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Han Z, Zhang Y, Wang C, Liu X, Jiang A, Liu Z, Wang J, Yang Z, Wei Z. Ochratoxin A-Triggered Chicken Heterophil Extracellular Traps Release through Reactive Oxygen Species Production Dependent on Activation of NADPH Oxidase, ERK, and p38 MAPK Signaling Pathways. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:11230-11235. [PMID: 31523955 DOI: 10.1021/acs.jafc.9b03155] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Ochratoxin A (OTA) is a mycotoxin which could cause strong immunosuppressive toxicological effects in animals and humans. Heterophil extracellular traps (HETs) as a novel defense of chicken heterophils play an important role against pathogen infection. It has been reported that OTA can weaken the phagocytosis function of neutrophils. However, whether or not OTA shows immunosuppressive effects on HET release remains unclear. In the present study, we aim to first investigate the effects of OTA on HET release and then try to clarify the mechanisms in this process. OTA-induced HET structures were observed and analyzed by fluorescence confocal microscopy. The quantitative determination of OTA-induced HETs was measured by PicoGreen and a fluorescence microplate. The results clearly showed that OTA obviously induced the release of HET-like structures in heterophils, and these extracellular networks were composed by chromatin decorated with histones and neutrophil elastase. Reactive oxygen species (ROS) production was also increased in the process of OTA-induced HET formation. Furthermore, the inhibitors of NADPH oxidase, ERK [Formula: see text], and p38 MAPK signaling pathways significantly decreased OTA-induced HET formation. The abovementioned results suggest that OTA-induced HET formation is related to ROS production dependent on the activation of NADPH oxidase, ERK [Formula: see text], and p38 MAPK signaling pathways. Taken together, this study first shows that OTA possesses the ability to trigger HET formation, which provides our understanding of the host that continuously suffered OTA exposure leading to the hyporeactivity of the immune system against infection.
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Affiliation(s)
- Zhen Han
- School of Life Sciences and Engineering , Foshan University , Foshan 528225 , Guangdong Province , China
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Yong Zhang
- School of Life Sciences and Engineering , Foshan University , Foshan 528225 , Guangdong Province , China
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Chaoqun Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Xiao Liu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Aimin Jiang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Ziyi Liu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Jingjing Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine , Jilin University , Changchun 130062 , Jilin Province , PR China
| | - Zhengtao Yang
- School of Life Sciences and Engineering , Foshan University , Foshan 528225 , Guangdong Province , China
| | - Zhengkai Wei
- School of Life Sciences and Engineering , Foshan University , Foshan 528225 , Guangdong Province , China
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Kogut MH, Swaggerty CL, Chiang HI, Genovese KJ, He H, Zhou H, Arsenault RJ. Critical Role of Glycogen Synthase Kinase-3β in Regulating the Avian Heterophil Response to Salmonella enterica Serovar Enteritidis. Front Vet Sci 2014; 1:10. [PMID: 26664916 PMCID: PMC4672156 DOI: 10.3389/fvets.2014.00010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 09/29/2014] [Indexed: 11/13/2022] Open
Abstract
A microarray-assisted gene expression screen of chicken heterophils revealed glycogen synthase kinase-3β (GSK-3β), a multifunctional Ser/Thr kinase, to be consistently upregulated 30–180 min following stimulation with Salmonella enterica serovar Enteritidis (S. Enteritidis). The present study was designed to delineate the role of GSK-3β in regulating the innate function of chicken heterophils in response to S. Enteritidis exposure. Using a specific GSK-3β ELISA assay, 30 min after infection with S. Enteritidis, heterophils had a significant decrease (p ≤ 0.05) in total GSK-3β, but a significant increase (p ≤ 0.05) in phosphorylated GSK-3β (Ser9). By 60 min post-infection, there was no difference in the amount of phosphorylated GSK-3β (Ser9) in either the uninfected and infected heterophils. S. Enteritidis interaction with heterophils alters GSK-3β activity by stimulating phosphorylation at Ser9 and that peaks by 30 min post-infection. Further, inhibition of GSK3β with lithium chloride resulted in a significant decrease (p ≤ 0.05) in NF-κB activation and expression of IL-6, but induces a significant increase (p ≤ 0.05) in the expression of the anti-inflammatory cytokine, IL-10. Using a phospho-specific antibody array confirmed the phosphorylation of GSK-3β (Ser9) as well as the phosphorylation of the downstream cytokine-activated intracellular signaling pathway involved in stimulating immune responses, IκB, the IκB subunit IKK-β, and the NF-κB subunits p105, p65, and c-Rel. Our data revealed that the phosphorylation of GSK-3β (Ser9) is responsible for inducing and controlling an innate response to the bacteria. Our findings suggest that the repression of GSK-3 activity is beneficial to the host cell and may act as a target for treatment in controlling intestinal colonization in chickens. Further experiments will define the in vivo modulation of GSK-3 as a potential alternative to antibiotics in salmonella and other intestinal bacterial infections.
