1
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Shah PT, Nawal Bahoussi A, Ahmad A, Sikandar M, Xing L. Bovine viral diarrhea virus in China: A comparative genomic and phylogenetic analysis with complete genome sequences. Front Vet Sci 2022; 9:992678. [PMID: 36118332 PMCID: PMC9478372 DOI: 10.3389/fvets.2022.992678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV), causing bovine viral diarrhea (BVD) in cattle, is one of the highly contagious and devastating diseases of cattle. Since 1980, BVDV has been identified all-over China in a variety of animal species including cattle, camels, yaks, sheep, water buffalo, goats, Sika deer and pigs. In this study, 31 BVDV complete genomes reported in China (from 2004 to 2020) with other 112 genomes reported around the world were comparatively analyzed. Phylogenetic analysis shows that BVDV genomes reported worldwide clustered in three major clades i.e., BVDV-1, BVDV-2, and BVDV-3. The BVDV-1 is genetically the most diverged genotype and phylogenetically classified into 7 sub-clades in our study based on full-length genomes. The China BVDV genomes fall into all three major clades, e.g., BVDV-1, BVDV-2 and BVDV-3. China BVDV-1 clustered into five sub-clades, e.g., 1, 2, 3, 6 and 7, where sub-clade 7 clustered as a separate sub-clade. Full-length genome recombination analysis reveals that the BVDV-1 reported in China appears to be mainly involved in recombination events. In addition, comparative analysis of E2 proteins between BVDV-1, BVDV-2, and BVDV-3 reveals that the amino acid variations could affect 12 potential linear B cell epitopes, demonstrating a dramatic antigen drift in the E2 protein. These results provide a thorough view of the information about the genetic and antigenic diversity of BVDVs circulating in China and therefore could benefit the development of suitable strategies for disease control.
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Affiliation(s)
- Pir Tariq Shah
- Institutes of Biomedical Sciences, Shanxi University, Taiyuan, China
| | | | - Aftab Ahmad
- School of Life Science, Shanxi University, Taiyuan, China
| | - Muhammad Sikandar
- Institutes of Biomedical Sciences, Shanxi University, Taiyuan, China
| | - Li Xing
- Institutes of Biomedical Sciences, Shanxi University, Taiyuan, China
- The Key Laboratory of Medical Molecular Cell Biology of Shanxi Province, Shanxi University, Taiyuan, China
- Shanxi Provincial Key Laboratory for Prevention and Treatment of Major Infectious Diseases, Taiyuan, China
- *Correspondence: Li Xing
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2
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Casas E, Falkenberg SM, Dassanayake RP, Register KB, Neill JD. MicroRNA profiles for different tissues from calves challenged with Mycoplasma bovis or challenged with Mycoplasma bovis and bovine viral diarrhea virus. PLoS One 2022; 17:e0271581. [PMID: 35862485 PMCID: PMC9302808 DOI: 10.1371/journal.pone.0271581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 07/03/2022] [Indexed: 11/18/2022] Open
Abstract
The objective was to determine differences in microRNAs (miRNAs) counts in several tissues of calves challenged with Mycoplasma bovis (M. bovis) or with M. bovis and bovine viral diarrhea virus (BVDV). Eight calves approximately 2 months of age were randomly assigned to three groups: Control (CT; n = 2), M. bovis (MB; n = 3), and Coinfection (CO; n = 3). On day 0, calves in CO were intranasally challenged with BVDV and calves in MB with M. bovis. On day 6, CO calves were challenged with M. bovis. Calves were euthanized 17 days post-challenge and serum (SER), white blood cells (WBC), liver (LIV), mesenteric (MLN) and tracheal-bronchial (TBLN) lymph nodes, spleen (SPL), and thymus (THY), were collected at necropsy. MiRNAs were extracted from each tissue from each calf. Significant (P< 0.01) differences in miRNAs expression were observed in SER, LIV, MLN, TBLN, SPL, and THY. There were no significant (P> 0.05) miRNAs in WBC. In SER, the CO group had levels of miR-1343-3p significantly higher than the CT and MB groups (P = 0.0071). In LIV and SPL, the CO group had the lowest counts for all significant miRNAs compared to CT and MB. In TBLN, the CT group had the highest counts of miRNAs, compared to MB and CO, in 14 of the 21 significant miRNAs. In THY, the CO group had the highest counts, in 4 of the 6 significant miRNAs compared to CT and MB. BVDV was associated with reduction of miRNAs in LIV, SPL, MLN, and TBLN, and M. bovis reduced counts of miRNAs in only TBLN. Measuring circulating miRNAs to assess disease condition or to develop intervention strategies to minimize respiratory diseases in cattle caused by BVDV or M. bovis will be of limited use unless an alternative approach is developed to use them as indicators of disease.
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Affiliation(s)
- Eduardo Casas
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, United States of America
- * E-mail:
| | - Shollie M. Falkenberg
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, United States of America
| | - Rohana P. Dassanayake
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, United States of America
| | - Karen B. Register
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, United States of America
| | - John D. Neill
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, United States of America
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3
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Congenital Cataracts and Microphakia with Retinal Dysplasia and Optic Nerve Hypoplasia in a Calf. Case Rep Vet Med 2021; 2021:2064103. [PMID: 34532149 PMCID: PMC8440096 DOI: 10.1155/2021/2064103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/12/2021] [Accepted: 07/09/2021] [Indexed: 11/18/2022] Open
Abstract
Case Description. A two-month-old, female, Aberdeen-Angus calf was presented for congenital cataracts and blindness in both eyes (OU). The dam had a reported history of visual defects (not specified) and had produced other affected calves (per owner history). Ophthalmic examination revealed mature bilateral cataracts, attenuation of the iridic granules, persistent pupillary membranes, and dyscoric pupils. Additionally, the calf had a poor body condition, prognathism, dome-shaped head, excessive nasal drainage, limb contracture, and fever. Histopathology of both eyes revealed lenticular degeneration (congenital cataracts), retinal dysplasia, and optic nerve hypoplasia. BVDV IHC detected antigen within only the left eye (OS), consisting of intrahistiocytic and endothelial immunoreactivity within the ciliary body, iris, and choroid. No BVDV immunoreactivity could be detected in the right eye (OD). This case highlights the unique ocular changes present in in utero BVDV infection of cattle with a different immunohistochemical staining profile than previously described.
