1
|
Stewart EL, Counoupas C, Steain M, Ashley C, Alca S, Hartley-Tassell L, von Itzstein M, Britton WJ, Petrovsky N, Triccas JA. Dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) is a cellular receptor for delta inulin adjuvant. Immunol Cell Biol 2024; 102:593-604. [PMID: 38757764 PMCID: PMC11296934 DOI: 10.1111/imcb.12774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/21/2024] [Accepted: 04/29/2024] [Indexed: 05/18/2024]
Abstract
Delta inulin, or Advax, is a polysaccharide vaccine adjuvant that significantly enhances vaccine-mediated immune responses against multiple pathogens and was recently licensed for use in the coronavirus disease 2019 (COVID-19) vaccine SpikoGen. Although Advax has proven effective as an immune adjuvant, its specific binding targets have not been characterized. In this report, we identify a cellular receptor for Advax recognition. In vitro uptake of Advax particles by macrophage cell lines was substantially greater than that of latex beads of comparable size, suggesting an active uptake mechanism by phagocytic cells. Using a lectin array, Advax particles were recognized by lectins specific for various carbohydrate structures including mannosyl, N-acetylgalactosamine and galactose moieties. Expression in nonphagocytic cells of dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), a C-type lectin receptor, resulted in enhanced uptake of fluorescent Advax particles compared with mock-transfected cells. Advax uptake was reduced with the addition of ethylenediaminetetraacetic acid and mannan to cells, which are known inhibitors of DC-SIGN function. Finally, a specific blockade of DC-SIGN using a neutralizing antibody abrogated Advax uptake in DC-SIGN-expressing cells. Together, these results identify DC-SIGN as a putative receptor for Advax. Given the known immunomodulatory role of DC-SIGN, the findings described here have implications for the use of Advax adjuvants in humans and inform future mechanistic studies.
Collapse
Affiliation(s)
- Erica L Stewart
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- Centre for Infection and Immunity, Centenary Institute, The University of Sydney, Camperdown NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| | - Claudio Counoupas
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- Centre for Infection and Immunity, Centenary Institute, The University of Sydney, Camperdown NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| | - Megan Steain
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| | - Caroline Ashley
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| | - Sibel Alca
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| | | | - Mark von Itzstein
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Warwick J Britton
- Centre for Infection and Immunity, Centenary Institute, The University of Sydney, Camperdown NSW 2006, Australia
| | | | - James A Triccas
- Sydney Infectious Diseases Institute (Sydney ID), Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- Centre for Infection and Immunity, Centenary Institute, The University of Sydney, Camperdown NSW 2006, Australia
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown NSW 2006, Australia
| |
Collapse
|
2
|
Candian V, Tedeschi R. Impact of the Diet on the Mortality and on Gene Expression of the Antimicrobial Peptide Tenecin 3 in Tenebrio molitor Larvae Infected by Beauveria bassiana. INSECTS 2023; 14:359. [PMID: 37103174 PMCID: PMC10146776 DOI: 10.3390/insects14040359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 03/31/2023] [Accepted: 04/02/2023] [Indexed: 06/19/2023]
Abstract
Large-scale insect rearing can be subjected to microbial infections, leading to serious economic losses. When possible, the use of antibiotics is to be avoided for insects intended as feed or food and new strategies to preserve the health of the farmed insects are required. The effectiveness of insect immune system depends on several factors, including the nutritional composition of the diet. The possibility to modulate immune responses through the diet is currently a topic of great interest from an application point of view. We evaluated the effect of two different diets on the survival rate and gene expression of the antimicrobial peptide Tenecin 3 in uninfected and Beauveria bassiana-infected Tenebrio molitor L. larvae. A wheat bran diet, mixed 50% with brewers' spent grains, could positively influence the expression of Tenecin 3 gene when uninfected T. molitor is allowed to develop on such a substrate from early larval stages. Even if, in our trial, the diet with added brewers' spent grains could not reduce the mortality of the larvae infected with B. bassiana, higher transcriptional levels of the antifungal peptide were observed in insects fed this diet, depending on the timing of diet administration.
Collapse
|
3
|
Krachler AM, Sirisaengtaksin N, Monteith P, Paine CET, Coates CJ, Lim J. Defective phagocyte association during infection of Galleria mellonella with Yersinia pseudotuberculosis is detrimental to both insect host and microbe. Virulence 2021; 12:638-653. [PMID: 33550901 PMCID: PMC7889024 DOI: 10.1080/21505594.2021.1878672] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/13/2021] [Accepted: 01/15/2021] [Indexed: 11/03/2022] Open
Abstract
Adhesins facilitate bacterial colonization and invasion of host tissues and are considered virulence factors, but their impact on immune-mediated damage as a driver of pathogenesis remains unclear. Yersinia pseudotuberculosis encodes for a multivalent adhesion molecule (MAM), a mammalian cell entry (MCE) family protein and adhesin. MAMs are widespread in Gram-negative bacteria and enable enteric bacteria to colonize epithelial tissues. Their role in bacterial interactions with the host innate immune system and contribution to pathogenicity remains unclear. Here, we investigated howY. pseudotuberculosis MAM contributes to pathogenesis during infection of the Galleria mellonella insect model. We show that Y. pseudotuberculosis MAM is required for efficient bacterial binding and uptake by hemocytes, the host phagocytes. Y. pseudotuberculosis interactions with insect and mammalian phagocytes are determined by bacterial and host factors. Loss of MAM, and deficient microbe-phagocyte interaction, increased pathogenesis in G. mellonella. Diminished phagocyte association also led to increased bacterial clearance. Furthermore, Y. pseudotuberculosis that failed to engage phagocytes hyperactivated humoral immune responses, most notably melanin production. Despite clearing the pathogen, excessive melanization also increased phagocyte death and host mortality. Our findings provide a basis for further studies investigating how microbe- and host-factors integrate to drive pathogenesis in a tractable experimental system.
