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Yang H, Zhang M, Wang X, Gong P, Zhang N, Zhang X, Li X, Li J. Cryptosporidium parvum maintains intracellular survival by activating the host cellular EGFR-PI3K/Akt signaling pathway. Mol Immunol 2023; 154:69-79. [PMID: 36621060 DOI: 10.1016/j.molimm.2023.01.002] [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: 11/23/2022] [Revised: 12/29/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
Autophagy is a critical cellular mechanism in helping infected cells remove intracellular pathogens and is countered by pathogens maintaining intracellular survival by regulating autophagy through the manipulation of the host cellular signal transduction pathway. Cryptosporidium parvum is a zoonotic intracellular but extracytoplasmic protozoon that causes diarrhea in infants and young children worldwide. However, it is still unclear how Cryptosporidium adapts to intracellular survival. In the present study, we demonstrated that C. parvum could activate the EGFR-PI3K/Akt signaling pathway to promote intracellular survival in HCT-8 cells. The western blot results showed that C. parvum induced EGFR and Akt phosphorylation in HCT-8 cells. The EGFR inhibitor AG1478 decreased EGFR and Akt phosphorylation, and the PI3K inhibitor LY294002 impaired Akt phosphorylation induced by C. parvum in HCT-8 cells. Inhibition of EGFR or Akt decreased the number of intracellular parasites. Second, low-dose infection of C. parvum triggered complete autophagy and enhanced autophagic flux in HCT-8 cells. The expressions of mTOR and p62 were decreased, and the expressions of LC3 and Beclin1 were increased in C. parvum-infected HCT-8 cells. Transfection with siBeclin1 or siATG7 reduced LC3 accumulation, while lysosome inhibitor E64d+pepA increased LC3 accumulation induced by C. parvum in HCT-8 cells. Intracellular parasite proliferation was decreased when treated with autophagy inducer rapamycin, whereas autophagy inhibitor 3-MA, E64d+pep A, siBeclin1 or siATG7 increased intracellular parasites. Third, C. parvum inhibited autophagy killing to promote its own intracellular survival by activating EGFR-Akt signaling pathway. The EGFR inhibitor AG1478 enhanced autophagic flux, and Akt inhibitor IV increased LC3 accumulation and inhibited C. parvum proliferation in HCT-8 cells. Akt inhibitor IV-inhibited C. parvum proliferation was attenuated by E64d+pepA. In summary, C. parvum could maintain intracellular survival by inhibiting autophagy via EGFR-PI3K/Akt pathway. These results revealed a new mechanism for the interaction of C. parvum with host cells.
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Affiliation(s)
- Heng Yang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Mengge Zhang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Xiaocen Wang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Pengtao Gong
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Nan Zhang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Xichen Zhang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Xin Li
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China.
| | - Jianhua Li
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun 130062, China.
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Global phosphoproteome analysis reveals significant differences between sporulated oocysts of virulent and avirulent strains of Toxoplasma gondii. Microb Pathog 2021; 161:105240. [PMID: 34655729 DOI: 10.1016/j.micpath.2021.105240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/15/2021] [Accepted: 10/06/2021] [Indexed: 11/23/2022]
Abstract
In this study, the differences in the phosphoproteomic landscape of sporulated oocysts between virulent and avirulent strains of Toxoplasma gondii were examined using a global phosphoproteomics approach. Phosphopeptides from sporulated oocysts of the virulent PYS strain (Chinese ToxoDB#9) and the avirulent PRU strain (type II) were enriched by titanium dioxide (TiO2) affinity chromatography and quantified using IBT approach. A total of 10,645 unique phosphopeptides, 8181 nonredundant phosphorylation sites and 2792 phosphoproteins were identified. We also detected 4129 differentially expressed phosphopeptides (DEPs) between sporulated oocysts of PYS strain and PRU strain (|log1.5 fold change| > 1 and p < 0.05), including 2485 upregulated and 1644 downregulated phosphopeptides. Motif analysis identified 24 motifs from the upregulated phosphorylated peptides including 22 serine motifs and two threonine motifs (TPE and TP), and 15 motifs from the downregulated phosphorylated peptides including 12 serine motifs and three threonine motifs (TP, RxxT and KxxT) in PYS strain when comparing PYS strain to PRU strain. Several kinases were consistent with motifs of overrepresented phosphopeptides, such as PKA, PKG, CKII, IKK, MAPK, EGFR, INSR, Jak, Syk, Src, Ab1. GO enrichment, KEGG pathway analysis and STRING analysis revealed DEPs significantly enriched in many biological processes and pathways. Kinase related network analysis showed that AGC kinase was the most connected kinase peptide. Our findings reveal significant difference in phosphopeptide profiles of sporulated oocysts between virulent and avirulent T. gondii strains, providing new resources for further elucidation of the mechanisms underpinning the virulence of T. gondii.
