Reduction of adhesion properties of Ruditapes philippinarum hemocytes exposed to Vibrio tapetis.
Vibrio tapetis is the causative agent of brown ring disease (BRD), which affects a species of clam, Ruditapes philippinarum. After incubation with V. tapetis, hemocytes lose filopods and become rounded, indicating cytotoxic activity of the bacterium. To rapidly quantify this cytotoxicity, a flow-cytometry test was developed based on the capacity of V. tapetis to inhibit adhesion of clam hemocytes to plastic. Several bacteria:hemocyte ratios, the cytotoxicity of other Vibrio spp. pathogenic to bivalves, and that of various V. tapetis isolates were tested. Inhibition of adherence is detectable with as few as 5 bacteria per hemocyte. The greater cytotoxic activity of V. tapetis compared to that of V. splendidus and V. pectenicida suggests a specific pathogenicity of V. tapetis to R. philippinarum hemocytes. Although all V. tapetis isolates inhibited adhesion, significant variations in cytotoxicity among isolates was demonstrated.
Choquet
Gwénaëlle
G
Laboratoire des Sciences de l'Environnement Marin (LEMAR), Institut Universitaire Européen de la Mer (IUEM-UBO), Place Copernic Technopôle Brest-Iroise, 29280 Plouzané, France.
Soudant
Philippe
P
Lambert
Christophe
C
Nicolas
Jean-Louis
JL
Paillard
Christine
C
D000704:Analysis of Variance; D000818:Animals; D049872:Bivalvia / Q000378:metabolism* / Q000382:microbiology*; D002448:Cell Adhesion; D005060:Europe; D005434:Flow Cytometry; D006434:Hemocytes / Q000378:metabolism*; D012623:Seawater; D012680:Sensitivity and Specificity; D014733:Vibrio / Q000472:pathogenicity*