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Li S, Liu F, Kang Z, Li X, Lu Y, Li Q, Pang Y, Zheng F, Yin X. Cellular immune responses of the yellow peach moth, Conogethes punctiferalis (Lepidoptera: Crambidae), to the entomopathogenic fungus, Beauveria bassiana (Hypocreales: Cordycipitaceae). J Invertebr Pathol 2022; 194:107826. [PMID: 36075444 DOI: 10.1016/j.jip.2022.107826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 11/27/2022]
Abstract
The yellow peach moth (YPM), Conogethes punctiferalis, is a destructive insect pest of maize in eastern China and adapts to diverse environments, especially against pathogens. In insects, innate immunity comprising both humoral and cellular defense responses, is the primary defense against invading microbial pathogens. In this study, we identified five types of circulating hemocytes from the hemolymph of YPM larvae and analyzed their alterations and functions in immune responses to the infection of Beauveria bassiana, an entomopathogenic fungus infesting many lepidopteran species. The identified hemocytes included prohemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids. Significant decreases of total and differential hemocyte counts were recorded over time in larvae, after they were injected with B. bassiana conidia. Additionally, hemocyte-mediated phagocytosis and nodulation were initiated in the hemolymph of larvae from the B. bassiana conidia challenge. The introduction of DEAE-Sepharose Fast Flow beads stained with Congo red also induced a strong encapsulation response in the larval hemolymph. Our observations unravel the occurrence of phagocytosis, nodulation and encapsulation in the hemocoel of YPM larvae to fight against the fungal infection, and offer the first insight into the YPM immune system.
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Affiliation(s)
- Shaohua Li
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Fanghua Liu
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China; College of Life Science, Hebei University, Baoding 071002, China
| | - Zhiwei Kang
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China; College of Life Science, Hebei University, Baoding 071002, China
| | - Xiangdong Li
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Yang Lu
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun 130033, China
| | - Qiyun Li
- Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Changchun 130033, China
| | - Yunshun Pang
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Fangqiang Zheng
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China.
| | - Xiangchu Yin
- College of Plant Protection, Shandong Agricultural University, Taian 271018, China; College of Life Science, Hebei University, Baoding 071002, China.
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2
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Gwokyalya R, Herren JK, Weldon CW, Khamis FM, Ndlela S, Mohamed SA. Differential immune responses in new and old fruit fly-parasitoid associations: Implications for their management. Front Physiol 2022; 13:945370. [PMID: 36091407 PMCID: PMC9458847 DOI: 10.3389/fphys.2022.945370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/22/2022] [Indexed: 11/24/2022] Open
Abstract
The oriental fruit fly, Bactrocera dorsalis (Hendel), and marula fruit fly, Ceratitis cosyra (Walker), are major fruit-infesting tephritids across sub-Saharan Africa. Biological control of these pests using parasitic wasps has been widely adopted but with varying levels of success. Most studies investigating host-parasitoid models have focused on functional and evolutionary aspects leaving a knowledge gap about the physiological mechanisms underpinning the efficacy of parasitoids as biocontrol agents of tephritids. To better understand these physiological mechanisms, we investigated changes in the cellular immune responses of C. cosyra and B. dorsalis when exposed to the parasitic wasps, Diachasmimorpha longicaudata (Ashmaed) and Psyttalia cosyrae (Wilkinson). We found that B. dorsalis was more resistant to parasitisation, had a higher hemocyte count, and encapsulated more parasitoid eggs compared to C. cosyra, achieving up to 100% encapsulation when exposed to P. cosyrae. Exposing B. dorsalis to either parasitoid species induced the formation of a rare cell type, the giant multinucleated hemocyte, which was not observed in C. cosyra. Furthermore, compared to P. cosyrae-parasitized larvae, those of both host species parasitized by D. longicaudata had lower encapsulation rates, hemocyte counts and spreading abilities and yielded a higher number of parasitoid progeny with the highest parasitoid emergence (72.13%) recorded in C. cosyra. These results demonstrate that cellular immune responses are central to host-parasitoid interaction in tephritid fruit flies and further suggest that D. longicaudata presents greater potential as a biocontrol agent of B. dorsalis and C. cosyra in horticultural cropping systems.