Collapse
Affiliation(s)
- Anne Marie Krachler
- Department of Microbiology and Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, TX, USA
| | - Natalie Sirisaengtaksin
- Department of Microbiology and Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, TX, USA
| | - Pauline Monteith
- Biological and Environmental Sciences, University of Stirling, Stirling, UK
| | - C. E. Timothy Paine
- School of Environmental and Rural Sciences, University of New England, Armidale, Australia
| | - Christopher J. Coates
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales UK
| | - Jenson Lim
- Biological and Environmental Sciences, University of Stirling, Stirling, UK
| |
Collapse
|
4
|
Kim SG, Jo YH, Seong JH, Park KB, Noh MY, Cho JH, Ko HJ, Kim CE, Tindwa H, Patnaik BB, Bang IS, Lee YS, Han YS. TmSR-C, scavenger receptor class C, plays a pivotal role in antifungal and antibacterial immunity in the coleopteran insect Tenebrio molitor. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 89:31-42. [PMID: 28867469 DOI: 10.1016/j.ibmb.2017.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 08/15/2017] [Accepted: 08/24/2017] [Indexed: 06/07/2023]
Abstract
Scavenger receptors (SRs) constitute a family of membrane-bound receptors that bind to multiple ligands. The SR family of proteins is involved in removing cellular debris, oxidized low-density lipoproteins, and pathogens. Specifically, class C scavenger receptors (SR-C) have also been reported to be involved in phagocytosis of gram-positive and -negative bacteria in Drosophila and viruses in shrimp. However, reports are unavailable regarding the role of SR-C in antifungal immune mechanisms in insects. In this study, a full-length Tenebrio molitor SR-C (TmSR-C) sequence was obtained by 5'- and 3'-Rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The TmSR-C full-length cDNA comprised 1671 bp with 5'- and 3'-untranslated regions of 23- and 107-bp, respectively. TmSR-C encodes a putative protein of 556 amino acid residues that is constitutively expressed in all tissues of late instar larvae and 2-day-old adults, with the highest transcript levels observed in hemocytes of larvae and adults. TmSR-C mRNA showed a 2.5-fold and 3-fold increase at 24 and 6 h after infection with Candida albicans and β-glucan, respectively. Immunoassay with TmSR-C polyclonal antibody showed induction of the putative protein in the cytosols of hemocytes at 3 h after inoculation of C. albicans. RNA interference (RNAi)-based gene silencing and phagocytosis assays were used to understand the role of TmSR-C in antifungal immunity. Silencing of TmSR-C transcripts reduced the survivability of late instar larvae at 2 days post-inoculation of C. albicans, Escherichia coli, or Staphylococcus aureus. Furthermore, in TmSR-C-silenced larvae, there was a decline in the rate of microorganism phagocytosis. Taken together, results of this study suggest that TmSR-C plays a pivotal role in phagocytosing not only fungi but also gram-negative and -positive bacteria in T. molitor.
Collapse
Affiliation(s)
- Soo Gon Kim
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Yong Hun Jo
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jeong Hwan Seong
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Ki Beom Park
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Mi Young Noh
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jun Ho Cho
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Hye Jin Ko
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Chang Eun Kim
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Hamisi Tindwa
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea; Department of Soil and Geological Sciences, (Soil Microbiology Section), College of Agriculture, Sokoine University of Agriculture, P.O. Box 3008, Chuo Kikuu, Morogoro, Tanzania
| | - Bharat Bhusan Patnaik
- School of Biotech Sciences, Trident Academy of Creative Technology (TACT), F2-B, Chandaka Industrial Estate, Chandrasekharpur, Bhubaneswar, 751024, Odisha, India
| | - In Seok Bang
- Department of Biological Science, Hoseo University, Asan, Republic of Korea
| | - Yong Seok Lee
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, Asan City, 336-745, Republic of Korea
| | - Yeon Soo Han
- Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea.
| |
Collapse
|
5
|
Satyavathi VV, Narra D, Nagaraju J. Noduler an immune protein augments infection-induced cell proliferation through cross-talking with p38 MAPK. Immunobiology 2016; 221:387-97. [DOI: 10.1016/j.imbio.2015.09.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 08/02/2015] [Accepted: 09/10/2015] [Indexed: 12/01/2022]
|
6
|
Casanova-Torres ÁM, Goodrich-Blair H. Immune Signaling and Antimicrobial Peptide Expression in Lepidoptera. INSECTS 2013; 4:320-38. [PMID: 25861461 PMCID: PMC4386667 DOI: 10.3390/insects4030320] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Revised: 06/21/2013] [Accepted: 06/21/2013] [Indexed: 02/06/2023]
Abstract
Many lepidopteran insects are agricultural pests that affect stored grains, food and fiber crops. These insects have negative ecological and economic impacts since they lower crop yield, and pesticides are expensive and can have off-target effects on beneficial arthropods. A better understanding of lepidopteran immunity will aid in identifying new targets for the development of specific insect pest management compounds. A fundamental aspect of immunity, and therefore a logical target for control, is the induction of antimicrobial peptide (AMP) expression. These peptides insert into and disrupt microbial membranes, thereby promoting pathogen clearance and insect survival. Pathways leading to AMP expression have been extensively studied in the dipteran Drosophila melanogaster. However, Diptera are an important group of pollinators and pest management strategies that target their immune systems is not recommended. Recent advances have facilitated investigation of lepidopteran immunity, revealing both conserved and derived characteristics. Although the general pathways leading to AMP expression are conserved, specific components of these pathways, such as recognition proteins have diverged. In this review we highlight how such comparative immunology could aid in developing pest management strategies that are specific to agricultural insect pests.
