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Wan W, Li Y, Wang J, Jin Z, Xin W, Kang L, Wang J, Li X, Cao Y, Yang H, Wang J, Gao S. PLGA Nanoparticle-Based Dissolving Microneedle Vaccine of Clostridium perfringens ε Toxin. Toxins (Basel) 2023; 15:461. [PMID: 37505730 PMCID: PMC10467084 DOI: 10.3390/toxins15070461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/12/2023] [Accepted: 07/14/2023] [Indexed: 07/29/2023] Open
Abstract
Epsilon toxin (ETX) is an exotoxin produced by type B and D Clostridium perfringens that causes enterotoxemia or necrotic enteritis in animals such as goats, sheep, and cattle. Vaccination is a key method in preventing such diseases. In this study, we developed a new type of dissolving microneedle patch (dMN) with a nanoparticle adjuvant for enhanced immune response to deliver the rETXY196E-C protein vaccine. We chose FDA-approved poly(lactic-co-glycolic acid) (PLGA) to prepare nanospheres as the vaccine adjuvant and introduced dimethyldioctadecylammonium bromide (DDAB) to make the surface of PLGA nanoparticles (PLGA NPs) positively charged for antigen adsorption. PLGA NPs with a diameter of 100~200 nm, a surface ZETA potential of approximately +40 mV, and good safety were successfully prepared and could effectively adsorb rETXY196E-C protein. Using non-toxic and antibacterial fish gelatin as the microneedle (MN) matrix, we prepared a PLGA-DDAB dMN vaccine with good mechanical properties that successfully penetrated the skin. After immunization of subcutaneous (SC) and dMN, antibody titers of the PLGA and Al adjuvant groups were similar in both two immune ways. However, in vivo neutralization experiments showed that the dMN vaccines had a better protective effect. When challenged with 100 × LD50 GST-ETX, the survival rate of the MN group was 100%, while that of the SC Al group was 80%. However, a 100% protective effect was achieved in both immunization methods using PLGA NPs. In vitro neutralization experiments showed that the serum antibodies from the dMN and SC PLGA NPs groups both protect naive mice from 10 × LD50 GST-ETX attack after being diluted 20 times and could also protect MDCK cells from 20 × CT50 GST-ETX attack. In conclusion, the PLGA-DDAB dMN vaccine we prepared has good mechanical properties, immunogenicity, and protection, and can effectively prevent ETX poisoning. This provides a better way of delivering protein vaccines.
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Affiliation(s)
- Wei Wan
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yue Li
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
| | - Jing Wang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
| | - Zhiying Jin
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang 050024, China
| | - Wenwen Xin
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
| | - Lin Kang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
| | - Junhong Wang
- School of Medical Technology, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China;
| | - Xiaoyang Li
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yakun Cao
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang 050024, China
| | - Hao Yang
- Beijing Noninvasion Biomedical Technology Co., Ltd., Beijing 101111, China;
| | - Jinglin Wang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
| | - Shan Gao
- State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China; (W.W.); (Y.L.); (J.W.); (Z.J.); (W.X.); (L.K.); (X.L.); (Y.C.)
