A method for generating a T cell immune response in a host involving administering a vectored vaccine comprising a non-replicating or replication impaired viral vector expressing the translation product of a mycobacterial antigen 85A gene. Vectored vaccines and uses thereof are also provided. Also provided is a method of inducing a CD8 and a CD4 memory T cell response against an antigen using an adenovirus vector expressing an antigen or an immunogenic fragment thereof.