The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Michael H. Kogut - One of the best experts on this subject based on the ideXlab platform.
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The avian heterophil.
Developmental and comparative immunology, 2013Co-Authors: Kenneth J Genovese, Christina L Swaggerty, Michael H. KogutAbstract: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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gene expression analysis of toll like receptor pathways in heterophils from genetic chicken lines that differ in their susceptibility to salmonella enteritidis
Frontiers in Genetics, 2012Co-Authors: Michael H. Kogut, Christina L Swaggerty, Hsini Chiang, Igal Y Pevzner, Huaijun ZhouAbstract:Previously conducted studies using two chicken lines (A and B) show that line A birds have increased resistance to a number of bacterial and protozoan challenges and that het- erophils isolated from line A birds are functionally more responsive. Furthermore, when stimulated withToll-like receptor (TLR) agonists, heterophils from line A expressed a totally different cytokine and chemokine mRNA expression pattern than heterophils from line B. A large-scale gene expression profile using an Agilent 44K microarray on heterophils isolated from line A and line B also revealed significantly differential expression in many immune-related genes following Salmonella enteritidis (SE) stimulation, which included genes involved in the TLR pathway. Therefore, we hypothesize the differences between the lines result from distinctive TLR pathway signaling cascades that mediate heterophil function and, thus, innate immune responsiveness to SE. Using quantitative RT-PCR on mRNA from heterophils isolated from control and SE-stimulated heterophils of each line, we profiled the expression of all chicken homologous genes identified in a reference TLR pathway. Several differentially expressed genes found were involved in the TLR-induced My88-dependent pathway, showing higher gene expression in line A than line B heterophils following SE stimulation. These genes included the TLR genes TLR4, TLR15, TLR21, MD-2, the adaptor proteins Toll-interleukin 1 receptor domain-containing adaptor protein (TIRAP ), Tumor necrosis factor-receptor associated factor 3 (TRAF3), the IkB kinases transforming growth factor-b-activating kinase 1 (TAK1), IKK+ and IKKa, the transcription factors NFkB2 and interferon regulatory factor 7, phosphatidylinositol-3 kinase (PI-3K ), and the mitogen- activated protein kinase p38. These results indicate that higher expression of TLR signaling activation of both MyD88-dependent and TRIF-dependent pathways are more beneficial to avian heterophil-mediated innate immunity and a complicated regulation of downstream adaptors is involved in stronger induction of a TLR-mediated innate response in the resis- tant line A.These findings identify new targets for genetic selection of chickens to increase resistance to bacterial infections.
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bacterial toll like receptor agonists induce sequential nf κb mediated leukotriene b4 and prostaglandin e2 production in chicken heterophils
Veterinary Immunology and Immunopathology, 2012Co-Authors: Michael H. Kogut, Kenneth J GenoveseAbstract:Studies of the response of the primary avian polymorphonuclear leukocyte, the heterophil, to microbe associated molecular patterns (MAMPs) through toll-like receptors (TLR) has concentrated on the activation of the respiratory burst, release of intracellular granules, and the induction of cytokine and chemokine expression. Virtually no studies have been described on the role of lipid mediators, leukotrienes and prostaglandins, as effectors of the avian inflammatory response. We have previously shown that flagellin (FLG), the bacterial lipoprotein mimic palmitoly-3-cysteine-serine-lysine-4 (PAM), and unmethylated CpG motifs of bacteria DNA (CpG) are all potent activators of the avian innate immune system. In the present studies, we hypothesized that FLG, PAM, and CpG are also capable of eliciting the production of these lipid mediators of inflammation by avian heterophils. Compared to non-stimulated control heterophils, all three TLR agonists were potent inducers (3-5-fold increase) of a rapid production (30 min) of leukotriene B(4) (LTB(4)) followed by a later release (60-120 min) of prostaglandin (PGE(2)) by the heterophils. LTB(4) and PGE(2) production were derived from lipoxygenase-5 (5-LO) and cyclooxygenase-2 (COX-2) enzymatic activities, respectively, as the selective 5-LO (caffeic acid) and COX-2 (NS-398) inhibitors eliminated LTB(4) and PGE(2) production from the MAMP-stimulated heterophils. These results demonstrate that both the lipoxygenase and cycloxygenase pathways are operational in avian heterophils in response to bacterial MAMPs. Treatment of heterophils with either FLG, PAM, or CpG also induced a significant increase in DNA binding by NF-κB family members' p50, c-Rel, and RelB. Additionally, the production of LTB(4) and PGE(2) were inhibited following treatment of heterophils with the specific pharmacologic inhibitor of NF-κB (Bay 11-7086), thus suggesting that TLR pathway activation of NF-κB controls LTB(4) and PGE(2) production. This the first report of the production of lipid mediators of inflammation by avian heterophils in response to PAMPs. Since FLG, lipoproteins, and bacterial CpG DNA are abundant during bacterial infections, these data support their role in the inflammatory response mediated by avian heterophils.
