MinireviewThe scope of the crustacean immune system for disease control
Graphical abstract
Highlights
► Recent advances in our understanding of decapod immunity are summarised. ► Five avenues offer promise for mitigating disease, including studies of gut immunity. ► The potential of diverse pattern recognition and antimicrobial peptides are considered. ► Challenges to progress are identified, including the lack of cell lines and genomic data.
Introduction
For future generations, and in response to the increasing global population, the reliance on crustacean shellfish as a source of animal protein is set to increase. Inevitably this will lead to an increase in demand from wild fishery stocks and expansion of aquaculture (Subasinghe et al., 2009, Stentiford et al., 2012). However, the expansion of fishery effort in wild species and the increase in aquaculture across new species and new countries are not without significant issue, including the potential for habitat destruction, socioeconomic challenges, an increased prevalence or geographic spread of existing diseases and the potential for new diseases to arise.
Pathogens of commercial significance to the global crustacean shellfish industry (fisheries and aquaculture) have been reviewed in detail by other contributions to this volume. As described, significant economic global impacts are caused by viruses (e.g. White Spot Syndrome Virus (WSSV) and Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV)), Gram-negative bacteria (e.g. Vibrio harveyi, Vibrio penaecidia, and opportunistic vibrios) and protozoa (e.g. Hematodinium spp.). Regionally, other pathogens are also commercially significant, including the Gram-positive bacterium, Aerococcus viridans var homari, which detrimentally affects wild-caught lobsters Homarus americanus in Canada and the United States.
The intention of this review is to provide a brief but broad overview of our current understanding of the crustacean innate immune system, with special reference to the Decapoda, and to identify avenues for future focus as part of a suite of solutions to ensure global food security using farmed and wild caught crustacean shellfish.
Section snippets
Current knowledge of the crustacean immune mechanism – an overview
The immune system of decapods is comprised of both cellular and non-cellular (humoral) components. Whilst this classification is operationally useful it is an artificial distinction. There is considerable integration of the cellular and humoral compartments to produce a single coordinated system. Cellular responses are triggered or enhanced by factors present within the plasma and humoral elements are often produced in, and secreted from, circulating and fixed haemocytes. Components and
Existing prophylactic treatments of crustacean disease based on current knowledge
In the preceding discussion a brief overview of current knowledge of the immune response in commercially important crustaceans has been provided. Whilst the details of many pathways, and how they inter-relate, are still unknown these limited data have provided a basis from which attempts have been made to combat disease within crustacean aquaculture by prophylaxis. The intention here has been to augment the innate immune response prior to actual pathogen exposure. Efforts have focussed on
Directions for future research
Current approaches to the prophylactic treatment of disease within crustacean aquaculture should be superseded by new strategies that are based on a more complete understanding of the complexity of the immune response within the Decapoda. The goal should be to manipulate the immune system in a calculated way so as to avoid triggering localised and/or systemic haemocyte degranulation or the inappropriate activation of cascades leading to the release of toxic but non-specific immune effectors.
Practical challenges to future study
From the above discussion it is fair to conclude that very significant advances have been made recently in our understanding of crustacean immunology. However, impediments to progress do exist. From a research standpoint the lack of an immortal crustacean cell line represents a significant impediment to progress. Research in crustacean immunity, and in particular host/virus interactions, has always trailed that of advances in our understanding of insect immunology. In part this is attributable
Summary
This is undoubtedly an exciting time in the field of invertebrate immunology. New discoveries of PRPs, immune effectors and regulatory pathways are offering fundamental new insights in our efforts to understand disease in cultured populations and also to develop knowledge of environmental effects on host/pathogen interactions within a fishery context. The pace at which new discoveries are reported has increased in the past ten years and the number of research groups around the world with
Acknowledgment
The author would like to acknowledge the generous financial support of the OECD in presenting this manuscript.
References (132)
- et al.