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Affiliation(s)
- Rehemah Gwokyalya
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
- *Correspondence: Rehemah Gwokyalya, , ; Samira Abuelgasim Mohamed,
| | - Jeremy K. Herren
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Christopher W. Weldon
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Fathiya M. Khamis
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Shepard Ndlela
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Samira Abuelgasim Mohamed
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- *Correspondence: Rehemah Gwokyalya, , ; Samira Abuelgasim Mohamed,
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3
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von Bredow YM, Müller A, Popp PF, Iliasov D, von Bredow CR. Characterization and mode of action analysis of black soldier fly (Hermetia illucens) larva-derived hemocytes. INSECT SCIENCE 2022; 29:1071-1095. [PMID: 34687131 DOI: 10.1111/1744-7917.12977] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 10/01/2021] [Accepted: 10/04/2021] [Indexed: 06/13/2023]
Abstract
With the growing importance of the black soldier fly (Hermetia illucens) for both sustainable food production and waste management as well as for science, a great demand of understanding its immune system arises. Here, we present the first description of the circulating larval hemocytes with special emphasis on uptake of microorganisms and distinguishing hemocyte types. With histological, zymographic, and cytometric methods and with a set of hemocyte binding lectins and antibodies, the hemocytes of H. illucens are identified as plasmatocytes, crystal cells, and putative prohemocytes. Total hemocyte counts (THC) are determined, and methods for THC determination are compared. Approximately 1100 hemocytes per microliter hemolymph are present in naive animals, while hemocyte density decreases dramatically shortly after wounding, indicating a role of hemocytes in response to wounding (and immune response in general). The determination of the relative abundance of each hemocyte type (differential hemocyte count, DHC) revealed that plasmatocytes are highly abundant, whereas prohemocytes and crystal cells make up only a small percentage of the circulating cells. Plasmatocytes are not only the most abundant but also the professional phagocytes in H. illucens. They rapidly engulf and take up bacteria both in vivo and in vitro, indicating a very potent cellular defense against invading pathogens. Larger bioparticles such as yeasts are also removed from circulation by phagocytosis, but slower than bacteria. This is the first analysis of the potent cellular immune response in the black soldier fly, and a first toolbox that helps to identify hemocyte (types) is presented.
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Affiliation(s)
- Yvette M von Bredow
- Justus-Liebig-Universität Gießen, Institut für Allgemeine Zoologie und Entwicklungsbiologie, Zelluläre Erkennungs- und Abwehrprozesse, Gießen, Germany
| | - Ariane Müller
- Technische Universität Dresden, Fakultät Biologie, Institut für Zoologie, Dresden, Germany
| | - Philipp F Popp
- Technische Universität Dresden, Fakultät Biologie, Institut für Mikrobiologie, Dresden, Germany
- Present address: Philipp F. Popp, Institute for Biology-Bacterial Physiology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Denis Iliasov
- Technische Universität Dresden, Fakultät Biologie, Institut für Mikrobiologie, Dresden, Germany
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4
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Moure UAE, Tan T, Sha L, Lu X, Shao Z, Yang G, Wang Y, Cui H. Advances in the Immune Regulatory Role of Non-Coding RNAs (miRNAs and lncRNAs) in Insect-Pathogen Interactions. Front Immunol 2022; 13:856457. [PMID: 35464405 PMCID: PMC9020863 DOI: 10.3389/fimmu.2022.856457] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/10/2022] [Indexed: 11/30/2022] Open
Abstract
Insects are by far the most abundant and diverse living organisms on earth and are frequently prone to microbial attacks. In other to counteract and overcome microbial invasions, insects have in an evolutionary way conserved and developed immune defense mechanisms such as Toll, immune deficiency (Imd), and JAK/STAT signaling pathways leading to the expression of antimicrobial peptides. These pathways have accessory immune effector mechanisms, such as phagocytosis, encapsulation, melanization, nodulation, RNA interference (RNAi), lysis, autophagy, and apoptosis. However, pathogens evolved strategies that circumvent host immune response following infections, which may have helped insects further sophisticate their immune response mechanisms. The involvement of ncRNAs in insect immunity is undeniable, and several excellent studies or reviews have investigated and described their roles in various insects. However, the functional analyses of ncRNAs in insects upon pathogen attacks are not exhaustive as novel ncRNAs are being increasingly discovered in those organisms. This article gives an overview of the main insect signaling pathways and effector mechanisms activated by pathogen invaders and summarizes the latest findings of the immune modulation role of both insect- and pathogen-encoded ncRNAs, especially miRNAs and lncRNAs during insect–pathogen crosstalk.