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4
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Bauermann FV, Ridpath JF. Epidemiology of Pestivirus H in Brazil and Its Control Implications. Front Vet Sci 2021; 8:693041. [PMID: 34368280 PMCID: PMC8342886 DOI: 10.3389/fvets.2021.693041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/11/2021] [Indexed: 11/21/2022] Open
Abstract
Along with viruses in the Pestivirus A (Bovine Viral Diarrhea Virus 1, BVDV1) and B species (Bovine Viral Diarrhea Virus 2, BVDV2), members of the Pestivirus H are mainly cattle pathogens. Viruses belonging to the Pestivirus H group are known as HoBi-like pestiviruses (HoBiPev). Genetic and antigenic characterization suggest that HoBiPev are the most divergent pestiviruses identified in cattle to date. The phylogenetic analysis of HoBiPev results in at least five subgroups (a–e). Under natural or experimental conditions, calves infected with HoBiPev strains typically display mild upper respiratory signs, including nasal discharge and cough. Although BVDV1 and BVDV2 are widely distributed and reported in many South American countries, reports of HoBiPev in South America are mostly restricted to Brazil. Despite the endemicity and high prevalence of HoBiPev in Brazil, only HoBiPev-a was identified to date in Brazil. Unquestionably, HoBiPev strains in BVDV vaccine formulations are required to help curb HoBiPev spread in endemic regions. The current situation in Brazil, where at this point only HoBiPev-a seems present, provides a more significant opportunity to control these viruses with the use of a vaccine with a single HoBiPev subtype. Despite the lack of differentiation among bovine pestiviruses by current BVDV tests, the reduced genetic variability of HoBiPev in Brazil may allow reliable identification of cases within the region. On the other hand, introducing foreign ruminants, biologicals, and genetic material to South America, especially if it originated from other HoBiPev-endemic countries, should consider the risk of introducing divergent HoBiPev subtypes.
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Affiliation(s)
- Fernando V Bauermann
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University (OSU), Stillwater, OK, United States
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5
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Oliveira TES, Scuisato GS, Pelaquim IF, Cunha CW, Cunha LS, Flores EF, Pretto-Giordano LG, Lisbôa JAN, Alfieri AA, Saut JPE, Jorge da Cunha PH, Headley SA. The Participation of a Malignant Catarrhal Fever Virus and Mycoplasma bovis in the Development of Single and Mixed Infections in Beef and Dairy Cattle With Bovine Respiratory Disease. Front Vet Sci 2021; 8:691448. [PMID: 34368279 PMCID: PMC8339727 DOI: 10.3389/fvets.2021.691448] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/20/2021] [Indexed: 11/16/2022] Open
Abstract
The bovine respiratory disease (BRD) complex is a multietiological and multifactorial disease associated with a wide range of viral and bacterial pathogens. This study evaluated the contribution of specific infectious disease agents in the development of BRD in cattle from Brazil and determined if a virus within the malignant catarrhal fever virus (MCFV) group and Mycoplasma bovis, acting individually or in conjunction, can be associated with the development of BRD. Formalin-fixed paraffin-embedded pulmonary sections were used in immunohistochemical assays to determine the intralesional presence of six antigens associated with BRD: bovine alphaherpesvirus 1 (BoHV-1), bovine parainfluenza virus 3 (BPIV-3), bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), MCFV, and M. bovis. Pneumonia was diagnosed in 82.7% (120/145) of all cattle evaluated. Interstitial pneumonia (60%, 72/120) and suppurative bronchopneumonia (25.8%, 31/120) were the most frequent patterns of pneumonia identified. Intralesional antigens of MCFV (53.3%, 64/120) were the most frequently associated with BRD, followed by M. bovis (47.5%, 57/120), BVDV (42.5%, 51/120), BoHV-1 (28.3%, 34/120), BRSV (24.2%, 29/120), and BPIV-3 (8.3%, 10/120). Additionally, antigens of BVDV, MCFV, and M. bovis were the most frequently identified agents associated with singular and concomitant infections. The MCFV identified during this study is more likely to be ovine gammaherpesvirus 2 (OvHV-2), since OvHV-2 is the only MCFV identified within the geographical region of this study. Interstitial pneumonia with proliferative vascular lesions may be a useful histologic feature to differentiate MCFV-induced pneumonia from other viral pneumonias of cattle. These results demonstrate that MCFV and M. bovis, in single or mixed infections, can produce pneumonia in cattle and should therefore be considered as primary agents in the development of BRD.