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Huang J, Zhao B, Liu T, Kang L, Li J, Guo Z, Chen M, Gao S, Wang J, Li Y, Wang J, Xin W. Statins as Potential Preventative Treatment of ETX and Multiple Pore-Forming Toxin-Induced Diseases. Int J Mol Sci 2023; 24:ijms24065414. [PMID: 36982489 PMCID: PMC10048941 DOI: 10.3390/ijms24065414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023] Open
Abstract
Epsilon toxin (ETX), produced by type B and D strains of Clostridium perfringens, can cause fatal enterotoxaemia in ruminant animals, particularly sheep, cattle, and goats. Previous studies show that the cytotoxicity of ETX is dependent on the integrity of lipid rafts, the maintenance of which is ensured by cholesterol. Zaragozic acid (ZA) is a statin drug that reduces the synthesis of squalene, which is responsible for cholesterol synthesis. In this study, ZA significantly reduced the toxicity of ETX in Madin–Darby canine kidney (MDCK) cells. We show that ZA does not affect the binding of ETX to MDCK cells, but propidium iodide staining (PI) and Western blotting confirmed that ZA significantly disrupts the ability of ETX to form pores or oligomers in MDCK cells. Additionally, ZA decreased the phosphatidylserine exposure on the plasma membrane and increased the Ca2+ influx of the cells. Results of density gradient centrifugation suggest that ZA decreased the number of lipid rafts in MDCK membranes, which probably contributed to the attenuation of pore-formation. Moreover, ZA protected mice against ETX in vivo. All mice pre-treated with ZA for 48 h before exposure to an absolute lethal dose of ETX (6400 ng/kg) survived. In summary, these findings provide an innovative method to prevent ETX intoxication. Considering many pore-forming toxins require lipid rafts, we tested and found ZA also inhibited the toxicity of other toxins such as Clostridium perfringens Net B and β-toxin (CPB) and Staphylococcus aureus α-hemolysin (Hla). We expect ZA can thus be developed as a broad-spectrum medicine for the treatment of multiple toxins. In addition, other statins, such as lovastatin (LO), also reduced the toxicity of ETX. These findings indicate that statin medicines are potential candidates for preventing and treating multiple toxin-induced diseases.
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Affiliation(s)
- Jing Huang
- Life Science Institute, Hebei Normal University, Shijiazhuang 050024, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Baohua Zhao
- Life Science Institute, Hebei Normal University, Shijiazhuang 050024, China
| | - Tingting Liu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Lin Kang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Jiaxin Li
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Zishuo Guo
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Ming Chen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Shan Gao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Jing Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Yanwei Li
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
| | - Jinglin Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
- Correspondence: (J.W.); (W.X.)
| | - Wenwen Xin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences (AMMS), Beijing 100071, China
- Correspondence: (J.W.); (W.X.)
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A non-toxic recombinant bivalent chimeric protein rETX m3CSA m4/TMD as a potential vaccine candidate against enterotoxemia and braxy. Vaccine 2023; 41:1232-1238. [PMID: 36635138 DOI: 10.1016/j.vaccine.2022.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 11/11/2022] [Accepted: 11/13/2022] [Indexed: 01/11/2023]
Abstract
Clostridium perfringens epsilon toxin (ETX) and Clostridium septicum alpha toxin (CSA) are lethal and necrotizing toxins, which play key roles in enterotoxemia and braxy of ruminants, respectively. In the present study, we synthesized a bivalent chimeric protein rETXm3CSAm4/TMD comprising ETXm3 (Y30A/H106P/Y196A) and CSAm4/TMD (C86L/N296A/H301A/W342A and a deletion of residues 212 to 222). Compared with recombinant ETX and recombinant CSA, rETXm3CSAm4/TMD showed no cytotoxicity in Madin-Darby Canine Kidney cells and was not fatal to mice. Moreover, rETXm3CSAm4/TMD could protect immunized mice against 10 × mouse LD100 of crude ETX or 3 × mouse LD100 of crude CSA without obvious histopathologic difference. Most importantly, both rabbits and sheep immunized with rETXm3CSAm4/TMD produced high titers of neutralizing antibody which protected the animals against the challenge with crude ETX or crude CSA. These data suggest that genetically detoxified rETXm3CSAm4/TMD is a potential subunit vaccine candidate against enterotoxemia and braxy.
