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Cell Lines for the Development of African Swine Fever Virus Vaccine Candidates: An Update. Vaccines (Basel) 2022; 10:vaccines10050707. [PMID: 35632463 PMCID: PMC9144233 DOI: 10.3390/vaccines10050707] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/27/2022] [Accepted: 04/27/2022] [Indexed: 01/27/2023] Open
Abstract
African swine fever virus (ASFV) is the etiological agent of a highly lethal disease in both domestic and wild pigs. The virus has rapidly spread worldwide and has no available licensed vaccine. An obstacle to the construction of a safe and efficient vaccine is the lack of a suitable cell line for ASFV isolation and propagation. Macrophages are the main targets for ASFV, and they have been widely used to study virus–host interactions; nevertheless, obtaining these cells is time-consuming and expensive, and they are not ethically suitable for the production of large-scale vaccines. To overcome these issues, different virulent field isolates have been adapted on monkey or human continuous cells lines; however, several culture passages often lead to significant genetic modifications and the loss of immunogenicity of the adapted strain. Thus, several groups have attempted to establish a porcine cell line able to sustain ASFV growth. Preliminary data suggested that some porcine continuous cell lines might be an alternative to primary macrophages for ASFV research and for large-scale vaccine production, although further studies are still needed. In this review, we summarize the research to investigate the most suitable cell line for ASFV isolation and propagation.
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Rossi PS, Mattei RI, Schllemer NR, Thomaz GR, Antunes AV, Virmond MP, Taube MJ, Bertagnon HG. The effect of bovine vaccines against respiratory viruses administered either intranasal or intramuscular on broncho-alveolar fluid cells of heifers. Vet Q 2021; 41:97-106. [PMID: 33375918 PMCID: PMC7833023 DOI: 10.1080/01652176.2020.1870019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background The knowledge on bovine vaccines against respiratory viruses on bronchoalveolar fluid cells is scarce. Objective To compare the effects of a commercial intranasal (IN) and intramuscular (IM) vaccine against bovine respiratory disease (BRD) complex viruses on bronchoalveolar fluid cells of healthy heifers. Methods 21 healthy heifers were assigned to three treatment groups: control (CO, N = 7), intranasally vaccinated (IN) (n = 7), and intramuscularly vaccinated (IM) (n = 7). The IN group received 1 mL of the commercial vaccine in each nostril once containing attenuated BoHV-1, bPIV-3, and BRSV. The IM group was vaccinated with two doses of 2 mL with an interval of 21 days of the commercial vaccine containing attenuated BoHV-1, bPIV-3, and BRSV plus inactivated BVDV. At day 0 (D0), before the first vaccine dose, and at D3, D7, and D21, after the last vaccine dose, airway bronchoscopy was performed to observe local irritation and collect bronchoalveolar lavage fluid (BALF). The bronchoalveolar count, cytological evaluation, bronchoalveolar cell oxidative metabolism, and total bronchoalveolar IgA and IgG were measured. Results The IN vaccine increased neutrophil cellularity at D7 and D21 and total IgA at D3 in BALF. Total IgA in BALF also increased at D3 and oxidative metabolism of bronchoalveolar cells at D21 lowered compared to the CO group. Following IM vaccination there was no alteration of immunoglobulins or cell oxidative metabolism in BALF. Both vaccines reduced the number of alveolar macrophages. Conclusion Both vaccines induced bronchoalveolar inflammation during the establishment of the vaccine immunity, which was more expressive in the IN protocol.
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Affiliation(s)
- Patricia S Rossi
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Rafael I Mattei
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Natali R Schllemer
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Gabriela R Thomaz
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Anna V Antunes
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Mauricio P Virmond
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Mari J Taube
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
| | - Heloisa G Bertagnon
- Departamento de Medicina Veterinária, Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR, Brazil
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Oh T, Do DT, Vo HV, Kwon HI, Lee SC, Kim MH, Nguyen DTT, Le QTV, Tran TM, Nguyen TT, Lee JY, Chae C. The Isolation and Replication of African Swine Fever Virus in Primary Renal-Derived Swine Macrophages. Front Vet Sci 2021; 8:645456. [PMID: 33816588 PMCID: PMC8017199 DOI: 10.3389/fvets.2021.645456] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/26/2021] [Indexed: 02/04/2023] Open
Abstract
African swine fever virus (ASFV) causes hemorrhagic disease in domestic pigs by replicating mainly in monocyte/macrophage lineages. Various primary cells including pulmonary alveolar macrophages have been used for the propagation of ASFV on this account. However, ethical constraints and consistency problems exist as it is necessary to harvest same phenotype of primary cells in order to continue a study. We suggested renal-derived swine macrophages as a novel primary cell candidate to address these issues. These primary cells proved to be permissive to both cell adapted ASFV and a wild-type ASFV. Compared to the commercial cell line MA-104, the renal-derived macrophages were more suitable to isolate the field virus. The consistent molecular characteristics of the renal-derived macrophages were demonstrated by immunocytochemistry with antibodies against macrophage cell surface markers including CD163, CD172a, and Iba-1. Viral protein p30 and p72 expression in ASFV infected macrophages was confirmed by immunocytochemistry by use of specific monoclonal antibodies. We observed increase of cell-free viral DNA and infectious virus titer in infected cell supernatant in successive days-post-infection. These results demonstrated that primary renal-derived swine macrophages are useful for ASFV isolation and propagation in terms of cell phenotypes, susceptibility to the virus, and virus production.
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Affiliation(s)
- Taehwan Oh
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, Seoul, South Korea
| | - Duy Tien Do
- Faculty of Animal Sciences and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - Hung Van Vo
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Hyeok-Il Kwon
- ChoongAng Vaccine Laboratories, Daejeon, South Korea
| | | | - Min Ho Kim
- ChoongAng Vaccine Laboratories, Daejeon, South Korea
| | - Dung Thi Thu Nguyen
- Faculty of Animal Sciences and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - Quang Tin Vinh Le
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Tan Minh Tran
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Toan Tat Nguyen
- Faculty of Animal Sciences and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam
| | - Joo Young Lee
- ChoongAng Vaccine Laboratories, Daejeon, South Korea
| | - Chanhee Chae
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, Seoul, South Korea
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Sánchez-Carvajal JM, Ruedas-Torres I, Carrasco L, Pallarés FJ, Mateu E, Rodríguez-Gómez IM, Gómez-Laguna J. Activation of regulated cell death in the lung of piglets infected with virulent PRRSV-1 Lena strain occurs earlier and mediated by cleaved Caspase-8. Vet Res 2021; 52:12. [PMID: 33482914 PMCID: PMC7821682 DOI: 10.1186/s13567-020-00882-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/16/2020] [Indexed: 02/06/2023] Open
Abstract
PRRSV-1 virulent strains cause high fever, marked respiratory disease and severe lesions in lung and lymphoid organs. Regulated cell death (RCD), such as apoptosis, necroptosis and pyroptosis, is triggered by the host to interrupt viral replication eliminating infected cells, however, although it seems to play a central role in the immunopathogenesis of PRRSV, there are significant gaps regarding their sequence and activation upon PRRSV-infection. The present study evaluated RCD events by means of caspases expression in the lung of PRRSV-1-infected pigs and their impact on pulmonary macrophage subpopulations and lung lesion. Conventional piglets were intranasally inoculated with the virulent subtype 3 Lena strain or the low virulent subtype 1 3249 strain and euthanised at 1, 3, 6, 8 and 13 dpi. Lena-infected piglets showed severe and early lung damage with a high frequency of PRRSV-N-protein+ cells, depletion of CD163+ cells and high viral load in the lung. The number of TUNEL+ cells was significantly higher than cCasp3+ cells in Lena-infected piglets during the first week post-infection. cCasp8 and to a lesser extent cCasp9 were activated by both PRRSV-1 strains after one week post-infection together with a replenishment of both CD163+ and Arg-1+ pulmonary macrophages. These results highlight the induction of other forms of RCD beyond apoptosis, such as, necroptosis and pyroptosis during the first week post-infection followed by the activation of, mainly, extrinsic apoptosis during the second week post-infection. The recovery of CD163+ macrophages at the end of the study represents an attempt to restore pulmonary macrophage subpopulations lost during the early stages of the infection but also a macrophage polarisation into M2 macrophages.