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Affiliation(s)
- Thalita Evani Silva Oliveira
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Brazil.,National Institutes of Science and Technology, Dairy Production Chain (INCT-Leite), Universidade Estadual de Londrina, Londrina, Brazil
| | - Gabriela Sanches Scuisato
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Brazil
| | - Isadora Fernanda Pelaquim
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Brazil
| | - Cristina Wetzel Cunha
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, United States.,Department of Veterinary Microbiology and Pathology and Paul G. Alan School for Global Animal Health, Washington State University, Pullman, WA, United States
| | - Lucas Santana Cunha
- Department of Statistics, Universidade Estadual de Londrina, Londrina, Brazil
| | - Eduardo Furtado Flores
- Department of Preventive Veterinary Medicine, Universidade Federal de Santa Maria, Santa Maria, Brazil
| | - Lucienne Garcia Pretto-Giordano
- Laboratory of Veterinary Microbiology and Infectious Diseases, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, Brazil
| | - Júlio Augusto Naylor Lisbôa
- National Institutes of Science and Technology, Dairy Production Chain (INCT-Leite), Universidade Estadual de Londrina, Londrina, Brazil.,Large Animal Internal Medicine, Department of Veterinary Clinics, Universidade Estadual de Londrina, Londrina, Brazil
| | - Amauri Alcindo Alfieri
- National Institutes of Science and Technology, Dairy Production Chain (INCT-Leite), Universidade Estadual de Londrina, Londrina, Brazil.,Laboratory of Animal Virology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina, Londrina, Brazil
| | - João Paulo Elsen Saut
- Large Animal Health Laboratory, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | | | - Selwyn Arlington Headley
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Brazil.,National Institutes of Science and Technology, Dairy Production Chain (INCT-Leite), Universidade Estadual de Londrina, Londrina, Brazil.,Programa de Pós-Graduação em Biociência Animal, Universidade de Cuiabá, Cuiabá, Brazil
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6
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Wang K, Thomas C, Zhang S, Wathes DC, Cheng Z. Comparison of the Ability of High and Low Virulence Strains of Non-cytopathic Bovine Viral Diarrhea Virus-1 to Modulate Expression of Interferon Tau Stimulated Genes in Bovine Endometrium. Front Vet Sci 2021; 8:659330. [PMID: 33898551 PMCID: PMC8062762 DOI: 10.3389/fvets.2021.659330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/15/2021] [Indexed: 12/20/2022] Open
Abstract
Bovine Viral Diarrhea virus (BVDV) is a pestivirus with a single-stranded, positive sense RNA genome. It is endemic in many cattle populations, causing major economic losses in part due to reduced fertility. BVDV exhibits great genetic diversity and is classified as type 1 or 2 (BVDV-1, BVDV-2) with either non-cytopathogenic (ncp) or cytopathogenic (cp) biotypes. Differing strains of ncpBVDV differ in virulence, affecting clinical outcome. BVDV replicates in the reproductive tract, affecting host immunity and embryo survival. This study used an in vitro model of primary bovine endometrial cell cultures to compare the effects of two BVDV ncp type 1a strains of differing virulence (termed HO and KY) on endometrial transcription of candidate interferon stimulated genes (ISG) using qPCR. Half the cultures were stimulated with interferon tau (IFNT, the conceptus produced pregnancy recognition factor) in the presence or absence of viral infection. Cultures were replicated on cells from 10 BVDV-free cows. IFNT treatment stimulated transcription of 10 candidate ISGs, whereas both ncpBVDV-1 strains alone inhibited transcription of 8/10 ISGs. In combined BVDV-1+IFNT cultures, the stimulatory effect of IFNT on expression of GBP4, ISG15, HERC5, RSAD2, IFIH1, IFIT3, and MX1 was significantly inhibited by HO, but only ISG15, RSAD2, IFI27, and IFIT3 were decreased by KY. Inhibition by HO was generally greater. The IFNT-induced expression of TRIM56 was, however, increased by HO. These data show that HO, the more virulent ncpBVDV-1 strain, has a greater capacity to inhibit key antiviral pathways. These differences need confirmation at the protein level but may influence immune tolerance of the host. They could also reduce fertility by increasing uterine susceptibility to bacterial infection and disrupting IFNT-mediated pregnancy recognition.
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Affiliation(s)
- Kai Wang
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom.,Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, China
| | - Carole Thomas
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | - Shujun Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, China
| | - D Claire Wathes
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | - Zhangrui Cheng
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
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7
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Falkenberg SM, Dassanayake RP, Palmer MV, Silveira S, Roth JA, Gauger E, Kaiser TJ, Guidarini C, Neill JD, Ridpath JF. Changes in circulating lymphocytes and lymphoid tissue associated with vaccination of colostrum deprived calves. Vaccine 2020; 38:7268-7277. [PMID: 32988689 DOI: 10.1016/j.vaccine.2020.09.046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/03/2020] [Accepted: 09/15/2020] [Indexed: 10/23/2022]
Abstract
The objective of this study was to compare immunological responses and lymphoid depletion in young, colostrum deprived calves following administration of vaccines containing modified-live bovine viral diarrhea virus (BVDV). A group of calves exposed to a typical virulence non-cytopathic (ncp) BVDV-2 field strain (ncp exposed) was included to compare responses of calves receiving vaccine to responses generated against a field strain (mimicking a natural infection). A negative control group administered a placebo was used in all comparisons. All vaccines used in the study were administered per manufacturer recommendations while ncp BVDV exposed calves received 5 ml intranasally (2.5 ml/nare; 4.2 × 106 TCID50/ml) of the BVDV-2 field strain. Samples collected at each time point included nasal swabs for virus detection, blood samples for complete blood counts and detection of viremia, PBMCs for flow cytometric analysis, serum for virus neutralization titers, and thymus tissue at necropsy for evaluation of lymphoid depletion. A measurable neutralizing BVDV titer was observed for all treatment groups excluding the control animals, which remained negative during the study period. Virus shedding was only detected from the ncp vaccinated and ncp exposed calves. A decline from baseline was observed for peripheral lymphocyte and CD4+ cells for the groups receiving the adjuvanted cytopathic (cp) vaccine, the double deleted genetically modified (ddGM) vaccine, the ncp vaccine and ncp exposed calves, but not for the control group or groups receiving cp vaccines. Thymus depletion was observed for the ncp vaccine and ncp exposed calves and to a lesser extent for the ddGM vaccine calves. Collectively, these data suggest that the virus biotype, method of attenuation, presentation, and use of adjuvant will influence vaccine impacts on lymphoid tissues and the immune response. As such, multiple variables should be considered when determining costs and benefits of vaccination.
