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Holmes ML, Shine R, Waddle AW. Spontaneous reoccurrence of Batrachochytrium dendrobatidis infections in Australian green tree frogs (Litoria caerulea) following apparently successful heat therapy: Case report. Vet Res Commun 2024:10.1007/s11259-024-10449-2. [PMID: 38951465 DOI: 10.1007/s11259-024-10449-2] [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: 04/03/2024] [Accepted: 06/23/2024] [Indexed: 07/03/2024]
Abstract
Heat therapy has been reported as a safe, effective, and readily available treatment method for heat-tolerant frogs infected with Batrachochytrium dendrobatidis (Bd). We treated wild-caught Australian green tree frogs (Litoria caerulea) infected with Bd using two periods of elevated ambient room temperature (28.2-30.3 °C for 7 weeks followed by 28.9-34.1 °C for 4 weeks). Frogs exhibited persistent and even increasing infection loads in the first treatment period despite prolonged exposure to elevated temperatures, likely due to the presence of cooler microenvironments within their enclosure (25.5-27.0 °C). All frogs eventually returned negative qPCR tests for Bd at the end of the second treatment period, but detectable infections reoccurred one month after frogs were returned to standard housing temperatures (21.2-28.7 °C). Our findings suggest that elevated ambient temperature alone might not eliminate Bd in vivo but can reduce infections loads such that they are undetectable by qPCR analysis of skin swabs. Additional factors, such as cooler microenvironments within enclosures or relative humidity, may influence the success of heat therapy. We recommend further research into the combined effects of temperature and humidity during heat therapy and emphasize the importance of accurate temperature measurements as well as post-treatment monitoring at Bd-permissive temperatures to confirm successful clearance of infections.
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Affiliation(s)
- Madeleine L Holmes
- School of Natural Sciences, Macquarie University, Sydney, NSW, Australia.
| | - Richard Shine
- School of Natural Sciences, Macquarie University, Sydney, NSW, Australia
| | - Anthony W Waddle
- Applied Biosciences, Macquarie University, Sydney, NSW, Australia
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2
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Towe AE, Hardman RH, Cox S, Sheley WC, DeMarchi JA, Carter ED, Miller DL. PILOT STUDY OF INTRACOELOMIC TERBINAFINE IMPLANTS IN GREATER SIRENS ( SIREN LACERTINA). J Zoo Wildl Med 2024; 55:453-461. [PMID: 38875202 DOI: 10.1638/2023-0010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2024] [Indexed: 06/16/2024] Open
Abstract
Chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) has been documented in greater sirens (Siren lacertina) in the wild and in the pet trade. This study evaluated the use of terbinafine-impregnated implants for chytridiomycosis prophylaxis in greater sirens exposed to Bd. Implants were placed intracoelomically in both control (blank implant, n = 4) and treatment (24.5 mg of terbinafine implant, n = 4) groups. Sirens were exposed to Bd zoospores via 24-h immersion bath at 1 and 2 mon postimplant placement. Blood was collected monthly for plasma terbinafine levels, and skin swabs were collected weekly for Bd quantitative PCR. Animals with terbinafine implants had detectable concentrations of plasma terbinafine ranging from 17 to 102 ng/ml. Only one terbinafine-implanted animal had a peak concentration above the published minimum inhibitory concentration for terbinafine against Bd zoospores (63 ng/ml); however, it is unknown how plasma terbinafine concentrations relate to concentrations in the skin. There was no difference between the two treatment groups in clinical signs or Bd clearance rate, and no adverse effects from implants were observed. These findings indicate using intracoelomic drug implants for drug delivery in amphibians is safe; however, terbinafine efficacy in preventing Bd chytridiomycosis in sirens remains unclear. Further investigation of the use of intracoelomic implants and identification of effective drugs and doses in other amphibian species against Bd and other infectious diseases is warranted, as this may provide a practical method for long-term drug delivery in wildlife.