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Differential mRNA expression of the avian-specific toll-like receptor 15 between heterophils from Salmonella-susceptible and -resistant chickens
Immunogenetics, 2009Co-Authors: Jessica R. Nerren, Kenneth J Genovese, Christina L Swaggerty, Kathryn M. Mackinnon, Igal Pevzner, Michael H. KogutAbstract:Pattern recognition receptors (PRRs) are essential for recognition of conserved molecular constituents found on infectious microbes. Toll-like receptors (TLRs) are a critical component of the PRR repertoire and are coupled to downstream production of cytokines, chemokines, and antimicrobial peptides by TLR adaptor proteins. Our laboratory previously demonstrated a role for TLR function in the differential innate response of two lines of chickens to bacterial infections. The aim of the present study was to elucidate the role of TLRs in the differential innate responsiveness by measuring differences between lines A (resistant) and B (susceptible) in heterophil mRNA expression of selected TLRs (TLRs 4, 5, and 15) and TLR adaptor proteins (MyD88, TRIF, and TIRAP) in response to stimulation with Salmonella enterica serovar Enteritidis (SE). Although heterophils from both lines had significantly increased expression of TLR 15 mRNA in response to stimulation with SE, heterophils from chickens resistant to infection with SE had significantly greater levels of TLR 15 mRNA expression prior to and following stimulation with SE than heterophils from chickens susceptible to infection with SE. No significant differences were noted between lines in nonstimulated levels of TIRAP, but upon SE stimulation, line A birds had higher levels of expression than B birds. No significant differences were found in heterophils between lines for mRNA expression of TLRs 4 and 5 nor MyD88 and TRIF. These data indicate that differences in the gene expression of TLR 15 by heterophils likely accounts for some of the observed differences between the lines in their susceptibility to infection.
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flagellin and lipopolysaccharide up regulation of il 6 and cxcli2 gene expression in chicken heterophils is mediated by erk1 2 dependent activation of ap 1 and nf κb signaling pathways
Innate Immunity, 2008Co-Authors: Michael H. Kogut, Kenneth J Genovese, Peter K KaiserAbstract:The Toll-like receptor agonists, flagellin (FLG) and lipopolysaccharide (LPS), stimulate chicken heterophils to induce the expression and secretion of pro-inflammatory cytokines by a mechanism involving the triggering of differential MEK-ERK signaling cascades. However, the translocation and activation of transcription factors potentially involved in the control of cytokine gene expression remains unknown. Herein, we examined the effects of FLG and LPS on the activation of the transcription factors NF-κB and AP-1 and their role in regulating heterophil activation leading to cytokine gene expression. Treatment of heterophils with either FLG or LPS induced a significant increase in DNA binding by the NF-κB family members p50, c-Rel, and RelB. Likewise, FLG and LPS induced a significant increase in DNA binding by the AP-1 family members c-Jun and JunD. The activation of both NF-κB and AP-1 was inhibited following treatment of heterophils with specific inhibitors of ERK1/2 (U0126 and PD098059), NF-κB (Bay 11-...
Peter K Kaiser - One of the best experts on this subject based on the ideXlab platform.
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cytokine and chemokine gene expression profiles in heterophils from chickens treated with corticosterone
Stress, 2010Co-Authors: Shaniko Shini, Agim Shini, Peter K KaiserAbstract:In chickens, corticosterone is the end-product of stress. However, the nature of the immune response to elevated plasma corticosterone concentrations at the molecular level has not yet been characterised. We recently demonstrated that exposure to corticosterone in drinking water for 1 week significantly upregulates mRNA expression levels for the pro-inflammatory interleukins (IL)-1β, IL-6, IL-18 and the pro-inflammatory chemokine CCLi2 in chicken lymphocytes, particularly 3 h after the treatment started. In the present study, we investigated cytokine and chemokine mRNA expression levels in circulating heterophils of chickens, and show that at 3 h post initial treatment with corticosterone in drinking water (20 mg/1L) the mRNA expression levels for IL-1β, IL-6, IL-10, IL-12α and IL-18 are upregulated. The mRNA expression levels for IL-6, IL-10 and IL-18 correlate with plasma corticosterone concentration and total heterophil counts. Corticosterone downregulated the expression levels of all pro-inflammatory cytokines at 24 h and 1 week post-treatments. Repeated treatment with corticosterone upregulated mRNA expression levels of transforming growth factor-β4 and the chemokine CCL16. These data indicate that cytokine and chemokine gene expression signatures in chicken heterophils can be altered during stress and therefore could be used as an indicator of stress. Copyright © 2010 Informa Plc. All rights reserved.