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Affiliation(s)
- Jose María Sánchez-Carvajal
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain.
| | - Inés Ruedas-Torres
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain.
| | - Librado Carrasco
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain
| | - Francisco José Pallarés
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain
| | - Enric Mateu
- Department of Animal Health and Anatomy, Faculty of Veterinary Medicine, Autonomous University of Barcelona, 08193, Bellaterra, Spain.,Institut de Recerca i Tecnologia Agroalimentàries - Centre de Recerca en Sanitat Animal (IRTA-CReSA), Campus de la Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain
| | - Irene Magdalena Rodríguez-Gómez
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain
| | - Jaime Gómez-Laguna
- Department of Anatomy and Comparative Pathology and Toxicology, Faculty of Veterinary Medicine, University of Córdoba, 14014, Córdoba, Spain
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Qin M, Chen W, Li Z, Wang L, Ma L, Geng J, Zhang Y, Zhao J, Zeng Y. Role of IFNLR1 gene in PRRSV infection of PAM cells. J Vet Sci 2021; 22:e39. [PMID: 34056880 PMCID: PMC8170216 DOI: 10.4142/jvs.2021.22.e39] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/11/2021] [Accepted: 04/15/2021] [Indexed: 01/01/2023] Open
Abstract
Background Interferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear. Objectives The purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV). Methods The effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods. Results In this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV. Conclusion Expression of the IFNLR1 gene has an important regulatory role in PRRSV-infected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV.
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Affiliation(s)
- Ming Qin
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Wei Chen
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Zhixin Li
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Lixue Wang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Lixia Ma
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Jinhong Geng
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Yu Zhang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Jing Zhao
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China
| | - Yongqing Zeng
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Tai' an City, Shandong Province 271018, China.
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Desmonts de Lamache D, Moges R, Siddiq A, Allain T, Feener TD, Muench GP, McKenna N, Yates RM, Buret AG. Immuno-modulating properties of Tulathromycin in porcine monocyte-derived macrophages infected with porcine reproductive and respiratory syndrome virus. PLoS One 2019; 14:e0221560. [PMID: 31442273 PMCID: PMC6707645 DOI: 10.1371/journal.pone.0221560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 08/09/2019] [Indexed: 01/04/2023] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is a positive-stranded RNA virus that grows in macrophages and causes acute pneumonia in pigs. PRRSV causes devastating losses to the porcine industry. However, due to its high antigenic variability and poorly understood immunopathogenesis, there is currently no effective vaccine or treatment to control PRRSV infection. The common occurrence of PRRSV infection with bacterial infections as well as its inflammatory-driven pathobiology raises the question of the value of antibiotics with immunomodulating properties for the treatment of the disease it causes. The macrolide antibiotic Tulathromycin (TUL) has been found to exhibit potent anti-inflammatory and immunomodulating properties in cattle and pigs. The aim of this study was to characterize the anti-viral and immunomodulating properties of TUL in PRRSV-infected porcine macrophages. Our findings indicate that blood monocyte-derived macrophages are readily infected by PRRSV and can be used as an effective cellular model to study PRRSV pathogenesis. TUL did not change intracellular or extracellular viral titers, not did it alter viral receptors (CD163 and CD169) expression on porcine macrophages. In contrast, TUL exhibited potent immunomodulating properties, which therefore occurred in the absence of any direct antiviral effects against PRRSV. TUL had an additive effect with PRRSV on the induction of macrophage apoptosis, and inhibited virus-induced necrosis. TUL significantly attenuated PRRSV-induced macrophage pro-inflammatory signaling (CXCL-8 and mitochondrial ROS production) and prevented PRRSV inhibition of non-opsonized and opsonized phagocytic function. Together, these data demonstrate that TUL inhibits PRRSV-induced inflammatory responses in porcine macrophages and protects against the phagocytic impairment caused by the virus. Research in live pigs is warranted to assess the potential clinical benefits of this antibiotic in the context of virally induced inflammation and tissue injury.
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Affiliation(s)
| | - R. Moges
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - A. Siddiq
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - T. Allain
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - T. D. Feener
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - G. P. Muench
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - N. McKenna
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary AB, Canada
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, AB, Canada
| | - R. M. Yates
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary AB, Canada
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, AB, Canada
| | - A. G. Buret
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
- * E-mail:
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Hostetter SJ, Clark SK, Gilbertie JM, Wiechert SA, Jones DE, Sponseller BA. Age-related variation in the cellular composition of equine bronchoalveolar lavage fluid. Vet Clin Pathol 2017; 46:344-353. [PMID: 28346682 PMCID: PMC10629498 DOI: 10.1111/vcp.12473] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Previous reports reveal variation in the cellular composition of equine bronchoalveolar lavage fluid (BALF). OBJECTIVES The purpose of this study was to compare the profiles of BALF from horses to assess age-related differences. Serial BALF samples were collected from the same individuals over a one-year period to identify changes in individual animals as they aged. METHODS Collection of BALF was performed on horses aged one week and one, 2, 6, and 12 months. Total nucleated cell count (TNCC), protein concentration, and cytology were assessed. Longitudinal analysis was performed and compared to healthy adults. RESULTS Foals at one week and 6 months of age had significantly higher TNCC than adults (medians: 320/μL, 285/μL, and 90/μL, respectively); no differences in total protein were found. Foals at one month had the highest proportion of macrophages (median: 87.3%), differing significantly from both yearlings and adults (medians: 45.5% and 48.7%, respectively). Foals aged one week and one month had significantly lower proportions of lymphocytes than yearlings and adults (medians: 3.2% and 4.7% vs 43.2% and 45.8%, respectively). Eosinophil percentage was lowest in foals aged one week, one month, and 2 months (median: 0.0%) and highest in foals aged 6 months (median: 2.2%). Mast cell percentages were highest in yearlings and adults (medians: 2.2% and 3.3%, respectively) and neutrophil percentage was highest in foals aged one week (13.7%). CONCLUSIONS Cytologic profiles of BALF from foals and adult horses differed considerably. Significant changes in TNCC and percentages of lymphocytes, macrophages, and eosinophils occurred with age.
