The present invention provides a vaccine for the prophylactic or therapeutic treatment of a tumour in a mammalian subject, as well as methods of using the vaccine, including in treatment of tumours and in generating a CTL response. The vaccine comprises a plurality of nanoparticles and a pharmaceutically acceptable carrier, salt or diluent. The nanoparticles comprise a core comprising a metal and/or a semiconductor atom； and a corona comprising a plurality of ligands covalently linked to the core, wherein at least a first ligand of said plurality comprises a carbohydrate moiety that iscovalently linked to the core via a first linker, and wherein at least a second ligand of said plurality comprises an epitopic peptide that is covalently linked to the core via a second linker, said second linker comprising a peptide portion and a non-peptide portion, wherein said peptide portion comprises the sequence X
