title: Phorbol ester/calcium ionophore activate fish leukocytes and induce long-term cultures.
abstract: This study documents that phorbol ester (TPA) and calcium ionophore (A23187) in combination are potent mitogens for channel catfish peripheral blood leukocytes (PBL), stimulating both catfish T and B cells. Unlike T-cell responses to Concanavalin A (ConA), these responses to TPA/A23187 did not appear to require monocytes and were not strongly inhibited by low culture temperature. These results support the notion that catfish lymphocytes utilize the bifurcating phosphatidylinositol bisphosphate second-messenger system for transmembrane signaling during the activation process, as do mammalian lymphocytes. Furthermore, it was unexpectedly found that TPA/A23187 stimulation of normal catfish PBL reproducibly (greater than or equal to 95%) resulted in the generation of long-term leukocyte cultures that did not require restimulation or the addition of exogenous factors for continued proliferation. These TPA/A23187-induced leukocyte cultures were refractory to cloning and appeared to contain 10-40% monocytes and 50-80% putative T cells with no detectable B cells or neutrophils.
authors.affiliation: Department of Microbiology, University of Mississippi Medical Center, Jackson 39216-4505.
authors.forename: G L
authors.initials: GL
authors.lastname: Lin
authors.forename: C F
authors.initials: CF
authors.lastname: Ellsaesser
authors.forename: L W
authors.initials: LW
authors.lastname: Clem
authors.forename: N W
authors.initials: NW
authors.lastname: Miller
mesh_terms: D000818:Animals; D000001:Calcimycin / Q000494:pharmacology*; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D004357:Drug Synergism; D007059:Ictaluridae / Q000097:blood / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000276:immunology; D008070:Lipopolysaccharides; D008213:Lymphocyte Activation / Q000187:drug effects; D015290:Second Messenger Systems; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D013696:Temperature; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D008070:Lipopolysaccharides; D003208:Concanavalin A; D000001:Calcimycin; D013755:Tetradecanoylphorbol Acetate