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Affiliation(s)
- Michael H Kogut
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture , College Station, TX , USA
| | - Christina L Swaggerty
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture , College Station, TX , USA
| | - Hsin-I Chiang
- Department of Animal Sciences, National Chung Hsing University , Taichung , Taiwan
| | - Kenneth J Genovese
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture , College Station, TX , USA
| | - Haiqi He
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture , College Station, TX , USA
| | - Huaijun Zhou
- Department of Animal Science, University of California Davis , Davis, CA , USA
| | - Ryan J Arsenault
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture , College Station, TX , USA
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Genovese KJ, He H, Swaggerty CL, Kogut MH. The avian heterophil. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 41:334-340. [PMID: 23583524 DOI: 10.1016/j.dci.2013.03.021] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 03/27/2013] [Accepted: 03/28/2013] [Indexed: 06/02/2023]
Abstract
Heterophils play an indispensable role in the immune defense of the avian host. To accomplish this defense, heterophils use sophisticated mechanisms to both detect and destroy pathogenic microbes. Detection of pathogens through the toll-like receptors (TLR), FC and complement receptors, and other pathogen recognition receptors has been recently described for the avian heterophil. Upon detection of pathogens, the avian heterophil, through a network of intracellular signaling pathways and the release and response to cytokines and chemokines, responds using a repertoire of microbial killing mechanisms including production of an oxidative burst, cellular degranulation, and production of extracellular matrices of DNA and histones (HETs). In this review, the authors describe the recent advances in our understanding of the avian heterophil, its functions, receptors and signaling, identified antimicrobial products, cytokine and chemokine production, and some of the effects of genetic selection on heterophils and their functional characteristics.
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Affiliation(s)
- Kenneth J Genovese
- U.S. Department of Agriculture, Agricultural Research Service, Food and Feed Safety Research Unit, College Station, TX 77845, USA.
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Brownlie R, Allan B. Avian toll-like receptors. Cell Tissue Res 2010; 343:121-30. [DOI: 10.1007/s00441-010-1026-0] [Citation(s) in RCA: 184] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 07/21/2010] [Indexed: 11/28/2022]
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GERILECHAOGETU, HANIEH H, ABE A, KONDO Y. Extracellular signal-regulated kinase (ERK) activation in chicken heterophils stimulated with phorbol 12-myristate 13-acetate (PMA), Formyl-methionylleucyl-phenylalanine (fMLP) and lipopolysaccharide (LPS). Anim Sci J 2009; 80:577-84. [DOI: 10.1111/j.1740-0929.2009.00674.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Exercise-induced extracellular 72 kDa heat shock protein (Hsp72) stimulates neutrophil phagocytic and fungicidal capacities via TLR-2. Eur J Appl Physiol 2009; 108:217-25. [PMID: 19771447 DOI: 10.1007/s00421-009-1201-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2009] [Indexed: 10/20/2022]
Abstract
This study evaluated the role of toll like receptor 2 (TLR-2) in the interaction of 72 kDa extracellular heat shock protein (Hsp72, a stress-inducible protein) with neutrophils and the participation on TLR-2 in the stimulation of neutrophil phagocytic and fungicidal capacities by post-exercise physiological concentrations of Hsp72. Human peripheral blood neutrophils were incubated with fluorescein isothiocyanate-conjugated Hsp72, and were analyzed by immunofluorescence microscopy and flow cytometry. Both methods revealed an interaction of Hsp72 with neutrophils. In addition, when neutrophils were pre-incubated with an anti-TLR-2 antibody this interaction was clearly decreased. Post-exercise circulating concentration of Hsp72 (8.6 ng/ml) stimulated the phagocytic and fungicidal capacities of neutrophils and this effect could be also blocked using an antibody against TLR-2. Phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated kinase (ERK) and the nuclear transcription factor kappa beta (NF-kappabeta) were found to be involved in the signaling process, confirming the participation of TLR-2 in the stimulation of neutrophil function by Hsp72. In conclusion, TLR-2 is involved at least in part, in the stimulation of neutrophil phagocytic and fungicidal capacities induced by post-exercise physiological concentrations of Hsp72.