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Affiliation(s)
| | - Sandra K Clark
- Departments of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
| | - Jessica M Gilbertie
- Departments of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
| | - Sarah A Wiechert
- Departments of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
| | - Doug E Jones
- Departments of Veterinary Pathology, Iowa State University, Ames, IA, USA
| | - Brett A Sponseller
- Departments of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
- Departments of Veterinary Clinical Sciences, Iowa State University, Ames, IA, USA
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Gonchoroski T, Virginio VG, Thompson CE, Paes JA, Machado CX, Ferreira HB. Evolution and function of the Mycoplasma hyopneumoniae peroxiredoxin, a 2-Cys-like enzyme with a single Cys residue. Mol Genet Genomics 2016; 292:297-305. [PMID: 27858147 DOI: 10.1007/s00438-016-1272-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 11/05/2016] [Indexed: 10/20/2022]
Abstract
The minimal genome of the mollicute Mycoplasma hyopneumoniae, the etiological agent of porcine enzootic pneumonia, encodes a limited repertoire of antioxidant enzymes that include a single and atypical peroxiredoxin (MhPrx), whose evolution and function were studied here. MhPrx has only one catalytic cysteine, in contrast with some of its possible ancestors (2-Cys peroxiredoxins), which have two. Although it is more similar to 2-Cys orthologs, MhPrx can still function with a single peroxidatic cysteine (CysP), using non-thiolic electron donors to reduce it. Therefore, MhPrx could be a representative of a possible group of 2-Cys peroxiredoxins, which have lost the resolving cysteine (CysR) residue without losing their catalytic properties. To further investigate MhPrx evolution, we performed a comprehensive phylogenetic analysis in the context of several bacterial families, including Prxs belonging to Tpx and AhpE families, shedding light on the evolutionary history of Mycoplasmataceae Prxs and giving support to the hypothesis of a relatively recent loss of the CysR within this family. Moreover, mutational analyses provided insights into MhPrx function with one, two, or without catalytic cysteines. While removal of the MhPrx putative CysP caused complete activity loss, confirming its catalytic role, the introduction of a second cysteine in a site correspondent to that of the CysR of a 2-Cys orthologue, as in the MhPrx supposed ancestral form, was compatible with enzyme activity. Overall, our phylogenetic and mutational studies support that MhPrx recently diverged from a 2-Cys Prx ancestor and pave the way for future studies addressing structural, functional, and evolutive aspects of peroxiredoxin subfamilies in Mollicutes and other bacteria.
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Affiliation(s)
- Taylor Gonchoroski
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15005, Porto Alegre, RS, 91501-970, Brazil.,Grupo de Pesquisa em Plasticidade Neuroglial, Departamento de Bioquímica, UFRGS, Porto Alegre, RS, Brazil
| | - Veridiana G Virginio
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15005, Porto Alegre, RS, 91501-970, Brazil
| | - Claudia E Thompson
- Unidade de Biologia Teórica e Computacional, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
| | - Jéssica A Paes
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15005, Porto Alegre, RS, 91501-970, Brazil.,Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
| | - Cláudio X Machado
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15005, Porto Alegre, RS, 91501-970, Brazil.,Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil.,Departamento de Criminalística, Instituto Geral de Perícias do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Henrique B Ferreira
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15005, Porto Alegre, RS, 91501-970, Brazil. .,Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil. .,Departamento de Biologia Molecular e Biotecnologia, Instituto de Biociências, UFRGS, Porto Alegre, RS, Brazil.
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Chaudhuri S, McKenna N, Balce DR, Yates RM. Infection of porcine bone marrow-derived macrophages by porcine respiratory and reproductive syndrome virus impairs phagosomal maturation. J Gen Virol 2015; 97:669-679. [PMID: 26702996 DOI: 10.1099/jgv.0.000384] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV), a positive-sense, ssRNA virus of the genus Arterivirus, is a devastating disease of swine worldwide. Key early targets of PRRSV infection in pigs include professional phagocytes in the lung, such as alveolar and interstitial macrophages and dendritic cells, the dysfunction of which is believed to be responsible for much of the associated mortality. In order to study the effect of virus infection on phagocyte function, the development of a robust, reproducible model would be advantageous. Given the limitations of current models, we set out to develop a porcine bone marrow-derived macrophage (PBMMΦ) cell model to study phagosomal maturation and function during PRRSV infection. Derivation of PBMMΦs from marrow using cultured L929 fibroblast supernatant produced a homogeneous population of cells that exhibited macrophage-like morphology and proficiency in Fc-receptor-mediated phagocytosis and phagosomal maturation. PBMMΦs were permissive to PRRSV infection, resulting in a productive infection that peaked at 24 h. Assessment of the effect of PRRSV infection on the properties of phagosomal maturation in PBMMΦs revealed a significant decrease in phagosomal proteolysis and lowered production of reactive oxygen species, but no change in PBMMΦ viability, phagocytosis or the ability of phagosomes to acidify. In this study, we present a new model to investigate PRRSV infection of phagocytes, which demonstrates a significant effect on phagosomal maturation with the associated implications on proper macrophage function. This model can also be used to study the effect on the phagosomal microenvironment of infection by other viruses targeting porcine macrophages.
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Affiliation(s)
- Sibapriya Chaudhuri
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada
| | - Neil McKenna
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada
| | - Dale R Balce
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada
| | - Robin M Yates
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary AB, T2N 4N1, Canada
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10
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de Almeida-Leite CM, Silva ICC, Galvão LMDC, Arantes RME. Sympathetic glial cells and macrophages develop different responses to Trypanosoma cruzi infection or lipopolysaccharide stimulation. Mem Inst Oswaldo Cruz 2015; 109:459-65. [PMID: 25075784 PMCID: PMC4155848 DOI: 10.1590/0074-0276130492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 06/16/2014] [Indexed: 01/17/2023] Open
Abstract
Nitric oxide (NO) participates in neuronal lesions in the digestive form of Chagas
disease and the proximity of parasitised glial cells and neurons in damaged myenteric
ganglia is a frequent finding. Glial cells have crucial roles in many
neuropathological situations and are potential sources of NO. Here, we investigate
peripheral glial cell response to Trypanosoma cruzi infection to
clarify the role of these cells in the neuronal lesion pathogenesis of Chagas
disease. We used primary glial cell cultures from superior cervical ganglion to
investigate cell activation and NO production after T. cruzi
infection or lipopolysaccharide (LPS) exposure in comparison to peritoneal
macrophages. T. cruzi infection was greater in glial cells, despite
similar levels of NO production in both cell types. Glial cells responded similarly
to T. cruzi and LPS, but were less responsive to LPS than
macrophages were. Our observations contribute to the understanding of Chagas disease
pathogenesis, as based on the high susceptibility of autonomic glial cells to
T. cruzi infection with subsequent NO production. Moreover, our findings
will facilitate future research into the immune responses and activation mechanisms
of peripheral glial cells, which are important for understanding the paradoxical
responses of this cell type in neuronal lesions and neuroprotection.