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flagellin and lipopolysaccharide up regulation of il 6 and cxcli2 gene expression in chicken heterophils is mediated by erk1 2 dependent activation of ap 1 and nf κb signaling pathways
Innate Immunity, 2008Co-Authors: Michael H. Kogut, Kenneth J Genovese, Peter K KaiserAbstract:The Toll-like receptor agonists, flagellin (FLG) and lipopolysaccharide (LPS), stimulate chicken heterophils to induce the expression and secretion of pro-inflammatory cytokines by a mechanism involving the triggering of differential MEK-ERK signaling cascades. However, the translocation and activation of transcription factors potentially involved in the control of cytokine gene expression remains unknown. Herein, we examined the effects of FLG and LPS on the activation of the transcription factors NF-κB and AP-1 and their role in regulating heterophil activation leading to cytokine gene expression. Treatment of heterophils with either FLG or LPS induced a significant increase in DNA binding by the NF-κB family members p50, c-Rel, and RelB. Likewise, FLG and LPS induced a significant increase in DNA binding by the AP-1 family members c-Jun and JunD. The activation of both NF-κB and AP-1 was inhibited following treatment of heterophils with specific inhibitors of ERK1/2 (U0126 and PD098059), NF-κB (Bay 11-...
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toll like receptor agonists stimulate differential functional activation and cytokine and chemokine gene expression in heterophils isolated from chickens with differential innate responses
Microbes and Infection, 2006Co-Authors: Michael H. Kogut, Christina L Swaggerty, I Y Pevzner, Peter K KaiserAbstract:Heterophils isolated from distinct broilers (lines A and B) differ in function and cytokine gene expression profiles. Nothing is known about Toll-like receptor (TLR) expression nor functional activation and cytokine/chemokine gene expression of line A and B heterophils when stimulated with TLR agonists. We found that line A and B heterophils express the same range of TLRs. All the bacterial TLR agonists, peptidoglycan, the synthetic lipoprotein Pam3CSK4, ultra-pure lipopolysaccharide, and flagellin all induced significantly greater functional activation of heterophils from line A compared to B. Only stimulation with the guanosine analog, loxoribine, (LOX) induced a significantly greater functional response in B over A. Additionally, all heterophils from line A stimulated with the bacterial TLR agonists had dramatic upregulation of pro-inflammatory cytokine and chemokine mRNA expression, whereas heterophils from line B had little or no upregulation of these genes. However, stimulation of all heterophils from line B with the bacterial TLR agonists and LOX induced a significant upregulation of IFN-α, with little transcription of this cytokine gene in line A heterophils. These findings suggest that the difference in heterophil functional efficiency between these parent lines is due to recognition of pathogens and activation of signaling pathways that induce innate cytokine and chemokine responses.
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Heterophil cytokine mRNA profiles from genetically distinct lines of chickens with differential heterophil-mediated innate immune responses
Avian pathology : journal of the W.V.P.A, 2006Co-Authors: Christina L Swaggerty, I Y Pevzner, Lisa Rothwell, Peter K Kaiser, Michael H. KogutAbstract:Previously we demonstrated that increased in-vitro heterophil function translates to increased in-vivo resistance to Salmonella enteritidis infections in broilers (line A > B). Heterophils produce cytokines and modulate acute protection against Salmonella in neonatal poultry. We hypothesized that heterophils from S. enteritidis-resistant chickens produce an up-regulated pro-inflammatory cytokine/chemokine response compared with S. enteritidis-susceptible chickens. In this study, heterophils were isolated 1, 14, and 28 days post-hatch, treated with RPMI or phagocytic agonists, and the cytokine/chemokine mRNA expression assessed using quantitative real-time reverse transcriptase-polymerase chain reaction. At all time-points, heterophils from S. enteritidis-resistant chickens (line A) had higher levels of pro-inflammatory cytokine/chemokine mRNA expression upon stimulation compared with heterophils from S. enteritidis-susceptible chickens (line B). Furthermore, heterophils from line A chickens had decreased mRNA expression of transforming growth factor-beta4, an anti-inflammatory cytokine, compared with line B. These data indicate a relationship between cytokine/chemokine mRNA expression by heterophils and determining overall immune competence. Therefore, heterophil functional efficiency, accompanied by evaluating cytokine/chemokines produced by heterophils, may be useful biomarkers for breeders to consider when developing new immunocompetent lines.
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Expression and function of Toll-like receptors in chicken heterophils.
