Evaluation of the sublingual route of immunisation for the induction of mucosal and systemic immune responses to polysaccharide-protein conjugate vaccines

Dr Sudaxshina Murdan, Associate Professor
School of Pharmacy, University College London (UK)
Sudaxshina Murdan
Dr Fatme Mawas, National Institute for Biological Standards and Control, MHRA (UK)
Dr Seanette Wilson, The Biovac Institute (Biovac) (South Africa)

The aim of this project is to investigate whether administering a vaccine under the tongue (i.e. sublingually) is more effective than injecting the vaccine, with the goal of preventing infections such as those caused by group A and group B streptococci bacteria. Infections caused by these bacteria result in significant illness and mortality burden, especially in low and middle income countries, and there are no vaccines against these streptococci. A new type of vaccine against group B streptococcus is currently being developed by the industrial partner, and this vaccine will be used to test the aim.   

The sublingual route has been selected for its advantages over the injection. Injected vaccines do not always elicit immune responses at the body’s surfaces where group A and group B streptococci enter, infect or are transmitted to others, such as the nose, mouth, intestine, lungs and vagina. In contrast, when vaccines are administered sublingually, immune responses are generated at these sites and in the blood. Immunity at all these places (elicited by sublingual vaccine administration) is therefore more likely to prevent infection by group A and group B streptococci. In addition, the sublingual route avoids the needle and associated problems. In this project, we will administer the vaccine sublingually to experimental animals. Control animals will receive the vaccine by injection. Immune responses in the blood, mouth, nose, intestine and vagina will be measured. The results will establish the potential superiority of the sublingual route for administration of the type of vaccine used.