A Study of the Immunogenicity of M. Bovis BCG (SSI Strain), Delivered Intradermally in Healthy Volunteers

Volunteers for the study will be recruited through advertisements. Each volunteer will have received an information sheet concerning the study and will have agreed to participate in writing.

Volunteers will be given at least 48 hours between reading the information leaflet and agreeing to participate. Female volunteers will have a pregnancy test prior to enrollment. Volunteers will give signed consent for their GP's to be notified about their participation in the trial. The GP will be faxed a letter on the day of screening and asked to reply if they know of a reason why the volunteer should not take part. The signed consent form will also be faxed with the letter.

A week after the screening visit and after a negative Heaf test, subjects will receive a single intradermal injection of 106 cfu M. bovis BCG in 0.1ml just inferior to the insertion of the deltoid muscle. Blood tests will be taken at the screening visit and day of immunisation, 1 and 2 weeks, and 1, 2, 3 and 6 months after the immunisation. 75mls will be taken on the screening visit, and 60mls will be taken on all subsequent visits. Screening samples will be tested for full blood count, biochemical screen and immunological assays to determine vaccine immunogenicity. Peripheral blood mononuclear cells will be prepared for cellular immunological assays to be performed without or following cryopreservation. Other serological measures of immune response, i.e.

antibody titres, will be assayed on frozen plasma samples. All blood tests will be taken within 1-3 days of the due date as described in the schedule above.