Collapse
|
7
|
Porter K, Lin Y, Liton PB. Cathepsin B is up-regulated and mediates extracellular matrix degradation in trabecular meshwork cells following phagocytic challenge. PLoS One 2013; 8:e68668. [PMID: 23844232 PMCID: PMC3700899 DOI: 10.1371/journal.pone.0068668] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 06/01/2013] [Indexed: 12/24/2022] Open
Abstract
Cells in the trabecular meshwork (TM), a tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic activity in TM cells is thought to play an important role in outflow pathway physiology. However, the molecular mechanisms triggered by phagocytosis in TM cells are unknown. Here we investigated the effects of chronic phagocytic stress on lysosomal function using different phagocytic ligands (E. coli, carboxylated beads, collagen I-coated beads, and pigment). Lysotracker red co-localization and electron micrographs showed the maturation of E. coli- and collagen I-coated beads-containing phagosomes into phagolysosomes. Maturation of phagosomes into phagolysosomes was not observed with carboxylated beads or pigment particles. In addition, phagocytosis of E. coli and collagen I-coated beads led to increased lysosomal mass, and the specific up-regulation and activity of cathepsin B (CTSB). Higher levels of membrane-bound and secreted CTSB were also detected. Moreover, in vivo zymography showed the intralysosomal degradation of ECM components associated with active CTSB, as well as an overall increased gelatinolytic activity in phagocytically challenged TM cells. This increased gelatinolytic activity with phagocytosis was partially blocked with an intracellular CTSB inhibitor. Altogether, these results suggest a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.
Collapse
Affiliation(s)
- Kristine Porter
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Yizhi Lin
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Paloma B. Liton
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
8
|
Insight on signal transduction pathways involved in phagocytosis in the colonial ascidian Botryllus schlosseri. J Invertebr Pathol 2013; 112:260-6. [DOI: 10.1016/j.jip.2012.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/05/2012] [Accepted: 12/08/2012] [Indexed: 11/20/2022]
|
9
|
Porter KM, Epstein DL, Liton PB. Up-regulated expression of extracellular matrix remodeling genes in phagocytically challenged trabecular meshwork cells. PLoS One 2012; 7:e34792. [PMID: 22529935 PMCID: PMC3329506 DOI: 10.1371/journal.pone.0034792] [Citation(s) in RCA: 26] [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: 10/06/2011] [Accepted: 03/08/2012] [Indexed: 11/18/2022] Open
Abstract
Background Cells in the trabecular meshwork (TM), the tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic function in TM cells is thought to play an important role in the normal functioning of the outflow pathway. Dysfunction of phagocytosis could lead to abnormalities of outflow resistance and increased intraocular pressure (IOP). However, the molecular mechanisms triggered by phagocytosis in TM cells are completely unknown. Methodology/Principal Findings Gene expression profile analysis of human TM cells phagocytically challenged to E. coli or pigment under physiological and oxidative stress environment were performed using Affymetrix U133 plus 2.0 array and analyzed with Genespring GX. Despite the differential biological response elicited by E. coli and pigment particles, a number of genes, including MMP1, MMP3, TNFSF11, DIO2, KYNU, and KCCN2 showed differential expression with both phagocytic ligands in all conditions. Data was confirmed by qPCR in both human and porcine TM cells. Metacore pathway analysis and the usage of recombinant adenovirus encoding the dominant negative mutant of IkB identified NF-κB as a transcription factor mediating the up-regulation of at least MMP1 and MMP3 in TM cells with phagocytosis. In-gel zymography demonstrated increased collagenolytic and caseinolytic activities in the culture media of TM cells challenge to E. coli. In addition, collagenolytic I activity was further confirmed using the self-quenched fluorescent substrate DQ-Collagen I. Conclusions/Significance Here we report for the first time the differential gene expression profile of TM cells phagocytically challenged with either E. coli or pigment. Our data indicate a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.
Collapse
Affiliation(s)
| | | | - Paloma B. Liton
- Duke University, Department of Ophthalmology, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
10
|
Moon AE, Walker AJ, Goodbourn S. Regulation of transcription of the Aedes albopictus cecropin A1 gene: A role for p38 mitogen-activated protein kinase. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:628-636. [PMID: 21501684 DOI: 10.1016/j.ibmb.2011.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 03/22/2011] [Accepted: 04/01/2011] [Indexed: 05/30/2023]
Abstract
Regulation of the Aedes albopictus cecropin A1 promoter was studied to provide insight into the transcriptional control of this antimicrobial peptide (AMP) gene in mosquitoes. Gene expression levels of cecropin A1 increased in A. albopictus C6/36 cells in response to heat-killed Escherichiacoli. Reporter gene assays incorporating -757 to +32 of the A. albopictus cecropin A1 promoter revealed that E. coli could induce expression in these cells with more pronounced expression than that seen with lipopolysaccharide (LPS). Analysis of deletion constructs demonstrated that the 5' boundary of the regulatory region for the activation of this AMP was located between -173 and -64. Western blotting with anti-phospho-specific antibodies demonstrated that p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK) were activated by LPS, whereas only p38 MAPK was activated by E. coli. Moreover, pharmacological experiments revealed that pre-incubation of cells with the p38 MAPK inhibitor SB203580 resulted in a striking activation of the cecropin A1 promoter following immune challenge, demonstrating that p38 MAPK negatively regulates cecropin A1 promoter activity. Finally the region required for the negative regulation by p38 MAPK was identified as being between -173 and -64. This report is the first to show involvement of the p38 MAPK pathway in the negative regulation of AMP production in a mosquito.