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Affiliation(s)
- Camila Megale de Almeida-Leite
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
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11
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García-Nicolás O, Quereda JJ, Gómez-Laguna J, Salguero FJ, Carrasco L, Ramis G, Pallarés FJ. Cytokines transcript levels in lung and lymphoid organs during genotype 1 Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) infection. Vet Immunol Immunopathol 2014; 160:26-40. [DOI: 10.1016/j.vetimm.2014.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 03/10/2014] [Accepted: 03/18/2014] [Indexed: 12/24/2022]
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12
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Soerensen KE, Skovgaard K, Heegaard PMH, Jensen HE, Nielsen OL, Leifsson PS, Olsen HG, Aalbaek B, Kristensen AT, Kjelgaard-Hansen M, Wiinberg B, Iburg TM. The impact of Staphylococcus aureus concentration on the development of pulmonary lesions and cytokine expression after intravenous inoculation of pigs. Vet Pathol 2012; 49:950-62. [PMID: 22461225 DOI: 10.1177/0300985812439726] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Acute respiratory distress syndrome is a common complication in severe sepsis. In pigs, the lungs play an important role in clearing systemic bacterial infections due to pulmonary intravascular macrophages found specifically in pigs. However, this increases the exposure of the porcine lungs to pathogens and potential injury. The authors propose that increasing the concentration of the inoculum without changing the bacterial dose will lead to severe sepsis with pronounced pulmonary lesions. This could potentially create a risk of cytokine spillover to the circulation, leading to an increased systemic response. Eight Danish Landrace pigs, approximately 10 weeks old, were inoculated twice with a low or once with a high concentration of Staphylococcus aureus. Three pigs were sham-inoculated. The animals were grouped based on macro- and microscopic lung lesions. The mRNA expression of local pulmonary inflammatory markers was compared to protein levels of systemic inflammatory markers. The most severe pulmonary lesions were observed in animals receiving the high S. aureus concentration, indicating that severity of lesions is dependent on inoculum concentration rather than total numbers of bacteria. Furthermore, local mRNA expression of inflammatory cytokines appeared to be dependent on the magnitude and severity of tissue destruction, including the ability to confine the lesions. Increasing mRNA levels of serum amyloid A could be a confident marker of severity of pulmonary lesions. Since no correlation was observed between local and systemic levels of inflammatory cytokines, this finding could indicate an ability of the porcine lung to compartmentalize the local inflammatory response and thus restrict systemic contribution.
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Affiliation(s)
- K E Soerensen
- Department of Veterinary Disease Biology, Ridebanevej 3, 1870 Frederiksberg, Denmark.
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13
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Mitchell GB, Clark ME, Lu R, Caswell JL. Localization and functional characterization of pulmonary bovine odorant-binding protein. Vet Pathol 2010; 48:1054-60. [PMID: 20826843 DOI: 10.1177/0300985810381907] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Bovine odorant-binding protein (OBP) may function in olfaction and defense against oxidative injury, but its role in inflammation and defense against bacterial infection has not been investigated. Expression of OBP was discovered in the bovine lung and found to undergo changes in abundance during glucocorticoid administration and stress. OBP was localized to nasal, tracheal, and bronchial mucosal glands with immunohistochemistry, with faint expression in airway surface epithelium and none in bronchioles or alveoli. Two isoforms of OBP were identified, appearing to be differentially regulated during lipopolysaccharide-induced pulmonary inflammation, but differences between these isoforms were not revealed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Functional studies showed no effect of OBP on in vitro growth of Escherichia coli or Mannheimia haemolytica under iron-replete or iron-depleted conditions, nor did OBP opsonize bacteria for an enhanced neutrophil oxidative burst. However, OBP did reduce the ability of supernatants from lipopolysaccharide-stimulated macrophages to induce neutrophil chemotaxis. These findings indicate that OBP may inhibit neutrophil recruitment by inflammatory mediators, and they suggest an ability to bind macrophage-derived inflammatory mediators within the airways.
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Affiliation(s)
- G B Mitchell
- Department of Pathobiology, University of Guelph, Guelph, ON, Canada
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14
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Machado CX, Pinto PM, Zaha A, Ferreira HB. A peroxiredoxin from Mycoplasma hyopneumoniae with a possible role in H2O2 detoxification. MICROBIOLOGY-SGM 2009; 155:3411-3419. [PMID: 19589831 DOI: 10.1099/mic.0.030643-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mycoplasma hyopneumoniae is the causative agent of porcine enzootic pneumonia, which affects pig farms worldwide, causing heavy economic losses. In the infection process, this bacterium is exposed to reactive oxygen species (ROS) from its own metabolism or generated by the host as one of the strategies used to neutralize the pathogen. Although the presence of classical antioxidant enzymes would be expected in M. hyopneumoniae, important genes directly related to protection against ROS, such as superoxide dismutase, catalases and glutathione peroxidase, have not been identified by sequence homology in the genome sequence annotation. Among the few identified M. hyopneumoniae genes coding for proteins possibly involved with suppression of ROS-mediated damage, one (tpx) coding for a peroxiredoxin (MhPrx) has been recognized. The sequence and phylogenetic analyses perfomed in this study indicate that MhPrx is closely related to the atypical 2-Cys peroxiredoxin subfamily, although it has only one cysteine in its sequence. The MhPrx coding DNA sequence was cloned and expressed in Escherichia coli to produce a recombinant MhPrx (rMhPrx), which was purified and used to immunize mice and produce an anti-MhPrx polyclonal antiserum. Probing of M. hyopneumoniae extracts with this antiserum demonstrated that MhPrx is expressed in all three tested strains (J, 7422 and 7448). Cross-linking assays and size-exclusion chromatography indicate that rMhPrx forms dimers, as has been established for atypical 2-Cys peroxiredoxins. Furthermore, a metal-catalysed oxidation system was used to assay the activity of rMhPrx, showing that it can protect DNA from ROS-mediated damage and may play an essential role during infection.