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Affiliation(s)
- Shollie M Falkenberg
- USDA, Agricultural Research Service, National Animal Disease Center, Ruminant Diseases and Immunology Research Unit, Ames, IA 50010, USA.
| | - Rohana P Dassanayake
- USDA, Agricultural Research Service, National Animal Disease Center, Ruminant Diseases and Immunology Research Unit, Ames, IA 50010, USA
| | - Mitchell V Palmer
- USDA, Agricultural Research Service, National Animal Disease Center, Bacterial Diseases of Livestock Research Unit, Ames, IA 50010, USA
| | - Simone Silveira
- Laboratório de Virologia, Faculdade de Medicina Veterinária, Universidade do Oeste de Santa Catarina (UNOESC), Xanxerê, SC, Brazil
| | - James A Roth
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Eric Gauger
- Boehringer Ingelheim Animal Health, Ames, IA, USA
| | - Troy J Kaiser
- Boehringer Ingelheim Animal Health, St. Joseph, MO, USA
| | | | - John D Neill
- USDA, Agricultural Research Service, National Animal Disease Center, Ruminant Diseases and Immunology Research Unit, Ames, IA 50010, USA
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8
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Mechanisms linking bovine viral diarrhea virus (BVDV) infection with infertility in cattle. Anim Health Res Rev 2019; 20:72-85. [PMID: 31895016 DOI: 10.1017/s1466252319000057] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Bovine viral diarrhea virus (BVDV) is an important infectious disease agent that causes significant reproductive and economic losses in the cattle industry worldwide. Although BVDV infection is known to cause poor fertility in cattle, a greater part of the underlying mechanisms particularly associated with early reproductive losses are not clearly understood. Previous studies reported viral compromise of reproductive function in infected bulls. In females, BVDV infection is thought to be capable of killing the oocyte, embryo or fetus directly, or to induce lesions that result in fetal abortion or malformation. BVDV infections may also induce immune dysfunction, and predispose cattle to other diseases that cause poor health and fertility. Other reports also suggested BVDV-induced disruption of the reproductive endocrine system, and a disruption of leukocyte and cytokine functions in the reproductive organs. More recent studies have provided evidence of viral-induced suppression of endometrial innate immunity that may predispose to uterine disease. Furthermore, there is new evidence that BVDV may potentially disrupt the maternal recognition of pregnancy or the immune protection of the conceptus. This review brings together the previous reports with the more recent findings, and attempts to explain some of the mechanisms linking this important virus to infertility in cattle.
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9
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Silveira S, Falkenberg SM, Dassanayake RP, Walz PH, Ridpath JF, Canal CW, Neill JD. In vitro method to evaluate virus competition between BVDV-1 and BVDV-2 strains using the PrimeFlow RNA assay. Virology 2019; 536:101-109. [PMID: 31415943 DOI: 10.1016/j.virol.2019.07.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/26/2019] [Accepted: 07/31/2019] [Indexed: 12/29/2022]
Abstract
Bovine viral diarrhea viruses (BVDV), segregated in BVDV-1 and BVDV-2 species, lead to substantial economic losses to the cattle industry worldwide. It has been hypothesized that there could be differences in level of replication, pathogenesis and tissue tropism between BVDV-1 and BVDV-2 strains. Thus, this study developed an in vitro method to evaluate virus competition between BVDV-1 and BVDV-2 strains. To this end the competitive dynamics of BVDV-1a, BVDV-1b, and BVDV-2a strains in cell cultures was evaluated by a PrimeFlow RNA assay. Similar results were observed in this study, as was observed in an earlier in vivo transmission study. Competitive exclusion was observed as the BVDV-2a strains dominated and excluded the BVDV-1a and BVDV-1b strains. The in vitro model developed can be used to identify viral variations that result in differences in frequency of subgenotypes detected in the field, vaccine failure, pathogenesis, and strain dependent variation in immune responses.
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Affiliation(s)
- S Silveira
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil
| | - S M Falkenberg
- Ruminant Diseases and Immunology Unit, National Animal Disease Center/ARS/USDA, Ames, IA, USA.
| | - R P Dassanayake
- Ruminant Diseases and Immunology Unit, National Animal Disease Center/ARS/USDA, Ames, IA, USA
| | - P H Walz
- Department of Pathobiology, College of Veterinary Medicine, 129 Sugg Laboratory, Auburn University, AL, 36849, USA
| | - J F Ridpath
- Ruminant Diseases and Immunology Unit, National Animal Disease Center/ARS/USDA, Ames, IA, USA
| | - C W Canal
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil
| | - J D Neill
- Ruminant Diseases and Immunology Unit, National Animal Disease Center/ARS/USDA, Ames, IA, USA
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10
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Neill JD, Workman AM, Hesse R, Bai J, Porter EP, Meadors B, Anderson J, Bayles DO, Falkenberg SM. Identification of BVDV2b and 2c subgenotypes in the United States: Genetic and antigenic characterization. Virology 2018; 528:19-29. [PMID: 30553108 DOI: 10.1016/j.virol.2018.12.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/03/2018] [Accepted: 12/03/2018] [Indexed: 01/22/2023]
Abstract
Bovine viral diarrhea virus (BVDV), a ubiquitous pathogen of cattle, causes subclinical to severe acute disease. Two species of BVDV are recognized, BVDV1 and BVDV2 with BVDV1 divided into at least 21 subgenotypes and BVDV2 into 3-4 subgenotypes, most commonly using sequences from the 5' untranslated region (5' UTR). We report genomic sequencing of 8 BVDV2 isolates that did not segregate into the 2a subgenotype; but represented two additional BVDV2 subgenotypes. One BVDV2 subgenotype was previously recognized only in Asia. The other seven viruses fell into a second subgenotype that was first reported in Brazil and the U.S. in 2002. Neutralization assays using antiserum raised against vaccine strain BVDV2a 296c revealed varying degrees of neutralization of genetically diverse BVDV2 isolates. Neutralization titers decreased from 1.8 to more than a four log(2) decrease. This study illustrated the considerable genetic and antigenic diversity in BVDV2 circulating in the U.S.