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Affiliation(s)
- Anastasia E Towe
- Department of Comparative and Experimental Medicine, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- University of Tennessee One Health Initiative, Knoxville, TN 37996, USA,
| | - Rebecca H Hardman
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
- University of Tennessee One Health Initiative, Knoxville, TN 37996, USA
| | - Sherry Cox
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
| | - Wesley C Sheley
- Department of Comparative and Experimental Medicine, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- University of Tennessee One Health Initiative, Knoxville, TN 37996, USA
| | - Joseph A DeMarchi
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
| | - E Davis Carter
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
- University of Tennessee One Health Initiative, Knoxville, TN 37996, USA
| | - Debra L Miller
- Department of Comparative and Experimental Medicine, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Institute of Agriculture, Knoxville, TN 37996, USA
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996, USA
- University of Tennessee One Health Initiative, Knoxville, TN 37996, USA
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3
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Berger L, Skerratt LF, Kosch TA, Brannelly LA, Webb RJ, Waddle AW. Advances in Managing Chytridiomycosis for Australian Frogs: Gradarius Firmus Victoria. Annu Rev Anim Biosci 2024; 12:113-133. [PMID: 38358840 DOI: 10.1146/annurev-animal-021122-100823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Extensive knowledge gains from research worldwide over the 25 years since the discovery of chytridiomycosis can be used for improved management. Strategies that have saved populations in the short term and/or enabled recovery include captive breeding, translocation into disease refugia, translocation from resistant populations, disease-free exclosures, and preservation of disease refuges with connectivity to previous habitat, while antifungal treatments have reduced mortality rates in the wild. Increasing host resistance is the goal of many strategies under development, including vaccination and targeted genetic interventions. Pathogen-directed strategies may be more challenging but would have broad applicability. While the search for the silver bullet solution continues, we should value targeted local interventions that stop extinction and buy time for evolution of resistance or development of novel solutions. As for most invasive species and infectious diseases, we need to accept that ongoing management is necessary. For species continuing to decline, proactive deployment and assessment of promising interventions are more valid than a hands-off, do-no-harm approach that will likely allow further extinctions.
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Affiliation(s)
- Lee Berger
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Lee F Skerratt
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Tiffany A Kosch
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Laura A Brannelly
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Rebecca J Webb
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Anthony W Waddle
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
- Applied Biosciences, Macquarie University, Sydney, New South Wales, Australia;
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4
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Ruiz VL, Robert J. The amphibian immune system. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220123. [PMID: 37305914 PMCID: PMC10258673 DOI: 10.1098/rstb.2022.0123] [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: 02/05/2023] [Accepted: 04/16/2023] [Indexed: 06/13/2023] Open
Abstract
Amphibians are at the forefront of bridging the evolutionary gap between mammals and more ancient, jawed vertebrates. Currently, several diseases have targeted amphibians and understanding their immune system has importance beyond their use as a research model. The immune system of the African clawed frog, Xenopus laevis, and that of mammals is well conserved. We know that several features of the adaptive and innate immune system are very similar for both, including the existence of B cells, T cells and innate-like T cells. In particular, the study of the immune system at early stages of development is benefitted by studying X. laevis tadpoles. The tadpoles mainly rely on innate immune mechanisms including pre-set or innate-like T cells until after metamorphosis. In this review we lay out what is known about the innate and adaptive immune system of X. laevis including the lymphoid organs as well as how other amphibian immune systems are similar or different. Furthermore, we will describe how the amphibian immune system responds to some viral, bacterial and fungal insults. This article is part of the theme issue 'Amphibian immunity: stress, disease and ecoimmunology'.
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Affiliation(s)
- Vania Lopez Ruiz
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
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5
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Assis VR, Robert J, Titon SCM. Introduction to the special issue Amphibian immunity: stress, disease and ecoimmunology. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220117. [PMID: 37305915 PMCID: PMC10258669 DOI: 10.1098/rstb.2022.0117] [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: 05/01/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Amphibian populations have been declining worldwide, with global climate changes and infectious diseases being among the primary causes of this scenario. Infectious diseases are among the primary drivers of amphibian declines, including ranavirosis and chytridiomycosis, which have gained more attention lately. While some amphibian populations are led to extinction, others are disease-resistant. Although the host's immune system plays a major role in disease resistance, little is known about the immune mechanisms underlying amphibian disease resistance and host-pathogen interactions. As ectotherms, amphibians are directly subjected to changes in temperature and rainfall, which modulate stress-related physiology, including immunity and pathogen physiology associated with diseases. In this sense, the contexts of stress, disease and ecoimmunology are essential for a better understanding of amphibian immunity. This issue brings details about the ontogeny of the amphibian immune system, including crucial aspects of innate and adaptive immunity and how ontogeny can influence amphibian disease resistance. In addition, the papers in the issue demonstrate an integrated view of the amphibian immune system associated with the influence of stress on immune-endocrine interactions. The collective body of research presented herein can provide valuable insights into the mechanisms underlying disease outcomes in natural populations, particularly in the context of changing environmental conditions. These findings may ultimately enhance our ability to forecast effective conservation strategies for amphibian populations. This article is part of the theme issue 'Amphibian immunity: stress, disease and ecoimmunology'.
