Aquatic Animal Health and Therapeutics Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
Aquatic Animal Health and Therapeutics Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia; Department of Veterinary Laboratory Diagnostic, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
Dev Comp Immunol. 2024 Dec;161:105253. doi: 10.1016/j.dci.2024.105253. Epub 2024 Aug 19.
The pathogen recognition system involves receptors and genes that play a crucial role in activating innate immune response in brown-marbled grouper (Epinephelus fuscoguttatus) as a control agent against various infections including vibriosis. Here, we report the molecular cloning of partial open reading frames, sequences characterization, and expression profiles of Pattern Recognition Receptors (PRRs) in brown-marbled grouper. The PRRs, namely pglyrp5, tlr5, ctlD, and ctlE in brown-marbled grouper, possess conserved domains and showed shared evolutionary relationships with other fishes, humans, mammals, birds, reptilians, amphibians, and insects. In infection experiments, up to 50% mortality was found in brown-marbled grouper fingerlings infected with Vibrio alginolyticus compared to 27% mortality infected Vibrio parahaemolyticus and 100% survival of control groups. It is also demonstrated that all four PRRs had higher expression in samples infected with V. alginolyticus compared to V. parahaemolyticus. This PRRs gene expression analysis revealed that all four PRRs expressed rapidly at 4-h post-inoculation even though the Vibrio count was only detected earliest at 12-h post-inoculation in samples. The highest expression recorded was from V. alginolyticus inoculated fish spleen with up to 73-fold change for pglyrp5 gene, followed by 14 to 38-fold expression for the same treatment in spleen, head kidney, and blood samples for other PRRs, namely tlr5, ctlD, and ctlE genes. Meanwhile less than a 10% increase in expression of all four genes was detected in spleen, head kidney, and blood samples inoculated with V. parahaemolyticus. These findings indicated that pglyrp5, tlr5, ctlD, and ctlE play important roles in the early immune response to vibriosis infected, brown-marbled grouper fingerlings.
病原体识别系统涉及受体和基因，这些受体和基因在激活斜带石斑鱼（Epinephelus fuscoguttatus）的固有免疫反应方面发挥着关键作用，可作为控制各种感染（包括弧菌病）的手段。在这里，我们报告了斜带石斑鱼部分开放阅读框的分子克隆、序列特征和模式识别受体（PRRs）的表达谱。PRRs 如斜带石斑鱼中的 pglyrp5、tlr5、ctlD 和 ctlE，具有保守结构域，并与其他鱼类、人类、哺乳动物、鸟类、爬行动物、两栖动物和昆虫具有共同的进化关系。在感染实验中，与感染副溶血弧菌的斜带石斑鱼鱼苗 27%的死亡率相比，感染溶藻弧菌的鱼苗死亡率高达 50%，而对照组的死亡率为 100%。实验还表明，与感染副溶血弧菌相比，所有四种 PRRs 在感染溶藻弧菌的样本中表达更高。该 PRRs 基因表达分析表明，所有四种 PRRs 在接种后 4 小时迅速表达，尽管在样本中最早仅在接种后 12 小时检测到弧菌计数。记录到的最高表达来自感染溶藻弧菌的鱼脾脏，pglyrp5 基因的变化高达 73 倍，其次是相同处理下脾脏、头肾和血液样本中 tlr5、ctlD 和 ctlE 基因的 14 到 38 倍表达。同时，在感染副溶血弧菌的脾脏、头肾和血液样本中，所有四种基因的表达仅增加了不到 10%。这些发现表明，pglyrp5、tlr5、ctlD 和 ctlE 在斜带石斑鱼鱼苗对弧菌感染的早期免疫反应中发挥重要作用。