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Affiliation(s)
- Cláudio X Machado
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
| | - Paulo M Pinto
- Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
| | - Arnaldo Zaha
- Departamento de Biologia Molecular e Biotecnologia, Instituto de Biociências, UFRGS, Porto Alegre-RS, Brazil.,Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
| | - Henrique B Ferreira
- Departamento de Biologia Molecular e Biotecnologia, Instituto de Biociências, UFRGS, Porto Alegre-RS, Brazil.,Laboratório de Genômica Estrutural e Funcional, Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
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15
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LO DY, HUNG CN, LEE WC, LIAO JW, BLACKLAWS BA, CHEN TH, CHIEN MS, HSUAN SL. Effect of Immunostimulation by Detoxified E. coli Lipopolysaccharide Combined with Inactivated Propionibacterium granulosum Cells on Porcine Immunity. J Vet Med Sci 2009; 71:897-903. [DOI: 10.1292/jvms.71.897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Dan-Yuan LO
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
- Department of Veterinary Medicine, National Chiayi University
| | - Chien-Ning HUNG
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
| | - Wei-Cheng LEE
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
| | - Jiunn-Wang LIAO
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
| | - Barbara A BLACKLAWS
- Centre of Veterinary Science, Department of Veterinary Medicine, Cambridge University
| | - Ter-Hsin CHEN
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
| | - Maw-Sheng CHIEN
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
| | - Shih-Ling HSUAN
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University
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16
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Rogers CS, Abraham WM, Brogden KA, Engelhardt JF, Fisher JT, McCray PB, McLennan G, Meyerholz DK, Namati E, Ostedgaard LS, Prather RS, Sabater JR, Stoltz DA, Zabner J, Welsh MJ. The porcine lung as a potential model for cystic fibrosis. Am J Physiol Lung Cell Mol Physiol 2008; 295:L240-63. [PMID: 18487356 DOI: 10.1152/ajplung.90203.2008] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Airway disease currently causes most of the morbidity and mortality in patients with cystic fibrosis (CF). However, understanding the pathogenesis of CF lung disease and developing novel therapeutic strategies have been hampered by the limitations of current models. Although the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) has been targeted in mice, CF mice fail to develop lung or pancreatic disease like that in humans. In many respects, the anatomy, biochemistry, physiology, size, and genetics of pigs resemble those of humans. Thus pigs with a targeted CFTR gene might provide a good model for CF. Here, we review aspects of porcine airways and lung that are relevant to CF.
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Affiliation(s)
- Christopher S Rogers
- Department of Internal Medicine, Roy J. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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17
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Zelnickova P, Leva L, Stepanova H, Kovaru F, Faldyna M. Age-dependent changes of proinflammatory cytokine production by porcine peripheral blood phagocytes. Vet Immunol Immunopathol 2008; 124:367-78. [PMID: 18534689 DOI: 10.1016/j.vetimm.2008.04.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 04/04/2008] [Accepted: 04/23/2008] [Indexed: 11/19/2022]
Abstract
The aim of the present study was to determine postnatal ontogeny of proinflammatory cytokines IL-1beta, IL-8 and TNF-alpha production by in vitro stimulated porcine blood leukocytes. Four age categories of pigs were chosen. Cytokine production was determined using intracellular flow cytometry. It was found that IL-8 and TNF-alpha production by blood monocytes significantly increased during the postnatal period while production of IL-1beta remained unchanged. In blood neutrophils, the IL-8 production increased only during the postnatal period, while the levels of TNF-alpha and IL-1beta were undetectable during the whole postnatal period. Generally, the most intensive changes in cytokine production occurred before weaning. The production of low levels of cytokines by monocytes and neutrophils from young pigs was not caused by a delayed cytokine response because the cytokine production after 8-h stimulation was lower than that after 4-h stimulation in all age categories. The ontogenetical changes showed the same trends when two different stimulators (LPS, heat-inactivated E. coli) were used, suggesting that the ontogenetical changes are not caused by a simple defect in one signalling pathway, but it is probably a more complex process. No differences in cytokine production between the whole blood and the isolated cells supplemented with newborn or adult serum were found. Thus the ability of newborn monocytes and neutrophils to produce proinflammatory cytokines was not decreased due to the influence of composition of the microenvironment, where the cells were present. In conclusion, the ability of porcine blood leukocytes to produce cytokines develops during postnatal life.
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Affiliation(s)
- Petra Zelnickova
- Department of Immunology, Veterinary Research Institute, Hudcova 70, 621 00 Brno, Czech Republic
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18
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Lauridsen C, Stagsted J, Jensen SK. n-6 and n-3 fatty acids ratio and vitamin E in porcine maternal diet influence the antioxidant status and immune cell eicosanoid response in the progeny. Prostaglandins Other Lipid Mediat 2007; 84:66-78. [PMID: 17643889 DOI: 10.1016/j.prostaglandins.2007.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 04/10/2007] [Accepted: 04/18/2007] [Indexed: 11/28/2022]
Abstract
Five groups of lactating sows were fed diets containing 8% of either added rapeseed oil, fish oil or sunflower oil and 60 mg vitamin E/kg feed, or the diets with sunflower oil and fish oil, respectively, supplemented with 500 mg vitamin E/kg. Supplementation of vitamin E to the sows increased the concentration of alpha-tocopherol of the muscle, and addition of sunflower oil decreased the activity of glutathione peroxidase in liver cytosol compared to fish oil and rapeseed oil. The composition of fatty acids of alveolar macrophages (AM) of piglets was influenced by the dietary fat sources provided the sows, i.e., the ratio of n-6:n-3 fatty acids was highest in AM of piglets suckling sows of the sunflower oil treatments, and lowest in AM of piglets suckling sows fed fish oil with the rapeseed oil treatment in between. The ex vivo synthesis of prostaglandin E(2) and thromboxane B(2) in AM of piglets suckling sows fed sunflower oil was elevated compared to piglets suckling sows fed fish oil. Vitamin E supplementation to sows enhanced the synthesis of these eicosanoids, and also the concentration of alpha-tocopherol in the AM of the piglets.
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Affiliation(s)
- Charlotte Lauridsen
- Department of Animal Health, Welfare and Nutrition, Aarhus University, Research Centre Foulum, PO Box 50, DK-8830 Tjele, Denmark.
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19
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Almeida-Leite CMD, Galvão LMDC, Afonso LCC, Cunha FDQ, Arantes RME. Interferon-γ induced nitric oxide mediates in vitro neuronal damage by Trypanosoma cruzi-infected macrophages. Neurobiol Dis 2007; 25:170-8. [PMID: 17056264 DOI: 10.1016/j.nbd.2006.09.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Revised: 09/01/2006] [Accepted: 09/05/2006] [Indexed: 11/21/2022] Open
Abstract
Neuronal lesions and peripheral denervation in Chagas' disease are related to local inflammation; however, the pathogenic mechanisms of neuronal lesions in the heart and megavisceras are still unclear. We investigated the involvement of nitric oxide (NO) on neuronal lesion in co-cultures of neurons and macrophages. Trypanosoma cruzi-infected and interferon-gamma (IFN-gamma)-activated co-cultures of neurons and wild-type (WT) macrophages showed significant reduction of both neuronal survival and neurite density. These findings correlated with the levels of NO and the expression of inducible nitric oxide synthase (iNOS). Accordingly, neuronal survival rate in the co-cultures was recovered to control levels by treatment of the cultures with the iNOS inhibitor, aminoguanidine. Moreover, neither neuronal survival nor the neurite density was affected in the co-cultures when the macrophages were harvested from iNOS-deficient mice. These results demonstrate that iNOS-derived NO is the major molecule involved in neuronal damage mechanism in our in vitro model of Chagas' disease neuropathology.