Collapse
Affiliation(s)
- Alice E Moon
- School of Life Sciences, Kingston University, Kingston upon Thames, Surrey KT1 2EE, UK
| | | | | |
Collapse
|
11
|
Arbi M, Pouliliou S, Lampropoulou M, Marmaras VJ, Tsakas S. Hydrogen peroxide is produced by E. coli challenged haemocytes and regulates phagocytosis, in the medfly Ceratitis capitata. The active role of superoxide dismutase. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2011; 35:865-871. [PMID: 21527279 DOI: 10.1016/j.dci.2011.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 03/15/2011] [Accepted: 03/16/2011] [Indexed: 05/30/2023]
Abstract
Hydrogen peroxide (H(2)O(2)) participates as a second messenger in cell signaling. In this paper, the role of H(2)O(2) was investigated, in Escherichia coli phagocytosis by the haemocytes of the medfly Ceratitis capitata. Block of H(2)O(2) synthesis by specific enzymic inhibitors, namely N-ethylmaleimide (NEM) for NADPH oxidase and diethyldithiocarbamate (DDC) for SOD, resulted in the increase of E. coli phagocytosis. Immunoblot analysis, flow cytometry and confocal microscopy, revealed the constitutive expression of SOD, in the medfly haemocytes. Phagocytosis increased by small interfering RNA (siRNA) for SOD, revealing the active involvement of SOD and H(2)O(2). Immunoblot analysis showed an increase of the ERK1/2 phosphorylation, in the presence of the above H(2)O(2) synthesis enzymic inhibitors. In addition, confocal microscopy showed no co-localization of SOD with β integrin subunit. It appears that SOD participates in the regulation of bacterial phagocytosis, due to involvement of the produced H(2)O(2) in the differential phosphorylation of MAP kinases.
Collapse
Affiliation(s)
- Marina Arbi
- Laboratory of Biology, Department of Biology, University of Patras, Greece
| | | | | | | | | |
Collapse
|
12
|
Lee S, Shrestha S, Prasad SV, Kim Y. Role of a small G protein Ras in cellular immune response of the beet armyworm, Spodoptera exigua. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:356-362. [PMID: 21167168 DOI: 10.1016/j.jinsphys.2010.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 12/06/2010] [Accepted: 12/08/2010] [Indexed: 05/30/2023]
Abstract
Insect cellular immune responses accompany cytoskeletal rearrangement of hemocytes to exhibit filopodial and pseudopodial extension of their cytoplasm. Small G proteins are postulated to be implicated in the hemocyte cellular processes to perform phagocytosis, nodulation, and encapsulation behaviors. A small G protein ras gene (Se-Ras) was cloned from cDNAs prepared from hemocytes of the beet armyworm, Spodoptera exigua. The open reading frame of Se-Ras encoded 179 amino acids with a predicted molecular weight of 20.0kDa, in which 114 residues at amino terminus were predicted to be a GTP binding domain. It showed high sequence similarities (86.1-92.8%) with known ras genes in other insects. Se-Ras was constitutively expressed in all developmental stages from egg to adult without any significant change in expression levels in response to bacterial challenge. A specific double strand RNA (dsRNA) could knockdown its expression in the hemocytes after 48h post-injection. While the RNA interference (RNAi) did not show any change in total or differential hemocyte counts, it impaired hemocyte behaviors. The RNAi of Se-Ras significantly suppressed hemocyte spreading, cytoskeleton extension, and nodulation behaviors in response to bacterial challenge. Release of prophenoloxidase from oenocytoids was significantly inhibited by the RNAi, which resulted in significant suppression in PO activation in response to an inducer, PGE(2). These results suggest that Se-Ras is implicated in mediating cellular processes of S. exigua hemocytes. This is the first report of Ras role in insect cellular immune response.
Collapse
Affiliation(s)
- Seeon Lee
- Department of Molecular and Cell Biology, Liberal Arts and Science, University of Illinois, Urbana-Champaign, IL 61801, USA
| | | | | | | |
Collapse
|
13
|
Altincicek B, Berisha A, Mukherjee K, Spengler B, Römpp A, Vilcinskas A. Identification of collagen IV derived danger/alarm signals in insect immunity by nanoLC-FTICR MS. Biol Chem 2009; 390:1303-11. [DOI: 10.1515/bc.2009.128] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
AbstractThe immune system can be stimulated by microbial molecules as well as by endogenously derived danger/alarm signals of host origin. Using the lepidopteran model insectGalleria mellonella, we recently discovered that fragments of collagen IV, resulting from hydrolysis by microbial metalloproteinases, represent danger/alarm signals in insects. Here, we characterized immune-stimulatory peptides generated by thermolysin-mediated degradation of collagen IV using nanospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) after separation by nanoscale liquid chromatography (nanoLC). The combination of FTICR MS analysis andde novopeptide sequencing resulted in the identification of 38 specific collagen IV fragments of which several peptides included the integrin-binding motif RGD/E known from numerous mammalian immune-related proteins. Custom-synthesized peptides corresponding either to the presently identified collagen peptide GIRGEHyp or to a well-known integrin-binding RGD peptide (GRGDS) were injected intoG. mellonellato determine their immune-stimulatory activitiesin vivo. Both peptides stimulated immune cells and systemically the expression of lysozyme and a specific inhibitor of microbial metalloproteinases. Further examination using specific MAP kinase inhibitors indicated that MEK/ERK and p38 are involved in RGD/E-mediated immune-signaling pathways, whereas JNK seems to play only a minor role.
