论文部分内容阅读
鲑鱼隐鞭虫病的病原为Cryptobiasalmositica。据报道,北美西海岸的所有大西洋鲑(Oncorhynchusspp.)均有该虫的寄生。该病除了通常情况下经河流中的水蛭传播外,在特定的条件下可直接经鱼类传播。鲑隐鞭虫病的临床症状包括贫血、食欲减退、脾脏肿大、全身性水肿、腹水性腹胀。被感染的鱼类需要付出巨大的能量代价,表现出明显的新陈代谢及游泳功能的衰退。鱼体对缺氧相当敏感,免疫系统也受到抑制。鱼类对隐鞭虫病的感染严重程度和死亡率可因鱼种而存在差异。预防感染的有效策略包括选育抗隐鞭虫的新品种,“抗隐鞭虫感染”在遗传上是孟德尔显性遗传。在抗隐鞭虫的鱼体内,虫体可被宿主免疫系统的“补体旁路途径”所裂解。在“隐鞭虫耐受性鱼”(处于感染状态但未发病)的血液中存在一种天然的抗蛋白酶———α2巨球蛋白,可以中和分泌的金属蛋白酶(毒力因子)。因此,繁殖转基因“隐鞭虫耐受性”鲑鱼是一种很好的选择,而无需通过疫苗和药物来治疗隐鞭虫病。康复后的鱼体具有对该病的免疫保护力,因而,利用这一特点采取疫苗免疫也是防治隐鞭虫病的另一种策略。我们所研制的致弱疫苗单一剂量免疫鱼体可获得至少两年的免疫保护。免疫保护机制包括产生“抗体结合补体”、强化吞噬作用及细胞介导的细胞毒作用。氯化氮氨菲啶是防治隐鞭虫病的有效药物,它通过溶解虫体而杀灭寄生虫,也可在线粒体中富集,显著影响有氧呼吸的顺利进行并造成线粒体的损伤。通过药物与抗体连接可以显著增强药效,这种利用“免疫化学疗法”控制鲑隐鞭虫病的策略,其优点在于减小了药物剂量,因而大大降低了化学治疗所引起的副作用。对于食用性鱼类而言,减少药物在鱼体的富集符合食品安全的需要
Cryptobiasalmositica is the causative agent of salmonella. It is reported that all the Atlantic salmon on the west coast of North America (Oncorhynchusspp.) Are parasitic parasites. In addition to the disease usually transmitted by leeches in rivers, it can be transmitted directly by fish under specific conditions. Clinical symptoms of salivary cryptosis include anemia, loss of appetite, enlargement of the spleen, generalized edema, and abdominal bloating. Infected fish need to pay a huge energy price, showing a clear metabolic and swimming decline. Fish are quite sensitive to hypoxia, and the immune system is also suppressed. The severity of the infection and the mortality of fish against whipworm may vary according to species of fish. Effective strategies to prevent infection include the breeding of new varieties of anti-whipworm, “anti-whipworm infection” is genetically Mendelian dominant inheritance. In the anti-whipworm fish, parasites can be lysed by the “complement bypass pathway” of the host’s immune system. In the blood of “whipworm-resistant fish” (in an infected but not diseased) blood, there is a natural protease called α2 macroglobulin that neutralizes the secreted metalloproteinase (virulence factor). Therefore, the breeding of transgenic “whipworm-tolerant” salmon is a good option, without the need for vaccination and drugs for the treatment of whipworm disease. After the rehabilitation of the fish has the immune protection of the disease, therefore, the use of this feature to take vaccination is another strategy for the treatment of whipworm disease. We have developed a single dose of attenuated vaccine immunized fish receive at least two years of immune protection. Immunoprotection mechanisms include the production of “antibody-bound complement,” enhanced phagocytosis and cell-mediated cytotoxicity. Ampicillin chloride is an effective drug for the treatment of whipworm disease. It can kill parasites by dissolving parasites and can also be enriched in mitochondria, which significantly affects aerobic respiration and mitochondrial damage. Pharmacological effects can be significantly enhanced by drug-antibody conjugation. This strategy of using “immunochemotherapy” to control salmonella cryptococcosis has the advantage of reducing the dose of the drug and thus greatly reducing the side effects caused by chemotherapy. For edible fish, reducing the need for enrichment of the drug in fish is in line with food safety