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Affiliation(s)
- Ulrich Aymard Ekomi Moure
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China.,Medical Research Institute, Southwest University, Chongqing, China
| | - Tingshan Tan
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Lin Sha
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Xiaoqin Lu
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Zhi Shao
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Guang Yang
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Yi Wang
- Affiliated Hospital of Southwest University, the Ninth People's Hospital of Chongqing, Chongqing, China.,Department of Gastrointestinal Surgery, the Ninth People's Hospital of Chongqing, Chongqing, China
| | - Hongjuan Cui
- Medical Research Institute, Southwest University, Chongqing, China.,State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture, Southwest University, Chongqing, China
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5
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Kong M, Zuo H, Zhu F, Hu Z, Chen L, Yang Y, Lv P, Yao Q, Chen K. The interaction between baculoviruses and their insect hosts. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 83:114-123. [PMID: 29408049 DOI: 10.1016/j.dci.2018.01.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 06/07/2023]
Abstract
Baculoviruses are double-stranded circular DNA viruses that infect arthropods via the midgut. Because of their superiority as eukaryotic expression systems and their importance as biopesticides, extensive research on the functions of baculovirus genes as well as on the host response to baculovirus infection has been carried out, including transcriptomic and proteomic analyses of the midgut. The morphological and cellular changes caused by baculovirus infection are also important to better understand the infection pathway. Thanks to these previous studies, we now have a clearer picture of the mechanisms of action of the virus and of host immunity. In this paper, we systematically reviewed studies on the interaction between baculoviruses and their insect hosts. By better understanding these interactions, baculoviruses can be developed for use as more efficient biopesticides to improve agricultural development in the future.
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Affiliation(s)
- Ming Kong
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Huan Zuo
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Feifei Zhu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Zhaoyang Hu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Liang Chen
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yanhua Yang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Peng Lv
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Qin Yao
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Keping Chen
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
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6
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Hillyer JF. Insect immunology and hematopoiesis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 58:102-18. [PMID: 26695127 PMCID: PMC4775421 DOI: 10.1016/j.dci.2015.12.006] [Citation(s) in RCA: 280] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 12/08/2015] [Accepted: 12/10/2015] [Indexed: 05/08/2023]
Abstract
Insects combat infection by mounting powerful immune responses that are mediated by hemocytes, the fat body, the midgut, the salivary glands and other tissues. Foreign organisms that have entered the body of an insect are recognized by the immune system when pathogen-associated molecular patterns bind host-derived pattern recognition receptors. This, in turn, activates immune signaling pathways that amplify the immune response, induce the production of factors with antimicrobial activity, and activate effector pathways. Among the immune signaling pathways are the Toll, Imd, Jak/Stat, JNK, and insulin pathways. Activation of these and other pathways leads to pathogen killing via phagocytosis, melanization, cellular encapsulation, nodulation, lysis, RNAi-mediated virus destruction, autophagy and apoptosis. This review details these and other aspects of immunity in insects, and discusses how the immune and circulatory systems have co-adapted to combat infection, how hemocyte replication and differentiation takes place (hematopoiesis), how an infection prepares an insect for a subsequent infection (immune priming), how environmental factors such as temperature and the age of the insect impact the immune response, and how social immunity protects entire groups. Finally, this review highlights some underexplored areas in the field of insect immunobiology.
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Affiliation(s)
- Julián F Hillyer
- Department of Biological Sciences, Vanderbilt University, VU Station B 35-1634, Nashville, TN 37235, USA.
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7
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Insect Immunity to Entomopathogenic Nematodes and Their Mutualistic Bacteria. Curr Top Microbiol Immunol 2016; 402:123-156. [PMID: 27995342 DOI: 10.1007/82_2016_52] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Entomopathogenic nematodes are important organisms for the biological control of insect pests and excellent models for dissecting the molecular basis of the insect immune response against both the nematode parasites and their mutualistic bacteria. Previous research involving the use of various insects has found distinct differences in the number and nature of immune mechanisms that are activated in response to entomopathogenic nematode parasites containing or lacking their associated bacteria. Recent studies using model insects have started to reveal the identity of certain molecules with potential anti-nematode or antibacterial activity as well as the molecular components that nematodes and their bacteria employ to evade or defeat the insect immune system. Identification and characterization of the genes that regulate the insect immune response to nematode-bacteria complexes will contribute significantly to the development of improved practices to control insects of agricultural and medical importance, and potentially nematode parasites that infect mammals, perhaps even humans.