Hemocyte components in crustaceans convert hemocyanin into a phenoloxidase-like enzyme
Comparative Biochemistry and Physiology Part B
(2003) - et al.
Antimicrobial peptide gene expression in tiger shrimp, Penaeus monodon in response to gram-positive bacterial probionts and white spot virus challenge
Aquaculture
(2011) - et al.
Molecular characterization of a crustin-like antimicrobial peptide in the giant tiger shrimp, Penaeus monodon, and its expression profile in response to various immunostimulants and challenge with WSSV
Immunobiology
(2011) - et al.
Molecular cloning and expression of a Toll receptor in the giant tiger shrimp, Penaeus monodon
Fish and Shellfish Immunology
(2007) - et al.
Identification of defence effectors in the haemolymph of crustaceans with particular reference to the shrimp Penaeus japonicus (Bate), prospects and applications
Fish and Shellfish Immunology
(1995) - et al.
Isolation and characterisation of two antimicrobial peptides from haemocytes of the American lobster Homarus americanus
Fish and Shellfish Immunology
(2008) - et al.
Gene characterisation, isoforms and recombinant expression of Carcinin, an antibacterial protein from the shore crab, Carcinus maenas
Molecular Immunology
(2007) - et al.
Markedly reduced severity of Dengue virus infection in mosquito cell cultures persistently infected with Aedes albopictus densovirus (AalDNV)
Virology
(2004) - et al.
Generation of superoxide anion and SOD activity in haemocytes and muscle of American white shrimp (Litopenaeus vannamei) as a response to β-glucan and sulphated polysaccharide
Fish Shellfish Immunology
(2002) - et al.
The putative invertebrate adaptive immune protein Litopenaeus vannamei Dscam (LvDscam) is the first reported Dscam to lack a transmembrane domain and cytoplasmic tail
Developmental and Comparative Immunology
(2009)
Penaeus monodon Dscam (PmDscam) has a highly diverse cytoplasmic tail and is the first membrane-bound shrimp Dscam to be reported
Fish and Shellfish Immunology
Melanization immune responses in mosquito vectors
TRENDS in Parasitology
Defective interfering particles of poliovirus. 3. interference and enrichment
Journal of Molecular Biology
Diversity in penaeidin antimicrobial peptide form and function
Developmental and Comparative Immunology
Anti-lipopolysaccharide factor in Litopenaeus vannamei (LvALF): a broad spectrum antimicrobial peptide essential for shrimp immunity against bacterial and fungal infection
Molecular Immunology
A relationship between antimicrobial peptide gene expression and capacity of a selected shrimp line to survive a Vibrio infection
Molecular Immunology
Presence of multiple viruses in non-diseased cultivated shrimp at harvest
Aquaculture
A review on the interactions between gut microflora and digestive mucosal immunity. Possible ways to improve the health of rabbits
Livestock Science
Within-host spatial dynamics of viruses and defective interfering particles
Journal of Theoretical Biology
Nutrition and gut immunity
The Surgical Clinics of North America
Differential gene expression in White Spot Syndrome Virus (WSSV)-infected naive and previously challenged Pacific white shrimp Penaeus (Litopenaeus) vannamei
Aquaculture
Lipopolysaccharide induces DNA-synthesis in a sub-population of hemocytes from the swimming crab, Liocarcinus depurator
Developmental and Comparative Immunology
RNAi knock-down of the Litopenaeus vannamei Toll gene (LvToll) significantly increases mortality and reduces bacterial clearance after challenge with Vibrio harveyi
Developmental and Comparative Immunology
In vivo effects of immunostimulants on gene expression and disease resistance in lobster (Homarus gammarus) post-larval stage VI (PLVI) juveniles
Molecular Immunology
Enhancement of disease resistance of kuruma shrimp, Penaeus japonicus, after oral administration of peptidoglycan derived from Biifidobacterium thermophilium
Aquaculture