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Giraldo E, Martin-Cordero L, Hinchado MD, Garcia JJ, Ortega E. Role of phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated kinase (ERK) and nuclear transcription factor kappa beta (NF-k beta) on neutrophil phagocytic process of Candida albicans. Mol Cell Biochem 2009; 333:115-20. [PMID: 19609651 DOI: 10.1007/s11010-009-0211-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 07/06/2009] [Indexed: 01/21/2023]
Abstract
In humans, Candida albicans is the microorganism most frequently associated with fungal infections. Alterations in the balance between the host and this commensal pathogen, turns into a parasitic relationship which results in the development of invasive infections. Neutrophils via chemotaxis, phagocytosis, and microbicide capacity can eradicate this pathogen. Taken together, the aim of this work was to study the possible role of phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated kinase (ERK) and the nuclear transcription factor kappa beta (NF-k beta) on the phagocytic process of neutrophils. The chemotactic capacity of neutrophils and their ability to phagocytose and to destroy C. albicans in absence and presence of 1, 10, or 100 microM of wortmannin (a PI3K inhibitor); 10, 25, or 50 microM of Bay 11-7082 (a NF-k beta inhibitor) or 1, 5 or 10 microM of PD 98,059 (an ERK inhibitor) were determined. Our results show that fMLP-induced chemotaxis needs the participation of PI3K and NF-k beta. In contrast, ERK seems not to be involved. On the other hand, the inhibition of NF-kappa beta and ERK decreased neutrophil phagocytosis and microbicide capacity against C. albicans. However, both the phagocytic and candicide capacities were PI3K independent.
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Affiliation(s)
- E Giraldo
- Department of Physiology, Faculty of Sciences, University of Extremadura, 06071, Badajoz, Spain
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Ortega E, Hinchado MD, Martín-Cordero L, Asea A. The effect of stress-inducible extracellular Hsp72 on human neutrophil chemotaxis: a role during acute intense exercise. Stress 2009; 12:240-9. [PMID: 18850491 DOI: 10.1080/10253890802309853] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
We studied the physiological role of the 72 kDa extracellular heat shock protein (Hsp72, a stress-inducible protein) in modulating neutrophil chemotaxis during a single bout of intense exercise performed by sedentary women, together with various cell mechanisms potentially involved in the modulation. For each volunteer, we evaluated neutrophil chemotaxis and serum Hsp72 concentration before and immediately after a single bout of exercise (1 h on a cycle ergometer at 70% VO(2) max), and 24 h later. Both parameters were found to be stimulated by the exercise, and had returned to basal values 24 h later. In vitro, there was a dose-dependent increase in chemotaxis when neutrophils were incubated both with physiological Hsp72 concentrations and with a 100 x greater concentration. The chemotaxis was greater when the neutrophils were incubated with the post-exercise Hsp72 concentration than with the basal concentration, suggesting a physiological role for this protein in the context of the stimulation of neutrophil chemotaxis by intense exercise. The 100 x Hsp72 concentration stimulated chemotaxis even more strongly. In addition, Hsp72 was found to have chemoattractant and chemokinetic effects on the neutrophils at physiological concentrations, with these effects being significantly greater with the post-exercise than with the basal Hsp72 concentration. The Hsp72-induced stimulation of neutrophil chemotaxis disappeared when the toll-like receptor 2 (TLR-2) was blocked, and phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated kinase (ERK), and nuclear transcription factor kappa B (NF-kappaB) were also found to be involved in the signaling process. No changes were observed, however, in neutrophil intracellular calcium levels in response to Hsp72. In conclusion, physiological concentrations of the stress protein Hsp72 stimulate human neutrophil chemotaxis through TLR-2 with its cofactor CD14, involving ERK, NF-kappaB, and PI3K, but not iCa(2 + ), as intracellular messengers. In addition, Hsp72 seems to participate in the stimulation of chemotaxis induced by a single bout of intense exercise performed by sedentary women.