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8
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Ardisson-Araujo DMP, Rohrmann GF, Ribeiro BM, Clem RJ. Functional characterization of hesp018, a baculovirus-encoded serpin gene. J Gen Virol 2015; 96:1150-1160. [PMID: 25573886 DOI: 10.1099/vir.0.000041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/05/2015] [Indexed: 12/21/2022] Open
Abstract
The serpin family of serine proteinase inhibitors plays key roles in a variety of biochemical pathways. In insects, one of the important functions carried out by serpins is regulation of the phenoloxidase (PO) cascade - a pathway that produces melanin and other compounds that are important in insect humoral immunity. Recent sequencing of the baculovirus Hemileuca sp. nucleopolyhedrovirus (HespNPV) genome revealed the presence of a gene, hesp018, with homology to insect serpins. To our knowledge, hesp018 is the first viral serpin homologue to be characterized outside of the chordopoxviruses. The Hesp018 protein was found to be a functional serpin with inhibitory activity against a subset of serine proteinases. Hesp018 also inhibited PO activation when mixed with lepidopteran haemolymph. The Hesp018 protein was secreted when expressed in lepidopteran cells and a baculovirus expressing Hesp018 exhibited accelerated production of viral progeny during in vitro infection. Expression of Hesp018 also reduced caspase activity induced by baculovirus infection, but caused increased cathepsin activity. In infected insect larvae, expression of Hesp018 resulted in faster larval melanization, consistent with increased activity of viral cathepsin. Finally, expression of Hesp018 increased the virulence of a prototype baculovirus by fourfold in orally infected neonate Trichoplusia ni larvae. Based on our observations, we hypothesize that hesp018 may have been retained in HespNPV due to its ability to inhibit the activity of select host proteinases, possibly including proteinases involved in the PO response, during infection of host insects.
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Affiliation(s)
- Daniel M P Ardisson-Araujo
- Department of Cell Biology, University of Brasilia, Brasilia, DF, Brazil.,Division of Biology, Kansas State University, Manhattan, KS, USA
| | - George F Rohrmann
- Department of Microbiology, Oregon State University, Corvallis, OR, USA
| | - Bergmann M Ribeiro
- Department of Cell Biology, University of Brasilia, Brasilia, DF, Brazil
| | - Rollie J Clem
- Division of Biology, Kansas State University, Manhattan, KS, USA
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9
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Kato Y, Yoshida T, Miura K, Tanaka T, Nakamatsu Y, Ochiai M. A novel type of hemocytes localizing melanization with high-spreading behavior in Mythimna separata. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2014; 86:220-239. [PMID: 24986040 DOI: 10.1002/arch.21173] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Lepidopteran larvae show a cellular response to invading foreign substances that are larger than hemocytes, for example, parasitoid eggs or larvae. This response is called hemocyte encapsulation and is often accompanied by phenoloxidase (PO)-catalyzed melanization. In the present study, we artificially transplanted endoparasitoid larvae and small glass fragments into the hemocoel of the common armyworm, Mythimna separata. We observed that the host larva showed a cellular response and that, 2-4 h after transplantation, melanin formation was spatially confined to the surface of the encapsulated substances. We further noted that specific morphological hemocytes surrounded by melanin formation became attached to the surface of the foreign substances. We designated these hemocytes hyperspread cells (HSCs) on the basis of their specific characteristics and circumferential spread. We confirmed the occurrence of prophenoloxidase (PPO)/phenoloxidase (PO) on the periphery of the HSCs and in the substance secreted around the HSCs by using anti-PPO antibody. We were unable to detect PPO-mRNA in HSCs by using in situ hybridization, although we showed that oenocytoids contained PPO-mRNA and PPO protein. We used light microscopy and scanning electron microscopy to discriminate five main types of circulating M. separata hemocytes. We observed that HSCs differed from plasmatocytes, but spread out well. Further, during the encapsulation process, HSCs appeared to provide a localized melanization spot on the surface of foreign invaders.
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Affiliation(s)
- Yoshiaki Kato
- Laboratory of Applied Entomology, Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
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10
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Muñoz FA, Franco-Noguez SY, Gonzalez-Ballesteros E, Negrete-Philippe AC, Flores-Romo L. Characterisation of the green turtle’s leukocyte subpopulations by flow cytometry and evaluation of their phagocytic activity. Vet Res Commun 2014; 38:123-8. [DOI: 10.1007/s11259-014-9595-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2014] [Indexed: 11/30/2022]
Affiliation(s)
- F A Muñoz
- Facultad de Agronomía y Veterinaria, Universidad Autónoma de San Luis Potosí, Carretera San Luis-Matehuala km 14.5, Soledad de Graciano Sánchez, C.P.78433, San Luis Potosí, México,
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11
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Abstract
Lepidopteran insects provide important model systems for innate immunity of insects, particularly for cell biology of hemocytes and biochemical analyses of plasma proteins. Caterpillars are also among the most serious agricultural pests, and understanding of their immune systems has potential practical significance. An early response to infection in lepidopteran larvae is the activation of hemocyte adhesion, leading to phagocytosis, nodule formation, or encapsulation. Plasmatocytes and granular cells are the hemocyte types involved in these responses. Infectious microorganisms are recognized by binding of hemolymph plasma proteins to microbial surface components. This "pattern recognition" triggers phagocytosis and nodule formation, activation of prophenoloxidase and melanization and the synthesis of antimicrobial proteins that are secreted into the hemolymph. Many hemolymph proteins that function in such innate immune responses of insects were first discovered in lepidopterans. Microbial proteinases and nucleic acids released from lysed host cells may also activate lepidopteran immune responses. Hemolymph antimicrobial peptides and proteins can reach high concentrations and may have activity against a broad spectrum of microorganisms, contributing significantly to clearing of infections. Serine proteinase cascade pathways triggered by microbial components interacting with pattern recognition proteins stimulate activation of the cytokine Spätzle, which initiates the Toll pathway for expression of antimicrobial peptides. A proteinase cascade also results inproteolytic activation of phenoloxidase and production of melanin coatings that trap and kill parasites and pathogens. The proteinases in hemolymph are regulated by specific inhibitors, including members of the serpin superfamily. New developments in lepidopteran functional genomics should lead to much more complete understanding of the immune systems of this insect group.