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Braz CU, Rowan TN, Schnabel RD, Decker JE. Genome-wide association analyses identify genotype-by-environment interactions of growth traits in Simmental cattle. Sci Rep 2021; 11:13335. [PMID: 34172761 PMCID: PMC8233360 DOI: 10.1038/s41598-021-92455-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 06/07/2021] [Indexed: 02/06/2023] Open
Abstract
Understanding genotype-by-environment interactions (G × E) is crucial to understand environmental adaptation in mammals and improve the sustainability of agricultural production. Here, we present an extensive study investigating the interaction of genome-wide SNP markers with a vast assortment of environmental variables and searching for SNPs controlling phenotypic variance (vQTL) using a large beef cattle dataset. We showed that G × E contribute 10.1%, 3.8%, and 2.8% of the phenotypic variance of birth weight, weaning weight, and yearling weight, respectively. G × E genome-wide association analysis (GWAA) detected a large number of G × E loci affecting growth traits, which the traditional GWAA did not detect, showing that functional loci may have non-additive genetic effects regardless of differences in genotypic means. Further, variance-heterogeneity GWAA detected loci enriched with G × E effects without requiring prior knowledge of the interacting environmental factors. Functional annotation and pathway analysis of G × E genes revealed biological mechanisms by which cattle respond to changes in their environment, such as neurotransmitter activity, hypoxia-induced processes, keratinization, hormone, thermogenic and immune pathways. We unraveled the relevance and complexity of the genetic basis of G × E underlying growth traits, providing new insights into how different environmental conditions interact with specific genes influencing adaptation and productivity in beef cattle and potentially across mammals.
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Affiliation(s)
- Camila U Braz
- Division of Animal Sciences, University of Missouri, Columbia, MO, 65211, USA
| | - Troy N Rowan
- Division of Animal Sciences, University of Missouri, Columbia, MO, 65211, USA
- Genetics Area Program, University of Missouri, Columbia, MO, 65211, USA
| | - Robert D Schnabel
- Division of Animal Sciences, University of Missouri, Columbia, MO, 65211, USA
- Genetics Area Program, University of Missouri, Columbia, MO, 65211, USA
- Informatics Institute, University of Missouri, Columbia, MO, 65211, USA
| | - Jared E Decker
- Division of Animal Sciences, University of Missouri, Columbia, MO, 65211, USA.
- Genetics Area Program, University of Missouri, Columbia, MO, 65211, USA.
- Informatics Institute, University of Missouri, Columbia, MO, 65211, USA.
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Wang P, Jia Y, Han Y, Wang W, Zhu Y, Xu J, Guan C, Ying J, Deng S, Wang J, Zhang X, Chen M, Cheng C, Song H. Eimeria acervulina Microneme Protein 3 Inhibits Apoptosis of the Chicken Duodenal Epithelial Cell by Targeting the Casitas B-Lineage Lymphoma Protein. Front Vet Sci 2021; 8:636809. [PMID: 34141730 PMCID: PMC8204691 DOI: 10.3389/fvets.2021.636809] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Eimeria acervulina (E. acervulina) causes coccidiosis in poultry which persists as economic pain worldwide. Most damage to the intestinal mucosa results from apoptosis of the infected intestinal epithelial cells. The Microneme protein 3 (MIC3) protein is a key virulence factor in some parasites involved in host cell apoptosis inhibition. Here, we studied whether and how MIC3 affects the apoptosis in E. acervulina infected chicken duodenal epithelial cells. Through flow cytometry (FCM), we found that the presence of merozoites and the overexpression of MIC3 significantly decreased apoptosis and the activity of caspase-3 in chicken duodenal epithelial cells at 4, 6, and 8 h post merozoite infection (P < 0.01). Silencing the Casitas B-lineage lymphoma (CBL) protein, a host receptor for MIC3 with shRNA was shown to promote apoptosis in the chicken duodenal epithelial cells. The early apoptotic rate of host cells in the lentiviral-MIC3 group was significantly lower than that in the lentiviral-MIC3 + shRNA CBL group at 4 h after MIC3 expression (P < 0.01), and it was moderately decreased in the lentiviral-MIC3 + shRNA CBL group compared with that in the shRNA CBL group. Our data indicated that MIC3 inhibited early apoptosis of E. acervulina infected chicken duodenal epithelial cells by targeting host receptor-CBL protein. These findings unveiled one of the mechanisms of how intracellular parasites affect the apoptosis of infected host cells, which provided a deeper understanding of their pathogenesis.
