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Michael H. Kogut - One of the best experts on this subject based on the ideXlab platform.

  • effect of induced molting on heterophil function in
    2016
    Co-Authors: Michael H. Kogut, Kenneth J Genovese, Larry H Stankera
    Abstract:

    SUMMARY. This study was undertaken to determine the effects of induced molt on basal functional activities of Heterophils from aging hens. For this purpose, Heterophils from both molted and unmolted hens were examined by in vitro bioassays for functional responsiveness and efficiency. We evaluated the ability of the Heterophils to migrate to chemotactic stimuli, phagocytize opsonized and nonopsonized Salmonella enteritidis (SE), and generate an oxidative burst in response to inflammatory agonists. A significant (P < 0.001) heterophilia was found in the molted hens within 2 days after feed withdrawal and remained throughout the length of the experimental feed withdrawal period. No significant differences were found in the random migration of Heterophils from either group. The chemotactic movement of Heterophils from molted hens was not affected until 8 days after feed withdrawal when compared with heterophil chemotaxis from unmolted hens. A significant decrease in chemotaxis by the Heterophils from molted hens was observed days 8-12 after feed withdrawal (P < 0.05). Significantly (P < 0.05) fewer Heterophils from molted hens were able to phagocytize opsonized (59% vs. 38%) and nonopsonized (26% vs. 15%) SE within 2 days after feed withdrawal. Likewise, significantly (P < 0.05) fewer bacteria were phagocytized per heterophil from the molted hens when compared with the number of bacteria per heterophil from the unmolted hens. The oxidative burst of Heterophils stimulated by either opsonized zymosan A or phorbol myristate acetate of Heterophils from molted hens was significantly (P < 0.05) reduced when compared with that generated by Heterophils from the unmolted hens. These results indicate that feed withdrawal to induce molt alters the number and function of peripheral blood Heterophils. This decreased efficiency of heterophil functional activity appears to play a role in the increased susceptibility of molting hens to SE infections.

  • The avian heterophil.
    Developmental and comparative immunology, 2013
    Co-Authors: Kenneth J Genovese, Christina L Swaggerty, Michael H. Kogut
    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.

  • 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, 2012
    Co-Authors: Michael H. Kogut, Christina L Swaggerty, Hsini Chiang, Igal Y Pevzner, Huaijun Zhou
    Abstract:

    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.

  • bacterial toll like receptor agonists induce sequential nf κb mediated leukotriene b4 and prostaglandin e2 production in chicken Heterophils
    Veterinary Immunology and Immunopathology, 2012
    Co-Authors: Michael H. Kogut, Kenneth J Genovese
    Abstract:

    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.

  • Differential mRNA expression of the avian-specific toll-like receptor 15 between Heterophils from Salmonella-susceptible and -resistant chickens
    Immunogenetics, 2009
    Co-Authors: Jessica R. Nerren, Kenneth J Genovese, Christina L Swaggerty, Kathryn M. Mackinnon, Igal Pevzner, Michael H. Kogut
    Abstract:

    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.

Peter K Kaiser - One of the best experts on this subject based on the ideXlab platform.

  • cytokine and chemokine gene expression profiles in Heterophils from chickens treated with corticosterone
    Stress, 2010
    Co-Authors: S Shini, A Shini, Peter K Kaiser
    Abstract:

    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.

  • 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, 2008
    Co-Authors: Michael H. Kogut, Kenneth J Genovese, Peter K Kaiser
    Abstract:

    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-...

  • 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, 2006
    Co-Authors: Michael H. Kogut, Christina L Swaggerty, I Y Pevzner, Peter K Kaiser
    Abstract:

    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.

  • 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, 2006
    Co-Authors: Christina L Swaggerty, I Y Pevzner, Lisa Rothwell, Peter K Kaiser, Michael H. Kogut
    Abstract:

    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.

  • Expression and function of Toll-like receptors in chicken Heterophils.
    Developmental and comparative immunology, 2005
    Co-Authors: Michael H. Kogut, Peter K Kaiser, Muhammad Iqbal, Victoria J. Philbin, Adrian Smith
    Abstract:

    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.

Christina L Swaggerty - One of the best experts on this subject based on the ideXlab platform.

  • The avian heterophil.
    Developmental and comparative immunology, 2013
    Co-Authors: Kenneth J Genovese, Christina L Swaggerty, Michael H. Kogut
    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.

  • 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, 2012
    Co-Authors: Michael H. Kogut, Christina L Swaggerty, Hsini Chiang, Igal Y Pevzner, Huaijun Zhou
    Abstract:

    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.

  • Differential mRNA expression of the avian-specific toll-like receptor 15 between Heterophils from Salmonella-susceptible and -resistant chickens
    Immunogenetics, 2009
    Co-Authors: Jessica R. Nerren, Kenneth J Genovese, Christina L Swaggerty, Kathryn M. Mackinnon, Igal Pevzner, Michael H. Kogut
    Abstract:

    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.