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Affiliation(s)
- Camila Megale de Almeida-Leite
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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20
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Hodgson JC, Watkins CA, Bayne CW. Contribution of respiratory burst activity to innate immune function and the effects of disease status and agent on chemiluminescence responses by ruminant phagocytes in vitro. Vet Immunol Immunopathol 2006; 112:12-23. [PMID: 16678912 DOI: 10.1016/j.vetimm.2006.03.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The mechanisms of interaction between phagocytes and different bacteria that help resolve lung infections or contribute to lung pathology are poorly defined. Alveolar phagocytes (resident macrophages and recruited neutrophils) make a major contribution to innate immunity by mounting a respiratory burst that helps kill internalised bacteria. However, this ability may be altered during or after exposure to infection. This review considers the application and limitations of a variety of analytical methods for oxygen-dependent mechanisms of respiratory burst in phagocytes initiated by soluble and particulate activators. Particular reference is given to the study in vitro of phagocytes from healthy and diseased ruminants during either natural infection with Mycobacterium avium paratuberculosis or experimental infection with Pasteurella multocida or Mannheimia haemolytica.
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Affiliation(s)
- J C Hodgson
- Moredun Research Institute, International Research Centre, Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, United Kingdom.
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21
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Lo DY, Chien MS, Yeh KS, Koge K, Lin CC, Hsuan SL, Lee WC. Effects of sugar cane extract on pseudorabies virus challenge of pigs. J Vet Med Sci 2006; 68:219-25. [PMID: 16598164 DOI: 10.1292/jvms.68.219] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This experiment aimed to evaluate the efficacy of sugar cane extract (SCE) on the modulation of porcine immunity against pseudorabies virus (PrV) infection. Twelve-week-old experimental pigs were fed with SCE (500 mg/kg of body weight per day) for 3 days and challenged with PrV (2 x 10(5) TCID(50)) on the second day. Pigs that were only challenged with PrV and without SCE-treatment served as controls. The leukocyte functional assays were performed on the 7th and 14th day post-PrV challenge. Our results showed a significant enhancement (P<0.05) of natural killer cytotoxicity, lymphocyte proliferation, phagocytic function of monocytes, and interferon-gamma (IFN-gamma) production of CD4(+) and gammadelta T cells in the SCE-treated pigs compared with the controls. In addition, SCE administration reduced the severity of clinical signs and brain lesion in the course of disease in PrV-challenged pigs. SCE-treated pigs showed a 12% growth enhancement compared with untreated controls. SCE administration had an immunostimulating effect on porcine immunity that may subsequently enhance protective activities against PrV infection which may be extensively applied in field for the prevention of infections.
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Affiliation(s)
- Dan-Yuan Lo
- Graduate Institute of Veterinary Pathology, National Chung Hsing University, 402 Taichung, Japan
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22
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Lo DY, Chen TH, Chien MS, Koge K, Hosono A, Kaminogawa S, Lee WC. Effects of sugar cane extract on the modulation of immunity in pigs. J Vet Med Sci 2005; 67:591-7. [PMID: 15997186 DOI: 10.1292/jvms.67.591] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The experiment was aimed to test the efficacy of sugar cane extract (SCE) on the modulation of pig immunity under field conditions. The SCE preparation consisted of sugar cane extract (20%) and oilcake of rice bran (80%). SCE (500 mg/kg of body weight per day) was fed to weanling pigs on 3 consecutive days per week for 4 weeks. The results showed a significant enhancement of cytotoxicity of natural killer (NK) cells and phagocytosis by neutrophils and monocytes, compared to untreated pigs. The enhancement of NK cell function may have protected against porcine reproductive respiratory syndrome (PRRS), as there was a reduction in seroconversion rates in treated pigs. Moreover, SCE-treated pigs showed a 7.87% growth enhancement compared with untreated controls. Thus SCE produces an immunostimulative effect on porcine innate immunity that may provide protection against pathogens.
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Affiliation(s)
- Dan-Yuan Lo
- Graduate Institute of Veterinary Pathology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan, R.O.C
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23
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Lauridsen C, Jensen SK. Influence of supplementation of all-rac-α-tocopheryl acetate preweaning and vitamin C postweaning on α-tocopherol and immune responses of piglets1. J Anim Sci 2005; 83:1274-86. [PMID: 15890805 DOI: 10.2527/2005.8361274x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study was designed to test whether dietary maternal supplementation of all-rac-alpha-tocopheryl acetate during lactation and dietary vitamin C supplementation after weaning could increase the alpha-tocopherol status pre- and postweaning and the immune responses of piglets postweaning. The experiment involved 12 crossbred sows that were fed increasing levels of all-rac-alpha-tocopheryl (70, 150, and 250 IU/kg, as-fed basis) during lactation. After weaning (d 28 of age), litters were divided into two groups that were supplemented with or without vitamin C (500 mg/kg of feed, as-fed basis). Milk and blood samples were obtained from the sows during lactation. Pigs were bled at 4, 16, 28, 35, 42, and 49 d of age. Liver, heart, muscle, and s.c. adipose tissues were collected (on 28, 35, 42, and 49 d of age) and analyzed for alpha-tocopherol. On the same days, alveolar macrophages of the lungs were collected, and analyzed for the concentration of alpha-tocopherol and its stereoisomer composition, fatty acid composition, and release of prostaglandin E2, leukotriene B4, and thromboxane B2. Increasing dietary all-rac-alpha-tocopheryl acetate concentration increased the concentration of alpha-tocopherol in plasma (P = 0.02) and milk (P = 0.007) of sows, and the sow milk concentrations of alpha-tocopherol and vitamin A were greater on d 2 of lactation than later on during lactation. The plasma concentration of alpha-tocopherol in piglets decreased from d 4 to later on during suckling (P < 0.001) and again as the postweaning period progressed (P < 0.001). When lipid-standardized, plasma alpha-tocopherol was increased in piglets of sows fed 250 IU of all-rac-alpha-tocopheryl acetate compared with other sow-groups (P = 0.005). At 28 d of age, alpha-tocopherol concentrations in tissues were increased with supplementation of the high dietary all-rac-alpha-tocopheryl acetate levels to the sows; however, after weaning, a decrease in alpha-tocopherol concentration in most tissues (except liver) was observed, but the decrease tended to be less in the muscle (P = 0.099) and adipose tissue (P = 0.11) of piglets suckling sows fed 150 and 250 IU of all-rac-alpha-tocopheryl acetate. Vitamin C supplementation after weaning increased liver alpha-tocopherol (P = 0.01) and serum immunoglobulin M concentration (P = 0.04), and vitamin C supplementation increased the proportion of the RRR-alpha-tocopherol (P = 0.03) at the expense of the RRS-stereoisomer form (P = 0.05) of alpha-tocopherol in alveolar macrophages of the piglets. In conclusion, this study on maternal all-rac-alpha-tocopheryl acetate and postweaning vitamin C supplementation suggests a nutritional strategy for increasing alpha-tocopherol status and immune responses of weaned piglets.
