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Yang Z, Zhang Y, Zhao Q, Du S, Huang X, Wu R, Yan Q, Han X, Wen Y, Cao SJ. HbpA from Glaesserella parasuis induces an inflammatory response in 3D4/21 cells by activating the MAPK and NF-κB signalling pathways and protects mice against G. parasuis when used as an immunogen. Vet Res 2024; 55:93. [PMID: 39075605 PMCID: PMC11285476 DOI: 10.1186/s13567-024-01344-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 06/17/2024] [Indexed: 07/31/2024] Open
Abstract
Glaesserella parasuis is usually a benign swine commensal in the upper respiratory tract, but virulent strains can cause systemic infection characterized by pneumonia, meningitis, and fibrinous polyserositis. The intensive pulmonary inflammatory response following G. parasuis infection is the main cause of lung injury and death in pigs. Vaccination has failed to control the disease due to the lack of extended cross-protection. Accumulating evidence indicates that the heme-binding protein A (HbpA) is a potential virulence determinant and a promising antigen candidate for the development of a broader range of vaccines. However, it is not yet known whether HbpA contributes to G. parasuis virulence or has any potential immune protective effects against G. parasuis. Here, we show that HbpA can induce the transcription and secretion of proinflammatory cytokines (IL-6, TNF-α, and MCP-1) in porcine alveolar macrophages (PAM, 3D4/31). The HbpA protein is recognized by Toll-like receptors 2 and 4 on 3D4/21 macrophages, resulting in the activation of MAP kinase and NF-κB signalling cascades and the transcription and secretion of proinflammatory cytokines. HbpA contributes to virulence and bacterial pulmonary colonization in C57BL/6 mice and plays a role in adhesion to host cells and evasion of the bactericidal effect of pulmonary macrophages. In addition, mice immunized with HbpA were partially protected against challenge by G. parasuis SC1401. The results suggest that HbpA plays an important role in the pathogenesis of disease caused by G. parasuis and lay a foundation for the development of a subunit or chimeric anti-G. parasuis vaccine.
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Affiliation(s)
- Zhen Yang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yiwen Zhang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qin Zhao
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Senyan Du
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiaobo Huang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Rui Wu
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qigui Yan
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinfeng Han
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yiping Wen
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
| | - San-Jie Cao
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
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2
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Du T, Xiong S, Wang L, Liu G, Guan Q, Xie M, Xiong T, Huang J. Two-stage fermentation of corn and soybean meal mixture by Bacillus subtilis and Lactobacillus acidophilus to improve feeding value: optimization, physicochemical property, and microbial community. Food Sci Biotechnol 2024; 33:1207-1219. [PMID: 38440689 PMCID: PMC10908692 DOI: 10.1007/s10068-023-01426-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/16/2023] [Accepted: 08/28/2023] [Indexed: 03/06/2024] Open
Abstract
Microbial treatment can reduce the antinutritional factors and allergenic proteins in corn-soybean meal mixture (CSMM), but the role of the microbial community in hypoallergenicity and digestibility during the fermentation process remains unclear. Therefore, the fermentation strains of Bacillus and LAB were determined, and the compatibility and fermentation process of two-stage solid fermentation composite bacteria were optimized, and the dynamic changes in physicochemical property and microbial community during two-stage fermentation were investigated. Results showed that Bacillus subtilis NCUBSL003 and Lactobacillus acidophilus NCUA065016 were the best fermentation combinations. The optimal fermentation conditions were inoculum 7.14%, solid-liquid ratio of 1:0.88 and fermentation time of 74.30 h. The contents of TI, β-conglycinin and glycinin decreased significantly after fermentation. Besides, TCA-SP, small peptides and FAA increased. Bacillus and Lactobacillus were the main genera. Pathogenic bacteria genera were inhibited effectively. This study suggests the feasibility of two-stage fermentation in improving the nutrient values and safety of the CSMM. Supplementary Information The online version contains supplementary material available at 10.1007/s10068-023-01426-7.