  • 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, 2006
    Co-Authors: Michael H. Kogut, Christina L Swaggerty, I Y Pevzner, Peter K Kaiser
    Abstract:

    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.

  • 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, 2006
    Co-Authors: Christina L Swaggerty, I Y Pevzner, Lisa Rothwell, Peter K Kaiser, Michael H. Kogut
    Abstract:

    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.

  • Heterophils are associated with resistance to systemic Salmonella enteritidis infections in genetically distinct chicken lines
    FEMS immunology and medical microbiology, 2005
    Co-Authors: Christina L Swaggerty, I Y Pevzner, Pamela J. Ferro, Michael H. Kogut
    Abstract:

    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.

  • CpG-oligodeoxynucleotide-stimulated chicken heterophil degranulation is serum cofactor and cell surface receptor dependent.
    Developmental and comparative immunology, 2005
    Co-Authors: Virginia K Lowry, Pamela J. Ferro, Michael H. Kogut
    Abstract:

    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.

  • Recombinant chicken IL-6 does not activate Heterophils isolated from day-old chickens in vitro.
    Developmental and comparative immunology, 2005
    Co-Authors: Pamela J. Ferro, Lisa Rothwell, Christina L Swaggerty, Peter K Kaiser, Michael H. Kogut
    Abstract:

    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.

  • 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, 2004
    Co-Authors: Pamela J. Ferro, I Y Pevzner, Christina L Swaggerty, Peter K Kaiser, Michael H. Kogut
    Abstract:

    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.

  • Differential cytokine mRNA expression in Heterophils isolated from Salmonella-resistant and -susceptible chickens.
    Immunology, 2004
    Co-Authors: Christina L Swaggerty, Michael H. Kogut, I Y Pevzner, Lisa Rothwell, Pamela J. Ferro, Peter K Kaiser
    Abstract:

    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.

Virginia K Lowry - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of MAP and tyrosine kinase signaling in Heterophils from commercial and wild-type turkeys.
    Developmental and comparative immunology, 2007
    Co-Authors: Kenneth J Genovese, Virginia K Lowry, Michael H. Kogut
    Abstract:

    Abstract Protein tyrosine and mitogen-activated kinases are crucial mediators of the host innate immune response, conferring signals from surface receptors on the host cell to the nucleus of the cell where gene expression occurs. Heterophils were isolated from wild-type Rio Grande turkeys and a commercial line of turkeys (Line A) on days 4 and 7 post-hatch. Heterophils were stimulated for 1 h with Salmonella enteritidis (SE) or opsonized SE (OPSE). After stimulation, cells were lysed and lysates were tested for mitogen-activated protein kinase (MAPK) activity. Specifically, phosphorylation of extracellular signal-regulated protein kinase (ERK1/2) and p38 MAPK phosphorylation were assayed using commercially available ELISA kits. Total protein tyrosine kinase (PTK) activity was also assayed. On both days 4 and 7 post-hatch, Heterophils from Rio Grande turkeys had significantly higher levels of ERK 1/2 and p38 MAPK kinase activity upon stimulation with either SE or OPSE ( p 0.001 ). Likewise, PTK values on days 4 and 7 in Rio Grande turkey Heterophils were significantly higher upon stimulation with SE than with OPSE and were significantly ( p 0.001 ) higher than PTK levels in Line A upon SE and OPSE stimulation. The data presented supports previous heterophil functional comparison studies wherein Heterophils from Rio Grande turkeys had higher levels of oxidative burst and degranulation activities as compared to the activity observed in commercial Line A Heterophils. This suggests that the regulation and control of these functions are mediated by protein tyrosine and mitogen-activated kinases. Furthermore, the data suggest that selection of commercial lines of turkeys for larger, heavier bodies, and faster growth may be associated with subsequent selection for decreased innate immune functions related to intracellular signaling mechanisms and possibly a subsequent increase in susceptibility to disease.

  • Comparison of heterophil functions of modern commercial and wild-type Rio Grande turkeys.
    Avian pathology : journal of the W.V.P.A, 2006
    Co-Authors: Kenneth J Genovese, Virginia K Lowry, Christina L Swaggerty, Michael H. Kogut
    Abstract:

    The purpose of the present study was to measure any functional differences in peripheral blood Heterophils isolated from a commercial turkey line to wild-type Rio Grande turkeys. The phagocytosis of Salmonella enteritidis, oxidative burst (OXB) and degranulation (DGR) were used as parameters of heterophil functional efficiency in these studies. Blood was collected and Heterophils isolated from each line of turkeys at days 4, 7, and 14 post-hatch. On days 4 and 7 post-hatch, Heterophils from Rio Grande turkeys responded to phorbol A-myristate-13-acetate with significantly greater OXB activity than commercial line A. Results from the DGR assay also revealed a greater level of activity in Rio Grande Heterophils when compared with Heterophils from Line A turkeys. On day 14 post-hatch, Heterophils from the commercial line A responded at similar or greater levels than Rio Grande turkey Heterophils in the OXB and DGR assays. No differences in the phagocytosis of S. enteritidis were observed between the lines. Th...