Collapse
|
14
|
Mamali I, Lamprou I, Karagiannis F, Karakantza M, Lampropoulou M, Marmaras VJ. A beta integrin subunit regulates bacterial phagocytosis in medfly haemocytes. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2009; 33:858-866. [PMID: 19428487 DOI: 10.1016/j.dci.2009.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 02/10/2009] [Accepted: 02/13/2009] [Indexed: 05/27/2023]
Abstract
We have recently reported that the activation of focal adhesion kinase (FAK) and its downstream targets upon pathogen challenge regulate phagocytosis in medfly haemocytes. The goal of this study was to further explore the signalling pathway underlying the process of phagocytosis. In particular, in this report, we used flow cytometry, RNA interference, enzyme-linked immunosorbent assay, Western blot and immunoprecipitation analysis to demonstrate the haemocyte surface receptor, through which the extracellular signals in response to bacteria are transmitted intracellularly. The presented data demonstrate the expression of a beta integrin subunit in the surface of medfly haemocytes that transmits signals upon pathogen triggering to FAK and its downstream targets, Src, MAP kinases and Elk-1-like protein, for the engulfment of pathogen. Interestingly LPS is not internalized through integrins.
Collapse
Affiliation(s)
- Irene Mamali
- Department of Biology, University of Patras, Patras, Greece
| | | | | | | | | | | |
Collapse
|
15
|
Marmaras VJ, Lampropoulou M. Regulators and signalling in insect haemocyte immunity. Cell Signal 2009; 21:186-95. [DOI: 10.1016/j.cellsig.2008.08.014] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 08/24/2008] [Indexed: 02/06/2023]
|
16
|
Sulahian TH, Imrich A, Deloid G, Winkler AR, Kobzik L. Signaling pathways required for macrophage scavenger receptor-mediated phagocytosis: analysis by scanning cytometry. Respir Res 2008; 9:59. [PMID: 18687123 PMCID: PMC2527561 DOI: 10.1186/1465-9921-9-59] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Accepted: 08/07/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Scavenger receptors are important components of the innate immune system in the lung, allowing alveolar macrophages to bind and phagocytose numerous unopsonized targets. Mice with genetic deletions of scavenger receptors, such as SR-A and MARCO, are susceptible to infection or inflammation from inhaled pathogens or dusts. However, the signaling pathways required for scavenger receptor-mediated phagocytosis of unopsonized particles have not been characterized. METHODS We developed a scanning cytometry-based high-throughput assay of macrophage phagocytosis that quantitates bound and internalized unopsonized latex beads. This assay allowed the testing of a panel of signaling inhibitors which have previously been shown to target opsonin-dependent phagocytosis for their effect on unopsonized bead uptake by human in vitro-derived alveolar macrophage-like cells. The non-selective scavenger receptor inhibitor poly(I) and the actin destabilizer cytochalasin D were used to validate the assay and caused near complete abrogation of bead binding and internalization, respectively. RESULTS Microtubule destabilization using nocodazole dramatically inhibited bead internalization. Internalization was also significantly reduced by inhibitors of tyrosine kinases (genistein and herbimycin A), protein kinase C (staurosporine, chelerythrine chloride and Gö 6976), phosphoinositide-3 kinase (LY294002 and wortmannin), and the JNK and ERK pathways. In contrast, inhibition of phospholipase C by U-73122 had no effect. CONCLUSION These data indicate the utility of scanning cytometry for the analysis of phagocytosis and that phagocytosis of unopsonized particles has both shared and distinct features when compared to opsonin-mediated phagocytosis.
Collapse
Affiliation(s)
- Timothy H Sulahian
- Harvard School of Public Health, Molecular and Integrative Physiological Sciences Program, 655 Huntington Ave, Building II, 2nd Floor, Boston, MA 02115, USA.
| | | | | | | | | |
Collapse
|
17
|
Walter TN, Dunphy GB, Mandato CA. Steinernema carpocapsae DD136: metabolites limit the non-self adhesion responses of haemocytes of two lepidopteran larvae, Galleria mellonella (F. Pyralidae) and Malacosoma disstria (F. Lasiocampidae). Exp Parasitol 2008; 120:161-74. [PMID: 18656470 DOI: 10.1016/j.exppara.2008.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 06/27/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
Abstract
Live adult and juvenile entomopathogenic Steinernema carpocapsae DD136 (P. Nematoda) were not subjected to adhesion by haemocytes of lepidopteran insect larvae of Galleria mellonella or Malacosoma disstriain vitro or in vivo. In vitro freeze-killed nematodes exhibited haemocyte attachment, the intensity increasing with time. Accumulation of haemocytes on the dead nematodes was associated with host phenoloxidase activity; live nematodes and their exudates did not activate the enzyme whereas dead nematodes but not their exudate did activate phenoloxidase. Live-nematode exudate inhibited granular cell and some plasmatocyte adhesion to slides, increased granular cell but not plasmatocyte dissociation from preformed haemocyte monolayers and in vivo elevated total haemocyte counts and changed the floating haemocyte types while impairing bacterial removal from the haemolymph. Dead-nematode exudate did not affect these parameters thus immunosuppressant activity by live nematodes may represent the release of inhibitors not associated with their cuticle. The third stage juveniles released the inhibitors.