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Affiliation(s)
- Vania Regina Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, 05508-900 São Paulo, Brazil
- College of Public Health, University of South Florida, Tampa, FL 33612-9415, USA
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA
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Paxton KL, Cassin-Sackett L, Atkinson CT, Videvall E, Campana MG, Fleischer RC. Gene expression reveals immune response strategies of naïve Hawaiian honeycreepers experimentally infected with introduced avian malaria. J Hered 2023; 114:326-340. [PMID: 36869776 DOI: 10.1093/jhered/esad017] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 03/01/2023] [Indexed: 03/05/2023] Open
Abstract
The unprecedented rise in the number of new and emerging infectious diseases in the last quarter century poses direct threats to human and wildlife health. The introduction to the Hawaiian archipelago of Plasmodium relictum and the mosquito vector that transmits the parasite has led to dramatic losses in endemic Hawaiian forest bird species. Understanding how mechanisms of disease immunity to avian malaria may evolve is critical as climate change facilitates increased disease transmission to high elevation habitats where malaria transmission has historically been low and the majority of the remaining extant Hawaiian forest bird species now reside. Here, we compare the transcriptomic profiles of highly susceptible Hawai'i 'amakihi (Chlorodrepanis virens) experimentally infected with P. relictum to those of uninfected control birds from a naïve high elevation population. We examined changes in gene expression profiles at different stages of infection to provide an in-depth characterization of the molecular pathways contributing to survival or mortality in these birds. We show that the timing and magnitude of the innate and adaptive immune response differed substantially between individuals that survived and those that succumbed to infection, and likely contributed to the observed variation in survival. These results lay the foundation for developing gene-based conservation strategies for Hawaiian honeycreepers by identifying candidate genes and cellular pathways involved in the pathogen response that correlate with a bird's ability to recover from malaria infection.
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Affiliation(s)
- Kristina L Paxton
- Center for Conservation Genomics, National Zoological Park and Conservation Biology Institute, Smithsonian Institution, Washington, DC 20008, USA
- Hawai'i Cooperative Studies Unit, University of Hawai'i Hilo, PO Box 44, Hawai'i National Park, HI 96718, USA
| | - Loren Cassin-Sackett
- Center for Conservation Genomics, National Zoological Park and Conservation Biology Institute, Smithsonian Institution, Washington, DC 20008, USA
- Department of Biology, University of Louisiana, Lafayette, LA 70503, USA
| | - Carter T Atkinson
- U.S. Geological Survey Pacific Island Ecosystems Research Center, PO Box 44, Hawai'i National Park, HI 96718, USA
| | - Elin Videvall
- Center for Conservation Genomics, National Zoological Park and Conservation Biology Institute, Smithsonian Institution, Washington, DC 20008, USA
- Department of Ecology, Evolution and Organismal Biology, Brown University, Providence, RI 02912, USA
| | - Michael G Campana
- Center for Conservation Genomics, National Zoological Park and Conservation Biology Institute, Smithsonian Institution, Washington, DC 20008, USA
| | - Robert C Fleischer
- Center for Conservation Genomics, National Zoological Park and Conservation Biology Institute, Smithsonian Institution, Washington, DC 20008, USA
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Woodhams DC, McCartney J, Walke JB, Whetstone R. The adaptive microbiome hypothesis and immune interactions in amphibian mucus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 145:104690. [PMID: 37001710 DOI: 10.1016/j.dci.2023.104690] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 05/20/2023]
Abstract
The microbiome is known to provide benefits to hosts, including extension of immune function. Amphibians are a powerful immunological model for examining mucosal defenses because of an accessible epithelial mucosome throughout their developmental trajectory, their responsiveness to experimental treatments, and direct interactions with emerging infectious pathogens. We review amphibian skin mucus components and describe the adaptive microbiome as a novel process of disease resilience where competitive microbial interactions couple with host immune responses to select for functions beneficial to the host. We demonstrate microbiome diversity, specificity of function, and mechanisms for memory characteristic of an adaptive immune response. At a time when industrialization has been linked to losses in microbiota important for host health, applications of microbial therapies such as probiotics may contribute to immunotherapeutics and to conservation efforts for species currently threatened by emerging diseases.