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12
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Senior NJ, Bagnall MC, Champion OL, Reynolds SE, La Ragione RM, Woodward MJ, Salguero FJ, Titball RW. Galleria mellonella as an infection model for Campylobacter jejuni virulence. J Med Microbiol 2011; 60:661-669. [PMID: 21233296 DOI: 10.1099/jmm.0.026658-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Larvae of Galleria mellonella (Greater Wax Moth) have been shown to be susceptible to Campylobacter jejuni infection and our study characterizes this infection model. Following infection with C. jejuni human isolates, bacteria were visible in the haemocoel and gut of challenged larvae, and there was extensive damage to the gut. Bacteria were found in the extracellular and cell-associated fraction in the haemocoel, and it was shown that C. jejuni can survive in insect cells. Finally, we have used the model to screen a further 67 C. jejuni isolates belonging to different MLST types. Isolates belonging to ST257 were the most virulent in the Galleria model, whereas those belonging to ST21 were the least virulent.
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Affiliation(s)
- Nicola J Senior
- School of BioSciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK
| | - Mary C Bagnall
- Veterinary Laboratories Agency, Woodham Lane, Addlestone, UK
| | - Olivia L Champion
- School of BioSciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK
| | - Stuart E Reynolds
- Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Roberto M La Ragione
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.,Veterinary Laboratories Agency, Woodham Lane, Addlestone, UK
| | | | | | - Richard W Titball
- School of BioSciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK
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13
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Zibaee A, Bandani AR, Talaei-Hassanlouei R, Malagoli D. Cellular immune reactions of the sunn pest, Eurygaster integriceps, to the entomopathogenic fungus, Beauveria bassiana and its secondary metabolites. JOURNAL OF INSECT SCIENCE (ONLINE) 2011; 11:138. [PMID: 22233481 PMCID: PMC3391913 DOI: 10.1673/031.011.13801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 04/17/2011] [Indexed: 05/26/2023]
Abstract
In this study, five morphological types of circulating hemocytes were recognized in the hemolymph of the adult sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), namely prohemocytes, plasmatocytes, granulocytes, adipohemocytes, and oenocytoids. The effects of the secondary metabolites of the entomopathogenic fungus Beauveria bassiana on cellular immune defenses of Eurygaster integriceps were investigated. The results showed that the fungal secondary metabolites inhibited phagocytic activity of E. integriceps hemocytes and hampered nodule formation. A reduction of phenoloxidase activity was also observed. The data suggest that B. bassiana produce secondary metabolites that disable several immune mechanisms allowing the fungus to overcome and then kill its host. This characteristic makes B. bassiana a promising model for biological control of insect pests such as E. integriceps.
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Affiliation(s)
- Arash Zibaee
- Department of Plant Protection, College of Agriculture, University of Guilan, Rasht 41635-1314, Iran
| | - Ali Reza Bandani
- Department of Plant Protection, College of Agriculture and Natural Resources, University of Tehran, Karaj 31584,
Iran
| | - Reza Talaei-Hassanlouei
- Department of Plant Protection, College of Agriculture and Natural Resources, University of Tehran, Karaj 31584,
Iran
| | - Davide Malagoli
- Department of Biology, University of Modena and Reggio Emilia, Via Campi 213/D, 41125, Modena, Italy
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14
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Abstract
Photorhabdus is a member of the family Enterobacteriaceae that lives in a mutualistic association with a Heterorhabditis nematode worm. The nematode worm burrows into insect prey and regurgitates Photorhabdus, which goes on to kill the insect. The nematode feeds off the growing bacteria until the insect tissues are exhausted, whereupon they reassociate and leave the cadaver in search of new prey. This highly efficient partnership has been used for many years as a biological crop protection agent. The dual nature of Photorhabdus as a pathogen and mutualist makes it a superb model for understanding these apparently exclusive activities. Furthermore, recently identified clinical isolates of Photorhabdus are helping us to understand how human pathogens can emerge from the enormous reservoir of invertebrate pathogens in the environment. As Photorhabdus has never been found outside a host animal, its niche represents an entirely biotic landscape. In this review we discuss what molecular adaptations allow this bacterium to complete this fascinating and complex life cycle.
