making it one of the most intensively studied bacteria. Its simple life cycle and ease of use make it an ideal laboratory subject.”
Cutting discovered that the Bacillus spores act as ideal vehicles to carry antigens and promote an immune response.
He explained: “Rather than requiring needle delivery, vaccines based on Bacillus spores can be delivered via a nasal spray, or as on oral liquid or capsule.
“Alternatively they can be administered via a small soluble film placed under the tongue, in a similar way to modern breath freshners. As spores are exceptionally stable, vaccines based on Bacillus do not require cold-chain storage alleviating a further issue with current vaccine approaches.”
As well as eliminating the pain associated with needles, oral vaccines provide greater benefits including being safer to administer, especially in developing countries where HIV is rife, being inexpensive to produce and easier to store and reducing concerns of adverse reactions.
Cutting has carried out pre-clinical evaluation of Bacillus-based vaccines for a number of diseases including Tuberculosis, influenza and tetanus but most recently he has been investigating the potential for use of the vaccines against a disease of particular relevance to the West - Clostridium difficile.
“Currently, there is no vaccine against the disease, and although several approaches are currently undergoing clinical trials, none are expected to provide full protection, and new solutions are urgently needed,” said Cutting.
He added: “Bacillus based vaccines offer distinct advantages as unlike other approaches, oral delivery can cause a more specific immune response in the gastrointenstinal tract to fully eliminate C.difficile.”
Cutting has recently received private seed investment to form a company, Holloway Immunology, to develop the bacillus vaccine technology.