IFNG and plasma cell myeloma: Indeed, while MaMs-based ELISpot test promptly describes the active IFN-γ secretory profile of circulating myeloma-specific T cells, the ex-vivo expansion experiments disclosed the clonogenic potentials and killing activities of such T cells, eventually suggesting that some circulating, highly active IFN-γ secreting effector T cells could be almost terminally differentiated and, thus, less expandible in vitro.