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Affiliation(s)
- Eduardo Ortega
- Department of Physiology, Faculty of Sciences, University of Extremadura, Badajoz, Spain.
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He H, Genovese KJ, Nisbet DJ, Kogut MH. Phospholipase C, phosphatidylinositol 3-kinase, and intracellular [Ca(2+)] mediate the activation of chicken HD11 macrophage cells by CpG oligodeoxynucleotide. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2008; 32:1111-8. [PMID: 18403015 DOI: 10.1016/j.dci.2008.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 02/25/2008] [Accepted: 02/27/2008] [Indexed: 05/22/2023]
Abstract
The activation of phospholipases is one of the earliest key events in receptor-mediated cellular responses to a number of extracellular signaling molecules. Oligodeoxynucleotides containing CpG motifs (CpG ODN) mimic microbial DNA and are immunostimulatory to most vertebrate species. In the present study, we used the production of nitric oxide (NO) as an indicator to evaluate the involvement of the signaling cascades of phospholipases and phosphatidylinositol 3-kinase (PI3K) in the activation of chicken HD11 macrophage cells by CpG ODN. Using selective inhibitors, we have identified the involvement of phosphatidylinositol (PI)-phospholipase C (PI-PLC), but not phosphatidylcholine (PC)-phospholipase C (PC-PLC) and PC-phospholipase D (PC-PLD), in CpG ODN-induced NO production in HD11 cells. Preincubation with PI-PLC selective inhibitors (U-73122) completely abrogated CpG ODN-induced NO production in HD11 cells, whereas PC-PLC inhibitor (D609) and PC-PLD inhibitor (n-butanol) had no inhibitory effects. Additionally, inhibition of PI3K and protein kinase C (PKC) with selective inhibitors and chelation of intracellular [Ca(2+)] also significantly attenuated NO production in CpG ODN-activated HD11 cells. Our results demonstrate that PI-PLC, PI3 K, PKC, and intracellular [Ca(2+)] are important components of the CpG ODN-induced signaling pathway that leads to the production of NO in avian macrophage cells.
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Affiliation(s)
- Haiqi He
- Southern Plain Agricultural Research Center, USDA-ARS, 2881 F&B Road, College Station, TX 77845, USA.
