Several researches reported that piscidin members of teleosts owned strong antiparasitic activity. Cryptocaryon irritans, a type of ectoparasite, could infect most of the marine teleosts. Larimichthys crocea could severely suffer from marine white spot disease caused by C. irritans, and their mortality rate was significantly high. Concentrating on this problem, we have done many related works. Piscidin 5 like (termed Lc-P5L) was another piscidin member isolated from a comparative transcriptome of C. irritans-immuned L. crocea. In the paper, quantitative Real-time PCR (qRT-PCR) showed Lc-P5L was upregulated in examined tissues, including gill, head kidney, muscle, liver, spleen and intestine after challenged by C. irritans, the significant upregulation time was in accordance to key developmental stages of C. irritans, which implied different infection stages could result in host immune response. Furthermore, using microscope techniques, we observed theronts or trophonts became weakly motile, cilia became detached, cells were out of shape, membranes eventually lysed in different cell positions and cytoplasmic contents leaked. Laser confocal scanning microscope (LCSM) observed theronts macronucleus grew swell and depolymerized after treated by recombinant Lc-P5L (rLc-P5L). Data suggested rLc-P5L was significantly lethal to C. irritans, and the death state of the parasite incubated with rLc-P5L was remarkably similar to other piscidin members or other antiparasitic peptides (APPs). Thus, these data provided new insights into L. crocea immunity against C. irritans and potential of rLc-P5L as a therapeutic agent against pathogen invasion.

几项研究报告称，硬骨鱼的 piscidin 成员具有很强的抗寄生虫活性。Cryptocaryon irritans是一种外寄生虫，可以感染大多数海洋硬骨鱼。Larimichthys crocea可严重感染由C. irritans引起的海洋白斑病，死亡率显着较高。针对这个问题，我们做了很多相关的工作。Piscidin 5 样 (称为Lc-P5L ) 是另一种piscidin成员，从C. irritans免疫的大黄鱼的比较转录组中分离出来。在论文中，定量实时 PCR (qRT-PCR) 显示Lc-P5L在检查的组织中，包括鳃，头肾，肌肉，肝，脾和肠受到挑战后上调C. irritans，所述显著上调时间为根据到的关键发育阶段C. irritans，这暗示不同感染阶段可能会导致宿主免疫反应。此外，使用显微镜技术，我们观察到乳突或滋养体运动减弱，纤毛脱落，细胞变形，膜最终在不同细胞位置裂解，细胞质内容物泄漏。激光共聚焦扫描显微镜（LCSM）观察到重组Lc-P5L（rLc-P5L）处理后的乳突巨核膨胀并解聚。数据表明 rLc-P5L 对C. irritans具有显着致死性，并且与 rLc-P5L 一起孵育的寄生虫的死亡状态与其他鱼精蛋白成员或其他抗寄生虫肽 (APP) 非常相似。因此，这些数据提供的新的见解L.黄鱼针对免疫C. irritans和RLC-P5L的电位作为对抗病原体侵入的治疗剂。