Collapse
Affiliation(s)
- Tita N Walter
- Department of Natural Resource Sciences, Macdonald Campus, McGill University, 21, 111 Lakeshore Road, Ste Anne de Bellevue, Que., Canada H9X 3V9
| | | | | |
Collapse
|
18
|
Dunphy GB, Chen G, Webster JM. The antioxidants dimethylsulfoxide and dimethylthiourea affect the immediate adhesion responses of larval haemocytes from 3 lepidopteran insect species. Can J Microbiol 2008; 53:1330-47. [PMID: 18059566 DOI: 10.1139/w07-096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Antioxidants, dimethylsulfoxide (DMSO) and dimethylthiourea (DMTU), at concentrations not affecting the viability of blood cells (haemocytes) from the larval stage of 3 lepidopteran insects - Galleria mellonella, Lymantria dispar, and Malacosoma disstria - differed in their influence on the innate binding of haemocytes to glass, bacteria to haemocytes, and on humoral responses to alien materials. In vitro DMSO had little effect, whereas DMTU substantially impaired the adhesion of the haemocyte types, the plasmatocytes and granular cells, to slides as well as the attachment of Bacillus subtilis to these haemocytes. Although both antioxidants increased lysozyme and phenoloxidase activities, there was no correlation of enzyme activity and haemocyte adhesion responses, possibly reflecting sequestered radicals. Nitric oxide and hydroxyl radicals offset the DMTU effect. In the absence of antioxidants, inactivate protein kinases A (PKA) and C (PKC) enhanced haemocyte aggregation. In general, DMSO, as opposed to DMTU, did not alter the effects of PKA and PKC activators and inhibitors on haemocyte aggregation or of PKC and PKA activities. High concentrations of DMSO and all levels of DMTU, although inhibiting PKA and PKC, inhibited haemocyte adhesion to slides. Comparable results occurred for DMTU-treated haemocytes incubated with B. subtilis. In vivo DMSO, unlike DMTU, did not impair plasmatocyte or granular cell responses to foreign materials, including bacterial removal from the haemolymph and nodulation.
Collapse
Affiliation(s)
- Gary B Dunphy
- Department of Natural Resource Sciences, Macdonald Campus, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte Anne de Bellevue, QC H9X 3V9, Canada.
| | | | | |
Collapse
|
19
|
Elk-1 is a novel protein-binding partner for FAK, regulating phagocytosis in medfly hemocytes. J Cell Biochem 2008; 103:1895-911. [DOI: 10.1002/jcb.21580] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
20
|
Sideri M, Tsakas S, Markoutsa E, Lampropoulou M, Marmaras VJ. Innate immunity in insects: surface-associated dopa decarboxylase-dependent pathways regulate phagocytosis, nodulation and melanization in medfly haemocytes. Immunology 2007; 123:528-37. [PMID: 17983437 DOI: 10.1111/j.1365-2567.2007.02722.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Phagocytosis, melanization and nodulation in insects depend on phenoloxidase (PO) activity. In this report, we demonstrated that these three processes appear to be also dependent on dopa decarboxylase (Ddc) activity. Using flow cytometry, RNA interference, immunoprecipitation and immunofluorescence, we demonstrated the constitutive expression of Ddc and its strong association with the haemocyte surface, in the medfly Ceratitis capitata. In addition, we showed that Escherichia coli phagocytosis is markedly blocked by small interfering RNA (siRNA) for Ddc, antibodies against Ddc, as well as by inhibitors of Ddc activity, namely carbidopa and benzerazide, convincingly revealing the involvement of Ddc activity in phagocytosis. By contrast, latex beads and lipopolysaccharide (LPS) did not require Ddc activity for their uptake. It was also shown that nodulation and melanization processes depend on Ddc activation, because antibodies against Ddc and inhibitors of Ddc activity prevent haemocyte aggregation and melanization in the presence of excess E. coli. Therefore, phagocytosis, melanization and nodulation depend on haemocyte-surface-associated PO and Ddc. These three unrelated mechanisms are based on tyrosine metabolism and share a number of substrates and enzymes; however, they appear to be distinct. Phagocytosis and nodulation depend on dopamine-derived metabolite(s), not including the eumelanin pathway, whereas melanization depends exclusively on the eumelanin pathway. It must also be underlined that melanization is not a prerequisite for phagocytosis or nodulation. To our knowledge, the involvement of Ddc, as well as dopa and its metabolites, are novel aspects in the phagocytosis of medfly haemocytes.
Collapse
Affiliation(s)
- Maria Sideri
- Laboratory of Biology, Department of Biology, University of Patras, Patras, Greece
| | | | | | | | | |
Collapse
|
21
|
Chen-Chih Wu R, Shaio MF, Cho WL. A p38 MAP kinase regulates the expression of the Aedes aegypti defensin gene in mosquito cells. INSECT MOLECULAR BIOLOGY 2007; 16:389-99. [PMID: 17466055 DOI: 10.1111/j.1365-2583.2007.00734.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
An Aedes aegypti p38 (Aap38) mitogen-activated protein kinase was isolated and characterized in this study. The 1761 bp long full-length Aap38 cDNA encodes an open reading frame of 358 amino acids, exhibiting characteristics of Thr/Tyr dual kinase specificities. We showed that bacteria activate both the kinase activity of Aap38 and the expression of the Aedes aegypti defensin A (AaDefA) gene, which is inhibited by a p38 kinase inhibitor SB203580 and dsRNA interference of Aap38. A similar result was obtained by a reporter construct containing the AaDefA regulatory region linked to Ds-Red. The lipopolysaccharide-activated reporter gene was inhibited by SB203580. In addition, Aap38 translocated to the nucleus after lipopolysaccharide induction. Our findings suggest that the p38 protein kinase pathway is involved in the antibacterial peptide synthesis in mosquitoes.