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Affiliation(s)
- Douglas C Woodhams
- Department of Biology, University of Massachusetts Boston, Boston, MA, 02125, USA.
| | - Julia McCartney
- Department of Biology, University of Massachusetts Boston, Boston, MA, 02125, USA
| | - Jenifer B Walke
- Department of Biology, Eastern Washington University, Cheney, WA, 99004-2440, USA
| | - Ross Whetstone
- Department of Biology, University of Massachusetts Boston, Boston, MA, 02125, USA
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8
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Kaganer AW, Ossiboff RJ, Keith NI, Schuler KL, Comizzoli P, Hare MP, Fleischer RC, Gratwicke B, Bunting EM. Immune priming prior to pathogen exposure sheds light on the relationship between host, microbiome and pathogen in disease. ROYAL SOCIETY OPEN SCIENCE 2023; 10:220810. [PMID: 36756057 PMCID: PMC9890126 DOI: 10.1098/rsos.220810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Dynamic interactions between host, pathogen and host-associated microbiome dictate infection outcomes. Pathogens including Batrachochytrium dendrobatidis (Bd) threaten global biodiversity, but conservation efforts are hindered by limited understanding of amphibian host, Bd and microbiome interactions. We conducted a vaccination and infection experiment using Eastern hellbender salamanders (Cryptobranchus alleganiensis alleganiensis) challenged with Bd to observe infection, skin microbial communities and gene expression of host skin, pathogen and microbiome throughout the experiment. Most animals survived high Bd loads regardless of their vaccination status and vaccination did not affect pathogen load, but host gene expression differed based on vaccination. Oral vaccination (exposure to killed Bd) stimulated immune gene upregulation while topically and sham-vaccinated animals did not significantly upregulate immune genes. In early infection, topically vaccinated animals upregulated immune genes but orally and sham-vaccinated animals downregulated immune genes. Bd increased pathogenicity-associated gene expression in late infection when Bd loads were highest. The microbiome was altered by Bd, but there was no correlation between anti-Bd microbe abundance or richness and pathogen burden. Our observations suggest that hellbenders initially generate a vigorous immune response to Bd, which is ineffective at controlling disease and is subsequently modulated. Interactions with antifungal skin microbiota did not influence disease progression.
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Affiliation(s)
- Alyssa W. Kaganer
- Department of Natural Resources and the Environment, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14853, USA
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
| | - Robert J. Ossiboff
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Nicole I. Keith
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Biology Department, Hamilton College, Clinton, NY, 13323, USA
| | - Krysten L. Schuler
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Comizzoli
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
| | - Matthew P. Hare
- Department of Natural Resources and the Environment, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Robert C. Fleischer
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
| | - Brian Gratwicke
- Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Elizabeth M. Bunting
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
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Gomes FR, Madelaire CB, Moretti EH, Titon SCM, Assis VR. Immunoendocrinology and Ecoimmunology in Brazilian Anurans. Integr Comp Biol 2022; 62:1654-1670. [PMID: 35411921 DOI: 10.1093/icb/icac014] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
This paper reviews several aspects of immunoendocrinology and ecoimmunology in Brazilian species of anurans under investigation for more than a decade, including (1) patterns of annual covariation of circulating steroids, calling behavior and innate immunity, (2) endocrine and immune correlates of calling performance, (3) behavioral and physiological correlates of parasite load, (4) thermal sensitivity of immune function, and (5) endocrine and immunomodulation by experimental exposure to acute and chronic stressors, as well as to endocrine manipulations and simulated infections. Integrated results have shown an immunoprotective role of increased steroid plasma levels during reproductive activity in calling males. Moreover, a higher helminth parasite load is associated with changes in several behavioral and physiological traits under field conditions. We also found anuran innate immunity is generally characterized by eurythermy, with maximal performance observed in temperatures close to normal and fever thermal preferendum. Moreover, the aerobic scope of innate immune response is decreased at fever thermal preferendum. Experimental exposure to stressors results in increased corticosterone plasma levels and immune redistribution, with an impact on immune function depending on the duration of the stress exposure. Interestingly, the fate of immunomodulation by chronic stressors also depends in part on individual body condition. Acute treatment with corticosterone generally enhances immune function, while prolonged exposure results in immunosuppression. Still, the results of hormonal treatment are complex and depend on the dose, duration of treatment, and the immune variable considered. Finally, simulated infection results in complex modulation of the expression of cytokines, increased immune function, activation of the Hypothalamus-Pituitary-Interrenal axis, and decreased activity of the Hypothalamus-Pituitary-Gonadal axis, as well as reduced melatonin plasma levels, suggesting that anurans have a functional Immune-Pineal axis, homologous to that previously described for mammals. These integrated and complementary approaches have contributed to a better understanding of physiological mechanisms and processes, as well as ecological and evolutionary implications of anuran immunoendocrinology.