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Affiliation(s)
- C Lauridsen
- Department of Animal Health, Welfare and Nutrition, Research Centre Foulum, Denmark.
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24
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Begni B, Amadori M, Ritelli M, Podavini D. Effects of IFN-α on the Inflammatory Response of Swine Leukocytes to Bacterial Endotoxin. J Interferon Cytokine Res 2005; 25:202-8. [PMID: 15812246 DOI: 10.1089/jir.2005.25.202] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Because low-dose interferon-alpha (IFN-alpha) treatment had proved effective in several models of chronic inflammation and autoimmune disease, a possible role of IFN-alpha in modulating the response of swine leukocytes to bacterial endotoxin was investigated in this study. Exposure of swine peripheral blood mononuclear cells (PBMC) to low concentrations of human IFN-alpha caused a strong, dose-dependent decrease in CD14 expression, the lowest level being observed at 5 U/ml IFN-alpha. This result was confirmed if PBMC were later exposed to purified lipopolysaccharide (LPS). A 10-fold lower IFN-alpha concentration (0.5 U/ml) caused the largest reduction of tumor necrosis factor-alpha (TNF-alpha) accumulation in the medium of pulmonary alveolar macrophages (PAM), stimulated with bacterial LPS. At 0.5 U/ml, the expression of the TNF-alpha gene in PAM was also strongly reduced, as opposed to cells pretreated with 50 U/ml IFN-alpha. In contrast, expression of the interleukin-1beta (IL- 1beta) gene was stimulated and that of the IL-6 gene was not significantly affected at both IFN-alpha concentrations. Results point to an important role of IFN-alpha in control of the inflammatory response to bacterial endotoxin in pigs.
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Affiliation(s)
- Barbara Begni
- Department of Immunoprophylaxis and Animal Welfare, Istituto Zooprofilattico Sperimentale, 25124 Brescia, Italy
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25
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Lee SM, Schommer SK, Kleiboeker SB. Porcine reproductive and respiratory syndrome virus field isolates differ in in vitro interferon phenotypes. Vet Immunol Immunopathol 2004; 102:217-31. [PMID: 15507307 PMCID: PMC7112598 DOI: 10.1016/j.vetimm.2004.09.009] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Type I interferons (IFN-α and -β) play an important role in the innate host defense against viral infection by inducing antiviral responses. In addition to direct antiviral activities, type I IFN serves as an important link between the innate and adaptive immune response through multiple mechanisms. Therefore, the outcome of a viral infection can be affected by IFN induction and the IFN sensitivity of a virus. North American porcine reproductive and respiratory syndrome virus (PRRSV) field isolates were studied with regard to IFN-α sensitivity and induction in order to understand the role of type I IFN in PRRSV pathogenesis. PRRSV isolates were differentially sensitive to porcine recombinant IFN-α (rIFN-α) and varied in their ability to induce IFN-α in porcine alveolar macrophages (PAM) cultures as measured by a porcine IFN-α specific ELISA on cell culture supernatants. Fifty-two plaques were purified from three PRRSV isolates (numbers 3, 7, and 12) and tested for IFN sensitivity and IFN induction. Plaque-derived populations were composed of heterogeneous populations in terms of IFN-inducing capacity and sensitivity to rIFN-α. When macrophages infected with isolates 3, 7, or 12 were treated with polycytidylic acid (polyI:C), IFN-α production was enhanced. Cells infected with isolate 3 and treated with polyI:C showed the most consistent and strongest enhancement of IFN-α production. It was demonstrated that the relatively low concentrations of IFN-α produced by isolate 3 contributed to the enhanced IFN-α synthesis in response to polyI:C. Isolates 7 and 12 significantly suppressed the enhanced IFN-α production by isolate 3 in polyI:C treated cells. To determine if suppression was at the level of IFN-α transcription, quantitative RT-PCR was performed for IFN-α mRNA and compared to GAPDH and cyclophilin mRNA quantification. However, the relative number of IFN-α transcript copies did not correlate with IFN-α protein levels, suggesting a post-transcriptional mechanism of suppression. In summary, these results demonstrate that PRRSV field isolates differ both in IFN-α sensitivity and induction. Furthermore, a PRRSV field isolate strongly enhance polyI:C-induced IFN-α production in PAM cultures and this priming effect was suppressed by other PRRSV isolates.
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Affiliation(s)
- Sang-Myeong Lee
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, 1600 E. Rollins, Columbia, MO 65211, USA
| | - Susan K. Schommer
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, 1600 E. Rollins, Columbia, MO 65211, USA
- Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, 1600 E. Rollins, Columbia, MO 65211, USA
| | - Steven B. Kleiboeker
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, 1600 E. Rollins, Columbia, MO 65211, USA
- Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, 1600 E. Rollins, Columbia, MO 65211, USA
- Corresponding author. Tel.: +1 573 882 6811; fax: +1 573 882 1411.
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Francoz D, Lapointe JM, Wellemans V, Desrochers A, Caswell JL, Stott JL, Dubreuil P. Immunoglobulin G2 deficiency with transient hypogammaglobulinemia and chronic respiratory disease in a 6-month-old Holstein heifer. J Vet Diagn Invest 2004; 16:432-5. [PMID: 15460327 DOI: 10.1177/104063870401600511] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A 6-month-old Holstein heifer that was nonresponsive to medical treatment was evaluated for chronic respiratory disease. Complete blood count and serum chemistry revealed neutrophilic leukocytosis and low globulin levels. Assays for bovine leukemia virus, bovine virus diarrhea, and bovine leukocyte adhesion deficiency were negative. Serum globulin subclass assays revealed transient low concentrations of immunoglobulin (Ig) G1 and IgA, persistent low IgG2, and subnormal IgM. Vaccination with 2 doses of multiple, inactived viruses induced seroconversion for most viruses. Flow cytometric analysis of blood lymphocyte subpopulation demonstrated an increase in CD5+ B-cells. Blood lymphocyte proliferation and neutrophil function tests were normal. Results of immunologic assays indicated IgG2 deficiency with transient hypogammaglobulinemia.