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Affiliation(s)
- Tonghao Du
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047 China
- School of Food Science & Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang, 330047 Jiangxi China
| | - Shijin Xiong
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047 China
- School of Food Science & Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang, 330047 Jiangxi China
| | - Li Wang
- Institute of Agricultural Products Processing, Jiangxi Academy of Agricultural Sciences, 602 Nanlian Road, Nanchang, 330200 Jiangxi China
| | - Guangxian Liu
- Institute of Agricultural Products Processing, Jiangxi Academy of Agricultural Sciences, 602 Nanlian Road, Nanchang, 330200 Jiangxi China
| | - Qianqian Guan
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047 China
- School of Food Science & Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang, 330047 Jiangxi China
| | - Mingyong Xie
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047 China
- School of Food Science & Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang, 330047 Jiangxi China
| | - Tao Xiong
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047 China
- School of Food Science & Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang, 330047 Jiangxi China
| | - Jinqing Huang
- Institute of Agricultural Products Processing, Jiangxi Academy of Agricultural Sciences, 602 Nanlian Road, Nanchang, 330200 Jiangxi China
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Deng X, Li S, Zhu Y, Yu B, Zhang J, Fang Q, Li Z, Chen H, Zhou H. Assessment of the Macrophage Scavenger Receptor CD163 in Mediating Glaesserella parasuis Infection of Host Cells. Vet Sci 2023; 10:vetsci10030235. [PMID: 36977274 PMCID: PMC10054613 DOI: 10.3390/vetsci10030235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 03/10/2023] [Accepted: 03/19/2023] [Indexed: 03/30/2023] Open
Abstract
The macrophage CD163 surface glycoprotein is a member of the SRCR family class B, which has been identified as the key trigger in host-pathogen interactions, but its specific roles in sensing Glaesserella parasuis (G. parasuis) infection are largely unknown. Here, we investigated porcine CD163 in mediating the adhesion and immune response of G. parasuis using in vitro host-bacteria interaction models. CD163-overexpressing Chinese hamster ovary K1 cells (CHO-K1) showed obvious subcellular localization in the cytoplasm, especially in the cytomembrane. Although detection using scanning electron microscopy (SEM) confirmed the bacterial adhesion, there was no significant difference in the adhesion of G. parasuis to CHO-K1 cells between the presence and absence of CD163. In addition, similar results were observed in 3D4/21 cells. Meanwhile, bindings of G. parasuis to nine synthetic peptides, the bacterial binding motifs within SRCR domains of CD163, were weak based on a solid-phase adhesion assay and agglutination assay. Moreover, CD163 had no effect on the expression of G. parasuis-induced inflammatory cytokines (IL-6, INF-γ, IL-10, IL-4 and TGF-β) in CHO-K1 cells. In conclusion, these findings indicate that porcine CD163 plays a minor role in sensing G. parasuis infection.
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Affiliation(s)
- Xiangwei Deng
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Shuilian Li
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Ying Zhu
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Bo Yu
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Jing Zhang
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Qianhai Fang
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Zhimin Li
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Hongbo Chen
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Huanhuan Zhou
- Laboratory of Genetic Breeding, Reproduction and Precision Livestock Farming & Hubei Provincial Center of Technology Innovation for Domestic Animal Breeding, School of Animal Science and Nutritional Engineering, Wuhan Polytechnic University, Wuhan 430023, China
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Wu J, Nan W, Peng G, Hu H, Xu C, Huang J, Xiao Z. Screening of linear B-cell epitopes and its proinflammatory activities of Haemophilus parasuis outer membrane protein P2. Front Cell Infect Microbiol 2023; 13:1192651. [PMID: 37207184 PMCID: PMC10189045 DOI: 10.3389/fcimb.2023.1192651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 04/11/2023] [Indexed: 05/21/2023] Open
Abstract
Haemophilus parasuis is a commensal organism of the upper respiratory tract of pigs, but virulent strains can cause Glässer's disease, resulting in significant economic losses to the swine industry. OmpP2 is an outer membrane protein of this organism that shows considerable heterogeneity between virulent and non-virulent strains, with classification into genotypes I and II. It also acts as a dominant antigen and is involved in the inflammatory response. In this study, 32 monoclonal antibodies (mAbs) against recombinant OmpP2 (rOmpP2) of different genotypes were tested for reactivity to a panel of OmpP2 peptides. Nine linear B cell epitopes were screened, including five common genotype epitopes (Pt1a, Pt7/Pt7a, Pt9a, Pt17, and Pt19/Pt19a) and two groups of genotype-specific epitopes (Pt5 and Pt5-II, Pt11/Pt11a, and Pt11a-II). In addition, we used positive sera from mice and pigs to screen for five linear B-cell epitopes (Pt4, Pt14, Pt15, Pt21, and Pt22). After porcine alveolar macrophages (PAMs) were stimulated with overlapping OmpP2 peptides, we found that the epitope peptides Pt1 and Pt9, and the loop peptide Pt20 which was adjacent epitopes could all significantly upregulated the mRNA expression levels of IL-1α, IL-1β, IL-6, IL-8, and TNF-α. Additionally, we identified epitope peptides Pt7, Pt11/Pt11a, Pt17, Pt19, and Pt21 and loop peptides Pt13 and Pt18 which adjacent epitopes could also upregulate the mRNA expression levels of most proinflammatory cytokines. This suggested that these peptides may be the virulence-related sites of the OmpP2 protein, with proinflammatory activity. Further study revealed differences in the mRNA expression levels of proinflammatory cytokines, including IL-1β and IL-6, between genotype-specific epitopes, which may be responsible for pathogenic differences between different genotype strains. Here, we profiled a linear B-cell epitope map of the OmpP2 protein and preliminarily analyzed the proinflammatory activities and effects of these epitopes on bacterial virulence, providing a reliable theoretical basis for establishing a method to distinguish strain pathogenicity and to screen candidate peptides for subunit vaccines.