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Affiliation(s)
- John D Neill
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, USDA, ARS, Ames, IA 50010, USA.
| | - Aspen M Workman
- US Meat Animal Research Center, USDA, ARS, Clay Center, NE 68933, USA
| | - Richard Hesse
- Kansas State Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, KS, 66502 USA
| | - Jianfa Bai
- Kansas State Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, KS, 66502 USA
| | - Elizabeth Poulsen Porter
- Kansas State Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, KS, 66502 USA
| | - Barbara Meadors
- Kansas State Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, KS, 66502 USA
| | - Joe Anderson
- Kansas State Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, KS, 66502 USA
| | - Darrell O Bayles
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, USDA, ARS, Ames, IA 50010, USA
| | - Shollie M Falkenberg
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, USDA, ARS, Ames, IA 50010, USA
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11
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Induction of functional interferon alpha and gamma responses during acute infection of cattle with non-cytopathic bovine viral diarrhea virus. Vet Microbiol 2016; 195:104-114. [PMID: 27771055 DOI: 10.1016/j.vetmic.2016.09.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 09/19/2016] [Accepted: 09/20/2016] [Indexed: 01/12/2023]
Abstract
As a part of their pathogenic mechanism, many pathogens causing persistent infections, including bovine viral diarrhea virus (BVDV), immunosuppress their hosts, often by limiting the ability to either produce, or respond to, interferon. The objective of this study was to quantify the extent to which an acute infection of cattle with a non-cytopathic strain of BVDV induces interferon responses and to establish the functionality of these responses. Functionality of responses was investigated using a bovine specific peptide array to monitor kinase-mediated signal transduction activity within peripheral blood mononuclear cells (PBMCs) at time points corresponding to the interferon gamma (IFN-γ) and alpha (IFN-α) responsive phases of acute BVDV infection. Further, with an appreciation of diverse mechanisms and levels at which pathogens modulate host cell defences, patterns of expression of IFN-γ and -α responsive genes were also quantified within PBMCs. Infection of cows with ncpBVDV2-1373 induced significant increases in levels of serum IFN-γ and IFN-α. Within the PBMCs of the infected animals, distinct patterns of kinase-mediated signal transduction activity, in particular with respect to activation of classic IFN-activated signalling pathways, such as Jak-Stat, as well as induced expression of IFN-γ and IFN-α regulated genes, support the functionality of the host interferon response.
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Downey-Slinker E, Ridpath J, Sawyer J, Skow L, Herring A. Antibody titers to vaccination are not predictive of level of protection against a BVDV type 1b challenge in Bos indicus - Bos taurus steers. Vaccine 2016; 34:5053-5059. [DOI: 10.1016/j.vaccine.2016.08.087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 01/08/2023]
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13
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Schaut RG, Ridpath JF, Sacco RE. Bovine Viral Diarrhea Virus Type 2 Impairs Macrophage Responsiveness to Toll-Like Receptor Ligation with the Exception of Toll-Like Receptor 7. PLoS One 2016; 11:e0159491. [PMID: 27420479 PMCID: PMC4946783 DOI: 10.1371/journal.pone.0159491] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 07/05/2016] [Indexed: 12/20/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV) is a member of the Flaviviridae family. BVDV isolates are classified into two biotypes based on the development of cytopathic (cp) or non-cytopathic (ncp) effects in epithelial cell culture. BVDV isolates are further separated into species, BVDV1 and 2, based on genetic differences. Symptoms of BVDV infection range from subclinical to severe, depending on strain virulence, and may involve multiple organ systems and induction of a generalized immunosuppression. During BVDV-induced immune suppression, macrophages, critical to innate immunity, may have altered pathogen recognition receptor (PRR) signaling, including signaling through toll-like receptors (TLRs). Comparison of BVDV 2 strains with different biotypes and virulence levels is valuable to determining if there are differences in host macrophage cellular responses between viral phenotypes. The current study demonstrates that cytopathic (cp), noncytopathic (ncp), high (hv) or low virulence (lv) BVDV2 infection of bovine monocyte-derived macrophages (MDMΦ) result in differential expression of pro-inflammatory cytokines compared to uninfected MDMΦ. A hallmark of cp BVDV2 infection is IL-6 production. In response to TLR2 or 4 ligation, as might be observed during secondary bacterial infection, cytokine secretion was markedly decreased in BVDV2-infected MDMΦ, compared to non-infected MDMΦ. Macrophages were hyporesponsive to viral TLR3 or TLR8 ligation. However, TLR7 stimulation of BVDV2-infected MDMΦ induced cytokine secretion, unlike results observed for other TLRs. Together, these data suggest that BVDV2 infection modulated mRNA responses and induced a suppression of proinflammatory cytokine protein responses to TLR ligation in MDMΦ with the exception of TLR7 ligation. It is likely that there are distinct differences in TLR pathways modulated following BVDV2 infection, which have implications for macrophage responses to secondary infections.