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He H, Genovese KJ, Nisbet DJ, Kogut MH. Involvement of phosphatidylinositol-phospholipase C in immune response to Salmonella lipopolysacharide in chicken macrophage cells (HD11). Int Immunopharmacol 2006; 6:1780-7. [PMID: 17052668 DOI: 10.1016/j.intimp.2006.07.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 07/10/2006] [Accepted: 07/13/2006] [Indexed: 11/17/2022]
Abstract
The activation of phospholipases is one of the earliest key events in receptor-mediated cellular responses to a number of extracellular signaling molecules. Lipopolysaccharide (LPS) is a principle component of the outer membrane of Gram-negative bacteria and a prime target for recognition by the innate immune system. In the present study, we evaluated the role of specific phospholipase in the activation of a chicken macrophage cell line HD11 by LPS. Activation of HD11 cells by LPS results in induction of nitric oxide (NO). Using selective inhibitors, we have identified that phosphatidylinositol (PI)-phospholipase C (PI-PLC), but not phosphatidylcholine (PC)-phospholipase C (PC-PLC) nor PC-phospholipase D (PC-PLD), was required for LPS-induced NO production. Preincubation with PI-PLC selective inhibitors (U-73122 and ET-18-OCH3) abrogated LPS-induced NO production in HD11 cells, whereas PC-PLC inhibitor (D609), phosphatide phosphohydrolase inhibitor (propranolol), and PC-PLD inhibitor (n-butanol) had no inhibitory effects. We also showed that inhibition of protein kinase C (PKC) by selective inhibitors Ro 31-8220 and calphostin C and chelating intracellular Ca2+ by BAPTA-AM significantly reduced NO production in LPS-stimulated HD11 cells. Our results demonstrate that PI-PLC plays a critical role, most likely through activation of PKC pathway, in TLR4 mediated immune responses of avian macrophage cells to LPS.
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Affiliation(s)
- Haiqi He
- Southern Plain Agricultural Research Center, USDA-ARS, College Station, TX 77845, USA.
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Werling D, Coffey TJ. Pattern recognition receptors in companion and farm animals - the key to unlocking the door to animal disease? Vet J 2006; 174:240-51. [PMID: 17137812 PMCID: PMC7110490 DOI: 10.1016/j.tvjl.2006.10.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2006] [Revised: 08/07/2006] [Accepted: 10/04/2006] [Indexed: 01/27/2023]
Abstract
The innate immune system is essential for host defence and is responsible for early detection of potentially pathogenic microorganisms. Upon recognition of microbes by innate immune cells, such as macrophages and dendritic cells, diverse signalling pathways are activated that combine to define inflammatory responses that direct sterilisation of the threat and/or orchestrate development of the adaptive immune response. Innate immune signalling must be carefully controlled and regulation comes in part from interactions between activating and inhibiting signalling receptors. In recent years, an increasing number of pattern recognition receptors (PRRs), including C-type lectin receptors and Toll-like receptors (TLRs), has been described that participate in innate recognition of microbes, especially through the so called pathogen-associated molecular patterns (PAMPs). Recent studies demonstrate strong interactions between signalling through these receptors. Whereas useful models to study these receptors in great detail in the murine and human system are now emerging, relatively little is known regarding these receptors in companion and farm animals. In this review, current knowledge regarding these receptors in species of veterinary relevance is summarised.
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Affiliation(s)
- Dirk Werling
- Royal Veterinary College, Department of Pathology and Infectious Diseases, Hawkshead Lane, Hatfield AL9 7TA, UK.
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Nitto T, Dyer KD, Czapiga M, Rosenberg HF. Evolution and Function of Leukocyte RNase A Ribonucleases of the Avian Species, Gallus gallus. J Biol Chem 2006; 281:25622-34. [PMID: 16803891 DOI: 10.1074/jbc.m604313200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
In this study, we explore the evolution and function of two closely related RNase A ribonucleases from the chicken, Gallus gallus. Separated by approximately 10 kb on chromosome 6, the coding sequences of RNases A-1 and A-2 are diverging under positive selection pressure (dN > dS) but remain similar to one another (81% amino acid identity) and to the mammalian angiogenins. Immunoreactive RNases A-1 and A-2 (both approximately 16 kDa) were detected in peripheral blood granulocytes and bone marrow. Recombinant proteins are ribonucleolytically active (kcat = 2.6 and 0.056 s(-1), respectively), and surprisingly, both interact with human placental ribonuclease inhibitor. RNase A-2, the more cationic (pI 11.0), is both angiogenic and bactericidal; RNase A-1 (pI 10.2) has neither activity. We demonstrated via point mutation of the catalytic His110 that ablation of ribonuclease activity has no impact on the bactericidal activity of RNase A-2. We determined that the divergent domains II (amino acids 71-76) and III (amino acids 89-104) of RNase A-2 are both important for bactericidal activity. Furthermore, we demonstrated that these cationic domains can function as independent bactericidal peptides without the tertiary structure imposed by the RNase A backbone. These results suggest that ribonucleolytic activity may not be a crucial constraint limiting the ongoing evolution of this gene family and that the ribonuclease backbone may be merely serving as a scaffold to support the evolution of novel, nonribonucleolytic proteins.