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Etx-Y71A as a non-toxic mutant of Clostridium perfringens epsilon toxin induces protective immunity in mice and sheep. Vaccine 2020; 38:6553-6561. [PMID: 32788135 DOI: 10.1016/j.vaccine.2020.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/25/2020] [Accepted: 08/03/2020] [Indexed: 11/21/2022]
Abstract
Epsilon toxin (Etx) is an extremely potent toxin produced by Clostridium perfringens toxinotypes B and D, which cause fatal enterotoxemia in many livestock species, mainly sheep and goats. Our previous study demonstrated that the aromatic amino acid (AA) residue at position 71 in domain III of Etx is needed for its cytotoxic activity toward MDCK cells. Here, we first determined that Etx mutants with non-aromatic AA substitutions at Tyr71 lost lethality in mice, indicating that the aromatic AA residue at position 71 is a toxicity determinant of Etx in vivo. After intravenous injection with a high dose of the trypsin-activated Etx-Y71A mutant, mice did not show any histopathological lesions, and confocal microscopy observations further showed that Etx-Y71A lost the ability to cross the blood-brain barrier of the mice. These results suggested that the Etx-Y71A mutant is sufficiently safe in vivo to be a vaccine candidate. Furthermore, the immune efficacy of Etx-Y71A was evaluated in model and host animals. Mice inoculated with this mutant produced high levels of neutralizing antibodies and were completely protected from a 100 LD50 of trypsin-activated Etx challenge. Sheep immunized with Etx-Y71A produced high levels of neutralizing antibodies that provided protection in mice against an activated Etx challenge, and lambs could receive passive immunity through immunization of pregnant ewes. Additionally, homology modeling and circular dichroism analysis showed that Etx-Y71A has structural similarity to Etx, which provides a structural basis for Etx-Y71A retaining the immunogenicity of Etx. Taken together, these results suggest that Etx-Y71A is a potential vaccine candidate against Etx-inducing enterotoxemia.
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A Novel Panel of Rabbit Monoclonal Antibodies and Their Diverse Applications Including Inhibition of Clostridium perfringens Epsilon Toxin Oligomerization. Antibodies (Basel) 2018; 7:antib7040037. [PMID: 31544887 PMCID: PMC6698963 DOI: 10.3390/antib7040037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/18/2018] [Accepted: 10/22/2018] [Indexed: 12/18/2022] Open
Abstract
The pore-forming epsilon toxin (ETX) produced by Clostridium perfringens is among the most lethal bacterial toxins known. Sensitive antibody-based reagents are needed to detect toxin, distinguish mechanisms of cell death, and prevent ETX toxicity. Using B-cell immuno-panning and cloning techniques, seven ETX-specific monoclonal antibodies were generated from immunized rabbits. ETX specificity and sensitivity were evaluated via western blot, ELISA, immunocytochemistry (ICC), and flow cytometry. ETX-neutralizing function was evaluated both in vitro and in vivo. All antibodies recognized both purified ETX and epsilon protoxin via western blot with two capable of detecting the ETX-oligomer complex. Four antibodies detected ETX via ELISA and three detected ETX bound to cells via ICC or flow cytometry. Several antibodies prevented ETX-induced cell death by either preventing ETX binding or by blocking ETX oligomerization. Antibodies that blocked ETX oligomerization inhibited ETX endocytosis and cellular vacuolation. Importantly, one of the oligomerization-blocking antibodies was able to protect against ETX-induced death post-ETX exposure in vitro and in vivo. Here we describe the production of a panel of rabbit monoclonal anti-ETX antibodies and their use in various biological assays. Antibodies possessing differential specificity to ETX in particular conformations will aid in the mechanistic studies of ETX cytotoxicity, while those with ETX-neutralizing function may be useful in preventing ETX-mediated mortality.
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Kang J, Gao J, Yao W, Kang L, Gao S, Yang H, Ji B, Li P, Liu J, Yao J, Xin W, Zhao B, Wang J. F199E substitution reduced toxicity of Clostridium perfringens epsilon toxin by depriving the receptor binding capability. Hum Vaccin Immunother 2017; 13:1598-1608. [PMID: 28304231 DOI: 10.1080/21645515.2017.1303022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epsilon toxin (ETX), a potent toxin, is produced by types B and D strains of Clostridium perfringens, which could cause severe diseases in humans and domestic animals. Mutant rETXF199E was previously demonstrated to be a good vaccine candidate. However, the mechanism concerned remains unknown. To clarify how F199E substitution reduced ETX toxicity, we performed a series of experiments. The results showed that the cell-binding and pore-forming ability of rETXF199E was almost abolished. We speculated that F199E substitution reduced toxicity by depriving the receptor binding capability of ETX, which contributed to the hypothesis that domain I of ETX is responsible for cell binding. In addition, our data suggested that ETX could cause Ca2+ release from intracellular Ca2+ stores, which may underlie an alternate pathway leading to cell death. Furthermore, ETX induced crenation of the MDCK cells was observed, with sags and crests first appearing on the surface of condensed MDCK cells, according to scanning electron microscopy. The data also demonstrated the safety and potentiality of rETXF199E as a vaccine candidate for humans. In summary, findings of this work potentially contribute to a better understanding of the pathogenic mechanism of ETX and the development of vaccine against diseases caused by ETX, using mutant proteins.