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Affiliation(s)
- Robert G. Schaut
- Immunobiology Graduate Program, Iowa State University, Ames, Iowa, United States of America
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, Ames, Iowa, United States of America
| | - Julia F. Ridpath
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, Ames, Iowa, United States of America
| | - Randy E. Sacco
- Immunobiology Graduate Program, Iowa State University, Ames, Iowa, United States of America
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, Ames, Iowa, United States of America
- * E-mail:
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Experimental infection with non-cytopathic bovine viral diarrhea virus 1 in mice induces inflammatory cell infiltration in the spleen. Arch Virol 2016; 161:2527-35. [PMID: 27376375 DOI: 10.1007/s00705-016-2952-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 06/24/2016] [Indexed: 10/21/2022]
Abstract
Previously, our study showed that oral inoculation of mice with cytopathic (cp) bovine viral diarrhea virus (BVDV) led to lymphocyte depletion and increased numbers of megakaryocytes in the spleen as well as thrombocytopenia and lymphopenia. In the present study, to investigate the possible differences in the detection of viral antigen, histopathological lesions, and hematologic changes between non-cytopathic (ncp) BVDV1 and cp BVDV1, mice were orally administered low and high doses of ncp BVDV1 and were necropsied at days 0, 2, 5, and 9 postinfection (pi). None of the ncp BVDV1-infected mice exhibited clinical signs of illness, unlike those infected with cp BVDV1. Statistically significant thrombocytopenia was observed during ncp BVDV1 infection, and lymphopenia was found only in mice infected with a high dose at day 9 pi. Interestingly, ncp BVDV1 infection increased the numbers of basophils, eosinophils, neutrophils, and monocytes in some infected mice. Viral antigen was detected in the lymphocytes of the spleen, mesenteric lymph nodes, Peyer's patches, and bone marrow by immunohistochemistry. Lymphoid depletion was evident in the mesenteric lymph nodes of mice infected with a high dose and also found in the Peyer's patches of some infected mice. Infiltration of inflammatory cells, including neutrophils and monocytes, and an increased number of megakaryocytes were seen in the spleen. These results suggest that the distribution of viral antigens is not associated with the presence of histopathological lesions. Inflammatory cell infiltration was observed in the spleens as a result of viral replication and may be attributable to the host reaction to ncp BVDV1 infection. Together, these findings support the possibility that mice can be used as an animal model for BVDV infection.
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Noncytopathic bovine viral diarrhea virus 2 impairs virus control in a mouse model. Arch Virol 2015; 161:395-403. [PMID: 26586332 DOI: 10.1007/s00705-015-2665-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 10/28/2015] [Indexed: 12/25/2022]
Abstract
Bovine viral diarrhea virus (BVDV) is an economically important pathogen that causes development of mild to severe clinical signs in wild and domesticated ruminants. We previously showed that mice could be infected by BVDV. In the present study, we infected mice intraperitoneally with non-cytopathic (ncp) BVDV1 or ncp BVDV2, harvested the blood and organs of the infected mice at days 4, 7, 10 and 14 postinfection (pi), and performed immunohistochemical analyses to confirm BVDV infection. Viral antigens were detected in the spleens of all infected mice from days 4 through 14 and were also found in the mesenteric lymph nodes, gut-associated lymphoid tissue (GALT), heart, kidney, intestine, and bronchus-associated lymphoid tissue (BALT) of some infected mice. In ncp BVDV2-infected mice, flow cytometric analysis revealed markedly fewer CD4(+) and CD8(+) T lymphocytes and lower expression of costimulatory molecules CD80 (B7-1) and CD86 (B7-2) and major histocompatibility complex (MHC) class II (I-A/I-E) than those in ncp BVDV1-infected mice. Production of the cytokines interleukin (IL)-6 and monocyte chemotactic protein (MCP)-1 was higher in the plasma of ncp BVDV2-infected mice than that in that of ncp BVDV1-infected mice. Our results demonstrate that ncp BVDV1 and ncp BVDV2 interact differently with the host innate immune response in vivo. These findings highlight an important distinction between ncp BVDV1 and ncp BVDV2 and suggest that ncp BVDV2 impairs the host's ability to control the infection and enhances virus dissemination.
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Palomares RA, Sakamoto K, Walz HL, Brock KV, Hurley DJ. Acute infection with bovine viral diarrhea virus of low or high virulence leads to depletion and redistribution of WC1(+) γδ T cells in lymphoid tissues of beef calves. Vet Immunol Immunopathol 2015; 167:190-5. [PMID: 26282369 DOI: 10.1016/j.vetimm.2015.07.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/05/2015] [Accepted: 07/30/2015] [Indexed: 11/16/2022]
Abstract
The objective of this study was to determine the abundance and distribution of γδ T lymphocytes in lymphoid tissue during acute infection with high (HV) or low virulence (LV) non-cytopathic bovine viral diarrhea virus (BVDV) in beef calves. This study was performed using tissue samples from a previous experiment in which thirty beef calves were randomly assigned to 1 of 3 groups: LV [n=10; animals inoculated intranasally (IN) with LV BVDV-1a (strain SD-1)], HV [n=10; animals inoculated IN with HV BVDV-2 (strain 1373)], and control (n=10; animals inoculated with cell culture medium). On day 5 post inoculation, animals were euthanized, and samples from spleen and mesenteric lymph nodes (MLN) were collected to assess the abundance of WC1(+) γδ T cells. A higher proportion of calves challenged with BVDV showed signs of apoptosis and cytophagy in MLN and spleen samples compared to the control group. A significantly lower number of γδ T cells was observed in spleen and MLN from calves in HV and LV groups than in the control calves (P<0.05). In conclusion, acute infection with HV or LV BVDV resulted in depletion of WC1(+) γδ T cells in mucosal and systemic lymphoid tissues at five days after challenge in beef calves. This reduction in γδ T cells in the studied lymphoid tissues could be also due to lymphocyte trafficking to other tissues.
