Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Hubei Hongshan Laboratory, Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China.
Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China.
Fish Shellfish Immunol. 2022 Aug;127:572-584. doi: 10.1016/j.fsi.2022.07.004. Epub 2022 Jul 5.
Combination of antimicrobial proteins and nanomaterials provides a platform for the development of immunopotentiators. Oral administration of immunopotentiators can significantly enhance the immunity of organisms, which provides ideas for disease prevention. In this study, we confirmed that nanoparticles CMCS-20a can efficiently prevent grass carp reovirus (GCRV) infection. Firstly, we verified that CiCXCL20a is involved in the immune responses post GCRV challenge in vivo and alleviates the cell death post GCRV challenge in CIK cells. Then, we prepared nanoparticles CMCS-20a using carboxymethyl chitosan (CMCS) loaded with grass carp (Ctenopharyngodon idella) CXCL20a (CiCXCL20a). Meanwhile, we confirmed nanoparticles CMCS-20a can alleviate the degradation in intestine. Subsequently, we added it to the feed by low temperature vacuum drying method and high temperature spray drying method, respectively. Grass carp were oral administration for 28 days and challenged by GCRV. Low temperature vacuum drying group (LD-CMCS-20a) significantly improve grass carp survival rate, but not high temperature spray drying group (HD-CMCS-20a). To reveal the mechanisms, we investigated the serum biochemical indexes, intestinal mucus barrier, immune gene regulation and tissue damage. The complement component 3 content, lysozyme and total superoxide dismutase activities are highest in LD-CMCS-20a group. LD-CMCS-20a effectively attenuates the damage of GCRV to the number of intestinal villous goblet cells and mucin thickness. LD-CMCS-20a effectively regulates mRNA expressions of immune genes (IFN1, Mx2, Gig1 and IgM) in spleen and head kidney tissues. In addition, LD-CMCS-20a obviously alleviate tissue lesions and viral load in spleen. These results indicated that the nanoparticles CMCS-20a can enhance the disease resistance of fish by improving their immunity, which provides a new perspective for fish to prevent viral infections.
抗菌蛋白和纳米材料的结合为免疫增强剂的开发提供了一个平台。免疫增强剂的口服给药可以显著增强生物体的免疫力，为疾病预防提供了思路。在这项研究中，我们证实纳米粒子 CMCS-20a 可以有效地预防草鱼呼肠孤病毒（GCRV）感染。首先，我们验证了 CiCXCL20a 参与了体内 GCRV 攻毒后的免疫反应，并减轻了 GCRV 攻毒后 CIK 细胞的细胞死亡。然后，我们使用负载草鱼（Ctenopharyngodon idella）CXCL20a（CiCXCL20a）的羧甲基壳聚糖（CMCS）制备了纳米粒子 CMCS-20a。同时，我们证实纳米粒子 CMCS-20a 可以减轻肠道的降解。随后，我们分别通过低温真空干燥法和高温喷雾干燥法将其添加到饲料中。草鱼经口给药 28 天，然后用 GCRV 攻毒。低温真空干燥组（LD-CMCS-20a）显著提高了草鱼的存活率，但高温喷雾干燥组（HD-CMCS-20a）没有。为了揭示其机制，我们研究了血清生化指标、肠道黏液屏障、免疫基因调控和组织损伤。LD-CMCS-20a 组的补体成分 3 含量、溶菌酶和总超氧化物歧化酶活性最高。LD-CMCS-20a 有效减轻了 GCRV 对肠绒毛杯状细胞数量和黏液厚度的损害。LD-CMCS-20a 有效调节了脾和头肾组织中免疫基因（IFN1、Mx2、Gig1 和 IgM）的 mRNA 表达。此外，LD-CMCS-20a 明显减轻了脾组织病变和病毒载量。这些结果表明，纳米粒子 CMCS-20a 通过提高鱼类的免疫力增强了鱼类的抗病能力，为鱼类预防病毒感染提供了新的视角。