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Affiliation(s)
- Nick R Waterfield
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, United Kingdom.
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Roditakis E, Couzin ID, Franks NR, Charnley AK. Effects of Lecanicillium longisporum infection on the behaviour of the green peach aphid Myzus persicae. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:128-36. [PMID: 17942112 DOI: 10.1016/j.jinsphys.2007.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Revised: 08/14/2007] [Accepted: 08/20/2007] [Indexed: 05/10/2023]
Abstract
The effects of the entomopathogenic fungus Lecanicillium longisporum (Zimmerman) Zare & Gams on three parameters of behaviour (feeding, reproduction and movement) of the green peach aphid Myzus persicae (Homoptera: Aphididae) were investigated in the laboratory. Visual analysis of video tapes established that honeydew excretion events of mycosed aphids gradually declined from 2 d post inoculation and reproduction rate was significantly reduced 2 d prior to death (which occurred on day 6); both parameters were stable in controls over the same period. A detailed comparison was made between mobility of aphids during infection with two isolates of L. longisporum, using image analysis of video recordings. Both isolates caused an increase in activity at the beginning of mycosis (during fungal germination and cuticle invasion) though the intensity and the duration of this behaviour varied with the isolate. The possibility that increased movement in early mycosis helps disseminate disease is discussed in the light of the observation that saprophytic surface growth occurs on living M. persicae as it does in at least some other Lecanicillium spp-insect interactions.
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Affiliation(s)
- Emmanouil Roditakis
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
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16
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Eleftherianos I, Baldwin H, ffrench-Constant RH, Reynolds SE. Developmental modulation of immunity: changes within the feeding period of the fifth larval stage in the defence reactions of Manduca sexta to infection by Photorhabdus. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:309-318. [PMID: 18001766 DOI: 10.1016/j.jinsphys.2007.10.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 09/30/2007] [Accepted: 10/03/2007] [Indexed: 05/25/2023]
Abstract
In insect pathogen interactions, host developmental stage is among several factors that influence the induction of immune responses. Here, we show that the effectiveness of immune reactions to a pathogen can vary markedly within a single larval stage. Pre-wandering fifth-stage (day 5) larvae of the model lepidopteran insect Manduca sexta succumb faster to infection by the insect pathogenic bacterium Photorhabdus luminescens than newly ecdysed fifth-stage (day 0) caterpillars. The decrease in insect survival of the older larvae is associated with a reduction in both humoral and cellular defence reactions compared to less developed larvae. We present evidence that older fifth-stage larvae are less able to over-transcribe microbial pattern recognition protein and antibacterial effector genes in the fat body and hemocytes. Additionally, older larvae show reduced levels of phenoloxidase (PO) activity in the cell-free hemolymph plasma as well as a dramatic decrease in the number of circulating hemocytes, reduced ability to phagocytose bacteria and fewer melanotic nodules in the infected tissues. The decline in overall immune function of older fifth-stage larvae is reflected by higher bacterial growth in the hemolymph and increased colonization of Photorhabdus on the basal surface of the insect gut. We suggest that developmentally programmed variation in immune competence may have important implications for studies of ecological immunity.
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Affiliation(s)
- I Eleftherianos
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
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17
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de Winter P, Rayne RC, Coast GM. The effects of intracellular signalling pathway inhibitors on phagocytosis by haemocytes of Manduca sexta. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:975-82. [PMID: 17597143 DOI: 10.1016/j.jinsphys.2007.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 04/12/2007] [Accepted: 04/16/2007] [Indexed: 05/16/2023]
Abstract
The intracellular signalling pathways activated during phagocytosis by larval haemocytes of a lepidopteran, Manduca sexta, were investigated. Using fluorescein-labelled Escherichia coli as bioparticles, a fluorescence-based assay was used to quantify phagocytosis by haemocytes in monolayers in vitro, and the intracellular signalling pathways involved in phagocytosis were examined using inhibitors. Pathways known to be involved in phagocytosis by mammalian cells were selected for the study in haemocytes, and the amino acid sequences of human isoforms of the selected protein targets were used to conduct searches of two completed databases of insect proteins, those of Drosophila melanogaster and Anopheles gambiae and EST databases of moths Bombyx mori and M. sexta. Decreases in phagocytosis produced by pathway inhibitors indicated that tyrosine phosphorlylation phosphatidylinositol 3-kinase (PI3-kinase) and mitogen-activated protein kinase/extracellular-regulated kinase (ERK/MAPK) were required for internalisation of bacteria. Inhibition of Syk, a mammalian kinase, also decreased phagocytosis. JNK/SAPK did not seem to be involved in phagocytosis. The presence of protein phosphatases probably regulates phagocytosis at the intracellular level by dephosphorlyation of serine/threonine residues.