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Affiliation(s)
- Fernando Ribeiro Gomes
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, São Paulo, SP 05508-090, Brasil
| | - Carla Bonetti Madelaire
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, São Paulo, SP 05508-090, Brasil.,School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154, USA
| | - Eduardo Hermógenes Moretti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes, 1730, São Paulo, SP 05508-900, Brasil
| | - Stefanny Christie Monteiro Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, São Paulo, SP 05508-090, Brasil
| | - Vania Regina Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, São Paulo, SP 05508-090, Brasil
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10
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Humphries JE, Lanctôt CM, Robert J, McCallum HI, Newell DA, Grogan LF. Do immune system changes at metamorphosis predict vulnerability to chytridiomycosis? An update. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 136:104510. [PMID: 35985564 DOI: 10.1016/j.dci.2022.104510] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/20/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Amphibians are among the vertebrate groups suffering great losses of biodiversity due to a variety of causes including diseases, such as chytridiomycosis (caused by the fungal pathogens Batrachochytrium dendrobatidis and B. salamandrivorans). The amphibian metamorphic period has been identified as being particularly vulnerable to chytridiomycosis, with dramatic physiological and immunological reorganisation likely contributing to this vulnerability. Here, we overview the processes behind these changes at metamorphosis and then perform a systematic literature review to capture the breadth of empirical research performed over the last two decades on the metamorphic immune response. We found that few studies focused specifically on the immune response during the peri-metamorphic stages of amphibian development and fewer still on the implications of their findings with respect to chytridiomycosis. We recommend future studies consider components of the immune system that are currently under-represented in the literature on amphibian metamorphosis, particularly pathogen recognition pathways. Although logistically challenging, we suggest varying the timing of exposure to Bd across metamorphosis to examine the relative importance of pathogen evasion, suppression or dysregulation of the immune system. We also suggest elucidating the underlying mechanisms of the increased susceptibility to chytridiomycosis at metamorphosis and the associated implications for population persistence. For species that overlap a distribution where Bd/Bsal are now endemic, we recommend a greater focus on management strategies that consider the important peri-metamorphic period.
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Affiliation(s)
- Josephine E Humphries
- School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Centre for Planetary Health and Food Security, Griffith University, Southport, Queensland, 4222, Australia; Faculty of Science and Engineering, Southern Cross University, Lismore, New South Wales, 2480, Australia.
| | - Chantal M Lanctôt
- School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Australian Rivers Institute, Griffith University, Southport, Queensland, 4222, Australia
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, 14642, Rochester, NY, United States
| | - Hamish I McCallum
- School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Centre for Planetary Health and Food Security, Griffith University, Southport, Queensland, 4222, Australia
| | - David A Newell
- Faculty of Science and Engineering, Southern Cross University, Lismore, New South Wales, 2480, Australia
| | - Laura F Grogan
- School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Centre for Planetary Health and Food Security, Griffith University, Southport, Queensland, 4222, Australia
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11
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Neely WJ, Greenspan SE, Stahl LM, Heraghty SD, Marshall VM, Atkinson CL, Becker CG. Habitat Disturbance Linked with Host Microbiome Dispersion and Bd Dynamics in Temperate Amphibians. MICROBIAL ECOLOGY 2022; 84:901-910. [PMID: 34671826 DOI: 10.1007/s00248-021-01897-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
Anthropogenic habitat disturbances can dramatically alter ecological community interactions, including host-pathogen dynamics. Recent work has highlighted the potential for habitat disturbances to alter host-associated microbial communities, but the associations between anthropogenic disturbance, host microbiomes, and pathogens are unresolved. Amphibian skin microbial communities are particularly responsive to factors like temperature, physiochemistry, pathogen infection, and environmental microbial reservoirs. Through a field survey on wild populations of Acris crepitans (Hylidae) and Lithobates catesbeianus (Ranidae), we assessed the effects of habitat disturbance and connectivity on environmental bacterial reservoirs, Batrachochytrium dendrobatidis (Bd) infection, and skin microbiome composition. We found higher measures of microbiome dispersion (a measure of community variability) in A. crepitans from more disturbed ponds, supporting the hypothesis that disturbance increases stochasticity in biological communities. We also found that habitat disturbance limited microbiome similarity between locations for both species, suggesting greater isolation of bacterial assemblages in more disturbed areas. Higher disturbance was associated with lower Bd prevalence for A. crepitans, which could signify suboptimal microclimates for Bd in disturbed habitats. Combined, our findings show that reduced microbiome stability stemming from habitat disturbance could compromise population health, even in the absence of pathogenic infection.