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Affiliation(s)
- Jingbo Wu
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan University, Shaoguan, China
- North Guangdong Pig Breeding Waste Reduction Engineering Technology Center, Shaoguan University, Shaoguan, China
| | - Wenjin Nan
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Pig Breeding Waste Reduction Engineering Technology Center, Shaoguan University, Shaoguan, China
- *Correspondence: Wenjin Nan,
| | - Guoliang Peng
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Pig Breeding Waste Reduction Engineering Technology Center, Shaoguan University, Shaoguan, China
| | - Honghui Hu
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Pig Breeding Waste Reduction Engineering Technology Center, Shaoguan University, Shaoguan, China
| | - Chongbo Xu
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan University, Shaoguan, China
| | - Jianqiang Huang
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan University, Shaoguan, China
| | - Zhengzhong Xiao
- Henry Fok College of Yingdong Biology and Agricultural, Shaoguan University, Shaoguan, China
- North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan University, Shaoguan, China
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JIA YC, CHEN X, ZHOU YY, YAN P, GUO Y, YIN RL, YUAN J, WANG LX, WANG XZ, YIN RH. Application of mouse model for evaluation of recombinant LpxC and GmhA as novel antigenic vaccine candidates of Glaesserella parasuis serotype 13. J Vet Med Sci 2021; 83:1500-1508. [PMID: 34393140 PMCID: PMC8569868 DOI: 10.1292/jvms.21-0298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/30/2021] [Indexed: 11/22/2022] Open
Abstract
Glaesserella parasuis (G. parasuis) has been one of the bacteria affecting the large-scale swine industry. Lack of an effective vaccine has limited control of the disease, which has an effect on prevalence. In order to improve the cross-protection of vaccines, development on subunit vaccines has become a hot spot. In this study, we firstly cloned the lpxC and gmhA genes from G. parasuis serotype 13 isolates, and expressed and purified their proteins. The results showed that LpxC and GmhA can stimulate mice to produce IgG antibodies. Through testing the cytokine levels of interleukin 4 (IL-4), IL-10 and interferon-γ (IFN-γ), it is found that recombinant GmhA, the mixed LpxC and GmhA can stimulate the body to produce Th1 and Th2 immune responses, while recombinant LpxC and inactivated bacteria can only produce Th2 immune responses. On the protection rate for mice, recombinant LpxC, GmhA and the mixture of LpxC and GmhA can provide 50%, 50% and 60% protection for lethal dose of G. parasuis infection, respectively. The partial protection achieved by the recombinant LpxC and GmhA supports their potential as novel vaccine candidate antigens against G. parasuis.