Developmental and comparative immunology, 2005Co-Authors: Michael H. Kogut, Peter K Kaiser, Muhammad Iqbal, Victoria J. Philbin, Adrian SmithAbstract:The heterophil is the major polymorphonuclear cell in birds with a functional capacity akin to that of the mammalian neutrophil. Herein, we demonstrate that heterophils constitutively express TLR1/6/10, TLR2 type 1, TLR2 type 2, TLR3, TLR4, TLR5, and TLR7 mRNA. Furthermore, TLR agonists, including flagellin (from Salmonella typhimurium, FGN), peptidoglycan (from Staphylococcus aureus, PGN), ultra-pure lipopolysaccharide (from Salmonella minnesota, LPS), the synthetic double stranded RNA analog [poly(I:C)], and the guanosine analog, loxoribine (LOX) directly induced both an oxidative burst and a degranulation response. Interestingly, the synthetic bacterial lipoprotein Pam3CSK4 (palmitoyl-3-cysteine-serine-lysine-4, PAM) induced degranulation, but no oxidative burst. The bacterial TLR agonists (PAM, PGN, LPS, and FGN) all induced an up-regulation of expression of mRNA of the pro-inflammatory cytokines IL-1beta, IL-6, and IL-8; whereas both poly(I:C) and LOX induced a down-regulation of these cytokine mRNAs. Stimulation of heterophils with each specific TLR agonist led to a differential increase in the phosphorylation of both p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase 1/2 (ERK 1/2) activation, but not the phosphorylation of c-Jun NH2-terminal kinase (JNK). The broad TLR expression profile in heterophils reflects their principal role as first line effector cells in avian host defense against bacterial, viral, fungal, and parasitic infections. The results demonstrate the differential involvement of TLR-induced signals in the stimulation of transduction pathways that regulate the oxygen-dependent and -independent antimicrobial defense mechanisms of avian heterophils.
Makoto Shimoyama - One of the best experts on this subject based on the ideXlab platform.
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Exocytosis of arginine-specific ADP-ribosyltransferase and p33 induced by A23187 and calcium or serum-opsonized zymosan in chicken polymorphonuclear leukocytes.
Journal of biochemistry, 1996Co-Authors: Masaharu Terashima, Mikako Tsuchiya, Muhammad Badruzzaman, Makoto ShimoyamaAbstract:Exocytosis is a common phenomenon in neutrophil functions. We earlier reported the co-localization of arginine-specific ADP-ribosyltransferase [EC 2.4.2.31] and its target protein p33 (mim-1 protein) in cytoplasmic granules in chicken polymorphonuclear leukocytes (so-called heterophils) [Mishima, K., Terashima, M., Obara, S., Yamada, K., Imai, K., and Shimoyama, M. (1991) J. Biochem. 110, 388-394]. In the present study, we obtained evidence that the transferase and p33 were released into the extracellular space by the stimulus of calcium ionophore A23187 or serum-opsonized zymosan, but scarcely by phorbol myristate acetate (PMA) or N-formyl-Met-Leu-Phe (fMLP), thereby indicating the co-localization of the transferase and p33 in the azurophilic granules, and not in specific granules. [32P]ADP-ribosylation of p33 occurred in the extracellular space, induced by the stimulus of A23187 or opsonized zymosan in the presence of [32P]NAD. Our findings are interpreted to mean that heterophil transferase and p33 may be involved in neutrophil functions during processes of inflammation.
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Target protein for eucaryotic arginine-specific ADP-ribosyltransferase
Molecular and Cellular Biochemistry, 1994Co-Authors: Mikako Tsuchiya, Makoto ShimoyamaAbstract:Among ADP-ribosyltransferases reported in eucaryotes, arginine-specific transferases from turkey erythrocytes, chicken heterophils and rabbit skeletal muscle have been purified and extensively studied. They were reported to modify a number of proteins in vitro . ADP-ribosylation of Ha- ras -p21 and transducin by the turkey erythrocyte transferase inhibits their GTPase and GTP-binding activities. Chicken heterophil enzyme modifies several substrate proteins for protein kinases and decreases the phosphate-acceptor activity. Rabbit skeletal muscle Ca^2+-ATPase is inhibited by ADP-ribosylation catalyzed by the muscle transferase. Three transferases all ADP-ribosylate small molecular weight guanidino compounds such as arginine, arginine methylester and agmatine and poly-L-arginine and nuclear histones. However, the observation that muscle transferase did not ADP-ribosylate casein or actin, both of which can be modified by the heterophil transferase under the same conditions indicates that substrate specificity of these two enzymes are different. Substrate-dependent effects were observed with polyions of nucleotides such that polyanions stimulate the ADP-ribosylation of possible target protein, p33 by chicken heterophil transferase but has no effect on the modification of casein by the same enzyme.