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Affiliation(s)
- Wesley J Neely
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA.
| | - Sasha E Greenspan
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
| | - Leigha M Stahl
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
| | - Sam D Heraghty
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
| | - Vanessa M Marshall
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
| | - Carla L Atkinson
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
| | - C Guilherme Becker
- Department of Biology, The University of Alabama, 1301 Sciences and Engineering Complex, 300 Hackberry Ln, Tuscaloosa, AL, 35487, USA
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12
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Assis VR, Titon SCM, Voyles J. Ecoimmunology: What Unconventional Organisms Tell Us after Two Decades. Integr Comp Biol 2022; 62:icac148. [PMID: 36250609 DOI: 10.1093/icb/icac148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 09/13/2022] [Accepted: 09/18/2022] [Indexed: 02/18/2024] Open
Affiliation(s)
- Vania R Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo SP 05508-090, Brasil
| | - Stefanny C M Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo SP 05508-090, Brasil
| | - Jamie Voyles
- Department of Biology, University of Nevada, Reno, Reno, NV 89557, USA
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13
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Torres-Sánchez M, Villate J, McGrath-Blaser S, Longo AV. Panzootic chytrid fungus exploits diverse amphibian host environments through plastic infection strategies. Mol Ecol 2022; 31:4558-4570. [PMID: 35796691 DOI: 10.1111/mec.16601] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 11/29/2022]
Abstract
While some pathogens are limited to single species, others can colonize many hosts, likely contributing to the emergence of novel disease outbreaks. Despite this biodiversity threat, traits associated with host niche expansions are not well understood in multi-host pathogens. Here, we aimed to uncover functional machinery driving multi-host invasion by focusing on Batrachochytrium dendrobatidis (Bd), a pathogen that infects the skin of hundreds of amphibians worldwide. We performed a meta-analysis of Bd gene expression using data from published infection experiments and newly generated profiles. We analyzed Bd transcriptomic landscapes across the skin of 14 host species, reconstructed Bd isolates phylogenetic relationships, and inferred the origin and evolutionary history of differentially expressed genes under a phylogenetic framework comprising other 12 zoosporic fungi. Bd displayed plastic infection strategies when challenged by hosts with different disease susceptibility. Our analyses identified sets of differentially expressed genes under host environments with similar infection outcome. We stressed nutritional immunity and gene silencing as important processes required to overcome challenging skin environments in less susceptible hosts. Overall, Bd genes expressed during amphibian skin exploitation have arisen mainly via gene duplications with great family expansions, increasing the gene copy events previously described for this fungal species. Finally, we provide a comprehensive gene dataset that can be used to further examine eco-evolutionary hypotheses for this host-pathogen system. Our study supports the idea that host environments exert contrasting selective pressures, such that gene expression plasticity could be one of the evolutionary keys leading to the success of multi-host pathogens.
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Affiliation(s)
| | - Jennifer Villate
- Department of Biology, University of Florida, 32611, Gainesville, FL
| | | | - Ana V Longo
- Department of Biology, University of Florida, 32611, Gainesville, FL
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14
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Kásler A, Ujszegi J, Holly D, Jaloveczki B, Gál Z, Hettyey A. In vitro thermal tolerance of a hypervirulent lineage of Batrachochytrium dendrobatidis: Growth arrestment by elevated temperature and recovery following thermal treatment. Mycologia 2022; 114:661-669. [PMID: 35666647 DOI: 10.1080/00275514.2022.2065443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Chytridiomycosis, an emerging infectious disease caused by Batrachochytrium dendrobatidis (Bd), poses a serious threat to amphibians. The thermal optimum of Bd is lower than that of most amphibians, providing an opportunity to cure infected individuals with elevated temperature. However, this approach presupposes detailed knowledge about the thermal tolerance of the fungus. To determine the temperature that may effectively reduce infection burdens in vivo, detailed in vitro studies are needed to characterize thermal tolerance of the fungus without complexities introduced by the species-specific characteristics of hosts' immune systems. The aim of our study was to evaluate the thermal tolerance of a hypervirulent isolate of Bd, considering the limits of its thermal tolerance and its capacity to rebound following heat treatment. We incubated Bd cell cultures at five different temperatures (21, 25.5, 27, 29, or 30.5 C) for one of six exposure durations (3, 4, 5, 6, 7, or 8 days) and subsequently counted the number of zoospores to assess the temperature dependence of Bd growth. We observed intensive Bd growth at 21 C. At 25.5 C, the number of zoospores also increased over time, but the curve plateaued at about half of the maximum values observed in the lower temperature treatment. At temperatures of 27 C and above, the fungus showed no measurable growth. However, when we moved the cultures back to 21 C after the elevated temperature treatments, we observed recovery of Bd growth in all cultures previously treated at 27 C. At 29 C, a treatment duration of 8 days was necessary to prevent recovery of Bd growth, and at 30.5 C a treatment duration of 5 days was needed to achieve the same result, revealing that these moderately elevated temperatures applied for only a few days have merely a fungistatic rather than a fungicidal effect under in vitro conditions.
