We developed a novel model system for hypersensitive cell death, in which the elicitor induced cell death in suspension-cultured cells with 100% efficiency. The 100% efficient cell death was achieved when tobacco BY-2 cells at stationary-phase were diluted to 1×105 cells/ml with conditioned medium and treated with 1.5 μM of cryptogein, an oomycete-derived proteinaceous elicitor. During the cell-death process, nuclear chromatin fragmentation, activation of several genes associated with hypersensitive response (HR), and induction of several genes related to antimicrobial activity were observed. The results strongly suggest that the cells undergoing HR cell death activated antimicrobial mechanism while executing cell-death program.