Animal studies have shown that this "sublingual" surface can take up antigens and stimulate immune responses, which may have a different character to responses induced by injecting the same antigens. In previous studies of nasal and oral delivery, we used licensed vaccine preparations as pure and well−characterised model antigens safe for use in humans. We will use a licensed "HPV" vaccine as the source of antigens in this study. The quantity and character of responses (lymphocyte number and pattern of surface proteins, concentration and type of antibodies in fluids) will be measured in detail in various anatomical sites (blood, vaginal secretions) before and after delivery of antigens on three occasions. As well as using established immune assays to characterise the responses, we will develop new research assays to detect populations of lymphocytes and antibodies present in secretions. To ensure we have positive samples to include in our assays and validate new techniques, we will recruit some subjects to receive a standard intramuscular injection, as this is known to be nearly 100% reliable in inducing measurable immune responses. As this is a preliminary study we will recruit enough subjects (based on our previous experience with nasal, oral and injected delivery) to ensure we generate sufficient responses we can measure. We may be able to draw some tentative conclusions about differences in character of immune responses following sublingual or injected delivery, but it is not the intention of this initial study to formally compare these two routes. If we observe that sublingual delivery in humans can induce immune responses, we can select assays to test any differences more formally in subsequent bigger and more focused studies.