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Affiliation(s)
- Takeaki Nitto
- Laboratory of Allergic Diseases and Research Technologies Branch, NIAID, National Institutes of Health, Bethesda, Maryland 20892, USA
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Oda K, Kitano H. A comprehensive map of the toll-like receptor signaling network. Mol Syst Biol 2006; 2:2006.0015. [PMID: 16738560 PMCID: PMC1681489 DOI: 10.1038/msb4100057] [Citation(s) in RCA: 242] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Accepted: 02/23/2006] [Indexed: 12/18/2022] Open
Abstract
Recognition of pathogen-associated molecular signatures is critically important in proper activation of the immune system. The toll-like receptor (TLR) signaling network is responsible for innate immune response. In mammalians, there are 11 TLRs that recognize a variety of ligands from pathogens to trigger immunological responses. In this paper, we present a comprehensive map of TLRs and interleukin 1 receptor signaling networks based on papers published so far. The map illustrates the possible existence of a main network subsystem that has a bow-tie structure in which myeloid differentiation primary response gene 88 (MyD88) is a nonredundant core element, two collateral subsystems with small GTPase and phosphatidylinositol signaling, and MyD88-independent pathway. There is extensive crosstalk between the main bow-tie network and subsystems, as well as feedback and feedforward controls. One obvious feature of this network is the fragility against removal of the nonredundant core element, which is MyD88, and involvement of collateral subsystems for generating different reactions and gene expressions for different stimuli.
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Affiliation(s)
- Kanae Oda
- The Systems Biology Institute, Tokyo, Japan
- Department of Fundamental Science and Technology, Keio University, Tokyo, Japan
| | - Hiroaki Kitano
- The Systems Biology Institute, Tokyo, Japan
- Department of Fundamental Science and Technology, Keio University, Tokyo, Japan
- Sony Computer Science Laboratories Inc., Tokyo, Japan
- The Systems Biology Institute, Suite 6A, M31 6-31-15 Jingumae, Shibuya, Tokyo 150-0001, Japan. Tel.: +81 3 5468 1661; Fax: +81 3 5468 1664; E-mail:
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He H, Lowry VK, Swaggerty CL, Ferro PJ, Kogut MH. In vitro activation of chicken leukocytes and in vivo protection against Salmonella enteritidis organ invasion and peritoneal S. enteritidis infection-induced mortality in neonatal chickens by immunostimulatory CpG oligodeoxynucleotide. ACTA ACUST UNITED AC 2005; 43:81-9. [PMID: 15607640 DOI: 10.1016/j.femsim.2004.07.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Revised: 07/22/2004] [Accepted: 07/23/2004] [Indexed: 11/17/2022]
Abstract
Unmethylated CpG oligodinucleotides (CpG-ODN) flanked by specific bases found in bacterial DNA are known to stimulate innate immune responses. In this study, synthetic CpG-ODNs were evaluated for their in vitro stimulation of leukocyte and in vivo protection against Salmonella enteritidis (SE) in neonatal chickens. Our studies showed that CpG-ODN stimulated bactericidal activities, releasing granules (degranulation) and generating reactive oxygen species (oxidative burst), in chicken heterophils and up regulated nitric oxide production in chicken peripheral blood monocytes. When day-old chickens were given (i.p.) synthetic CpG-ODNs followed by oral challenge of SE, a significant reduction (p<0.05) of organ invasion by SE was observed in chickens pretreated with CpG-ODN containing the immunostimulatory GTCGTT motif. This CpG-OND also significantly reduced mortality of chickens with acute peritoneal infection of SE. Our study provides evidence that immunostimulatory CpG-ODN stimulated innate immune activities and enhanced the resistance to infectious pathogens in neonatal chickens.