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Affiliation(s)
- Pu Wang
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Yukun Jia
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Yue Han
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Weirong Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yiran Zhu
- Jixian Honors College, Zhejiang A&F University, Hangzhou, China
| | - Jiali Xu
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Chiyu Guan
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Jinpeng Ying
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Simin Deng
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Jing Wang
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Xian Zhang
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Mianmian Chen
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Changyong Cheng
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
| | - Houhui Song
- Key Laboratory of Applied Technology on Green-Eco Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China
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Li L, Wang XC, Gong PT, Zhang N, Zhang X, Li S, Li X, Liu SX, Zhang XX, Li W, Li JH, Zhang XC. ROS-mediated NLRP3 inflammasome activation participates in the response against Neospora caninum infection. Parasit Vectors 2020; 13:449. [PMID: 32891167 PMCID: PMC7487665 DOI: 10.1186/s13071-020-04331-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 08/30/2020] [Indexed: 12/14/2022] Open
Abstract
Background Neospora caninum is an obligate intracellular protozoan that causes neosporosis, N. caninum infection is a major cause of abortion in cattle worldwide. Currently, specific treatment for neosporosis is not available. The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a cytoplasmic protein complex that plays an important role in host defense against N. caninum infection, but the underlying mechanisms are poorly understood. Methods The reactive oxygen species (ROS) inhibitor and the ROS inducer, wild-type (WT) and NLRP3-deficient peritoneal macrophages or mice were used to investigate the role of ROS in NLRP3 inflammasome activation and controlling parasite burdens. ROS production, cell death and cell viability, production of inflammasome-mediated IL-1β or IL-18, cleavage of caspase-1 and NLRP3 expression, as well as parasite burdens were detected. Results In vitro, N. caninum induced ROS generation in a dose-dependent manner in peritoneal macrophages. The pretreatment of ROS inhibitor N-acetyl-l-cysteine (NAC) significantly attenuated N. caninum-induced ROS production, LDH release, IL-1β secretion and NLRP3 expression, whereas N. caninum proliferation was notably increased. In contrary, the ROS inducer pyrogallol (PG) significantly enhanced ROS production and NLRP3 inflammasome activity and decreased the parasite burden in N. caninum-infected peritoneal macrophages. NADPH-dependent ROS-mediated NLRP3 inflammasome activation induced by N. caninum can also be confirmed by using the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI). However, the NAC or DPI pre-treatment or PG treatment did not significantly alter N. caninum-induced inflammasome activities and parasite proliferation in Nlrp3−/− peritoneal macrophages. In vivo, IL-18 releases in serum and parasite burdens in peritoneal exudate cells were significantly increased in PG-treated WT mice after infection with N. caninum; however, IL-18 productions and parasite burdens were not changed in PG-treated Nlrp3−/− mice. Furthermore, PG treatment in WT mice infected with N. caninum significantly decreased the mortality, weight loss and parasite burdens in tissues and histopathological lesions. Conclusions Neospora caninum-induced NADPH-dependent ROS generation plays an important role in NLRP3 inflammasome activation and controlling parasites. The ROS inducer PG can control N. caninum infection mainly by promoting NLRP3 inflammasome activation. ROS-mediated NLRP3 inflammasome axis can be a potential therapeutic target for neosporosis.![]()
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Affiliation(s)
- Lu Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Xiao-Cen Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Peng-Tao Gong
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Nan Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Xu Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Shan Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Xin Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Shao-Xiong Liu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Xiao-Xu Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China
| | - Wei Li
- Heilongjiang Key Laboratory for Zoonosis, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Jian-Hua Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China.
| | - Xi-Chen Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China.