Collapse
Affiliation(s)
- R Chen-Chih Wu
- Institute of Tropical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | | | | |
Collapse
|
22
|
Mamali I, Tatari MN, Micheva I, Lampropoulou M, Marmaras VJ. Apoptosis in medfly hemocytes is regulated during pupariation through FAK, Src, ERK, PI-3K p85a, and Akt survival signaling. J Cell Biochem 2007; 101:331-47. [PMID: 17177294 DOI: 10.1002/jcb.21175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Focal adhesion kinase (FAK) and its downstream signaling targets are implicated in the process of apoptosis induced by external stimuli, in several mammalian systems. In this report, we demonstrate, that medfly (Ceratitis capitata) hemocytes do undergo apoptosis during larval development. In particular, we show using Western blot, ELISA and flow cytometry analysis, that FAK expression silencing in transfected by FAK double-stranded RNA (dsRNA) hemocytes, enhances twofold hemocyte apoptosis, by signaling through Src, MEK/ERK, and PI-3K/Akt signaling pathways. FAK expression silencing, in response to FAK dsRNA treatment, blocks partially the phosphorylation of its downstream targets. Pre-incubation of hemocytes, with specific inhibitors of FAK downstream signaling molecules, demonstrated that all these inhibitors reduced hemocyte viability and enhanced the magnitude of apoptosis about threefold. This data suggest that these pathways contribute to hemocyte survival and/or death during development. The expression and phosphorylation of FAK, Src, PI-3K p85a, Akt, and ERK signaling molecules appear to be dependent upon developmental stages. The expression and phosphorylation of the above signaling molecules, in annexin-positive and annexin-negative hemocytes is also distinct. The maximum expression and phosphorylation of FAK, Src, PI-3K p85a, Akt, and ERK appeared in annexin-positive hemocytes, in both early and late apoptotic hemocytes. The novel aspect of this report is based on the fact that hemocytes attempt to suppress apoptosis, by increasing the expression/phosphorylation of FAK and, hence its downstream targets signaling molecules Src, ERK, PI-3K p85a, and Akt. Evidently, the basic survival pathways among insects and mammals appear to remain unchanged, during evolution.
Collapse
Affiliation(s)
- Irene Mamali
- Department of Biology, University of Patras, Patras, Greece
| | | | | | | | | |
Collapse
|
23
|
Lamprou I, Mamali I, Dallas K, Fertakis V, Lampropoulou M, Marmaras VJ. Distinct signalling pathways promote phagocytosis of bacteria, latex beads and lipopolysaccharide in medfly haemocytes. Immunology 2007; 121:314-27. [PMID: 17376199 PMCID: PMC2265961 DOI: 10.1111/j.1365-2567.2007.02576.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
In insects, phagocytosis is an important innate immune response against pathogens and parasites, and several signal transduction pathways regulate this process. The focal adhesion kinase (FAK)/Src and mitogen activated protein kinase (MAPK) pathways are of central importance because their activation upon pathogen challenge regulates phagocytosis via haemocyte secretion and activation of the prophenoloxidase (proPO) cascade. The goal of this study was to explore further the mechanisms underlying the process of phagocytosis. In particular, in this report, we used flow cytometry, RNA interference, enzyme-linked immunosorbent assay, Western blot and immunoprecipitation analysis to demonstrate that (1) phagocytosis of bacteria (both Gram-negative and Gram-positive) is dependent on RGD-binding receptors, FAK/Src and MAPKs, (2) latex bead phagocytosis is RGD-binding-receptor-independent and dependent on FAK/Src and MAPKs, (3) lipopolysaccharide internalization is RGD-binding-receptor-independent and FAK/Src-independent but MAPK-dependent and (4) in unchallenged haemocytes in suspension, FAK, Src and extracellular signal-regulated kinase (ERK) signalling molecules participating in phagocytosis show both a functional and a physical association. Overall, this study has furthered knowledge of FAK/Src and MAPK signalling pathways in insect haemocyte immunity and has demonstrated that distinct signalling pathways regulate the phagocytic activity of biotic and abiotic components in insect haemocytes. Evidently, the basic phagocytic signalling pathways among insects and mammals appear to have remained unchanged during evolution.
Collapse
Affiliation(s)
- Irene Lamprou
- Department of Biology, University of Patras, Patras, Greece
| | | | | | | | | | | |
Collapse
|
24
|
Nishiyama A, Tsuji S, Yamashita M, Henriksen RA, Myrvik QN, Shibata Y. Phagocytosis of N-acetyl-D-glucosamine particles, a Th1 adjuvant, by RAW 264.7 cells results in MAPK activation and TNF-alpha, but not IL-10, production. Cell Immunol 2006; 239:103-12. [PMID: 16781693 DOI: 10.1016/j.cellimm.2006.04.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Revised: 04/17/2006] [Accepted: 04/28/2006] [Indexed: 10/24/2022]
Abstract
A practical and highly effective Th1 adjuvant should induce Th1 cytokines (IL-12, IL-18, and TNF-alpha) but not the Th2 cytokine IL-10, an inhibitor of Th1 responses. In this study, phagocytosis of N-acetyl-d-glucosamine polymer (chitin) particles by RAW 264.7 cells, a murine macrophage-like cell line, resulted in phosphorylation of MAPK (p38, Erk 1/2, and JNK), and production of relatively high levels of TNF-alpha and COX-2 with increased PGE(2) release. Similar results were observed in response to oligonucleotides with CpG motifs, mycobacterial components and endotoxin. However, these bacterial components also induced a large amount of IL-10. Chitin particles, in contrast, failed to induce detectable levels of IL-10, although the production of high levels of PGE(2) and TNF-alpha and the activation of MAPK's are potentially positive signals for IL-10 production. Thus, our results indicate that chitin particles act as a unique Th1 adjuvant for macrophages without inducing increased production of IL-10.
