Effects of large dosage of beta-carotene on anti viral immune function in Japanese parrotfish (Oplegnathus fasciatus)

从日本鹦嘴鱼（Oplegnathus fasciatus）制备脾淋巴细胞，并与100 μ g/ml结合于Sepharose 4 B珠的伴刀豆球蛋白A孵育48小时，然后收集刺激的细胞上清液。将Thyoglycolate诱导的同种异体腹膜巨噬细胞（Pmphi）与或不与刺激的细胞上清液一起孵育。然后，测定Pmphi对灭活酵母的吞噬活性和过氧化物酶的产生。刺激细胞上清液增加吞噬活性和过氧化物酶的生产同种异体Pmphi。这些刺激的细胞上清液在56 ℃加热30 min或在pH 2缓冲液中透析24 h后，其活性完全丧失，类似于IFN_2<gamma>。刺激细胞上清不能增加异源小鼠Pmphi的吞噬活性和过氧化物酶的产生.这些结果表明日本鹦嘴鱼脾淋巴细胞能在体外产生一种巨噬细胞活化因子，这种因子可能是IFN_（？<gamma>）日本鹦嘴鱼幼虫被提供了β-胡萝卜素补充饲料（β-胡萝卜素Plemented轮虫和颗粒：5,000 μ g/100 g）12个月。结果表明：（1）添加β-胡萝卜素组的脾淋巴细胞产生IFN_2<gamma>的能力高于对照组;（2）添加β-胡萝卜素组的绵羊红细胞抗体产生能力高于对照组;（3）添加β-胡萝卜素组的Pmphi对灭活酵母菌的吞噬能力高于对照组;（4）添加β-胡萝卜素组的Ht、Hb和血清蛋白值与对照组无差异。高剂量的β-胡萝卜素没有引起鱼的疾病和生长障碍。这些发现表明，在日本鹦嘴鱼养殖中使用添加β-胡萝卜素的饲料可以产生对传染病具有高抗性的鱼。

Spleen lymphocytes were prepared from Japanese parrotfish (Oplegnathus fasciatus) and incubated with 100mug/ml of Concanavalin A bound to Sepharose 4B beads for 48h, and then the stimulated cell supernatants were collected. Thyoglycolate induced, allogenic, peritoneal macrophages (Pmphi) were incubated with or without stimulated cell supernatants. Then, the phagocytic activity of Pmphi against inactivated yeast and peroxidase production were measured. Stimulated cell supernatants increased the phagocytic activity and the peroxidase production of allogenic Pmphi. The activities of these stimulated cell supernatants were lost completely when they were heated at 56ﾟC for 30min or dialyzed against a pH 2 buffer for 24h-similar to IFN_<gamma>. Stimulated cell supernatants did not increase phagocytic activity and peroxidase production of heterogenic mouse Pmphi.These finding suggest that the spleen lymphocytes of Japanese parrotfish can produce a macrophage activating factor in vitro with concanavalin A bound to Sepharose 4B beads, and that this factor may be IFN_<gamma>.In next experiment, Japanese parrotfish larvae were served the beta-carotene supplemented diets (BETA-carotene Plemented rotifer and moist-pellet : 5,000 mug/100g) for 12 months. Then, the immune function were examined.1) The spleen lymphocyte from beta-carotene supplemented group produced more IFN_<gamma> than control group.2) Antibody production for sheep red blood cell in BETA-carotene supplemented group were higher than control group.3) Phagocytic activity of Pmphi against inactivated yeast in beta-carotene supplemented group were were higher than contorol group.4) The Ht, Hb and serum protein value were not difference in both groups. Illness and growth obstruction of fish were not observed by the high dosage of beta-carotene.These finding suggest that the using of beta-carotene supplemented diets for aquaculture of Japanese parrotfish can produce high resistance fish for infectious disease.