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Affiliation(s)
- Andrea Kásler
- Lendület Evolutionary Ecology Research Group, Centre for Agricultural Research, Plant Protection Institute, Eötvös Loránd Research Network, Nagykovácsi str. 26-30., Budapest 1029, Hungary.,Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest 1117, Hungary
| | - János Ujszegi
- Lendület Evolutionary Ecology Research Group, Centre for Agricultural Research, Plant Protection Institute, Eötvös Loránd Research Network, Nagykovácsi str. 26-30., Budapest 1029, Hungary.,Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest 1117, Hungary
| | - Dóra Holly
- Lendület Evolutionary Ecology Research Group, Centre for Agricultural Research, Plant Protection Institute, Eötvös Loránd Research Network, Nagykovácsi str. 26-30., Budapest 1029, Hungary.,Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest 1117, Hungary
| | - Boglárka Jaloveczki
- Department of Zoology, Centre for Agricultural Research, Plant Protection Institute, Budapest 1029, Hungary
| | - Zoltán Gál
- Institute of Genetics and Biotechnology, Animal Biotechnology Department, Hungarian University of Agriculture and Life Sciences, Gödöllő 2100, Hungary
| | - Attila Hettyey
- Lendület Evolutionary Ecology Research Group, Centre for Agricultural Research, Plant Protection Institute, Eötvös Loránd Research Network, Nagykovácsi str. 26-30., Budapest 1029, Hungary.,Department of Ecology, University of Veterinary Medicine, Budapest 1078, Hungary
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15
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Gass J, Voyles J. When Defenses Fail: Atelopus zeteki Skin Secretions Increase Growth of the Pathogen Batrachochytrium dendrobatidis. Integr Comp Biol 2022; 62:1595-1605. [PMID: 35640912 PMCID: PMC9801971 DOI: 10.1093/icb/icac060] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/30/2022] [Accepted: 05/24/2022] [Indexed: 01/05/2023] Open
Abstract
To combat the threat of emerging infectious diseases in wildlife, ecoimmunologists seek to understand the complex interactions among pathogens, their hosts, and their shared environments. The cutaneous fungal pathogen Batrachochytrium dendrobatidis (Bd), has led to the decline of innumerable amphibian species, including the Panamanian golden frog (Atelopus zeteki). Given that Bd can evade or dampen the acquired immune responses of some amphibians, nonspecific immune defenses are thought to be especially important for amphibian defenses against Bd. In particular, skin secretions constitute a vital component of amphibian innate immunity against skin infections, but their role in protecting A. zeteki from Bd is unknown. We investigated the importance of this innate immune component by reducing the skin secretions from A. zeteki and evaluating their effectiveness against Bd in vitro and in vivo. Following exposure to Bd in a controlled inoculation experiment, we compared key disease characteristics (e.g., changes in body condition, prevalence, pathogen loads, and survival) among groups of frogs that had their skin secretions reduced and control frogs that maintained their skin secretions. Surprisingly, we found that the skin secretions collected from A. zeteki increased Bd growth in vitro. This finding was further supported by infection and survival patterns in the in vivo experiment where frogs with reduced skin secretions tended to have lower pathogen loads and survive longer compared to frogs that maintained their secretions. These results suggest that the skin secretions of A. zeteki are not only ineffective at inhibiting Bd but may enhance Bd growth, possibly leading to greater severity of disease and higher mortality in this highly vulnerable species. These results differ from those of previous studies in other amphibian host species that suggest that skin secretions are a key defense in protecting amphibians from developing severe chytridiomycosis. Therefore, we suggest that the importance of immune components cannot be generalized across all amphibian species or over time. Moreover, the finding that skin secretions may be enhancing Bd growth emphasizes the importance of investigating these immune components in detail, especially for species that are a conservation priority.
