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Luo J, Chen Y, Huang Y, Feng J, Yuan Y, Jian J, Cai S, Yang S. A novel C-type lectin for Litopenaeus vannamei involved in the innate immune response against Vibrio infection. FISH & SHELLFISH IMMUNOLOGY 2023; 135:108621. [PMID: 36803777 DOI: 10.1016/j.fsi.2023.108621] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/11/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
C-type lectins (CTLs), as a member of pattern recognition receptors, play a vital role in the innate immune response of invertebrates to eliminate micro-invaders. In this study, a novel CTL of Litopenaeus vannamei, namely, LvCTL7, was successfully cloned, with an open reading frame of 501 bp and a capability to encode 166 amino acids. Blast analysis showed that the amino acid sequence similarity between LvCTL7 and MjCTL7 (Marsupenaeus japonicus) was 57.14%. LvCTL7 was mainly expressed in hepatopancreas, muscle, gill and eyestalk. Vibrio harveyi can significantly affect LvCTL7 expression level in hepatopancreases, gills, intestines and muscles (p < 0.05). LvCTL7 recombinant protein can bind to Gram-positive bacteria (Bacillus subtilis) and Gram-negative bacteria (Vibrio parahaemolyticus and V. harveyi). It can cause the agglutination of V. alginolyticus and V. harveyi, but it had no effect on Streptococcus agalactiae and B. subtilis. The expression levels of SOD, CAT, HSP 70, Toll 2, IMD and ALF genes in the challenge group added with LvCTL7 protein were more stable than those in the direct challenge group (p < 0.05). Moreover, knockdown of LvCTL7 by double-stranded RNA interference downregulated the expression levels of genes (ALF, IMD and LvCTL5) that protect against bacterial infection (p < 0.05). These results indicated that LvCTL7 had microbial agglutination and immunoregulatory activity, and it was involved in the innate immune response against Vibrio infection in L. vannamei.
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Affiliation(s)
- Junliang Luo
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Yanghui Chen
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Yongxiong Huang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Jiamin Feng
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Yunhao Yuan
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Jichang Jian
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Shuanghu Cai
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China
| | - Shiping Yang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, China.
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Hao P, Han L, Quan Z, Jin X, Li Y, Wu Y, Zhang X, Wang W, Gao C, Wang L, Wang H, Zhang W, Chang Y, Ding J. Integrative mRNA-miRNA interaction analysis associated with the immune response of Strongylocentrotus intermedius to Vibrio harveyi infection. FISH & SHELLFISH IMMUNOLOGY 2023; 134:108577. [PMID: 36773712 DOI: 10.1016/j.fsi.2023.108577] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 11/08/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Strongylocentrotus intermedius is one of the most economically valuable sea urchin species in China and has experienced mass mortality owing to outbreaks of bacterial diseases such as black mouth disease. This has caused serious economic losses to the sea urchin farming industry. To investigate the immune response mechanism of S. intermedius with different tube feet colors in response to Vibrio harveyi infection, we examined the different tube feet-colored S. intermedius under V. harveyi challenge and compared their transcriptome and microRNA (miRNA) profiles using RNA-Seq. We obtained 1813 differentially expressed genes (DEGs), 28 DE miRNAs, and 303 DE miRNA-DEG pairs in different tube feet-colored S. intermedius under V. harveyi challenge. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the most significant DEGs were associated with the Notch signaling and phagosome pathways. The target genes of immune-related miRNAs (miR-71, miR-184, miR-193) and genes (CALM1, SPSB4, DMBT, CSRP1) in S. intermedius were predicted and validated. This study provides insight into the molecular mechanisms that regulate genes involved in the immune response of S. intermedius infected with V. harveyi.
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Affiliation(s)
- Pengfei Hao
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Lingshu Han
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China; Ningbo University, Ningbo, Zhejiang, 315832, PR China
| | - Zijiao Quan
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Xin Jin
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Yuanxin Li
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Yanglei Wu
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Xianglei Zhang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Wenpei Wang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Chuang Gao
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Luo Wang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Heng Wang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Weijie Zhang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Yaqing Chang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China
| | - Jun Ding
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian, Liaoning, 116023, PR China.