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Affiliation(s)
- David Francoz
- Département des Sciences Cliniques , Faculté de Médecine Vétérinaire, Université de Montréal, Case postale 5000, Saint Hyacinthe, Québec, Canada J2S 7C6
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Riber U, Nielsen J, Lind P. In utero infection with PRRS virus modulates cellular functions of blood monocytes and alveolar lung macrophages in piglets. Vet Immunol Immunopathol 2004; 99:169-77. [PMID: 15135983 DOI: 10.1016/j.vetimm.2004.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2003] [Revised: 01/29/2004] [Accepted: 02/04/2004] [Indexed: 11/25/2022]
Abstract
The putative immunosuppressive effect of PRRS virus (PRRSV) on innate immune responses was studied in piglets infected in utero with PRRSV. Phagocytosis and oxidative burst capacities in 2-, 4- and 6-week-old in utero infected piglets were investigated and compared with age-matched control piglets. Phagocytic capacity of blood monocytes against Salmonella bacteria was investigated by flow cytometry. Oxidative burst in blood monocytes and in alveolar lung macrophages was investigated by luminol- and lucigenin-enhanced chemiluminescence, respectively. Decreased phagocytosis against Salmonella was found in blood monocytes from 4- and 6-week-old infected piglets compared to controls. In contrast, 2-week-old infected piglets showed phagocytic responses comparable to age matched control piglets. While oxidative burst capacity was increased in blood (PBMC) from in utero PRRSV infected piglets, the oxidative burst capacity of alveolar lung macrophages was decreased, especially in 2- and 4-week-old piglets, compared to age-matched control piglets. The present results indicate that in utero infection with PRRSV inhibits phagocytosis against Salmonella in blood monocytes as well as the oxidative burst capacity of alveolar macrophages. These observations indicate that PRRSV in utero infection induces at state of immunosuppression in piglets paving the way for enhanced secondary infections.
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Affiliation(s)
- Ulla Riber
- Department of Veterinary Diagnostics and Research, Danish Institute for Food and Veterinary Research, Bülowsvej 27, 1790 Copenhagen V, Denmark.
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Lun S, Willson PJ. Expression of green fluorescent protein and its application in pathogenesis studies of serotype 2 Streptococcus suis. J Microbiol Methods 2004; 56:401-12. [PMID: 14967232 DOI: 10.1016/j.mimet.2003.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Revised: 11/06/2003] [Accepted: 11/11/2003] [Indexed: 11/15/2022]
Abstract
We investigated the interaction between type 2 Streptococcus suis and swine phagocytes during infection of the natural host, by using green fluorescent protein (GFP) as a specific marker to observe the challenge organism. We compared the strength of the S. suis sly promoter (SP332) and the synthetic promoter (CP25) in driving GFP expression. Two GFP alleles, gfpP11 and gfpmut3*, were also compared. The two promoters and two alleles were efficiently compared using three different promoter-GFP gene combinations on a shuttle vector, which were transformed into S. suis strains SX332, SX932 or M2. Plasmid pSL6.81 has SP332 with gfpP11, pSL5.24 has SP332 with gfpmut3*, and pSL5.28 has CP25 with gfpmut3*. The transformants were fluorescent with green light when viewed with an epifluorescence microscope or during flow cytometry. The signal was also detected using a laser scanning confocal microscope. The GFP expression level varied and CP25 with gfpmut3* led to greatest expression. For optimizing GFP detection, fluorescence-based cell sorting was applied to SX332(pSL5.28) and the mean fluorescence intensity increased 25.9% after optimization. Fluorescence activated cell sorting (FACS)-based phagocytosis assay showed that, without opsonization, phagocytosis rates of SX332, SX932 and M2 by both neutrophils and monocytes were similar and low. After opsonization, the phagocytosis of M2 increased 10-fold while phagocytosis of SX332 and SX932 did not change. GFP-labeled S. suis was identified in fresh pig tonsil tissue 18 h after infection. The results of this study indicated that GFP was expressed in type 2 S. suis and GFP labeled S. suis could be used in phagocytosis and pathogenesis studies.
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Affiliation(s)
- Shichun Lun
- Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Canada
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Kampen AH, Tollersrud T, Larsen S, Roth JA, Frank DE, Lund A. Repeatability of flow cytometric and classical measurement of phagocytosis and respiratory burst in bovine polymorphonuclear leukocytes. Vet Immunol Immunopathol 2004; 97:105-14. [PMID: 14700542 DOI: 10.1016/j.vetimm.2003.08.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Five methods for measurement of phagocytosis and respiratory burst activity of bovine blood polymorphonuclear leukocytes (PMNs) were evaluated. Eight cows were repeatedly sampled over a two week period and parallel samples tested in all five assays to assess the repeatability and stability of the methods. In the flow cytometric phagocytosis assay, ingestion of fluorescein labeled bacteria was measured, and in the flow cytometric assay for respiratory burst, oxidation of a dye by reactive oxygen species was recorded. In the classical assays, bactericidal effect on opsonized, live bacteria was quantified by the conversion of an indicator substance, superoxide anion production was assayed by the reduction of cytochrome c, whereas myeloperoxidase activity was determined with a radioactive iodination assay. The results showed that the Phagotest, Bursttest, cytochrome c and iodination assays gave repeatable results when samples were run in the same setup on the same day. Although day-to-day variability was significant in all assays, the described methods comprise a panel of useful tests for the evaluation of phagocytosis and respiratory burst activity in bovine PMNs. The flow cytometric methods represent a convenient alternative to the classical methods for measurement of phagocytosis and respiratory burst in bovine blood PMNs.
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Affiliation(s)
- Annette H Kampen
- National Veterinary Institute, P.O. Box 8156 Dep., N-0033 Oslo, Norway.
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Mitchell GB, Albright BN, Caswell JL. Effect of interleukin-8 and granulocyte colony-stimulating factor on priming and activation of bovine neutrophils. Infect Immun 2003; 71:1643-9. [PMID: 12654776 PMCID: PMC152050 DOI: 10.1128/iai.71.4.1643-1649.2003] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neutrophils are important effector cells in innate and acquired immunity, but the magnitude and character of their phagocytic and bactericidal responses depend on cues derived from mediators in the local microenvironment. This study investigated the effect of bovine interleukin-8 (IL-8) and granulocyte colony-stimulating factor (G-CSF) on priming and activation of bovine neutrophils in vitro and in vivo. Neutrophils were isolated from blood and cultured for up to 18 h, with or without cytokines, and then Mannheimia haemolytica-induced oxidative burst and phagocytosis of Staphylococcus aureus were measured by flow cytometry. Neither IL-8 nor G-CSF directly triggered an oxidative burst, but incubation with these cytokines for 18 h primed neutrophils for a greater oxidative burst triggered by M. haemolytica and for enhanced uptake of S. aureus. The maximal response was observed when neutrophils were incubated with both cytokines together, at concentrations of 200 ng/ml for G-CSF and 400 ng/ml for IL-8. The IL-8-induced priming effect was reduced by treatment with a neutralizing antibody to IL-8, and was not attributed to endotoxin contamination. Instillation of IL-8 into the lung using a bronchoscope induced neutrophil recruitment within 18 h. Neutrophils from IL-8-treated lung showed dose-dependent enhancement of the oxidative burst triggered by M. haemolytica. Histologically, neutrophils filled alveoli and bronchioles, and scattered macrophages contained neutrophils with morphological features of apoptosis. Thus, prolonged in vitro or in vivo exposure to IL-8 and/or G-CSF enhances the subsequent oxidative burst and phagocytic responses of bovine neutrophils.
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Affiliation(s)
- Gordon B Mitchell
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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