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Horgan M, Martinez ME, Archer LL, Duignan PJ, Wellehan JFX. DEVELOPMENT AND VALIDATION OF A NOVEL DUPLEX PROBE-HYBRIDIZATION QUANTITATIVE PCR FOR LYMPHOMA-ASSOCIATED MIROUNGINE GAMMAHERPESVIRUS 3 IN NORTHERN ELEPHANT SEALS (MIROUNGA ANGUSTIROSTRIS). J Wildl Dis 2023; 59:121-127. [PMID: 36584338 DOI: 10.7589/jwd-d-22-00030] [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] [Received: 03/14/2022] [Accepted: 08/01/2022] [Indexed: 01/01/2023]
Abstract
Recently, a novel gammaherpesvirus, miroungine gammaherpesvirus 3 (MirGHV3), was described in two juvenile elephant seals (Mirounga angustirostris) with diffuse large B-cell lymphoma. We developed and validated a quantitative (q)PCR for rapid detection of MirGHV3 and investigated its potential association with lymphoma. We developed a duplex probe-hybridization qPCR with MirGHV3 DNA polymerase (pol) as the target gene. Each primer-probe combination was cross-validated against the others. Interference was not seen when they were run in the same well as a duplex assay. Twenty-three samples from seven northern elephant seals were tested using the duplex assay. Viral DNA was detected by the assay in 9 of 9 (100%) tissues affected by lymphoma and in 6 of 14 (43%) samples from tissues unaffected by lymphoma. There was a strong correlation between viral copies detected with each of the assays (P=0.0002). Viral load was significantly higher in tissues affected by lymphoma than in those unaffected (P<0.0001). Excluding the virus-negative samples, viral load was still significantly higher in tissues affected by lymphoma than in those unaffected (P=0.0004). This is consistent with a potential role of MirGHV3 in oncogenesis in northern elephant seals, although more studies are needed to determine this definitively. The qPCR developed has utility for further investigations of MirGHV3.
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Affiliation(s)
- Molly Horgan
- Department of Comparative, Diagnostic, and Population Medicine, University of Florida, College of Veterinary Medicine, Gainesville, Florida 32610, USA
| | - Margaret E Martinez
- The Marine Mammal Center, 2000 Bunker Road, Sausalito, California 94965, USA
| | - Linda L Archer
- Department of Comparative, Diagnostic, and Population Medicine, University of Florida, College of Veterinary Medicine, Gainesville, Florida 32610, USA
| | - Pádraig J Duignan
- The Marine Mammal Center, 2000 Bunker Road, Sausalito, California 94965, USA
| | - James F X Wellehan
- Department of Comparative, Diagnostic, and Population Medicine, University of Florida, College of Veterinary Medicine, Gainesville, Florida 32610, USA
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Martinez ME, Stacy NI, Wellehan JFX, Archer LL, Frasca S, Rios C, Trumbull EJ, Rivard M, Whitmer ER, Field CL, Duignan PJ. Diffuse large B cell lymphoma and a novel gammaherpesvirus in northern elephant seals Mirounga angustirostris. DISEASES OF AQUATIC ORGANISMS 2022; 149:59-70. [PMID: 35608510 DOI: 10.3354/dao03662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Two emaciated male northern elephant seal (NES) Mirounga angustirostris pups were admitted to The Marine Mammal Center (Sausalito, California, USA) and treated for malnutrition. Complete blood counts showed a progressive moderate to marked leukocytosis characterized by a predominance of large monomorphic mononuclear cells of probable lymphoid origin, frequently with flower-shaped nuclei. Both seals were euthanized due to suspected lymphoid neoplasia. At necropsy, most lymph nodes in both pups were markedly enlarged, some with distinct white nodules, the spleens were diffusely enlarged, and the intestinal mucosae were thickened. Histopathologic features consistent with disseminated large cell lymphoma were identified to varying degrees of severity in lymph nodes, bone marrow, liver, tonsils, spleen, liver, intestines, kidneys, lower urinary tract, and several other organs. Immunohistochemical staining of neoplastic cells was most consistent with B lymphocyte origin, with most cells staining positively for Pax 5 and CD20 with admixed small CD3-positive T lymphocytes and CD204-positive macrophages. PCR and sequencing identified a novel gammaherpesvirus, herein called miroungine gammaherpesvirus 3, from affected tissues. This virus is in a clade outside of named genera that utilize hosts in the suborder Caniformia. The present study is the first description of diffuse large B cell lymphoma with leukemic manifestation and concomitant detection of a novel gammaherpesvirus in free-living NESs. Further research regarding the prevalence of this new gammaherpesvirus and its associated pathogenesis in this species is indicated.
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Baines C, Lerebours A, Thomas F, Fort J, Kreitsberg R, Gentes S, Meitern R, Saks L, Ujvari B, Giraudeau M, Sepp T. Linking pollution and cancer in aquatic environments: A review. ENVIRONMENT INTERNATIONAL 2021; 149:106391. [PMID: 33515955 DOI: 10.1016/j.envint.2021.106391] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/23/2020] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
Due to the interconnectedness of aquatic ecosystems through the highly effective marine and atmospheric transport routes, all aquatic ecosystems are potentially vulnerable to pollution. Whilst links between pollution and increased mortality of wild animals have now been firmly established, the next steps should be to focus on specific physiological pathways and pathologies that link pollution to wildlife health deterioration. One of the pollution-induced pathologies that should be at the centre of attention in ecological and evolutionary research is cancer, as anthropogenic contamination has resulted in a rapid increase of oncogenic substances in natural habitats. Whilst wildlife cancer research is an emerging research topic, systematic reviews of the many case studies published over the recent decades are scarce. This research direction would (1) provide a better understanding of the physiological mechanisms connecting anthropogenic pollution to oncogenic processes in non-model organisms (reducing the current bias towards human and lab-animal studies in cancer research), and (2) allow us to better predict the vulnerability of different wild populations to oncogenic contamination. This article combines the information available within the scientific literature about cancer occurrences in aquatic and semi-aquatic species. For the first aim, we use available knowledge from aquatic species to suggest physiological mechanisms that link pollution and cancer, including main metabolic detoxification pathways, oxidative damage effects, infections, and changes to the microbiome. For the second aim, we determine which types of aquatic animals are more vulnerable to pollution-induced cancer, which types of pollution are mainly associated with cancer in aquatic ecosystems, and which types of cancer pollution causes. We also discuss the role of migration in exposing aquatic and semi-aquatic animals to different oncogenic pollutants. Finally, we suggest novel research avenues, including experimental approaches, analysis of the effects of pollutant cocktails and long-term chronic exposure to lower levels of pollutants, and the use of already published databases of gene expression levels in animals from differently polluted habitats.