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Affiliation(s)
- Patricia de Winter
- School of Biological and Chemical Sciences, Birkbeck, University of London, London, UK.
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18
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Faraldo AC, Gregório EA, Lello E. Morphological and quantitative aspects of nodule formation in hemolymph of the blowfly Chrysomya megacephala (Fabricius, 1794). Exp Parasitol 2007; 118:372-7. [PMID: 18086470 DOI: 10.1016/j.exppara.2007.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 09/19/2007] [Accepted: 09/24/2007] [Indexed: 12/01/2022]
Abstract
Insects manifest effective immune responses that include both cellular and humoral components. Morphological and quantitative aspects of cellular and humoral cooperation during nodule formation in Chrysomya megacephala hemolymph against Saccharomyces cerevisae yeast cells were demonstrated for the first time. The analyses were performed in non-injected larvae (NIL), saline-injected larvae (SIL) and yeast-injected larvae (YIL). The hemolymph of injected groups was collected 0.5, 1, 2, 4, 12, 24, 36, or 48-h post-injection. Morphological aspects of YIL nodulation were investigated using transmission electron microscopy (TEM). Quantitative analyses consisted of total (THC) and differential hemocyte counts (DHC) in all the groups and total yeast count (TYC) in YIL, which were performed in an improved Neubauer chamber. Nodule formation was initiated at approximately 2-h post-injection. Twelve hours after the injection, TEM revealed the presence of an amorphous membrane, at the same time that circulating hemocyte number decreased significantly contrasting the increase of yeast number. Our results showed the ability of C. megacephala hemolymph to perform humoral encapsulation when hemocyte population is insufficient to eliminate the microorganisms, warranting consideration in future investigations on the relative roles played by cellular and humoral elements of innate immunity of this calliphorid.
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Affiliation(s)
- A C Faraldo
- Unidade Acadêmica de Garanhuns, Universidade Federal Rural de Pernambuco, 55292-901 Garanhuns, Pernambuco, Brazil.
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19
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Zhuang S, Kelo L, Nardi JB, Kanost MR. Neuroglian on hemocyte surfaces is involved in homophilic and heterophilic interactions of the innate immune system of Manduca sexta. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2007; 31:1159-67. [PMID: 17448535 DOI: 10.1016/j.dci.2007.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Revised: 02/16/2007] [Accepted: 03/02/2007] [Indexed: 05/15/2023]
Abstract
Neuroglian, a member of the L1 family of cell adhesion molecules (L1-CAMs), is expressed on surfaces of granular cells and a subset of large plasmatocytes of Manduca sexta that act as foci for hemocyte aggregation during the innate immune response. Neuroglian expressed on surfaces of transfected Sf9 cells induced their homophilic aggregation, with the aggregation being abolished in the presence of recombinant immunoglobulin (Ig) domains of neuroglian. Neuroglian and its Ig domains also can interact with hemocyte-specific integrin (HS integrin) as demonstrated with an enzyme-linked immunoassay and a surface plasmon resonance (SPR) assay. Neuroglian double-stranded (ds) RNA not only depresses expression of neuroglian in hemocytes but also depresses the cell-mediated encapsulation response of these hemocytes to foreign surfaces. After injection of a monoclonal antibody (MAb 3B11) into M. sexta larvae that recognizes the Ig domains of neuroglian, the cell-mediated encapsulation response of hemocytes was likewise inhibited. The Ig domains of neuroglian are involved in both homophilic and heterophilic interactions, and subsets of these six different Ig domains may affect different functions of neuroglian.