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Target protein for eucaryotic arginine-specific ADP-ribosyltransferase
Molecular and Cellular Biochemistry, 1994Co-Authors: Mikako Tsuchiya, Makoto ShimoyamaAbstract:Among ADP-ribosyltransferases reported in eucaryotes, arginine-specific transferases from turkey erythrocytes, chicken heterophils and rabbit skeletal muscle have been purified and extensively studied. They were reported to modify a number of proteins in vitro. ADP-ribosylation of Ha-ras-p21 and transducin by the turkey erythrocyte transferase inhibits their GTPase and GTP-binding activities. Chicken heterophil enzyme modifies several substrate proteins for protein kinases and decreases the phosphate-acceptor activity. Rabbit skeletal muscle Ca2+-ATPase is inhibited by ADP-ribosylation catalyzed by the muscle transferase. Three transferases all ADP-ribosylate small molecular weight guanidino compounds such as arginine, arginine methylester and agmatine and poly-L-arginine and nuclear histones. However, the observation that muscle transferase did not ADP-ribosylate casein or actin, both of which can be modified by the heterophil transferase under the same conditions indicates that substrate specificity of these two enzymes are different. Substrate-dependent effects were observed with polyions of nucleotides such that polyanions stimulate the ADP-ribosylation of possible target protein, p33 by chicken heterophil transferase but has no effect on the modification of casein by the same enzyme. (Mol Cell Biochem 138: 113–118, 1994)
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adp ribosylation of actins by arginine specific adp ribosyltransferase purified from chicken heterophils
FEBS Journal, 1992Co-Authors: Masaharu Terashima, Koichi Mishima, Kazuo Yamada, Mikako Tsuchiya, Tadao Wakutani, Makoto ShimoyamaAbstract:We reported the purification and characterization of an arginine-specific ADP-ribosyltransferase and acceptor protein p33 in granules of chicken peripheral polymorphonuclear leukocytes (heterophils) [Mishima, K., Terashima, M., Obara, S., Yamada, K., Imai, K. & Shimoyama, M. (1991) J. Biochem. (Tokyo) 110, 388–394]. In the present study, we obtained evidence that chicken non-muscle β/γ-actin, skeletal muscle α-actin and smooth-muscle γ-actin were ADP ribosylated by the heterophil ADP-ribosyltransferase. The stoichiometry of ADP–ribose incorporation into these actins was 1.2 mol, 1.0 mol and 2.0 mol ADP–ribose/mol of β/γ-actin, α-actin and γ-actin, respectively. The optimal pH for the ADP ribosylation was at pH 8.5, with the respective actin. Km values for NAD were calculated to be 30 μM with β/γ-actin, 35 μM with α-actin and 20 μM with γ-actin. The Km values for the actin isoforms were 15 μM for β/γ-actin, 2.5 μM for α-actin and 10 μM for γ-actin. ADP ribosylation of actin inhibited its capacity to polymerize, as determined by the increase in fluoresence intensity with N-(1-pyrenyl)iodoacetamide-labelled actin. Filamentous actin (F-actin) polymerized with the respective actin isoform was also ADP ribosylated, although the extent of the modification of F-actin was lower than that of globular actin (G-actin). In situ ADP ribosylation of β/γ-actin was evidenced with chicken peripheral heterophils permeabilized with saponin. Thus, the endogenous ADP ribosylation of actin in the heterophils may be involved in the cellular processes such as phagocytosis, secretion and migration.
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Arginine-specific ADP-ribosyltransferase and its acceptor protein p33 in chicken polymorphonuclear cells: co-localization in the cell granules, partial characterization, and in situ mono(ADP-ribosyl)ation.
Journal of biochemistry, 1991Co-Authors: Koichi Mishima, Masaharu Terashima, Kazuo Yamada, Seiji Obara, Katsuyuki Imai, Makoto ShimoyamaAbstract:We have reported the purification and characterization of arginine-specific ADP-ribosyltransferase from hen liver nuclei [Tanigawa, Y. et al. (1984) J. Biol. Chem. 259, 2022-2029] and the DNA-dependent mono(ADP-ribosyl)ation of p33, an acceptor protein in the nuclei [Mishima, K. et al. (1989) Eur. J. Biochem. 179, 267-273]. In the present study, we obtained evidence that among various tissues and cells from chicken, polymorphonuclear cells, so-called heterophils, possess both the ADP-ribosyltransferase and p33 at high levels. Percoll density gradient centrifugation of the postnuclear fraction of the heterophils revealed the co-localization of ADP-ribosyltransferase with p33 in the granule fraction. The enzyme and p33 were purified approximately 219- and 3.77-fold, respectively, from postnuclear pellet fraction to apparent homogeneity. The properties of heterophil ADP-ribosyltransferase and p33 were compared with those of the liver enzyme and p33. The molecular mass of the heterophil enzyme was estimated by SDS-polyacrylamide gel electrophoresis to be 27.5 kDa. The enzyme activity was stimulated by a sulfhydryl agent and inhibited by lysolecithin, NaCl, and inorganic phosphate. The mono(ADP-ribosyl)ation of p33 was markedly enhanced by polyanion, such as DNA, RNA, or poly(L-glutamate). SDS-polyacrylamide gel electrophoretic analysis after limited trypsin proteolysis of p33s, purified from chicken heterophils and liver, showed much the same pattern. Thus, it appears that ADP-ribosyltransferase and p33 present in heterophils are identical to those in the liver, respectively. p33 is considered to be an in situ substrate for ADP-ribosyltransferase, since it was specifically mono(ADP-ribosyl)ated in permeabilized heterophils.(ABSTRACT TRUNCATED AT 250 WORDS)
Christina L Swaggerty - One of the best experts on this subject based on the ideXlab platform.