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Affiliation(s)
- Yong C. JIA
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Xin CHEN
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Yuan Y. ZHOU
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Ping YAN
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Ying GUO
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Rong L. YIN
- Research Academy of Animal Husbandry and Veterinary Medicine
Sciences of Jilin Province, Changchun 130062, China
| | - Jing YUAN
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Lin X. WANG
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
| | - Xin Z. WANG
- Liaoning Agricultural Technical College, Yingkou, 115009,
China
| | - Rong H. YIN
- Key Laboratory of Livestock Infectious Diseases in Northeast
China, Ministry of Education, College of Animal Science & Veterinary Medicine,
Shenyang Agricultural University, Shenyang 110866, China
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Costa-Hurtado M, Barba-Vidal E, Maldonado J, Aragon V. Update on Glässer's disease: How to control the disease under restrictive use of antimicrobials. Vet Microbiol 2020; 242:108595. [PMID: 32122599 DOI: 10.1016/j.vetmic.2020.108595] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/20/2020] [Accepted: 01/23/2020] [Indexed: 01/27/2023]
Abstract
Antimicrobials have been commonly used to control bacterial diseases in farm animals. The efficacy of these drugs deterred the development of other control measures, such as vaccines, which are currently getting more attention due to the increased concern about antimicrobial resistance. Glässer's disease is caused by Glaesserella (Haemophilus) parasuis and affects pork production around the world. Balance between colonization and immunity seems to be essential in disease control. Reduction in antimicrobial use in veterinary medicine requires the implementation of preventive measures, based on alternative tools such as vaccination and other strategies to guarantee a beneficial microbial colonization of the animals. The present review summarizes and discusses the current knowledge on diagnosis and control of Glässer's disease, including prospects on alternatives to antimicrobials.
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Affiliation(s)
- Mar Costa-Hurtado
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain.
| | | | | | - Virginia Aragon
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain; OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain.
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Wen W, Shi L, Chen X. Simultaneous Detection of Actinobacillus pleuropneumoniae and Haemophilus parasuis in Pig by Duplex Droplet Digital PCR. EFOOD 2020. [DOI: 10.2991/efood.k.200918.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Lange MD, Abernathy J, Farmer BD. Evaluation of a Recombinant Flavobacterium columnare DnaK Protein Vaccine as a Means of Protection Against Columnaris Disease in Channel Catfish ( Ictalurus punctatus). Front Immunol 2019; 10:1175. [PMID: 31244827 PMCID: PMC6562308 DOI: 10.3389/fimmu.2019.01175] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/08/2019] [Indexed: 01/18/2023] Open
Abstract
Flavobacterium columnare causes substantial losses among cultured finfish species. The Gram-negative bacterium is an opportunistic pathogen that manifests as biofilms on the host's mucosal surfaces as the disease progresses. We previously demonstrated that the dominant mucosal IgM antibody response to F. columnare is to the chaperone protein DnaK that is found in the extracellular fraction. To establish the efficacy of using recombinant protein technology to develop a new vaccine against columnaris disease, we are reporting on two consecutive years of vaccine trials using a recombinant F. columnare DnaK protein (rDnaK). In year one, three groups of channel catfish (n = 300) were immunized by bath immersion with a live attenuated F. columnare isolate, rDnaK or sham immunized. After 6 weeks, an F. columnare laboratory challenge showed a significant increase in survival (>30%) in both the live attenuated and rDnaK vaccines when compared to the non-immunized control. A rDnaK-specific ELISA revealed significant levels of mucosal IgM antibodies in the skin of catfish immunized with rDnaK at 4- and 6-weeks post immunization. In the second year, three groups of channel catfish (n = 300) were bath immunized with rDnaK alone or with rDnaK after a brief osmotic shock or sham immunized. After 6 weeks a laboratory challenge with F. columnare was conducted and showed a significant increase in survival in the rDnaK (> 25%) and in rDnaK with osmotic shock (>35%) groups when compared to the non-immunized control. The rDnaK-specific ELISA demonstrated significant levels of mucosal IgM antibodies in the skin of catfish groups immunized with rDnaK at 4- and 6-weeks post immunization. To further understand the processes which have conferred immune protection in the rDnaK group, we conducted RNA sequencing of skin samples from the non-immunized (n = 6) and rDnaK treated channel catfish at 1-week (n = 6) and 6 weeks (n = 6) post immunization. Significantly altered gene expression was identified and results will be discussed. Work to further enhance the catfish immune response to F. columnare rDnaK is underway as this protein remains a promising candidate for additional optimization and experimental trials in a production setting.
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Affiliation(s)
- Miles D Lange
- Harry K. Dupree Stuttgart National Aquaculture Research Center, Agricultural Research Service, United States Department of Agriculture, Stuttgart, AR, United States
| | - Jason Abernathy
- Harry K. Dupree Stuttgart National Aquaculture Research Center, Agricultural Research Service, United States Department of Agriculture, Stuttgart, AR, United States
| | - Bradley D Farmer
- Harry K. Dupree Stuttgart National Aquaculture Research Center, Agricultural Research Service, United States Department of Agriculture, Stuttgart, AR, United States
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