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Affiliation(s)
- Jingjing Kang
- a Life Science Institute of Hebei Normal University , Shijiazhuang, Hebei Province , PR China
| | - Jie Gao
- a Life Science Institute of Hebei Normal University , Shijiazhuang, Hebei Province , PR China
| | - Wenwu Yao
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Lin Kang
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Shan Gao
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Hao Yang
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Bin Ji
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Ping Li
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Jing Liu
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Jiahao Yao
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Wenwen Xin
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
| | - Baohua Zhao
- a Life Science Institute of Hebei Normal University , Shijiazhuang, Hebei Province , PR China
| | - Jinglin Wang
- b State Key Laboratory of Pathogen and Biosecurity , Institute of Microbiology and Epidemiology , Beijing , PR China
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Structural pierce into molecular mechanism underlying Clostridium perfringens Epsilon toxin function. Toxicon 2017; 127:90-99. [PMID: 28089770 DOI: 10.1016/j.toxicon.2017.01.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 01/09/2017] [Accepted: 01/10/2017] [Indexed: 12/17/2022]
Abstract
Epsilon toxin of the Clostridium perfringens garnered a lot of attention due to its potential for toxicity in humans, extreme potency for cytotoxicity in mice and lack of any approved therapeutics prescribed for human. However, the intricacies of the Epsilon toxin action mechanism are yet to be understood. In this regard, various in silico tools have been exploited to model and refine the 3D structure of the toxin and its two receptors. The receptor proteins were embedded into designed lipid membranes within an aqueous and ionized environment. Thereafter, the modeled structures subjected to series of consecutive molecular dynamics runs to achieve the most natural like coordination for each model. Ultimately, protein-protein interaction analyses were performed to understand the probable action mechanism. The obtained results successfully confirmed the accuracy of employed methods to achieve high quality models for the toxin and its receptors within their lipid bilayers. Molecular dynamics analyses lead the structures to a more native like coordination. Moreover, the results of previous empirical studies were confirmed, while new insights for action mechanisms including the detailed roles of Hepatitis A virus cellular receptor 1 (HAVCR1) and Myelin and lymphocyte protein (MAL) proteins were achieved. In light of previous and our observations, we suggested novel models which elucidated the existing interplay between potential players of Epsilon toxin action mechanism with detailed structural evidences. These models would pave the way to have more robust understanding of the Epsilon toxin biology, more precise vaccine construction and more successful drug (inhibitor) design.
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Immunization with a novel Clostridium perfringens epsilon toxin mutant rETX(Y196E)-C confers strong protection in mice. Sci Rep 2016; 6:24162. [PMID: 27048879 PMCID: PMC4822168 DOI: 10.1038/srep24162] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/21/2016] [Indexed: 11/08/2022] Open
Abstract
Epsilon toxin (ETX) is produced by toxinotypes B and D of Clostridium perfringens. It can induce lethal enterotoxemia in domestic animals, mainly in sheep, goats and cattle, causing serious economic losses to global animal husbandry. In this study, a novel and stable epsilon toxin mutant rETXY196E-C, obtained by substituting the 196th tyrosine (Y196) with glutamic acid (E) and introducing of 23 amino acids long C-terminal peptide, was determined as a promising recombinant vaccine candidate against enterotoxemia. After the third vaccination, the antibody titers against recombinant wild type (rETX) could reach 1:105 in each immunized group, and the mice were completely protected from 100 × LD50 (50% lethal dose) of rETX challenge. The mice in 15 μg subcutaneously immunized group fully survived at the dose of 500 × LD50 of rETX challenge and 80% of mice survived at 180 μg (1000 × LD50) of rETX administration. In vitro, immune sera from 15 μg subcutaneously immunized group could completely protect MDCK cells from 16 × CT50 (50% lethal dose of cells) of rETX challenge and protect against 10 × LD50 dose (1.8 μg) of rETX challenge in mice. These data suggest that recombinant protein rETXY196E-C is a potential vaccine candidate for future applied researches.
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