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The avian heterophil.
Developmental and comparative immunology, 2013Co-Authors: Kenneth J Genovese, Christina L Swaggerty, Michael H. KogutAbstract: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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gene expression analysis of toll like receptor pathways in heterophils from genetic chicken lines that differ in their susceptibility to salmonella enteritidis
Frontiers in Genetics, 2012Co-Authors: Michael H. Kogut, Christina L Swaggerty, Hsini Chiang, Igal Y Pevzner, Huaijun ZhouAbstract:Previously conducted studies using two chicken lines (A and B) show that line A birds have increased resistance to a number of bacterial and protozoan challenges and that het- erophils isolated from line A birds are functionally more responsive. Furthermore, when stimulated withToll-like receptor (TLR) agonists, heterophils from line A expressed a totally different cytokine and chemokine mRNA expression pattern than heterophils from line B. A large-scale gene expression profile using an Agilent 44K microarray on heterophils isolated from line A and line B also revealed significantly differential expression in many immune-related genes following Salmonella enteritidis (SE) stimulation, which included genes involved in the TLR pathway. Therefore, we hypothesize the differences between the lines result from distinctive TLR pathway signaling cascades that mediate heterophil function and, thus, innate immune responsiveness to SE. Using quantitative RT-PCR on mRNA from heterophils isolated from control and SE-stimulated heterophils of each line, we profiled the expression of all chicken homologous genes identified in a reference TLR pathway. Several differentially expressed genes found were involved in the TLR-induced My88-dependent pathway, showing higher gene expression in line A than line B heterophils following SE stimulation. These genes included the TLR genes TLR4, TLR15, TLR21, MD-2, the adaptor proteins Toll-interleukin 1 receptor domain-containing adaptor protein (TIRAP ), Tumor necrosis factor-receptor associated factor 3 (TRAF3), the IkB kinases transforming growth factor-b-activating kinase 1 (TAK1), IKK+ and IKKa, the transcription factors NFkB2 and interferon regulatory factor 7, phosphatidylinositol-3 kinase (PI-3K ), and the mitogen- activated protein kinase p38. These results indicate that higher expression of TLR signaling activation of both MyD88-dependent and TRIF-dependent pathways are more beneficial to avian heterophil-mediated innate immunity and a complicated regulation of downstream adaptors is involved in stronger induction of a TLR-mediated innate response in the resis- tant line A.These findings identify new targets for genetic selection of chickens to increase resistance to bacterial infections.
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Differential mRNA expression of the avian-specific toll-like receptor 15 between heterophils from Salmonella-susceptible and -resistant chickens
Immunogenetics, 2009Co-Authors: Jessica R. Nerren, Kenneth J Genovese, Christina L Swaggerty, Kathryn M. Mackinnon, Igal Pevzner, Michael H. KogutAbstract:Pattern recognition receptors (PRRs) are essential for recognition of conserved molecular constituents found on infectious microbes. Toll-like receptors (TLRs) are a critical component of the PRR repertoire and are coupled to downstream production of cytokines, chemokines, and antimicrobial peptides by TLR adaptor proteins. Our laboratory previously demonstrated a role for TLR function in the differential innate response of two lines of chickens to bacterial infections. The aim of the present study was to elucidate the role of TLRs in the differential innate responsiveness by measuring differences between lines A (resistant) and B (susceptible) in heterophil mRNA expression of selected TLRs (TLRs 4, 5, and 15) and TLR adaptor proteins (MyD88, TRIF, and TIRAP) in response to stimulation with Salmonella enterica serovar Enteritidis (SE). Although heterophils from both lines had significantly increased expression of TLR 15 mRNA in response to stimulation with SE, heterophils from chickens resistant to infection with SE had significantly greater levels of TLR 15 mRNA expression prior to and following stimulation with SE than heterophils from chickens susceptible to infection with SE. No significant differences were noted between lines in nonstimulated levels of TIRAP, but upon SE stimulation, line A birds had higher levels of expression than B birds. No significant differences were found in heterophils between lines for mRNA expression of TLRs 4 and 5 nor MyD88 and TRIF. These data indicate that differences in the gene expression of TLR 15 by heterophils likely accounts for some of the observed differences between the lines in their susceptibility to infection.
