The graft-versus-host reaction (GVHR) in the ginbuna crucian carp, Carassius auratus langsdorfii

A model system of clonal triploid ginbuna and tetraploid ginbuna-goldfish hybrids was employed to demonstrate the presence of graft-versus-host reaction (GVHR) in a teleost Gsh. Tetraploid scale grafts on triploid clone members evoked an acute rejection, whereas the reverse transplants were accepted. When sensitized triploid cells were injected into tetraploid recipients, a typical GVHR was induced, leading to death of the recipients within one month. The onset of illness appeared about one week after cell injection as a loss of appetite and constipation, followed by a scale protrusion: severe haemorrhage, local destruction of the ventral skin and prominent splenomegaly. GVHR was most effectively induced by head-kidney cells and peripheral blood leukocytes (PBL), followed by spleen and thymus cells. Donors had to be sensitized at least twice by scale grafting to induce the reaction. A considerable number of recipients injected with cells from donors which had been sensitized by allogenetically different tetraploids died, suggesting a limited poly morphism or heavy cross-reactions between the alleles of the histocompatibility antigens. Ploidy analyses revealed that donor cells greatly increased in the host liver and spleen, constituting approximately 30% of total cells after 2-3 weeks. Most of these features of acute GVHR observed in this fish system are quits similar to those found in mammals and birds, thereby suggesting the presence of allo-reactive cytotoxic T lymphocytes in teleosts. (C) 1999 Elsevier Science Ltd. All rights reserved.