Cell-mediated cytotoxicity in isogeneic ginbuna crucian carp

This review describes recent studies on cell-mediated cytotoxicity of fish using clonal triploid ginbuna and discusses the excellent potential of this species as a model for studying fish immunology. Graft-versus-host reaction (GVHR) followed by in vitro cell-mediated cytotoxicity against allogeneic erythrocytes and cell lines are described as specific cytotoxic activity in ginbuna. In vivo and in vitro cell-mediated cytotoxicity obtained with ginbuna are characterised in terms of the requirement for repeated sensitisation of effector cell donors to induce cytotoxicity, killing of allogeneic recipients or cells but not isogeneic targets by effector cells, and the lack of involvement of ADCC. These results suggest that cytotoxicity in ginbuna is mediated by allo-reactive cytotoxic T cells rather than non-specific cytotoxic cells. Spontaneous cytotoxic activity of ginbuna neutrophils is also described with NK activity against human leukemic cells and spontaneous killing of isogeneic erythrocytes.