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Affiliation(s)
- Ciara Baines
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia.
| | - Adelaide Lerebours
- LIttoral, ENvironnement et Sociétés (LIENSs), UMR7266, CNRS Université de La Rochelle, 2 rue Olympe de Gouges, 17042 La Rochelle Cedex, France
| | - Frederic Thomas
- CREEC/CREES, 911 Avenue Agropolis, BP 6450134394 Montpellier Cedex 5, France; MIVEGEC, UMR IRD/CNRS/UM 5290, 911 Avenue Agropolis, BP 6450134394 Montpellier Cedex 5, France
| | - Jerome Fort
- LIttoral, ENvironnement et Sociétés (LIENSs), UMR7266, CNRS Université de La Rochelle, 2 rue Olympe de Gouges, 17042 La Rochelle Cedex, France
| | - Randel Kreitsberg
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia
| | - Sophie Gentes
- LIttoral, ENvironnement et Sociétés (LIENSs), UMR7266, CNRS Université de La Rochelle, 2 rue Olympe de Gouges, 17042 La Rochelle Cedex, France
| | - Richard Meitern
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia
| | - Lauri Saks
- Estonian Marine Institute, Universty of Tartu, Mäealuse 14, 12618 Tallinn, Harju County, Estonia
| | - Beata Ujvari
- School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University, Waurn Ponds, VIC, Australia
| | - Mathieu Giraudeau
- LIttoral, ENvironnement et Sociétés (LIENSs), UMR7266, CNRS Université de La Rochelle, 2 rue Olympe de Gouges, 17042 La Rochelle Cedex, France; CREEC/CREES, 911 Avenue Agropolis, BP 6450134394 Montpellier Cedex 5, France; MIVEGEC, UMR IRD/CNRS/UM 5290, 911 Avenue Agropolis, BP 6450134394 Montpellier Cedex 5, France
| | - Tuul Sepp
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia
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4
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Peñín I, Figueroa-Cabañas ME, Guerrero-de la Rosa F, Soto-García LA, Álvarez-Martínez R, Flores-Morán A, Acevedo-Whitehouse K. Transcriptional Profiles of California Sea Lion Peripheral NK and CD +8 T Cells Reflect Ecological Regionalization and Infection by Oncogenic Viruses. Front Immunol 2019; 10:413. [PMID: 30915075 PMCID: PMC6422979 DOI: 10.3389/fimmu.2019.00413] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 02/15/2019] [Indexed: 12/12/2022] Open
Abstract
The California sea lion is one of the few wild mammals prone to develop cancer, particularly urogenital carcinoma (UGC), whose prevalence is currently estimated at 25% of dead adult sea lions stranded along the California coastline. Genetic factors, viruses and organochlorines have been identified as factors that increase the risk of occurrence of this pathology. Given that no cases of UGC have as yet been reported for the species along its distribution in Mexican waters, the potential relevance of contaminants for the development of urogenital carcinoma is highlighted even more as blubber levels of organochlorines are more than two orders of magnitude lower in the Gulf of California and Mexican Pacific than in California. In vitro studies have shown that organochlorines can modulate anti-viral and tumor-surveillance activities of NK and cytotoxic T-cells of marine mammals, but little is known about the activity of these effectors in live, free-living sea lions. Here, we examine leukocyte transcriptional profiles of free-ranging adult California sea lions for eight genes (Eomes, Granzyme B, Perforin, Ly49, STAT1, Tbx21, GATA3, and FoxP3) selected for their key role in anti-viral and tumor-surveillance, and investigate patterns of transcription that could be indicative of differences in ecological variables and exposure to two oncogenic viruses: sea lion type one gammaherpesvirus (OtHV-1) and sea lion papillomavirus type 1 (ZcPV-1) and systemic inflammation. We observed regional differences in the expression of genes related to Th1 responses and immune modulation, and detected clear patterns of differential regulation of gene expression in sea lions infected by genital papillomavirus compared to those infected by genital gammaherpesvirus or for simultaneous infections, similar to what is known about herpesvirus and papillomavirus infections in humans. Our study is a first approach to profile the transcriptional patterns of key immune effectors of free-ranging California sea lions and their association with ecological regions and oncogenic viruses. The observed results add insight to our understanding of immune competence of marine mammals, and may help elucidate the marked difference in the number of cases of urogenital carcinoma in sea lions from US waters and other areas of their distribution.
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Affiliation(s)
- Ignacio Peñín
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Mónica E Figueroa-Cabañas
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Fabiola Guerrero-de la Rosa
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Luis A Soto-García
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Roberto Álvarez-Martínez
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Adriana Flores-Morán
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico
| | - Karina Acevedo-Whitehouse
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Santiago de Queretaro, Mexico.,The Marine Mammal Center, Sausalito, CA, United States
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Abstract
Cancer is ubiquitous in wildlife, affecting animals from bivalves to pachyderms and cetaceans. Reports of increasing frequency demonstrate that neoplasia is associated with substantial mortality in wildlife species. Anthropogenic activities and global weather changes are shaping new geographical limitations for many species, and alterations in living niches are associated with visible examples of genetic bottlenecks, toxin exposures, oncogenic pathogens, stress and immunosuppression, which can all contribute to cancers in wild species. Nations that devote resources to monitoring the health of wildlife often do so for human-centric reasons, including for the prediction of the potential for zoonotic disease, shared contaminants, chemicals and medications, and for observing the effect of exposure from crowding and loss of habitat. Given the increasing human footprint on land and in the sea, wildlife conservation should also become a more important motivating factor. Greater attention to the patterns of the emergence of wildlife cancer is imperative because growing numbers of species are existing at the interface between humans and the environment, making wildlife sentinels for both animal and human health. Therefore, monitoring wildlife cancers could offer interesting and novel insights into potentially unique non-age-related mechanisms of carcinogenesis across species.
