Random and directed migration of trout (Salmo gairdneri) leukocytes: activation by antibody, complement, and normal serum components.

Purified peripheral blood leukocytes from rainbow trout (Salmo gairdneri) were used in experiments to determine whether these cells are capable of random or directed leukotaxis in response to immunologically important mediators. Leukocyte migration was assessed by the use of microporous filter penetration assays and migration-under-agarose tests. Leukocyte migration rates were enhanced in filter penetration assays by the presence of antigen-antibody-complement complexes, and chemotactic migration was observed in migration-under-agarose tests as a response to whole trout serum. Trout leukocytes thus altered normal migratory activities in response to chemical changes in their immediate environment. The role of complement in chemotaxis may be similar in fish and mammals.