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Affiliation(s)
- Jordan Gass
- Department of Biology, University of Nevada at Reno, 1664 North Virginia Street, Reno, NV 89557, USA
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16
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Kásler A, Ujszegi J, Holly D, Üveges B, Móricz ÁM, Herczeg D, Hettyey A. Metamorphic common toads keep chytrid infection under control, but at a cost. J Zool (1987) 2022. [DOI: 10.1111/jzo.12974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. Kásler
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
- Doctoral School of Biology Institute of Biology ELTE Eötvös Loránd University Budapest Hungary
| | - J. Ujszegi
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
- Department of Systematic Zoology and Ecology Institute of Biology ELTE Eötvös Loránd University Budapest Hungary
| | - D. Holly
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
- Doctoral School of Biology Institute of Biology ELTE Eötvös Loránd University Budapest Hungary
| | - B. Üveges
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
- Molecular Ecology and Evolution at Bangor School of Natural Sciences Bangor University Bangor UK
| | - Á. M. Móricz
- Department of Pathophysiology Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
| | - D. Herczeg
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
| | - A. Hettyey
- Lendület Evolutionary Ecology Research Group Centre for Agricultural Research Plant Protection Institute Eötvös Loránd Research Network Budapest Hungary
- Department of Systematic Zoology and Ecology Institute of Biology ELTE Eötvös Loránd University Budapest Hungary
- Department of Ecology University of Veterinary Medicine Budapest Hungary
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17
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Jiang N, Fan Y, Zhou Y, Meng Y, Liu W, Li Y, Xue M, Robert J, Zeng L. The Immune System and the Antiviral Responses in Chinese Giant Salamander, Andrias davidianus. Front Immunol 2021; 12:718627. [PMID: 34675918 PMCID: PMC8524050 DOI: 10.3389/fimmu.2021.718627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/16/2021] [Indexed: 12/25/2022] Open
Abstract
The Chinese giant salamander, belonging to an ancient amphibian lineage, is the largest amphibian existing in the world, and is also an important animal for artificial cultivation in China. However, some aspects of the innate and adaptive immune system of the Chinese giant salamander are still unknown. The Chinese giant salamander iridovirus (GSIV), a member of the Ranavirus genus (family Iridoviridae), is a prominent pathogen causing high mortality and severe economic losses in Chinese giant salamander aquaculture. As a serious threat to amphibians worldwide, the etiology of ranaviruses has been mainly studied in model organisms, such as the Ambystoma tigrinum and Xenopus. Nevertheless, the immunity to ranavirus in Chinese giant salamander is distinct from other amphibians and less known. We review the unique immune system and antiviral responses of the Chinese giant salamander, in order to establish effective management of virus disease in Chinese giant salamander artificial cultivation.
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Affiliation(s)
- Nan Jiang
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- Department of Microbiology and Immunology, University of Rochester Medical Center, New York, NY, United States
| | - Yuding Fan
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yong Zhou
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yan Meng
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Wenzhi Liu
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yiqun Li
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Mingyang Xue
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, New York, NY, United States
| | - Lingbing Zeng
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
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18
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Eskew EA, Fraser D, Vonhof MJ, Pinsky ML, Maslo B. Host gene expression in wildlife disease: making sense of species-level responses. Mol Ecol 2021; 30:6517-6530. [PMID: 34516689 DOI: 10.1111/mec.16172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 08/16/2021] [Accepted: 08/31/2021] [Indexed: 12/11/2022]
Abstract
Emerging infectious diseases are significant threats to wildlife conservation, yet the impacts of pathogen exposure and infection can vary widely among host species. As such, conservation biologists and disease ecologists have increasingly aimed to understand species-specific host susceptibility using molecular methods. In particular, comparative gene expression assays have been used to contrast the transcriptomic responses of disease-resistant and disease-susceptible hosts to pathogen exposure. This work usually assumes that the gene expression responses of disease-resistant species will reveal the activation of molecular pathways contributing to host defence. However, results often show that disease-resistant hosts undergo little gene expression change following pathogen challenge. Here, we discuss the mechanistic implications of these "null" findings and offer methodological suggestions for future molecular studies of wildlife disease. First, we highlight that muted transcriptomic responses with minimal immune system recruitment may indeed be protective for nonsusceptible hosts if they limit immunopathology and promote pathogen tolerance in systems where susceptible hosts suffer from genetic dysregulation. Second, we argue that overly narrow investigation of responses to pathogen exposure may overlook important, constitutively active molecular pathways that underlie species-specific defences. Finally, we outline alternative study designs and approaches that complement interspecific transcriptomic comparisons, including intraspecific gene expression studies and genomic methods to detect signatures of selection. Collectively, these insights will help ecologists extract maximal information from conservation-relevant transcriptomic data sets, leading to a deeper understanding of host defences and, ultimately, the implementation of successful conservation interventions.
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Affiliation(s)
- Evan A Eskew
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA.,Department of Biology, Pacific Lutheran University, Tacoma, Washington, USA
| | - Devaughn Fraser
- Wildlife Genetics Research Laboratory, California Department of Fish and Wildlife, Sacramento, California, USA
| | - Maarten J Vonhof
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan, USA
| | - Malin L Pinsky
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Brooke Maslo
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
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