Cytotoxic T cells belong to a sub-group of T lymphocytes that are capable of inducing the death of infected somatic cells or tumour cells. Most cytotoxic T cells express T-cell receptors that can recognise a specific antigenic peptide bound to Class I MHC molecules and the CD8 glycoprotein. Our CD8+ Cytotoxic T cells are isolated from peripheral blood of healthy donors using immunomagnetic positive selection for CD8+ cells. Immediately after isolation, the CD8+ Cytotoxic T cells are cryopreserved. They are characterized using flow cytometry and have a purity of >95%.