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Affiliation(s)
- Patricia A Pesavento
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA.
| | - Dalen Agnew
- Veterinary Diagnostic Laboratory, Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
| | - Michael K Keel
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Kevin D Woolard
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA
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6
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MAMMARY FIBROADENOMATOUS HYPERPLASIA IN A JUVENILE CALIFORNIA SEA LION ( ZALOPHUS CALIFORNIANUS). J Zoo Wildl Med 2018; 49:806-809. [PMID: 30212341 DOI: 10.1638/2017-0186.1] [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: 11/21/2022] Open
Abstract
A juvenile female California sea lion ( Zalophus californianus) presented with a firm subcutaneous mass in the right caudoventral pelvic region, measuring approximately 15 × 15 cm, and edema in the right hind flipper. The initial diagnostic workup included an ultrasound, blood analysis, and fine-needle aspirate of the mass under manual restraint. While the blood analysis was within normal limits, the ultrasound revealed a large discrete hyperechoic homogeneous mass with anastomosing hypoechoic fluid pockets that, when aspirated, was suggestive of a reactive lymph node. Short-term empiric antibiotic therapy prescribed to address possible lymphadenitis yielded no response, and edema of the right hind flipper and perianal region worsened. The sea lion was anesthetized to facilitate a more thorough exam, repeat blood analysis, obtain survey radiographs, evaluate with ultrasound, and perform biopsy of mass. The thoracic radiographs were normal; however, the large radiopaque mass was observed cranial to the pelvis on lateral abdominal view and appeared solitary on ultrasound. An exploratory surgery was performed to completely excise the mass. On histopathologic review, the mass demonstrated diffuse fibrous hyperplasia of lobular ducts of the mammary gland and mild mastitis, characterizing it as a mammary fibroadenoma. The surgical wound healed within 6 wk, and there was no recurrence of mammary hyperplasia.
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7
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PAROTID CARCINOMA IN A FREE-RANGING CALIFORNIA SEA LION ( ZALOPHUS CALIFORNIANUS). J Zoo Wildl Med 2018; 49:824-827. [PMID: 30212325 DOI: 10.1638/2017-0130.1] [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: 11/21/2022] Open
Abstract
A free-ranging juvenile California sea lion ( Zalophus californianus) stranded on the coast of Vancouver, British Columbia, with signs of lethargy and emaciation in April 2016. An asymmetrical skull with a prominent superficial cervical lymph node was found on initial assessment. Fine-needle aspirates and biopsies of the lymph node were consistent with neoplasia and the animal was humanely euthanized and presented for necropsy. A metastatic parotid gland adenocarcinoma was diagnosed with regional lymph node and pulmonary metastases. Local invasion of contiguous skeletal muscle, bone, ear, and tonsils was extensive and likely accounted for the unilateral craniofacial deformity. Neoplasia of nonurogenital origin in juvenile California sea lions are reported infrequently. This is the first case of a parotid carcinoma in a California sea lion.
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8
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Luff JA, Burns RE, Mader M, Priest KD, Tuttle AD. Cutaneous squamous cell carcinoma associated with Zalophus californianus papillomavirus 1 in a California sea lion. J Vet Diagn Invest 2018; 30:572-575. [PMID: 29629648 DOI: 10.1177/1040638718769702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Papillomaviruses (PVs) are found in many species and infect epithelial cells at both mucosal and cutaneous sites. PVs are generally species-specific and cause benign epithelial proliferations, often forming papillomas or plaques. Rarely, these infections can persist, allowing progression to in situ and invasive cancers. We describe herein a case of multiple cutaneous pigmented plaques from a California sea lion ( Zalophus californianus) that progressed to in situ and invasive squamous cell carcinoma (SCC). The lesions were characterized by epithelial hyperplasia, hyperkeratosis, and hypergranulosis that bordered more dysplastic areas, and, at one site, bordered an invasive SCC. Immunohistochemistry for papillomavirus antigen revealed strong nuclear immunoreactivity within keratinocytes in the hyperplastic epidermis. PCR was performed using degenerate and specific primers to detect papillomavirus DNA. Specific primers were used to amplify Zalophus californianus papillomavirus 1 (ZcPV-1), the only sea lion papillomavirus known to date. We detected ZcPV-1 DNA within the pigmented plaque, and in both in situ and invasive SCC samples.
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Affiliation(s)
- Jennifer A Luff
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Luff, Mader).,Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT (Burns, Priest).,Mystic Aquarium, Department of Animal Care, Mystic, CT (Tuttle)
| | - Rachel E Burns
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Luff, Mader).,Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT (Burns, Priest).,Mystic Aquarium, Department of Animal Care, Mystic, CT (Tuttle)
| | - Michelle Mader
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Luff, Mader).,Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT (Burns, Priest).,Mystic Aquarium, Department of Animal Care, Mystic, CT (Tuttle)
| | - Kara D Priest
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Luff, Mader).,Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT (Burns, Priest).,Mystic Aquarium, Department of Animal Care, Mystic, CT (Tuttle)
| | - Allison D Tuttle
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Luff, Mader).,Department of Pathobiology and Veterinary Science, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT (Burns, Priest).,Mystic Aquarium, Department of Animal Care, Mystic, CT (Tuttle)
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9
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Ní Leathlobhair M, Gulland FMD, Murchison EP. No evidence for clonal transmission of urogenital carcinoma in California sea lions ( Zalophus californianus). Wellcome Open Res 2017; 2:46. [PMID: 28948233 PMCID: PMC5527528 DOI: 10.12688/wellcomeopenres.11483.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2017] [Indexed: 12/03/2022] Open
Abstract
Urogenital carcinoma is a highly metastatic cancer affecting California sea lions (
Zalophus californianus). The disease has high prevalence amongst stranded animals, and is one of the most commonly observed cancers in wildlife. The genital localisation of primary tumours suggests the possibility that coital transmission of an infectious agent could underlie this disease. Otarine herpesvirus type 1 has been associated with lesions, however a causative role for this virus has not been confirmed. We investigated the possibility that urogenital carcinoma might be clonally transmissible, spread by the direct transfer of cancer cells. Analysis of sequences at the mitochondrial DNA control region in seven matched tumour and host pairs confirmed that tumour genotypes were identical to those of their matched hosts and did not show similarity with tumours from other individuals. Thus our findings suggest that urogenital carcinoma in California sea lions is not clonally transmitted, but rather arises from transformed host cells.