Studies on nitric oxide synthase activity in haemocytes of shrimps Fenneropenaeus chinensis and Marsupenaeus japonicus after white spot syndrome virus infection
Nitric oxide
Cell-mediated immunity in arthropods: hematopoiesis, coagulation, melanization and opsonisation
Immunobiology
Crustacean haemocytes and haematopoiesis
Aquaculture
Peroxinectin, a novel cell adhesion protein from crayfish blood
Biochemical and Biophysical Research Communications
Characterization and expression of a new subfamily member of penaeidin antimicrobial peptides (penaeidin 5) from Fenneropenaeus chinensis
Molecular Immunology
Mosquito cells accommodate balanced, persistent co-infections with a densovirus and Dengue virus
Developmental and Comparative Immunology
Processing of an antibacterial peptide from hemocyanin of the freshwater crayfish Pacifastacus leniusculus
The Journal of Biological Chemistry
A lipopolysaccharide- and beta-1,3-glucan-binding protein from hemocytes of the freshwater crayfish Pacifastacus leniusculus – Purification, characterization, and cDNA cloning
Journal of Biological Chemistry
A Dorsal homolog (FcDorsal) in the Chinese shrimp Fenneropenaeus chinensis is responsive to both bacteria and WSSV challenge
Developmental and Comparative Immunology
Tiger shrimp (Penaeus monodon) penaeidin possesses cytokine features to promote integrin-mediated granulocyte and semi-granulocyte adhesion
Fish and Shellfish Immunology
Crustacean hematopoeisis and the astakine cytokines
Blood
Antiviral immunity in crustaceans
Fish and Shellfish Immunology
Peptidoglycan activation of the proPO-system without a peptidoglycan receptor protein (PGRP)?
Developmental and Comparative Immunology
Trypanocidal and leishmanicidal activities of different antimicrobial peptides (AMPS) isolated from aquatic animals
Experimental Parasitology
Effects of LPS on circulating haemocytes in crustaceans in vivo
Fish and Shellfish Immunology
Purification, characterization and cDNA cloning of a novel lipopolysaccharide-binding lectin from the shrimp Penaeus monodon
Developmental and Comparative Immunology
PmAV, a novel gene involved in virus resistance of shrimp Penaeus monodon
FEBS Letters
Molecular cloning of a C-type lectin (LvLT) from the shrimp Litopenaeus vannamei: Early gene down-regulation after WSSV infection
Fish and Shellfish Immunology
Identification of cDNA encoding Toll receptor, MjToll gene from kuruma shrimp, Marsupenaeus japonicus
Fish and Shellfish Immunology
Identification of genes expressed in response to yellow head virus infection in the black tiger shrimp, Penaeus monodon, by suppression subtractive hybridization
Developmental and Comparative Immunology
An inducible nitric oxide synthase (NOS) is expressed in haemocytes of the spiny lobster Panulirus argus: cloning, characterization and expression analysis
Fish and Shellfish Immunology
Isolation and in vitro characterisation of prohaemocytes from the spider crab, Hyas araneus (L.)
Developmental and Comparative Immunology
Drosophila Dscam is an axon guidance receptor exhibiting extraordinary molecular diversity
Cell
Evidence for circulating hemocyte proliferation in the shrimp, Penaeus japonicus
Developmental and Comparative Immunology
Identification and molecular characterization of a Spätzle-like protein from Chinese shrimp (Fenneropenaeus chinensis)
Fish and Shellfish Immunology
Cited by (109)
Effects of dietary melatonin on antioxidant and immune function of the Pacific white shrimp (Litopenaeus vannamei), as determined by transcriptomic analysis
2023, Comparative Biochemistry and Physiology - Part D: Genomics and ProteomicsInsights into molecular aspects of pathogenesis and disease management in acute hepatopancreatic necrosis disease (AHPND): An updated review
2023, Fish and Shellfish ImmunologyMolecular characterization and expression analysis of a QM protein gene in Chinese mitten crab Eriocheir sinensis
2023, Fish and Shellfish Immunology