DEVELOPMENT OF LONG-TERM RAINBOW-TROUT SPLEEN CULTURES THAT ARE HEMATOPOIETIC AND PRODUCE DENDRITIC CELLS

Different tissue dissociation protocols and serum supplements resulted in a variety of primary cultures from rainbow trout spleens. These we re classified as either haemopoietic or non-haemopoietic, In haemopoie tic cultures, a complex stromal layer developed on the cell culture su rface; round cells appeared on the stromal layer; and ultimately some round cells were released into the medium as a non-adherent population . Many non-adherent cells were able to reattach in new culture vessels . Most of these had the characteristic shape and unique motility of de ndritic cells. Cultures of these cells were subcultivated 2-4 times bu t continuous cell lines did not arise. Haemopoietic cultures resulted with collagenase dissociation and maintenance in high foetal bovine se rum (FBS) concentrations. Non-haemopoietic cultures contained adherent cells, including macrophages and fibroblasts, but did not develop a n on-adherent population. These cultures resulted with 10% FBS or horse serum and after explant outgrowth or dissociation with trypsin. Both c ulture types should be useful for studying the regulation of haemopoie sis and the functions of specific immune cells in fish. (C) 1996 Acade mic Press Limited