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Affiliation(s)
- Máire Ní Leathlobhair
- Transmissible Cancer Group, Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
| | | | - Elizabeth P Murchison
- Transmissible Cancer Group, Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
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10
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Munang'andu HM, Mugimba KK, Byarugaba DK, Mutoloki S, Evensen Ø. Current Advances on Virus Discovery and Diagnostic Role of Viral Metagenomics in Aquatic Organisms. Front Microbiol 2017; 8:406. [PMID: 28382024 PMCID: PMC5360701 DOI: 10.3389/fmicb.2017.00406] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 02/27/2017] [Indexed: 12/20/2022] Open
Abstract
The global expansion of the aquaculture industry has brought with it a corresponding increase of novel viruses infecting different aquatic organisms. These emerging viral pathogens have proved to be a challenge to the use of traditional cell-cultures and immunoassays for identification of new viruses especially in situations where the novel viruses are unculturable and no antibodies exist for their identification. Viral metagenomics has the potential to identify novel viruses without prior knowledge of their genomic sequence data and may provide a solution for the study of unculturable viruses. This review provides a synopsis on the contribution of viral metagenomics to the discovery of viruses infecting different aquatic organisms as well as its potential role in viral diagnostics. High throughput Next Generation sequencing (NGS) and library construction used in metagenomic projects have simplified the task of generating complete viral genomes unlike the challenge faced in traditional methods that use multiple primers targeted at different segments and VPs to generate the entire genome of a novel virus. In terms of diagnostics, studies carried out this far show that viral metagenomics has the potential to serve as a multifaceted tool able to study and identify etiological agents of single infections, co-infections, tissue tropism, profiling viral infections of different aquatic organisms, epidemiological monitoring of disease prevalence, evolutionary phylogenetic analyses, and the study of genomic diversity in quasispecies viruses. With sequencing technologies and bioinformatics analytical tools becoming cheaper and easier, we anticipate that metagenomics will soon become a routine tool for the discovery, study, and identification of novel pathogens including viruses to enable timely disease control for emerging diseases in aquaculture.
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Affiliation(s)
- Hetron M. Munang'andu
- Section of Aquatic Medicine and Nutrition, Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life SciencesOslo, Norway
| | - Kizito K. Mugimba
- Section of Aquatic Medicine and Nutrition, Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life SciencesOslo, Norway
- Department of Biotechnical and Diagnostic Sciences, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere UniversityKampala, Uganda
| | - Denis K. Byarugaba
- Department of Biotechnical and Diagnostic Sciences, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere UniversityKampala, Uganda
| | - Stephen Mutoloki
- Section of Aquatic Medicine and Nutrition, Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life SciencesOslo, Norway
| | - Øystein Evensen
- Section of Aquatic Medicine and Nutrition, Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life SciencesOslo, Norway
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11
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Browning HM, Gulland FMD, Hammond JA, Colegrove KM, Hall AJ. Common cancer in a wild animal: the California sea lion (Zalophus californianus) as an emerging model for carcinogenesis. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0228. [PMID: 26056370 DOI: 10.1098/rstb.2014.0228] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Naturally occurring cancers in non-laboratory species have great potential in helping to decipher the often complex causes of neoplasia. Wild animal models could add substantially to our understanding of carcinogenesis, particularly of genetic and environmental interactions, but they are currently underutilized. Studying neoplasia in wild animals is difficult and especially challenging in marine mammals owing to their inaccessibility, lack of exposure history, and ethical, logistical and legal limits on experimentation. Despite this, California sea lions (Zalophus californianus) offer an opportunity to investigate risk factors for neoplasia development that have implications for terrestrial mammals and humans who share much of their environment and diet. A relatively accessible California sea lion population on the west coast of the USA has a high prevalence of urogenital carcinoma and is regularly sampled during veterinary care in wildlife rehabilitation centres. Collaborative studies have revealed that genotype, persistent organic pollutants and a herpesvirus are all associated with this cancer. This paper reviews research to date on the epidemiology and pathogenesis of urogenital carcinoma in this species, and presents the California sea lion as an important and currently underexploited wild animal model of carcinogenesis.
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Affiliation(s)
- Helen M Browning
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews KY16 8LB, UK
| | | | | | - Kathleen M Colegrove
- Zoological Pathology Program, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Maywood, IL 60153, USA
| | - Ailsa J Hall
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews KY16 8LB, UK
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12
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Schiffman JD, Breen M. Comparative oncology: what dogs and other species can teach us about humans with cancer. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0231. [PMID: 26056372 DOI: 10.1098/rstb.2014.0231] [Citation(s) in RCA: 237] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Over 1.66 million humans (approx. 500/100,000 population rate) and over 4.2 million dogs (approx. 5300/100,000 population rate) are diagnosed with cancer annually in the USA. The interdisciplinary field of comparative oncology offers a unique and strong opportunity to learn more about universal cancer risk and development through epidemiology, genetic and genomic investigations. Working across species, researchers from human and veterinary medicine can combine scientific findings to understand more quickly the origins of cancer and translate these findings to novel therapies to benefit both human and animals. This review begins with the genetic origins of canines and their advantage in cancer research. We next focus on recent findings in comparative oncology related to inherited, or genetic, risk for tumour development. We then detail the somatic, or genomic, changes within tumours and the similarities between species. The shared cancers between humans and dogs that we discuss include sarcoma (osteosarcoma, soft tissue sarcoma, histiocytic sarcoma, hemangiosarcoma), haematological malignancies (lymphoma, leukaemia), bladder cancer, intracranial neoplasms (meningioma, glioma) and melanoma. Tumour risk in other animal species is also briefly discussed. As the field of genomics advances, we predict that comparative oncology will continue to benefit both humans and the animals that live among us.