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Mo B, Li J, Liao G, Wang L, Fan L. Toxic effects of glyphosate on histopathology and intestinal microflora of juvenile Litopenaeus vannamei. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 255:106399. [PMID: 36680893 DOI: 10.1016/j.aquatox.2023.106399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 06/17/2023]
Abstract
Glyphosate is a widely used broad-spectrum herbicide, its pollution to the surrounding conditions can't be ignored. It has been reported that glyphosate has poisonous impacts on aquatic animals. In this study, juvenile Litopenaeus vannamei (L. vannamei) was exposed to glyphosate, and the lethal concentration 50 (LC50) of glyphosate to juvenile L. vannamei for 48 h was 47.6 mg/L. The histological analysis for intestine and hepatopancreas and the intestinal microorganisms of L. vannamei were evaluated after 48 h of exposure to glyphosate with LC50. The histological analysis results showed that the lumen of hepatic tubules was diffused and deformed, the hepatic tubules were ruptured and intestinal villi were fallen off seriously after exposure to glyphosate for 48 h Moreover, the intestinal microbial composition and structure of L. vannamei were changed, with the abundance of Alphaproteobacteria increased significantly. The abundance of Rhodobacteraceae, Vibrio and Legionella increased, but there was no significant difference. The abundance of Bacillus, Paraburkholderia, Enhydrobacter, Comamonas and Alkanindiges decreased significantly. However, the homeostasis of intestinal microorganisms was destroyed. Phenotypic prediction of the two groups of microorganisms revealed a significant increase in the abundance of Facultatively Anaerobic in the glyphosate challenged group. This study suggested that hepatopancreas and intestinal tissue of L. vannamei were seriously damaged after 48 h of exposure to glyphosate with LC50, and intestinal microbial homeostasis was disrupted.
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Affiliation(s)
- Binhua Mo
- College of Marine Sciences, University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, South China Agricultural University, Guangzhou 510642, China
| | - Jingping Li
- College of Marine Sciences, University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, South China Agricultural University, Guangzhou 510642, China
| | - Guowei Liao
- College of Marine Sciences, University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, South China Agricultural University, Guangzhou 510642, China
| | - Lei Wang
- Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, School of Life Sciences, Institute of Modern Aquaculture Science and Engineering (IMASE), South China Normal University, Guangzhou 510631, China.
| | - Lanfen Fan
- College of Marine Sciences, University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, South China Agricultural University, Guangzhou 510642, China; Research Center for Green Development of Agriculture, South China Agricultural University, Guangzhou 510642, China.
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Dai L, Xiong Z, Hou D, Wang Y, Li T, Long X, Chen H, Sun C. Pathogenicity and transcriptome analysis of a strain of Vibrio owensii in Fenneropenaeus merguiensis. FISH & SHELLFISH IMMUNOLOGY 2022; 130:194-205. [PMID: 36087819 DOI: 10.1016/j.fsi.2022.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Vibrio is an important conditional pathogen in shrimp aquaculture. This research reported a dominant bacteria strain E1 isolated from a shrimp tank with the method of biofloc culture, which was further identified as Vibrio owensii. To understand the interaction between V. owensii and the host shrimp, we studied the pathogenicity of the V. owensii and the molecular mechanisms of the Fenneropenaeus merguiensis immunity during the Vibrio invasion. Drug susceptibility tests showed that V. owensii was resistant to antibiotics streptomycin oxacillin, tetracycline, minocycline, and aztreonam, but highly sensitive to cefazolin, cefotaxime, and ciprofloxacin, and moderately sensitive to cefotaxime, ampicillin, and piperacillin. Lethal concentration 50 (LC50) test was performed to evaluate the toxicity of V. owensii to F. merguiensis. The LC50 of V. owensii infected F. merguiensis after 24, 48, 72, 96, 120, 144 and 168 h were 1.21 × 107, 1.68 × 106, 6.36 × 105, 2.15 × 105, 7.58 × 104, 5.55 × 104 and 4.33 × 104 CFU/mL. In order to explore the molecular response mechanism of F. merguiensis infected with V. owensii, the hepatopancreas of F. merguiensis were sequenced at 24 hpi and 48 hpi, and a total 40,181 of unigenes were obtained. Through comparative transcriptomic analysis, 86 differentially expressed genes (DEGs) (including 38 up-regulated DEGs, and 48 down-regulated DEGs) and 305 DEGs (including 150 up-regulated DEGs, and 155 down-regulated DEGs) were identified at 24 hpi and 48 hpi, respectively. Annotation and classification analysis of these 391 DEGs showed that most of the DEGs were annotated to metableolic and immune pathways, which indicated that F. merguiensis responded to the invasion through the regulation of material metableolism and immune system genes during V. owensii infection. In the KEGG enrichment analysis, some pathways related to immune response were significantly influenced by V. owensii infection, including phagosome, MAPK signalling pathway and PI3K-Akt signalling pathway. In addition, some pathways related to the warburg effect were also significantly enriched after V. owensii infection, including pyruvate metableolism, glycolysis/gluconeogenesis, and citrate cycle (TAC cycle). Further analysis showed that C-type lectins and ficolin were also play important roles in the immune response of F. merguiensis against V. owensii infection. The current research preliminarily revealed the immune response of F. merguiensis to V. owensii infection at the molecular level, which provided valuable information to further understand the disease control and the interaction between shrimp and Vibrio.
