Inhibition of chemiluminescent response of olive flounder Paralichthys olivaceus phagocytes by the scuticociliate parasite Uronema marinum.
Experiments were conducted to evaluate the in vitro capacity of the scuticociliatian parasite Uronema marinum to inhibit chemiluminescence (CL) of olive flounder Paralichthys olivaceus phagocytes. Luminol-enhanced CL was used to measure the production of reactive oxygen intermediates (ROIs) generated by respiratory bursts of phagocytes using zymosan as a stimulant. Cytotoxic and antioxidative activities of excretory-secretory (ES) products of the parasite were evaluated as well. Live U. marinum and its ES products had a negative and dose-dependent effect on luminol-enhanced CL responses of zymosan-stimulated phagocytes of olive flounder. After CL assay, the number of phagocytes showing viability was significantly reduced in the cells incubated with live U. marinum at ratios of 2:1 and 1:1 phagocytes:ciliates or ES products with 0.3 mg protein ml(-1) compared to controls. Lysis of phagocytes by exposure to ES products was observed also. ES products from U. marinum showed considerably high activities of superoxide dismutase (SOD) and catalase. The results of this study suggest that U. marinum can protect itself against host's phagocytes mediated oxidative damage by destroying phagocytes and scavenging ROIs.
Kwon
Se Ryun
SR
Department of Aquatic Life Medicine, Pukyong National University, Pusan 608-737, Korea.
Kim
Chun Soo
CS
Chung
Joon Ki
JK
Lee
Hyung Ho
HH
Kim
Ki Hong
KH
D000818:Animals; D002374:Catalase / Q000378:metabolism; D016798:Ciliophora / Q000737:chemistry* / Q000276:immunology; D016770:Ciliophora Infections / Q000276:immunology / Q000469:parasitology / Q000662:veterinary; D004306:Dose-Response Relationship, Immunologic; D005393:Fish Diseases / Q000276:immunology / Q000469:parasitology; D005432:Flounder / Q000276:immunology* / Q000469:parasitology; D016166:Free Radical Scavengers; D008163:Luminescent Measurements; D010586:Phagocytes / Q000276:immunology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016897:Respiratory Burst; D013482:Superoxide Dismutase / Q000378:metabolism
D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D002374:Catalase; D013482:Superoxide Dismutase