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Affiliation(s)
- Haiqi He
- Southern Plains Agricultural Research Center, USDA-ARS, 2881 F and B Road, College Station, TX 77845, USA.
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Bliss TW, Dohms JE, Emara MG, Keeler CL. Gene expression profiling of avian macrophage activation. Vet Immunol Immunopathol 2005; 105:289-99. [PMID: 15808307 DOI: 10.1016/j.vetimm.2005.02.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Through the process of phagocytosis, the macrophage is responsible for the clearance and destruction of both intracellular and extracellular pathogens. When stimulated, macrophages undergo a process of activation involving an increase in size and motility, enhanced phagocytic, bactericidal, and tumoricidal activity, and up-regulation of several cell-surface markers. One well characterized method of mammalian macrophage activation involves the Toll-like receptor (TLR) pathway. TLRs are surface molecules that function as direct receptors for microbial components. Binding of ligand to TLRs results in activation of transcription factors that regulate genes involved in microbial killing, apoptosis, and antigen recognition, as well as pro- and anti-inflammatory cytokines and chemokines. We have constructed a 4906-element (14,718 spot) avian macrophage-specific cDNA microarray (AMM). The AMM contains 16 of the approximately 44 genes identified within the mammalian TLR pathway. This array was used to examine the transcriptional response of avian macrophages to Gram-negative bacteria and their cell wall components and to evaluate the contribution of the avian TLR pathway to that response. Of the elements on the AMM, 981 (20%) exhibited significant (greater than two-fold, p < 0.01) changes in expression during phagocytosis of Escherichia coli and 243 (5%) exhibited significant expression changes during exposure to lipopolysaccharide (LPS). A unique set of overlapping elements (154), were observed to exhibit significant changes in expression for both phagocytosis and LPS stimulation, representing a set of core response elements. Of these elements, 63% were commonly induced, while 32% were commonly repressed. Both LPS and bacteria were found to induce NFkappabeta and several end products of the TLR pathway.
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Affiliation(s)
- Travis W Bliss
- Department of Animal and Food Sciences, College of Agriculture and Natural Resources, University of Delaware, Newark, DE 19716-2150, USA
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Iqbal M, Philbin VJ, Withanage GSK, Wigley P, Beal RK, Goodchild MJ, Barrow P, McConnell I, Maskell DJ, Young J, Bumstead N, Boyd Y, Smith AL. Identification and functional characterization of chicken toll-like receptor 5 reveals a fundamental role in the biology of infection with Salmonella enterica serovar typhimurium. Infect Immun 2005; 73:2344-50. [PMID: 15784580 PMCID: PMC1087448 DOI: 10.1128/iai.73.4.2344-2350.2005] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toll-like receptors (TLRs) are a major component of the pattern recognition receptor repertoire that detect invading microorganisms and direct the vertebrate immune system to eliminate infection. In chickens, the differential biology of Salmonella serovars (systemic versus gut-restricted localization) correlates with the presence or absence of flagella, a known TLR5 agonist. Chicken TLR5 (chTLR5) exhibits conserved sequence and structural similarity with mammalian TLR5 and is expressed in tissues and cell populations of immunological and stromal origin. Exposure of chTLR5+ cells to flagellin induced elevated levels of chicken interleukin-1beta (chIL-1beta) but little upregulation of chIL-6 mRNA. Consistent with the flagellin-TLR5 hypothesis, an aflagellar Salmonella enterica serovar Typhimurium fliM mutant exhibited an enhanced ability to establish systemic infection. During the early stages of infection, the fliM mutant induced less IL-1beta mRNA and polymorphonuclear cell infiltration of the gut. Collectively, the data represent the identification and functional characterization of a nonmammalian TLR5 and indicate a role in restricting the entry of flagellated Salmonella into systemic sites of the chicken.
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Affiliation(s)
- Muhammad Iqbal
- Division of Immunology and Pathology, Institute for Animal Health, Compton, Newbury, Berkshire RG20 7NN, United Kingdom
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