  • CpG-oligodeoxynucleotide-stimulated chicken heterophil degranulation is serum cofactor and cell surface receptor dependent.
    Developmental and comparative immunology, 2005
    Co-Authors: Virginia K Lowry, Pamela J. Ferro, Michael H. Kogut
    Abstract:

    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.

  • the use of selective pharmacological inhibitors to delineate signal transduction pathways activated during complement receptor mediated degranulation in chicken Heterophils
    International Immunopharmacology, 2003
    Co-Authors: Michael H. Kogut, Virginia K Lowry, M B Farnell
    Abstract:

    Abstract Complement receptors (CRs), along with Fc receptors, play a primary role in the removal of bacterial pathogens in poultry. The binding of serum-opsonized bacteria to CR results in the secretion of both toxic oxygen metabolites and antibacterial granules. We have previously shown that the stimulation of chicken Heterophils with serum-opsonized Salmonella enteritidis induced tyrosine kinase-dependent phosphorylation regulated degranulation. In the present studies, we used selective pharmacological inhibitors to investigate the roles of protein tyrosine kinases, phospholipases C and D (PLC and PLD), phosphatidylinositol 3′-kinase (PI3-K), and the super family of mitogen-activated protein kinases (MAPKs) on CR-mediated heterophil degranulation. Inhibitors of receptor-linked tyrosine kinases (the tryphostins AG1478 and AG1296) had no attenuating effects on CR-mediated degranulation. However, PP2, a selective inhibitor of the src family of protein tyrosine kinases, and piceatannol, an inhibitor of Syk tyrosine kinases, both significantly attenuated the CR-mediated degranulation. Additionally, the specific inhibitors of PLC, U73122, and PI3-K, LY294002, significantly decreased CR-mediated heterophil degranulation. Two inhibitors of PLD-mediated signaling, 2,3-diphosphoglycerate (2,3-DPG) and 1-butanol, hindered degranulation. Addition of purified PLD restored control levels of degranulation in Heterophils in which PLD was inhibited. Lastly, SP600125, a selective inhibitor of c-Jun N-terminal kinase (JNK), inhibited degranulation; whereas neither PD98059, the inhibitor of p38 MAPK, nor SB203580, the inhibitor of extracellular signal-regulated kinase, had any effect on CR-mediated heterophil degranulation. These studies demonstrate that CRs on chicken Heterophils lack intrinsic tyrosine kinase activity, but that binding of serum-opsonized bacteria activates both proximal tyrosine kinases ( src and Syk kinases), but differentially activates downstream tyrosine kinases (JNK, but not p38 nor ERK). Activation of src and Syk kinases plays a significant role in signal transduction of heterophil degranulation probably by stimulating downstream phosphorylation of PLC, PLD, and PI3-K. PI3-K has also been recently shown to be an upstream mediator of JNK activation, suggesting that this enzyme can induce signaling as both a lipid kinase and protein kinase. Engaging CRs on chicken Heterophils activates a proximal tyrosine kinase ( src and Syk kinases)→PLC (PLD)→PI3-K→JNK signal transduction pathway that induces degranulation.

  • functional comparison of Heterophils isolated from commercial broiler chickens
    Avian Pathology, 2003
    Co-Authors: Christina L Swaggerty, Virginia K Lowry, I Y Pevzner, M B Farnell, Michael H. Kogut
    Abstract:

    Heterophils from two pure lines (A and B) of commercial broiler chickens were isolated on days 1, 4, and 7 post-hatch to evaluate their ability to (1) phagocytose Salmonella enteritidis (SE) (2) degranulate when exposed to immune-IgG opsonized SE, and (3) produce an oxidative burst. On days 1 and 4, Heterophils from line A were functionally more efficient compared to Heterophils from line B (p<0.05). By 7 days post hatch, heterophil functions for both lines were comparable. To further study the inheritance of heterophil functional efficiency, F1 reciprocal crosses (line C=male B×female A; line D=male A×female B) were evaluated for functional activity and compared with the immunologically efficient (A) and non-efficient (B) parent lines. Heterophils from line D had a more efficient heterophil function (p<0.05) when compared to Heterophils from C. These results suggest that heterophil function and efficiency can be genetically transferred to progeny. Moreover they indicate that heterophil function is sex...