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Affiliation(s)
- Joshua D Schiffman
- Department of Pediatrics and Oncological Sciences, Primary Children's Hospital, Intermountain Healthcare, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Matthew Breen
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, Center for Comparative Medicine and Translational Research, Center for Human Health and the Environment, Cancer Genetics, UNC Lineberger Comprehensive Cancer Center, North Carolina State University, Raleigh, NC, USA
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Barragán-Vargas C, Montano-Frías J, Ávila Rosales G, Godínez-Reyes CR, Acevedo-Whitehouse K. Transformation of the genital epithelial tract occurs early in California sea lion development. ROYAL SOCIETY OPEN SCIENCE 2016; 3:150419. [PMID: 27069641 PMCID: PMC4821252 DOI: 10.1098/rsos.150419] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 02/12/2016] [Indexed: 05/08/2023]
Abstract
An unusually high prevalence of metastatic urogenital carcinoma has been observed in free-ranging California sea lions stranded off the coast of California in the past two decades. No cases have been reported for sea lions in the relatively unpolluted Gulf of California. We investigated occurrence of genital epithelial transformation in 60 sea lions (n=57 pups and 3 adult females) from the Gulf of California and examined whether infection by a viral pathogen previously found to be associated with urogenital carcinoma accounted for such alterations. We also explored the contribution of MHC class II gene expression on transformation. Cellular alterations, such as squamous cell atypia (ASC), atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions were observed in 42% of the pups and in 67% of the adult females. Normal genital epithelium was more common in male than female pups. ASC was five times more likely to occur in older pups. Epithelial alterations were unrelated to infection by the potentially oncogenic otarine type I gammaherpesvirus (OtHV-1), but ASCUS was more common in pups with marked and severe inflammation. Expression of MHC class II DRB loci (Zaca DRB-D) by peripheral antigen-presenting leucocytes showed a slightly 'protective' effect for ASC. We propose that transformation of the California sea lion genital epithelium is relatively common in young animals, increases with age and is probably the result of infection by an unidentified pathogen. Expression of a specific MHC class II gene, suggestive of presentation of specific antigenic peptides to immune effectors, appears to lower the risk of transformation. Our study provides the first evidence that epithelial transformation of the California sea lion genital tract is relatively common, even from an early age, and raises questions regarding differences in sea lion cancer-detection and -repair success between geographical regions.
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Affiliation(s)
- Cecilia Barragán-Vargas
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Avenida de las Ciencias S/N, Queretaro 76230, Mexico
| | - Jorge Montano-Frías
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Avenida de las Ciencias S/N, Queretaro 76230, Mexico
| | - Germán Ávila Rosales
- Department of Pathology, Instituto Mexicano del Seguro Social, Queretaro 76000, Mexico
| | - Carlos R. Godínez-Reyes
- Cabo Pulmo National Park, Comisión Nacional de Áreas Naturales Protegidas, SEMARNAT, La Ribera, BCS, Mexico
| | - Karina Acevedo-Whitehouse
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Autonomous University of Queretaro, Avenida de las Ciencias S/N, Queretaro 76230, Mexico
- The Marine Mammal Center, 2000 Bunker Road, Sausalito, CA 94965, USA
- Sea Lion Cancer Consortium. http://www.smru.st-andrews.ac.uk/slicc
- Author for correspondence: Karina Acevedo-Whitehouse e-mail:
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Vickers TW, Clifford DL, Garcelon DK, King JL, Duncan CL, Gaffney PM, Boyce WM. Pathology and Epidemiology of Ceruminous Gland Tumors among Endangered Santa Catalina Island Foxes (Urocyon littoralis catalinae) in the Channel Islands, USA. PLoS One 2015; 10:e0143211. [PMID: 26618759 PMCID: PMC4664485 DOI: 10.1371/journal.pone.0143211] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 11/02/2015] [Indexed: 01/29/2023] Open
Abstract
In this study, we examined the prevalence, pathology, and epidemiology of tumors in free-ranging island foxes occurring on three islands in the California Channel Islands, USA. We found a remarkably high prevalence of ceruminous gland tumors in endangered foxes (Urocyon littoralis catalinae) occurring on Santa Catalina Island (SCA)—48.9% of the dead foxes examined from 2001–2008 had tumors in their ears, and tumors were found in 52.2% of randomly-selected mature (≥ 4 years) foxes captured in 2007–2008, representing one of the highest prevalences of tumors ever documented in a wildlife population. In contrast, no tumors were detected in foxes from San Nicolas Island or San Clemente Island, although ear mites (Otodectes cynotis), a predisposing factor for ceruminous gland tumors in dogs and cats, were highly prevalent on all three islands. On SCA, otitis externa secondary to ear mite infection was highly correlated with ceruminous gland hyperplasia (CGH), and tumors were significantly associated with the severity of CGH, ceruminous gland dysplasia, and age group (older foxes). We propose a conceptual model for the formation of ceruminous gland tumors in foxes on SCA that is based on persistent, ubiquitous infection with ear mites, and an innate, over exuberant inflammatory and hyperplastic response of SCA foxes to these mites. Foxes on SCA are now opportunistically treated with acaricides in an attempt to reduce mite infections and the morbidity and mortality associated with this highly prevalent tumor.
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Affiliation(s)
- T. Winston Vickers
- Institute for Wildlife Studies, Arcata, California, United States of America
- Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- * E-mail: (TWV), (WMB)
| | - Deana L. Clifford
- Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- Wildlife Investigations Lab, California Department of Fish and Wildlife, Rancho Cordova, California, United States of America
| | - David K. Garcelon
- Institute for Wildlife Studies, Arcata, California, United States of America
| | - Julie L. King
- Catalina Island Conservancy, Avalon, California, United States of America
| | - Calvin L. Duncan
- Catalina Island Conservancy, Avalon, California, United States of America
| | - Patricia M. Gaffney
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- Departments of Pathology and Medicine, University of California San Diego, San Diego, California, United States of America
| | - Walter M. Boyce
- Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- * E-mail: (TWV), (WMB)
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15
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Lair S, Measures LN, Martineau D. Pathologic Findings and Trends in Mortality in the Beluga (Delphinapterus leucas) Population of the St Lawrence Estuary, Quebec, Canada, From 1983 to 2012. Vet Pathol 2015; 53:22-36. [PMID: 26374277 DOI: 10.1177/0300985815604726] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
An isolated population of beluga (Delphinapterus leucas) inhabits the St Lawrence Estuary, Quebec, Canada. This population has failed to recover despite the prohibition of hunting >30 years ago, suggesting the presence of other limiting factors. The authors summarize the reported causes of death and propose risk factors to explain the lack of recovery of this population. From 1983 to 2012, a total of 472 beluga were found stranded. Complete necropsies were carried out on 222 beluga, including 178 adults, 25 juveniles, and 19 newborn calves. Infectious diseases, the most prevalent cause of mortality in this population, accounted for the death of one-third of all beluga (32%). Verminous pneumonia was the cause of mortality of 13 juvenile beluga (52% of juvenile beluga). A total of 39 malignant neoplasms, diagnosed in 35 beluga, caused the death of 31 beluga (20% of beluga >19 years old). Median age at diagnosis of cancer was 48 years (range, 30-61 years). Dystocia and postpartum complications were the cause of death in 18 beluga, accounting for 19% of the females >19 years old examined. The occurrence of parturition-associated complications, as well as mortality of calves <1 year old, have increased recently in this population and may be the probable cause of the recent decrease in the size of this population. One of the hypotheses proposed to explain the unusually high occurrence of some of the pathologic conditions observed in this population is chronic exposure to environmental contaminants.