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Miroud K, Benlakehal A, Kaidi R. Seroprevalence of anti- Neospora caninum antibodies in cows of North-Eastern Algeria. Vet World 2019; 12:765-768. [PMID: 31439990 PMCID: PMC6661496 DOI: 10.14202/vetworld.2019.765-768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 04/16/2019] [Indexed: 11/22/2022] Open
Abstract
AIM The present cross-sectional study aimed at assessing the seroprevalence of Neospora caninum infection both at herd and within herd and at determining risk factors that are associated with its seropositivity. MATERIALS AND METHODS A total of 90 cows distributed over seven herds located in two North-Eastern Algerian provinces were blood sampled in order to be tested for the presence of antibodies against N. caninum using a commercially available enzyme-linked immunosorbent assay kit. RESULTS The individual seroprevalence of N. caninum was found to be 12.22%, and six of the seven herds tested had at least one seropositive cow. The logistic regression model revealed that abortion (odds ratio [OR]=29.15) and parity (OR=7.38) were positively associated with the seropositivity of animals on an individual basis. CONCLUSION The study confirms the existence of N. caninum infection in cattle in North-Eastern Algeria. However, a widespread infection rate of 85.71% and its significant statistical association with previous abortion (OR=29.15) need further investigations.
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Affiliation(s)
- Kamel Miroud
- Research Laboratory of Epidemio-Surveillance, Production and Reproduction, Health, Cellular Experimentation and Therapy of Domestic and Wild Animals, Department of Veterinary Sciences, University Chadli Bendjedid, BP 73, El-Tarf 36000, Algeria
| | - Amar Benlakehal
- Department of Applied Biology, Institute of Biology, University Larbi Tebessi, Route de Constantine, Tebessa 12000, Algeria
| | - Rachid Kaidi
- Veterinary Institute, University Saad Dahleb, Route de Soumaa, BP 270, Blida 9000, Algeria
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Li S, Gong P, Zhang N, Li X, Tai L, Wang X, Yang Z, Yang J, Zhu X, Zhang X, Li J. 14-3-3 Protein of Neospora caninum Modulates Host Cell Innate Immunity Through the Activation of MAPK and NF-κB Pathways. Front Microbiol 2019; 10:37. [PMID: 30740096 PMCID: PMC6355710 DOI: 10.3389/fmicb.2019.00037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 01/10/2019] [Indexed: 12/30/2022] Open
Abstract
Neospora caninum is an obligate intracellular apicomplexan parasite, the etiologic agent of neosporosis, and a major cause of reproductive loss in cattle. There is still a lack of effective prevention and treatment measures. The 14-3-3 protein is a widely expressed acidic protein that spontaneously forms dimers within apicomplexan parasites. This protein has been isolated and sequenced in many parasites; however, there are few reports about the N. caninum 14-3-3 protein. Here, we successfully expressed and purified a recombinant fusion protein of Nc14-3-3 (rNc14-3-3) and prepared a polyclonal antibody. Immunofluorescence and immunogold electron microscopy studies of tachyzoites or N. caninum-infected cells suggested that 14-3-3 was localized in the cytosol and the membrane. Western blotting analysis indicated that rNc14-3-3 could be recognized by N. caninum-infected mouse sera, suggesting that 14-3-3 may be an infection-associated antigen that is involved in the host immune response. We demonstrated that rNc14-3-3 induced cytokine expression by activating the MAPK and AKT signaling pathways, and inhibitors of p38, ERK, JNK, and AKT could significantly decrease the production of IL-6, IL-12p40, and TNF-α. In addition, phosphorylated nuclear factor-κB (NF-κB/p65) was observed in wild-type peritoneal macrophages (PMs) treated with rNc14-3-3, and the protein level of NF-κB/p65 was reduced in the cytoplasm but increased correspondingly in the nucleus after 2 h of treatment. These results were also observed in deficient in TLR2-/- PMs. Taken together, our results indicated that the N. caninum 14-3-3 protein can induce effective immune responses and stimulate cytokine expression by activating the MAPK, AKT, and NF-κB signaling pathways but did not dependent TLR2, suggesting that Nc14-3-3 is a novel vaccine candidate against neosporosis.
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Affiliation(s)
- Shan Li
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Pengtao Gong
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Nan Zhang
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xin Li
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Lixin Tai
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xu Wang
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zhengtao Yang
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ju Yang
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xingquan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xichen Zhang
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianhua Li
- Key Laboratory of Zoonosis Research by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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