Autologous cytomegalovirus-specific T cells as effector cells in immunotherapy of B cell chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (B-CLL) cells express low levels of co-stimulatory molecules and therefore fail to induce activation and differentiation of tumour-specific T cells. We have shown that patients with B-CLL have considerably expanded numbers of cytomegalovirus (CMV) reactive CD8(+) T cells. This study demonstrated that B-CLL cells loaded with CMV peptide not only promoted the ex vivo expansion of autologous, in vivo-generated virus-specific T cells, but also constituted excellent target cells for these cytotoxic Tcells, even without ex vivo re-stimulation. Directing virus-specific T cells to B-CLL may overcome the inadequate immunostimulatory capacity of these cells, which could be exploited for T-cell mediated immunotherapy.