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toll like receptor agonists stimulate differential functional activation and cytokine and chemokine gene expression in heterophils isolated from chickens with differential innate responses
Microbes and Infection, 2006Co-Authors: Michael H. Kogut, Christina L Swaggerty, I Y Pevzner, Peter K KaiserAbstract:Heterophils isolated from distinct broilers (lines A and B) differ in function and cytokine gene expression profiles. Nothing is known about Toll-like receptor (TLR) expression nor functional activation and cytokine/chemokine gene expression of line A and B heterophils when stimulated with TLR agonists. We found that line A and B heterophils express the same range of TLRs. All the bacterial TLR agonists, peptidoglycan, the synthetic lipoprotein Pam3CSK4, ultra-pure lipopolysaccharide, and flagellin all induced significantly greater functional activation of heterophils from line A compared to B. Only stimulation with the guanosine analog, loxoribine, (LOX) induced a significantly greater functional response in B over A. Additionally, all heterophils from line A stimulated with the bacterial TLR agonists had dramatic upregulation of pro-inflammatory cytokine and chemokine mRNA expression, whereas heterophils from line B had little or no upregulation of these genes. However, stimulation of all heterophils from line B with the bacterial TLR agonists and LOX induced a significant upregulation of IFN-α, with little transcription of this cytokine gene in line A heterophils. These findings suggest that the difference in heterophil functional efficiency between these parent lines is due to recognition of pathogens and activation of signaling pathways that induce innate cytokine and chemokine responses.
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Heterophil cytokine mRNA profiles from genetically distinct lines of chickens with differential heterophil-mediated innate immune responses
Avian pathology : journal of the W.V.P.A, 2006Co-Authors: Christina L Swaggerty, I Y Pevzner, Lisa Rothwell, Peter K Kaiser, Michael H. KogutAbstract:Previously we demonstrated that increased in-vitro heterophil function translates to increased in-vivo resistance to Salmonella enteritidis infections in broilers (line A > B). Heterophils produce cytokines and modulate acute protection against Salmonella in neonatal poultry. We hypothesized that heterophils from S. enteritidis-resistant chickens produce an up-regulated pro-inflammatory cytokine/chemokine response compared with S. enteritidis-susceptible chickens. In this study, heterophils were isolated 1, 14, and 28 days post-hatch, treated with RPMI or phagocytic agonists, and the cytokine/chemokine mRNA expression assessed using quantitative real-time reverse transcriptase-polymerase chain reaction. At all time-points, heterophils from S. enteritidis-resistant chickens (line A) had higher levels of pro-inflammatory cytokine/chemokine mRNA expression upon stimulation compared with heterophils from S. enteritidis-susceptible chickens (line B). Furthermore, heterophils from line A chickens had decreased mRNA expression of transforming growth factor-beta4, an anti-inflammatory cytokine, compared with line B. These data indicate a relationship between cytokine/chemokine mRNA expression by heterophils and determining overall immune competence. Therefore, heterophil functional efficiency, accompanied by evaluating cytokine/chemokines produced by heterophils, may be useful biomarkers for breeders to consider when developing new immunocompetent lines.
Pamela J. Ferro - One of the best experts on this subject based on the ideXlab platform.
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Heterophils are associated with resistance to systemic Salmonella enteritidis infections in genetically distinct chicken lines
FEMS immunology and medical microbiology, 2005Co-Authors: Christina L Swaggerty, I Y Pevzner, Pamela J. Ferro, Michael H. KogutAbstract:Heterophils mediate acute protection against Salmonella in young poultry. We evaluated susceptibility of genetically distinct lines of broilers to systemic Salmonella enteritidis (SE) infections. SE was administered into the abdomen of day-old chickens (parental lines [A and B]; F1 reciprocal crosses [C and D]) to assess modulation of leukocytes and survivability of chickens. Line A was more resistant to SE than line B; likewise cross D was more resistant than cross C. Significantly more heterophils migrated to the abdominal cavity post-infection in the resistant lines. These data indicate that increased heterophil influx to the infection site contributes to increased resistance against systemic SE infections in neonatal chickens.
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CpG-oligodeoxynucleotide-stimulated chicken heterophil degranulation is serum cofactor and cell surface receptor dependent.
Developmental and comparative immunology, 2005Co-Authors: Virginia K Lowry, Pamela J. Ferro, Michael H. KogutAbstract:Synthetic oligodeoxynucleotide containing unmethylated CpG motif (CpG-ODN) is immune stimulatory to chicken heterophils. Recognition of CpG-ODN by chicken heterophils leads to the mobilization and release of granules. This CpG-ODN-induced heterophil degranulation was chicken serum (CS)-dependent. Heat-denaturation and membrane filtration of CS revealed that the active serum cofactor(s) was likely a protein in nature with a molecule mass within 50,000 to 100,000. This serum cofactor(s) was heat-resistant at 56 °C for 1 h. The involvement of a cell surface receptor in recognition of CpG-ODN was also demonstrated by (1) trypsin treatment of the heterophils abrogated the degranulation response and (2) CpG-ODN-induced heterophil degranulation was sensitive to the inhibition of Clathrin-dependent endocytosis. In addition, among various microbial agonists, including CpG-ODN, lipopolysaccharide, lipoteichoic acid, phorbol myristate acetate, and formalin-killed Salmonella enteritidis, CpG-ODN was the only agonist that displayed serum-dependent induction of degranulation in chicken heterophils. This is the first report that shows serum-dependent activation of leukocytes by CpG-ODN.