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Affiliation(s)
- S Lair
- Centre québécois sur la santé des animaux sauvages / Canadian Wildlife Health Cooperative, Département de sciences cliniques, Faculté de médecine vétérinaire, Université de Montréal, St Hyacinthe, Canada
| | - L N Measures
- Fisheries and Oceans Canada, Maurice Lamontagne Institute, Mont-Joli, Canada
| | - D Martineau
- Département de pathologie et microbiologie, Faculté de médecine vétérinaire, Université de Montréal, St Hyacinthe, Canada
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16
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Browning HM, Acevedo-Whitehouse K, Gulland FMD, Hall AJ, Finlayson J, Dagleish MP, Billington KJ, Colegrove K, Hammond JA. Evidence for a genetic basis of urogenital carcinoma in the wild California sea lion. Proc Biol Sci 2015; 281:20140240. [PMID: 25339718 PMCID: PMC4213630 DOI: 10.1098/rspb.2014.0240] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Although neoplasia is a major cause of mortality in humans and domestic animals, it has rarely been described in wildlife species. One of the few examples is a highly prevalent urogenital carcinoma in California sea lions (CSLs). Although the aetiology of this carcinoma is clearly multifactorial, inbreeding depression, as estimated using levels of microsatellite multilocus heterozygosity, is identified as predictive for this neoplasia. On further analysis, this relationship appears to be largely driven by one marker, suggesting that a single locus might be associated with the occurrence of this disease in CSLs. In a case–control study, carcinoma was significantly associated with homozygosity at the Pv11 microsatellite locus. Pv11 was mapped to intron 9 of the heparanase 2 gene (HPSE2) locus, a very large gene encoding heparanase 2, which in humans is associated with multiple carcinomas. Correspondingly, immunohistochemical labelling in tissues was present in carcinoma cases within a single homozygous Pv11 genotype. To our knowledge, this is the first report of an individual locus being associated with cancer in any wildlife species. This adds emphasis to the study of HPSE2 in other species, including humans and will guide future studies on this sentinel species that shares much of its diet and environment with humans
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Affiliation(s)
- Helen M Browning
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Fife, UK
| | | | | | - Ailsa J Hall
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Fife, UK
| | - Jeanie Finlayson
- The Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, UK
| | - Mark P Dagleish
- The Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, UK
| | | | - Kathleen Colegrove
- Zoological Pathology Program, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Maywood, IL, USA
| | - John A Hammond
- Pirbright Laboratory, The Pirbright Institute, Surrey, UK
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17
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Wright EP, Waugh LF, Goldstein T, Freeman KS, Kelly TR, Wheeler EA, Smith BR, Gulland FMD. Evaluation of viruses and their association with ocular lesions in pinnipeds in rehabilitation. Vet Ophthalmol 2014; 18 Suppl 1:148-59. [DOI: 10.1111/vop.12235] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Erin P. Wright
- Royal Veterinary College; University of London; London NW1 0TU UK
- Institute of Zoology; Zoological Society of London; London NW1 4RY UK
| | - Lynnette F. Waugh
- Veterinary Medical Teaching Hospital; School of Veterinary Medicine; University of California Davis; Davis CA 95616 USA
| | - Tracey Goldstein
- Wildlife Health Center; School of Veterinary Medicine; University of California, Davis; Davis CA 95616 USA
| | - Katie S. Freeman
- Department of Clinical Sciences; College of Veterinary Medicine; Colorado State University; Fort Collins CO 80523 USA
| | - Terra R. Kelly
- Wildlife Health Center; School of Veterinary Medicine; University of California, Davis; Davis CA 95616 USA
| | - Elizabeth A. Wheeler
- The Marine Mammal Center; 2000 Bunker Road Fort Cronkhite Sausalito CA 94965 USA
| | - Brett R. Smith
- Wildlife Health Center; School of Veterinary Medicine; University of California, Davis; Davis CA 95616 USA
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18
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Dagleish M, Barrows M, Maley M, Killick R, Finlayson J, Goodchild R, Valentine A, Saunders R, Willoughby K, Smith K, Stidworthy M. The First Report of Otarine Herpesvirus-1-Associated Urogenital Carcinoma in a South American Fur Seal (Arctocephalus australis). J Comp Pathol 2013; 149:119-25. [DOI: 10.1016/j.jcpa.2012.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 09/10/2012] [Accepted: 10/16/2012] [Indexed: 11/30/2022]
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Miller S, Colitz CMH, St Leger J, Dubielzig R. A retrospective survey of the ocular histopathology of the pinniped eye with emphasis on corneal disease. Vet Ophthalmol 2012; 16:119-29. [PMID: 22812701 DOI: 10.1111/j.1463-5224.2012.01040.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE A retrospective review of globes from 70 pinnipeds submitted to the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) describing the type and frequency of ocular disease. ANIMALS STUDIED The study included 50 California sea lions, four animals listed only as 'sea lion', nine Northern elephant seals, five harbor seals, 1 Northern fur seal, and 1 Hooded seal. PROCEDURES Globes were classified by microscopic findings. Categories were not mutually exclusive. RESULTS The largest category was corneal disease (63 globes from 40 pinnipeds). The second largest was cataractous changes (35 globes from 23 pinnipeds). Additional ocular diseases included traumatic ocular injuries (nine globes from eight animals), phthisis bulbi (nine globes from eight pinnipeds), neoplasia (nine globes from six adult California sea lions), amyloid deposition in the corneal stroma, ciliary body, or both locations (five globes from four pinnipeds), and fungal disease (three globes from two pinnipeds). Pinnipeds with corneal disease were further categorized: stromal pathology (39 globes from 27 pinnipeds); epithelial pathology (37 globes from 27 pinnipeds); Descemet's pathology (11 globes from eight pinnipeds); endothelial attenuation or absence (33 globes from 22 pinnipeds); presence of retrocorneal membranes (15 globes from 10 pinnipeds); anterior synechia (eight globes from six animals), and keratitis (seven globes from five pinnipeds). CONCLUSIONS This is the first report of ocular amyloid in pinniped eyes. All cases of neoplasia were in a pattern suggesting metastatic disease. In this study, there was a higher prevalence of ocular disease in captive pinnipeds, particularly in the posterior cornea.