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Affiliation(s)
- Roberto A Palomares
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602-2771, United States.
| | - Kaori Sakamoto
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602-2771, United States
| | - Heather L Walz
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, United States
| | - Kenny V Brock
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, United States
| | - David J Hurley
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602-2771, United States
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Schaut RG, McGill JL, Neill JD, Ridpath JF, Sacco RE. Bovine viral diarrhea virus type 2 in vivo infection modulates TLR4 responsiveness in differentiated myeloid cells which is associated with decreased MyD88 expression. Virus Res 2015; 208:44-55. [PMID: 26043978 DOI: 10.1016/j.virusres.2015.05.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 05/18/2015] [Accepted: 05/22/2015] [Indexed: 02/06/2023]
Abstract
Symptoms of bovine viral diarrhea virus (BVDV) infection range from subclinical to severe, depending on strain virulence. Several in vitro studies showed BVDV infection impaired leukocyte function. Fewer studies have examined the effects of in vivo BVDV infection on monocyte/macrophage function, especially with strains of differing virulence. We characterized cytokine production by bovine myeloid cells isolated early or late in high (HV) or low virulence (LV) BVDV2 infection. Given BVDV infection may enhance susceptibility to secondary bacterial infection, LPS responses were examined as well. Monocytes from HV and LV infected calves produced higher levels of cytokines compared to cells from controls. In contrast, monocyte-derived macrophage cytokine levels were generally reduced. Modulated cytokine expression in HV BVDV2 macrophages was associated with decreased MyD88 expression, likely due to its interaction with viral NS5A. These data and those of others, suggest that certain Flaviviridae may have evolved strategies for subverting receptor signaling pathways involving MyD88.
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Affiliation(s)
- Robert G Schaut
- Immunobiology Interdepartmental Graduate Program, Iowa State University, 2018 Molecular Biology Building, Ames, IA 50011, USA; Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, 1920 Dayton Avenue, Ames, IA 50010, USA
| | - Jodi L McGill
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, 1920 Dayton Avenue, Ames, IA 50010, USA
| | - John D Neill
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, 1920 Dayton Avenue, Ames, IA 50010, USA
| | - Julia F Ridpath
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, 1920 Dayton Avenue, Ames, IA 50010, USA
| | - Randy E Sacco
- Immunobiology Interdepartmental Graduate Program, Iowa State University, 2018 Molecular Biology Building, Ames, IA 50011, USA; Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS, USDA, 1920 Dayton Avenue, Ames, IA 50010, USA.
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18
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Abstract
Pestiviruses are among the economically most important pathogens of livestock. The biology of these viruses is characterized by unique and interesting features that are both crucial for their success as pathogens and challenging from a scientific point of view. Elucidation of these features at the molecular level has made striking progress during recent years. The analyses revealed that major aspects of pestivirus biology show significant similarity to the biology of human hepatitis C virus (HCV). The detailed molecular analyses conducted for pestiviruses and HCV supported and complemented each other during the last three decades resulting in elucidation of the functions of viral proteins and RNA elements in replication and virus-host interaction. For pestiviruses, the analyses also helped to shed light on the molecular basis of persistent infection, a special strategy these viruses have evolved to be maintained within their host population. The results of these investigations are summarized in this chapter.
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Affiliation(s)
- Norbert Tautz
- Institute for Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Birke Andrea Tews
- Institut für Immunologie, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Gregor Meyers
- Institut für Immunologie, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.
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Romero-Palomo F, Risalde MA, Molina V, Lauzi S, Bautista MJ, Gómez-Villamandos JC. Characterization of thymus atrophy in calves with subclinical BVD challenged with BHV-1. Vet Microbiol 2015; 177:32-42. [PMID: 25759294 DOI: 10.1016/j.vetmic.2015.02.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 02/09/2015] [Accepted: 02/18/2015] [Indexed: 12/21/2022]
Abstract
Since the thymus is a target organ for the bovine viral diarrhea virus (BVDV), our experiment aimed to understand its relationship with the immunosuppressive effect by studying the consequences of a previous infection with BVDV on the thymus of calves challenged with bovine herpesvirus 1.1 (BHV-1). For this purpose, 12 animals were inoculated intranasally with non-cytopathic BVDV-1; 12 days later, 10 of them were coinfected intranasally with BHV-1. These animals were euthanized in batches of two at 0, 1, 2, 4, 7 or 14 dpi with BHV-1. Another 10 calves were inoculated solely with BHV-1 and euthanized in batches of two at 1, 2, 4, 7 or 14 dpi with BHV-1; two uninoculated calves were used as negative controls. Thymus samples from these animals were processed for viral detection and histopathological, immunohistochemical, and ultrastructural studies focused on BVDV/BHV-1 antigens, cortex:medulla ratio, apoptosis (TUNEL and caspase-3), collagen deposition, and factor VIII endothelial detection. Our study revealed the immunohistochemical presence of BVDV antigen in all animals in the BVDV-infected group, unlike BHV-1 detection, which was observed in animals in both infection groups only by molecular techniques. BVDV-preinfected animals showed severe atrophic changes associated with reduced cortex:medulla ratio, higher presence of cortical apoptosis, and increased collagen deposition and vascularization. However, calves solely infected with BHV-1 did not show atrophic changes. These findings could affect not only the numbers of circulating and local mature T cells but also the T cell-mediated immunity, which seems to be impaired during infections with this virus, thus favoring pathogenic effects during secondary infections.
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Affiliation(s)
- F Romero-Palomo
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Agrifood Campus of International Excellence (ceiA3), 14014 Córdoba, Spain
| | - M A Risalde
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Agrifood Campus of International Excellence (ceiA3), 14014 Córdoba, Spain
| | - V Molina
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Agrifood Campus of International Excellence (ceiA3), 14014 Córdoba, Spain
| | - S Lauzi
- Department of Veterinary Science and Public Health, University of Milan, 20133 Milan, Italy
| | - M J Bautista
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Agrifood Campus of International Excellence (ceiA3), 14014 Córdoba, Spain
| | - J C Gómez-Villamandos
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Agrifood Campus of International Excellence (ceiA3), 14014 Córdoba, Spain.