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Recombinant chicken IL-6 does not activate heterophils isolated from day-old chickens in vitro.
Developmental and comparative immunology, 2005Co-Authors: Pamela J. Ferro, Lisa Rothwell, Christina L Swaggerty, Peter K Kaiser, Michael H. KogutAbstract:Pro-inflammatory cytokines are produced as part of innate immunity. Increased resistance to extraintestinal Salmonella enteritidis (SE) has been associated with an increase in heterophil pro-inflammatory cytokine gene expression. Invasion of chicken epithelial cells by SE induces an 8- to 10-fold increase in interleukin (IL) -6 production. Infection with SE induces an influx of heterophils to the site of infection; therefore, we hypothesize heterophils would be responsive to IL-6. The objective was to determine the effects of COS cell-derived recombinant chicken interleukin 6 (rChIL-6) on in vitro functional activity of heterophils. Heterophils were incubated with rChIL-6 or mock-transfected COS cell supernatant and functional activity was assessed. Heterophils treated with rChIL-6 showed no functional differences compared to controls. These data indicate rChIL-6, alone, does not affect the functional activity of neonatal chicken heterophils in vitro. Therefore, the function of IL-6 in the local environment in response to SE invasion is still unknown.
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Heterophils isolated from chickens resistant to extra-intestinal Salmonella enteritidis infection express higher levels of pro-inflammatory cytokine mRNA following infection than heterophils from susceptible chickens.
Epidemiology and infection, 2004Co-Authors: Pamela J. Ferro, I Y Pevzner, Christina L Swaggerty, Peter K Kaiser, Michael H. KogutAbstract:Previous studies showed differences in in vitro heterophil function between parental (A > B) broilers and F1 reciprocal crosses (D > C). Our objectives were to (1) determine if in vitro variations translate to differences in resistance to Salmonella enteritidis (SE) and (2) quantitate cytokine mRNA in heterophils from SE-infected chicks. One-day-old chicks were challenged and organs were cultured for SE. Chicks with efficient heterophils (A and D) were less susceptible to SE compared to chicks with inefficient heterophils (B and C). Heterophils were isolated from SE-infected chicks and cytokine mRNA expression was evaluated using quantitative real-time RT-PCR. Pro-inflammatory cytokine mRNA was up-regulated in heterophils from SE-resistant chicks compared to susceptible chicks. This is the first report to quantitate cytokine mRNA in heterophils from SE-infected chicks. These data show a relationship between in vitro heterophil function, increased pro-inflammatory cytokine mRNA expression, and increased resistance to SE in 1-day-old chicks.
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Differential cytokine mRNA expression in heterophils isolated from Salmonella-resistant and -susceptible chickens.
Immunology, 2004Co-Authors: Christina L Swaggerty, Michael H. Kogut, I Y Pevzner, Lisa Rothwell, Pamela J. Ferro, Peter K KaiserAbstract:SUMMARY We recently showed that increased in vitro heterophil functional efficiency translates to increased in vivo resistance to a systemic Salmonella enteritidis (SE) infection utilizing a parental pair of broiler chickens (lines A and B) and the F1 reciprocal crosses (C and D). Heterophils produce cytokines and modulate acute protection against Salmonella in young poultry. Therefore, we hypothesize that heterophils from SE-resistant chickens (A and D) have the ability to produce an up-regulated pro-inflammatory cytokine response compared to that of heterophils from SE-susceptible chickens (B and C). In this study, heterophils were isolated from day-old chickens and treated with either RPMI-1640 (as the control), or phagocytic agonists (SE, or SE opsonized with either normal chicken serum or immune serum against SE) and cytokine mRNA expression assessed using real-time quantitative reverse transcription– polymerase chain reaction. Heterophils from SE-resistant chickens (A and D) had significantly higher levels of pro-inflammatory cytokine (interleukin (IL)-6, IL-8, and IL-18) mRNA expression upon treatment with all agonists compared to heterophils from SE-susceptible lines (B and C). Further, heterophils from SE-resistant chickens had significantly decreased mRNA expression levels of transforming growth factor-b4, an anti-inflammatory cytokine, when compared to heterophils from SE-susceptible chickens. These data indicate cytokine gene expression in heterophils may be a useful parameter in determining resistance to Salmonella ,a s indicated by our previous in vivo SE studies. Therefore, heterophil functional efficiency and cytokine production may be useful biomarkers for poultry breeders to consider when developing new immunocompetent lines of birds.