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Affiliation(s)
- Sarah Miller
- School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA.
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20
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Rehtanz M, Bossart GD, Fair PA, Reif JS, Ghim SJ, Jenson AB. Papillomaviruses and herpesviruses: who is who in genital tumor development of free-ranging Atlantic bottlenose dolphins (Tursiops truncatus)? Vet Microbiol 2012; 160:297-304. [PMID: 22763174 DOI: 10.1016/j.vetmic.2012.05.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 05/29/2012] [Accepted: 05/31/2012] [Indexed: 10/28/2022]
Abstract
The number of studies addressing neoplasia in marine mammals has recently increased, giving rise to concern whether such lesions could be reflective of an emerging infectious disease. Eight species-specific viruses, seven papillomaviruses (PVs) and two herpesviruses (HVs) have separately been shown to be associated with genital tumors in Atlantic bottlenose dolphins (Tursiops truncatus, Tt): TtPV1-6, as well as HVs provisionally assigned the names DeHV4 and -5 (Delphinid HVs). A definite causal role of these viruses in cell transformation remains to be demonstrated. Concurrent PV- and HV-infection has never been reported in marine mammals. DNA extractions from biopsies of genital tumors derived from 15 free-ranging Atlantic bottlenose dolphins were selected for molecular examination. Polymerase chain reaction (PCR) analyses revealed the presence of DeHV4, while a serological screening using an antibody-based TtPV enzyme-linked immunosorbent assay (ELISA) demonstrated previous and/or current infection of the HV-positive dolphins with at least one TtPV type. Therefore, care must be taken when drawing conclusions about viral causalities in tumor development, since the "hit and run" and other mechanisms have been described for types of both viral families. This study presents the first evidence of marine mammals having a history of PV- as well as HV-infection and discusses the disputed effects of viral co-infection.
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Affiliation(s)
- Manuela Rehtanz
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA.
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21
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Rivera R, Robles-Sikisaka R, Hoffman EM, Stacy BA, Jensen ED, Nollens HH, Wellehan JFX. Characterization of a novel papillomavirus species (ZcPV1) from two California sea lions (Zalophus californianus). Vet Microbiol 2011; 155:257-66. [PMID: 22005176 DOI: 10.1016/j.vetmic.2011.09.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 09/16/2011] [Accepted: 09/23/2011] [Indexed: 12/24/2022]
Abstract
A seven-year old California sea lion (Zalophus californianus) presented with focally extensive, bilaterally symmetric, proliferative axillary skin lesions and preputial lesions. A second California sea lion in the same population presented with similar proliferative lesions on the underside of the tail. Histopathology revealed epidermal hyperplasia with severe hyperkeratosis, with proliferating keratinocytes forming broad, branching pegs that extended into the dermis. Pan-papillomaviral consensus PCR was used to obtain initial E1 sequence template and the complete genome was determined using a combination of rolling circle amplification and specific-primer PCR. Analysis revealed a novel papillomavirus, Zalophus californianus papillomavirus 1 (ZcPV1), with seven open reading frames encoding five early proteins (E6, E7, E1, E2 and E4) and two late proteins (L1 and L2). Phylogenetic analysis revealed that (ZcPV1) is most closely related to Equine papillomavirus 1 (EcPV1) in the genus Zetapapillomavirus, and Canine papillomaviruses 3 and 4 (CPV3, CPV4) in the genus Chipapillomavirus. The lesions regressed without intervention over a period of several months.
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Affiliation(s)
- Rebecca Rivera
- Hubbs-SeaWorld Research Institute, Center for Marine Veterinary Virology, 2595 Ingraham St., San Diego, CA 92109, USA.
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22
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Abstract
California sea lions are one of the major marine mammal species along the Pacific coast of North America. Sea lions are susceptible to a wide variety of viruses, some of which can be transmitted to or from terrestrial mammals. Using an unbiased viral metagenomic approach, we surveyed the fecal virome in California sea lions of different ages and health statuses. Averages of 1.6 and 2.5 distinct mammalian viral species were shed by pups and juvenile sea lions, respectively. Previously undescribed mammalian viruses from four RNA virus families (Astroviridae, Picornaviridae, Caliciviridae, and Reoviridae) and one DNA virus family (Parvoviridae) were characterized. The first complete or partial genomes of sapeloviruses, sapoviruses, noroviruses, and bocavirus in marine mammals are reported. Astroviruses and bocaviruses showed the highest prevalence and abundance in California sea lion feces. The diversity of bacteriophages was higher in unweaned sea lion pups than in juveniles and animals in rehabilitation, where the phage community consisted largely of phages related to the family Microviridae. This study increases our understanding of the viral diversity in marine mammals, highlights the high rate of enteric viral infections in these highly social carnivores, and may be used as a baseline viral survey for comparison with samples from California sea lions during unexplained disease outbreaks.
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Abstract
The long-term consequences of climate change and potential environmental degradation are likely to include aspects of disease emergence in marine plants and animals. In turn, these emerging diseases may have epizootic potential, zoonotic implications, and a complex pathogenesis involving other cofactors such as anthropogenic contaminant burden, genetics, and immunologic dysfunction. The concept of marine sentinel organisms provides one approach to evaluating aquatic ecosystem health. Such sentinels are barometers for current or potential negative impacts on individual- and population-level animal health. In turn, using marine sentinels permits better characterization and management of impacts that ultimately affect animal and human health associated with the oceans. Marine mammals are prime sentinel species because many species have long life spans, are long-term coastal residents, feed at a high trophic level, and have unique fat stores that can serve as depots for anthropogenic toxins. Marine mammals may be exposed to environmental stressors such as chemical pollutants, harmful algal biotoxins, and emerging or resurging pathogens. Since many marine mammal species share the coastal environment with humans and consume the same food, they also may serve as effective sentinels for public health problems. Finally, marine mammals are charismatic megafauna that typically stimulate an exaggerated human behavioral response and are thus more likely to be observed.