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Affiliation(s)
- Linxin Dai
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Zhiwang Xiong
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Danqing Hou
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Yue Wang
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Ting Li
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Xinxin Long
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Haozhen Chen
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Chengbo Sun
- College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, Guangdong, China; Guangdong Provincial Laboratory of Southern Marine Science and Engineering, Zhanjiang, Guangdong, China.
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Chen J, Wang H, Yuan H, Hu N, Zou F, Li C, Shi L, Tan B, Zhang S. Effects of dietary Clostridium autoethanogenum protein on the growth, disease resistance, intestinal digestion, immunity and microbiota structure of Litopenaeus vannamei reared at different water salinities. Front Immunol 2022; 13:1034994. [PMID: 36275652 PMCID: PMC9585349 DOI: 10.3389/fimmu.2022.1034994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 09/21/2022] [Indexed: 12/04/2022] Open
Abstract
The shortage of fishmeal (FM) resources limits the healthy development of aquaculture. Developing new protein sources to replace FM in aquatic feeds is an effective measure to alleviate this situation. However, the application effect of new protein sources is greatly affected by water salinity, which is an important parameter of aquaculture. In this study, the growth, disease resistance, and intestinal digestion, immunity, and microbiota structure of Litopenaeus vannamei (initial weight: 0.38 ± 0.01 g) fed on Clostridium autoethanogenum protein (CAP) or not at three different water salinities (15 ‰, 30 ‰, and 45 ‰) were compared, aiming to explore the effects of dietary CAP on shrimp when suffering different salinity stresses. The results showed that the growth performance, feed utilization, and survival rate (SR) after pathogen challenge of L. vannamei could be significantly improved by dietary CAP when compared with the control at the same salinity and they were also significantly affected by salinity changes when L. vannamei was fed on the same protein source. With the increase in salinity, obvious upregulation was observed in the activities and gene expression of digestive enzymes both in L. vannamei fed on FM and CAP, with significantly higher levels in L. vannamei fed on CAP than in those fed on FM at the same salinity. Meanwhile, the expression levels of immune genes in the CAP group were significantly higher than those in the FM group at different salinities. The intestinal microbiota analysis showed that CAP could increase the relative abundance of beneficial bacteria and decrease the relative abundance of harmful bacteria in the intestine of L. vannamei at the phylum, family, and genus levels, and it was more affected by salinity changes when compared with FM. Besides, the changes in salinity and protein sources led to different changes in the intestinal microflora function of L. vannamei. In sum, this study indicated that CAP could improve the growth, disease resistance, digestive capacity, and intestinal microflora of L. vannamei with a much more intense immune response and enhance its ability to cope with salinity stress.
