title: In vitro effects of staphylococcal leukocidin LukE/LukD on the proliferative ability of lymphocytes isolated from common carp (Cyprinus carpio L.).
abstract: Various strains of Staphylococcus aureus bacteria produce bicomponent toxins such as leukocidin LukE/LukD consisting of two subunits S (LukE) and F (LukD). The toxin subunits bind to leukocyte cell membrane inducing transmembrane pore formation and subsequent cell lysis. There is a lack of data on the effects of staphylococcal leukocidin LukE/LukD on fish immunocompetent cells in vitro. The purpose of the study was to determine the influence of leukocidin LukE/LukD on the proliferative ability of T and B lymphocytes isolated from head kidney and spleen of common carp (Cyprinus carpio L.). The response of T and B lymphocytes was stimulated with concanavalin A (ConA) and lypopolysaccharide (LPS) respectively and measured by the MTT test. The results revealed the modulatory influence of staphylococcal leukocidin LukE/LukD on the proliferative ability of fish T and B lymphocytes. The highest concentrations (5000-25000 ng ml(-1) of medium) of complete leukocidin LukE/LukD and its subunit LukE induced statistically significant suppression of both head kidney and splenic T and B lymphocyte proliferation. On the other hand, the lowest concentrations of the complete toxin (0.32-1.6 ng ml(-1) of medium) caused slight but statistically significant stimulation of both head kidney and splenic T and B lymphocyte proliferative ability. No modulatory effects were observed at any concentration of subunit LukD used in the experiment. There is a need for further studies concerning the susceptibility of other immune cell populations isolated from fish to different types of staphylococcal leukocidin.
authors.affiliation: Department of Physiology and Toxicology, Catholic University of Lublin, 4 Norwida Str., 20-061 Lublin, Poland. adambownik@wp.pl
authors.forename: Adam
authors.initials: A
authors.lastname: Bownik
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000633:toxicity*; D002347:Carps / Q000276:immunology*; D049109:Cell Proliferation / Q000187:drug effects*; D003208:Concanavalin A; D004305:Dose-Response Relationship, Drug; D005098:Exotoxins / Q000633:toxicity*; D008070:Lipopolysaccharides; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D001426:Bacterial Proteins; D005098:Exotoxins; D008070:Lipopolysaccharides; C115218:LukD protein, Staphylococcus aureus; C115217:LukE protein, Staphylococcus aureus; D013778:Tetrazolium Salts; D013844:Thiazoles; D003208:Concanavalin A; C022616:thiazolyl blue