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Colegrove KM, Gulland FMD, Naydan DK, Lowenstine LJ. The normal genital tract of the female California sea lion (Zalophus californianus): cyclic changes in histomorphology and hormone receptor distribution. Anat Rec (Hoboken) 2010; 292:1801-17. [PMID: 19768749 DOI: 10.1002/ar.21009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Changes in reproductive tract histomorphology, and estrogen (ERalpha) and progesterone receptor (PR) expression throughout the breeding cycle were evaluated in free-ranging stranded female California sea lions (Zalophus californianus). Hormone receptor expression in the ovaries, uterus, cervix, and vagina was evaluated using an immunohistochemical technique with monoclonal antibodies. During a large portion of the cycle, ovaries contained both a corpora lutea (CL) and follicles in varying stages of development. In the periods of pupping and estrus during June and July, and in the spring morphologic features of the endometrium suggested estrogen influence. There were areas of squamous differentiation in the pseudostratified columnar epithelium of the cervix and vagina in some animals during estrus and in the spring. Estrogen receptor immunohistochemical scores were highest during pupping and estrus and in the spring and lowest during embryonic diapause. Cyclic changes in uterine PR expression throughout the cycle were minimal. Both ERalpha and PR were expressed in epithelial and stromal cells throughout the cervix and vagina, however, receptor expression was typically higher in the stroma. Stromal cell hormone receptors may play an important role in epithelial responses to circulating sex hormones. The results of this investigation add to the general knowledge of California sea lion reproduction and establish baseline information on reproductive tract hormone receptors that will aid in determining the factors involved in urogenital cancer development in sea lions.
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25
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Acevedo-Whitehouse K, Duffus ALJ. Effects of environmental change on wildlife health. Philos Trans R Soc Lond B Biol Sci 2010; 364:3429-38. [PMID: 19833653 DOI: 10.1098/rstb.2009.0128] [Citation(s) in RCA: 194] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Environmental change has negatively affected most biological systems on our planet and is becoming of increasing concern for the well-being and survival of many species. At an organism level, effects encompass not only endocrine disruptions, sex-ratio changes and decreased reproductive parameters, but also include teratogenic and genotoxic effects, immunosuppression and other immune-system impairments that can lead directly to disease or increase the risk of acquiring disease. Living organisms will strive to maintain health by recognizing and resolving abnormal situations, such as the presence of invading microorganisms or harmful peptides, abnormal cell replication and deleterious mutations. However, fast-paced environmental changes may pose additional pressure on immunocompetence and health maintenance, which may seriously impact population viability and persistence. Here, we outline the importance of a functional immune system for survival and examine the effects that exposure to a rapidly changing environment might exert on immunocompetence. We then address the various levels at which anthropogenic environmental change might affect wildlife health and identify potential deficits in reproductive parameters that might arise owing to new immune challenges in the context of a rapidly changing environment. Throughout the paper, a series of examples and case studies are used to illustrate the impact of environmental change on wildlife health.
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26
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Affiliation(s)
- Kathleen M. Colegrove
- Zoological Pathology Program, College of Veterinary Medicine, University of Illinois at Urbana-Champaign
| | - Linda J. Lowenstine
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis
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27
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Abstract
Until recently, cancer in wildlife was not considered to be a conservation concern. However, with the identification of Tasmanian devil facial tumour disease, sea turtle fibropapillomatosis and sea lion genital carcinoma, it has become apparent that neoplasia can be highly prevalent and have considerable effects on some species. It is also clear that anthropogenic activities contribute to the development of neoplasia in wildlife species, such as beluga whales and bottom-dwelling fish, making them sensitive sentinels of disturbed environments.
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Affiliation(s)
- Denise McAloose
- Pathology and Disease Investigation, Global Health Program, Wildlife Conservation Society, 2300 Southern Boulevard, Bronx, New York, New York 10460, USA.
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28
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Colegrove KM, Gullanda FMD, Naydan DK, Lowenstine LJ. Tumor Morphology and Immunohistochemical Expression of Estrogen Receptor, Progesterone Receptor, p53, and Ki67 in Urogenital Carcinomas of California Sea Lions (Zalophus californianus). Vet Pathol 2009; 46:642-55. [DOI: 10.1354/vp.08-vp-0214-c-fl] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Metastatic carcinoma of urogenital origin is a common cause of mortality in free-ranging California sea lions (Zalophus californianus). The etiology of this cancer is likely multifactorial, with viral infection, genetic factors, and exposure to environmental organochlorine contaminants possible contributing factors. In this study, expression of estrogen receptor α (ER α), progesterone receptor (PR), p53, and Ki67 were evaluated by immunohistochemistry in 12 sea lions with metastatic carcinoma, genital epithelial dysplasia, and intraepithelial neoplasia; 4 with genital epithelial dysplasia and intraepithelial neoplasia without metastases; and 6 control animals. Dysplastic and neoplastic lesions were identified in multiple areas of the cervix, vagina, penis, prepuce, and urethra in affected animals, suggesting multicentric development. Lesions were graded according to degree of epithelial dysplasia and infiltration and lesions of different grades were evaluated separately. Estrogen receptor expression was lower in intraepithelial lesions compared with normal genital epithelium, and expression in metastatic lesions was completely absent. There was progesterone receptor expression in neoplastic cells in intraepithelial lesions of all grades and in metastases, with no significant difference between lesion grades or between control and affected epithelium. Ki67 index and p53 expression increased with lesion grade and were higher in lesions than normal epithelium. Metastatic tumors exhibited highly variable morphology; however, proliferation index, ER α, PR, and p53 expression were similar in tumors with different patterns of growth. These results suggest that endogenous hormones, environmental contaminants that interact with steroid hormone receptors, and alterations in p53 may play a role in urogenital carcinogenesis in California sea lions.
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Affiliation(s)
- K. M. Colegrove
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis
| | | | - D. K. Naydan
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA
| | - L. J. Lowenstine
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis
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Abstract
A 10-yr-old male South American sea lion (Otaria byronia) died after several weeks of depression, anorexia, weight loss, and progressive respiratory distress. At necropsy, three confluent, lobulated, dark-red masses were noted in the mesentery. Similar masses were also observed in the lung and both kidneys. Hemangiosarcoma was diagnosed based on gross findings, histopathology, and immunohistochemistry. This is the first case of hemangiosarcoma reported in pinnipeds.
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