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Affiliation(s)
- Jian Chen
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Hongming Wang
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Hang Yuan
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Naijie Hu
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Fangqi Zou
- Technology R&D Department, Beijing Shoulang Bio-Technology Co., Ltd., Beijing, China
| | - Chongyang Li
- Technology R&D Department, Beijing Shoulang Bio-Technology Co., Ltd., Beijing, China
| | - Lili Shi
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Beiping Tan
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
- Key Laboratory of Aquatic, Livestock and Poultry Feed Science and Technology in South China, Ministry of Agriculture, Zhanjiang, China
- Aquatic Animal Nutrition and Feed Laboratory, Aquatic Animals Precision Nutrition and High Efficiency Feed Engineering Research Center of Guangdong Province, Zhanjiang, China
| | - Shuang Zhang
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
- Key Laboratory of Aquatic, Livestock and Poultry Feed Science and Technology in South China, Ministry of Agriculture, Zhanjiang, China
- Aquatic Animal Nutrition and Feed Laboratory, Aquatic Animals Precision Nutrition and High Efficiency Feed Engineering Research Center of Guangdong Province, Zhanjiang, China
- *Correspondence: Shuang Zhang,
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Viana JT, Rocha RDS, Maggioni R. Structural and functional diversity of lectins associated with immunity in the marine shrimp Litopenaeusvannamei. FISH & SHELLFISH IMMUNOLOGY 2022; 129:152-160. [PMID: 36058435 DOI: 10.1016/j.fsi.2022.08.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
Lectins are important pattern recognition receptors (PRRs) and their immunological action is related to the recognition of glycans present in the pathogen cells surface. The lectins described for Litopenaeus vannamei are divided into C-type, L-type and galectin, which are mainly expressed in hepatopancreas and hemocytes. They are involved in several immune response pathways, such as phagocytosis, hemocytes recruitment, prophenoloxidase activation, and gene regulation. Although lectins have multiple immune functions, most experimental challenges focus only on WSSV and Vibrio sp. This article is a detailed review on the role of lectins in L. vannamei immune system, bringing together information on molecular structure, temporal and special expression and immune function, highlighting the wide participation of these molecules in shrimp innate immune system.
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Affiliation(s)
- Jhonatas Teixeira Viana
- Center for the Diagnosis of Diseases of Aquatic Organisms, Marine Sciences Institute, Federal University of Ceará, 60165-081, Fortaleza, CE, Brazil.
| | - Rafael Dos Santos Rocha
- Center for the Diagnosis of Diseases of Aquatic Organisms, Marine Sciences Institute, Federal University of Ceará, 60165-081, Fortaleza, CE, Brazil.
| | - Rodrigo Maggioni
- Center for the Diagnosis of Diseases of Aquatic Organisms, Marine Sciences Institute, Federal University of Ceará, 60165-081, Fortaleza, CE, Brazil.
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Li Y, Pan L, Yu J. The injection of one recombinant C-type lectin (LvLec) induced the immune response of hemocytes in Litopenaeus vannamei. FISH & SHELLFISH IMMUNOLOGY 2022; 124:324-331. [PMID: 35429625 DOI: 10.1016/j.fsi.2022.04.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/06/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
To explore the immune function of C-type lectin in shrimp, one recombinant C-type lectin (LvLec) was injected into Litopenaeus vannamei. There were four treatments in the experiment: saline group (as control group), recombinant C-type lectin group (LvLec, 1 mg mL-1), Vibrio harveyi group (V. harveyi, 106 cfu mL-1) and recombinant C-type lectin combined with Vibrio harveyi group (LvLec + V. harveyi, 1 mg mL-1 + 106 cfu mL-1). The sampling time was set at 0, 3, 6, 9, 12, 24 h after the injection. The results showed that the total hemocyte count decreased significantly and the phagocytic activity improved notably after the injection of LvLec, V. harveyi or LvLec + V. harveyi. Prophenoloxidase (proPO) activity decreased, while phenoloxidase (PO) activity increased and the changing degree of each group exhibited a significant difference. The hemagglutinating activity and bacteriolytic activity improved significantly, while the antimicrobial activity did not show a remarkable change in all of the groups. There were also changes that occurred in the levels of second messengers (cAMP, cGMP) and protein kinase (PKA, PKG). After the injection of LvLec, V. harveyi or LvLec + V. harveyi, the concentration of cGMP and PKA increased significantly, while the concentration of cAMP and PKG did not change remarkably. The results above suggested that rLvLec could induce nonspecific immune response, including phagocytosis, release of PO, hemagglutination and bacteriolysis through cGMP-PKA pathway in vivo.
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Affiliation(s)
- Yaobing Li
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Luqing Pan
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China.
| | - Jinhong Yu
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
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