Collapse
Affiliation(s)
- Akihito Nishiyama
- Department of Biomedical Sciences, Florida Atlantic University, Boca Raton, FL 33431-0991, USA.
| | | | | | | | | | | |
Collapse
|
25
|
Jiravanichpaisal P, Lee BL, Söderhäll K. Cell-mediated immunity in arthropods: Hematopoiesis, coagulation, melanization and opsonization. Immunobiology 2006; 211:213-36. [PMID: 16697916 DOI: 10.1016/j.imbio.2005.10.015] [Citation(s) in RCA: 517] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Accepted: 10/13/2005] [Indexed: 01/12/2023]
Abstract
The functions of hemocytes in innate immune response are reviewed with emphasized on their roles in coagulation, melanization and opsonization. Also the ways in which hemocytes are produced in and released from hematopoietic tissue are discussed.
Collapse
Affiliation(s)
- Pikul Jiravanichpaisal
- Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden
| | | | | |
Collapse
|
26
|
Krishnan N, Hyrsl P, Simek V. Nitric oxide production by hemocytes of larva and pharate prepupa of Galleria mellonella in response to bacterial lipopolysaccharide: Cytoprotective or cytotoxic? Comp Biochem Physiol C Toxicol Pharmacol 2006; 142:103-10. [PMID: 16316786 DOI: 10.1016/j.cbpc.2005.10.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Revised: 10/29/2005] [Accepted: 10/30/2005] [Indexed: 01/02/2023]
Abstract
Nitric oxide production by the hemocytes of the last instar larvae and sessile pharate prepupa of Galleria mellonella (Lepidoptera: Pyralidae) was demonstrated in vitro in response to preparations of bacterial lipopolysaccharide (LPS) from Escherichia coli using the Griess reaction. Augmented, dose dependent nitric oxide production was observed in the pharate prepupal hemocytes compared with larval hemocytes. This was partially reversed in a dose dependent manner with S-methyl thiourea (SMT), a specific inhibitor of inducible nitric oxide synthase (iNOS). A decrease in NO production was also observed when non-selective inhibitors such as N(G)-nitro-L-arginine (L-NAME) and N-omega-nitro-L-arginine (L-NNA) were used, albeit the inhibition was not to the extent of SMT. Challenge with the entomopathogenic Gram-negative bacterium Photorhabdus asymbiotica also enhanced NO production by hemocytes of both stages. SMT, alone or in combination with P. asymbiotica significantly decreased levels of NO production. However, it was observed that phenoloxidase activity (a cascade for innate immune responses) was independent of NO production stimulation. NO donors, S-nitroso-N-acetyl-penicillamine (SNAP) and diethylenetriamine NO adduct (DETA/NO) at various concentrations (100-500 microM) resulted in the lysis of hemocytes dose dependently. The nitrite production in these cases was however similar to LPS stimulation (10 microg/mL) and 1.5-3 fold lower than those observed upon P. asymbiotica (2.5 x 10(7) cfu/mL) stimulation. Survival analysis (Kaplan-Meier) following injection of P. asymbiotica alone or in combination with SMT revealed that only 12.5% (median survival 25.5 h) of co-injected larvae of G. mellonella survived in comparison to 28.6% (median survival 29 h) survivors in P. asymbiotica alone-injected groups till the end of the study. In contrast, co-injected pharate prepupa survived longer (median survival 28 h) than the P. asymbiotica alone-injected individuals (median survival 24 h); however, both co-injected and P. asymbiotica-injected groups showed 100% mortality at the end of the study. Based on the above, we propose that although NO production is involved in cellular immune responses of this insect to bacterial infection it does not appear to be a part of the signalling pathway that initiates the prophenoloxidase (PPO) cascade, and the extended NO production/overproduction by pharate prepupal hemocytes could result in cytotoxic rather than cytoprotective effects compared with larval hemocytes.
Collapse
Affiliation(s)
- Natraj Krishnan
- Department of Physiology, Institute of Entomology, Academy of Sciences of the Czech Republic, Ceské Budejovice
| | | | | |
Collapse
|
27
|
Mavrouli MD, Tsakas S, Theodorou GL, Lampropoulou M, Marmaras VJ. MAP kinases mediate phagocytosis and melanization via prophenoloxidase activation in medfly hemocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1744:145-56. [PMID: 15921769 DOI: 10.1016/j.bbamcr.2005.04.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Revised: 04/22/2005] [Accepted: 04/25/2005] [Indexed: 11/16/2022]
Abstract
E. coli phagocytosis by medfly hemocytes, in contrast to mammalian macrophages, associates with E. coli-challenged hemocyte secretion by mitogen activating protein (MAP) kinases. In the present work, we examined whether this system links with the proteolytic activation of prophenoloxidase (proPO). ProPO and prophenoloxidase-activating proteinases (PAPs) were initially identified within freshly isolated medfly hemocytes. Moreover, flow cytometry and immunocytochemical analysis revealed the constitutive expression of proPO and its stable association with hemocyte surface. The expression level of hemocyte surface proPO is not affected by E. coli infection. In addition, flow cytometry analysis in freshly isolated hemocytes showed that E. coli phagocytosis is markedly blocked by antibodies against proPO or PAPs, as well as by several serine protease inhibitors, strongly supporting the involvement of proPO cascade in the phagocytosis process. Similarly, it was shown that melanization process depends on proPO activation. MAP kinases appeared to control both phagocytosis and melanization, since they regulate PAPs secretion, a prerequisite for the conversion of proPO to active PO. From this and previous studies, hemocytes appear to be central to immune response in medfly.
Collapse
Affiliation(s)
- Maria D Mavrouli
- Laboratory of Biology, Department of Biology, University of Patras, Greece
| | | | | | | | | |
Collapse
|