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Affiliation(s)
- Shufei Zhuang
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
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20
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Eleftherianos I, Gökçen F, Felföldi G, Millichap PJ, Trenczek TE, ffrench-Constant RH, Reynolds SE. The immunoglobulin family protein Hemolin mediates cellular immune responses to bacteria in the insect Manduca sexta. Cell Microbiol 2006; 9:1137-47. [PMID: 17166232 DOI: 10.1111/j.1462-5822.2006.00855.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacterial recognition in the lepidopteran insect, Manduca sexta, is mediated by pattern recognition proteins including Hemolin, Peptidoglycan recognition protein (PGRP) and Immulectin-2. These proteins bind to molecular patterns present on the surface of bacteria and trigger a protective response involving humoral and cellular reactions. Cellular mechanisms mediated by haemocytes include phagocytosis, encapsulation, and the formation of melanotic nodules. Here, we show that a non-pathogenic strain of Escherichia coli induces mRNA transcription and protein expression of Hemolin and PGRP but not Immulectin-2 in Manduca haemocytes. This upregulation can be effectively prevented (knocked-down) using RNA interference (RNAi) following injection of double-stranded (ds) RNA. Knock-down of Hemolin significantly decreased the ability of insects to clear E. coli from the haemolymph and caused a reduction in the number of free haemocytes. RNAi of Hemolin reduced the ability of haemocytes to engulf bacteria through phagocytosis and to form melanotic nodules in vivo. Importantly, washed haemocytes taken from RNAi-treated insects showed reduced ability to form microaggregates around bacteria in vitro. This shows that the immune function affected by RNAi knock-down of Hemolin is intrinsic to the haemocytes. In contrast, RNAi of PGRP had no effect on any of these cellular immune functions. These results demonstrate the vital role of Hemolin in Manduca cellular immune responses.
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Nardi JB, Pilas B, Bee CM, Zhuang S, Garsha K, Kanost MR. Neuroglian-positive plasmatocytes of Manduca sexta and the initiation of hemocyte attachment to foreign surfaces. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2006; 30:447-62. [PMID: 16171863 DOI: 10.1016/j.dci.2005.06.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Revised: 05/03/2005] [Accepted: 06/10/2005] [Indexed: 05/04/2023]
Abstract
Observations of hemocyte aggregation on abiotic surfaces suggested that certain plasmatocytes from larvae of Manduca sexta act as foci for hemocyte aggregation. To establish how these particular plasmatocytes form initial attachments to foreign surfaces, they were cultured separately from other selected populations of hemocytes. While all circulating plasmatocytes immunolabel with anti-beta-integrin monoclonal antibody (MAb), only these larger plasmatocytes immunolabel with a MAb to the adhesion protein neuroglian. Neuroglian-negative plasmatocytes and granular cells that have been magnetically segregated from the majority of granular cells adhere to each other but fail to adhere to foreign substrata; by contrast, neuroglian-positive plasmatocytes that segregate with most granular cells adhere firmly to a substratum. Hemocytes form stable aggregates around the large, neuroglian-positive plasmatocytes. However, if neuroglian-positive plasmatocytes are separated from most granular cells, attachment of these plasmatocytes to foreign surfaces is suppressed.
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Affiliation(s)
- James B Nardi
- Department of Entomology, University of Illinois, 320 Morrill Hall, 505 South Goodwin Avenue, Urbana, IL 61801, USA.
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22
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Clark KD, Kim Y, Strand MR. Plasmatocyte sensitivity to plasmatocyte spreading peptide (PSP) fluctuates with the larval molting cycle. JOURNAL OF INSECT PHYSIOLOGY 2005; 51:587-96. [PMID: 15894005 DOI: 10.1016/j.jinsphys.2005.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Accepted: 03/03/2005] [Indexed: 05/02/2023]
Abstract
Plasmatocyte spreading peptide (PSP) is a cytokine from the moth Pseudoplusia includens that activates a class of hemocytes called plasmatocytes to bind and spread on foreign surfaces. Previous structure-function studies on PSP used plasmatocytes collected from P. includens larvae that were in the late stages of the last (fifth) instar. Here, we report that plasmatocyte sensitivity to PSP varied significantly during the fourth and fifth instar. PSP weakly activated plasmatocytes early in the instar when hemolymph juvenile hormone (JH) titers were relatively high and ecdysteroid titers were low, but strongly activated plasmatocytes late in the instar after JH titers declined and ecdysteroid titers rose. In contrast, plasmatocytes did not vary in their response to plasma, which contains other factors besides PSP that affect plasmatocyte function. In vitro assays indicated that 20-hydroxyecdysone (20E) dose-dependently synergized PSP activity, whereas the JH analog methoprene antagonized PSP activity. Methoprene had no effect on adhesion and spreading of granular cells, but plasmatocytes from larvae topically treated with methoprene exhibited a reduction in sensitivity to PSP. Collectively, these results indicate that plasmatocyte sensitivity to PSP fluctuates in relation to the molting cycle, and that PSP activity is affected by juvenoids and ecdysone.
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Affiliation(s)
- Kevin D Clark
- Department of Entomology, University of Georgia, Cedar Street, Athens, GA 30602, USA
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