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20
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Palomares RA, Hurley DJ, Woolums AR, Parrish JE, Brock KV. Analysis of mRNA expression for genes associated with regulatory T lymphocytes (CD25, FoxP3, CTLA4, and IDO) after experimental infection with bovine viral diarrhea virus of low or high virulence in beef calves. Comp Immunol Microbiol Infect Dis 2014; 37:331-8. [PMID: 25456194 PMCID: PMC7112516 DOI: 10.1016/j.cimid.2014.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 09/26/2014] [Accepted: 10/03/2014] [Indexed: 12/13/2022]
Abstract
Immunosuppression caused by bovine viral diarrhea virus (BVDV) has been associated with lymphocyte depletion, leukopenia and impairment of leukocyte function; however, no work has been done on the relationship between BVDV and regulatory T lymphocytes (Tregs). The objective of this study was to compare the mRNA expression of genes associated with Tregs (CD25, FoxP3, CTLA4, and IDO), after experimental infection of beef calves with low (LV) or high (HV) virulence BVDV. Thirty BVDV-naïve calves were randomly assigned to three groups. Calves were intra-nasally inoculated with LV (n=10, strain SD-1) or HV (n=10, strain 1373) BVDV or BVDV-free cell culture medium (control, n=10). Quantitative RT-PCR was used to determine the expression of target genes in tracheo-bronchial lymph nodes and spleen on day 5 post-infection. The mRNA expression of CD25 was up-regulated in tracheo-bronchial lymph nodes of LV (P<0.05), but not in HV compared to the control group. The expression of FoxP3 and CTLA4 was not increased in tracheo-bronchial lymph nodes of either of the BVDV-inoculated groups. A dramatic up-regulation of IDO mRNA was observed in tracheo-bronchial lymph nodes of LV (P<0.05), but not HV compared to the control calves. In conclusion, experimental infection with BVDV did not provide evidence of Treg activation based on expression of FoxP3 and CTL4. Differential expression of CD25 and IDO mRNA on day 5 post-infection with HV or LV BVDV might reflect temporal differences in transcription occurring during the immune response elicited by these viral strains, or differences in viral infectivity of the host cells.
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Affiliation(s)
- Roberto A Palomares
- Department of Population Health, College of Veterinary Medicine, The University of Georgia, Athens, GA, United States.
| | - David J Hurley
- Department of Population Health, College of Veterinary Medicine, The University of Georgia, Athens, GA, United States
| | - Amelia R Woolums
- Department of Large Animal Medicine, College of Veterinary Medicine, The University of Georgia, Athens, GA, United States
| | - Jacqueline E Parrish
- Department of Population Health, College of Veterinary Medicine, The University of Georgia, Athens, GA, United States
| | - Kenny V Brock
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
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Expression of toll-like receptors and co-stimulatory molecules in lymphoid tissue during experimental infection of beef calves with bovine viral diarrhea virus of low and high virulence. Vet Res Commun 2014; 38:329-35. [DOI: 10.1007/s11259-014-9613-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 08/05/2014] [Indexed: 10/24/2022]
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22
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Changes observed in the thymus and lymph nodes 14 days after exposure to BVDV field strains of enhanced or typical virulence in neonatal calves. Vet Immunol Immunopathol 2014; 160:70-80. [PMID: 24809640 DOI: 10.1016/j.vetimm.2014.03.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 03/11/2014] [Accepted: 03/29/2014] [Indexed: 11/23/2022]
Abstract
Clinical presentation following uncomplicated acute infection with bovine viral diarrhea viruses (BVDV) ranges from clinically unapparent to severe (including hemorrhagic disease and death) depending on the strain virulence. Regardless of clinical presentation, BVDV infection of cattle results in a generalized immunosuppression. BVDV immunosuppression is characterized by a reduction of circulating white blood cells (WBC) that is typically evident by day 3 post infection (PI). In infections with typical BVDV field strains WBC counts decrease until days 6-9 PI and then return to baseline values. In infections with enhanced virulence BVDV, WBC counts may continue to decline through day 14. In this study, the lymph nodes and thymus of non-infected neonatal calves and neonatal calves infected 14 days previously with either a BVDV of typical virulence or one of enhanced virulence were compared. It was found that while calves, infected with the typical virulence BVDV, had cleared BVDV, and WBC counts had returned to near baseline, the number of B-B7(+) cells in lymph nodes were reduced whereas numbers of CD4(+) cells were increased as compared to control calves. In contrast, calves infected with the high virulence strain, had not cleared the virus by day 14 and WBC counts had not returned to pre-exposure levels. Furthermore, these calves had more substantial deficits of B-B7(+) and CD4(+) cell subpopulations, compared to calves infected with a typical virulence strain. There were also an increased number of macrophages observed in both lymphoid tissues examined. The thymuses from both groups of BVDV-infected calves were significantly smaller than non-infected age matched calves. The reduction in size was accompanied by a significant depletion of the thymic cortex. These results indicate that regardless of the virulence of the infecting BVDV, infection leaves neonatal calves with deficits in specific lymphocyte subsets and lymphoid tissues that could have long-term immunosuppressive implications.
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Raya AI, Gomez-Villamandos JC, Bautista MJ. Role of thymic epithelial cells in lymphoid depletion after experimental infection with the noncytopathogenic BVDV1 strain 7443. Vet Pathol 2014; 52:291-4. [PMID: 24842487 DOI: 10.1177/0300985814535610] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Thymic epithelial cells could play an important role in lymphoid depletion during bovine viral diarrhea virus (BVDV) infection. To evaluate this hypothesis, we examined proliferation of lymphocytes, expression of cytokeratins by thymic epithelial cells, and ultrastructural features at sequential time points after experimental infection of colostrum-deprived calves with the noncytopathogenic BVDV1 strain 7443. Ten clinically healthy Friesian calves were used. Eight were inoculated with the virus, and 2 were used as uninfected controls. Calves were sedated and euthanized in batches between 3 and 14 days postinoculation. At necropsy, thymus samples were collected for structural, immunohistochemical, and ultrastructural study. Thymic lymphoid depletion was accompanied by a decrease in lymphocyte proliferation and immunohistochemical and ultrastructural changes in thymic epithelial cells. Immunohistochemical and ultrastructural results reflect a disturbance of the thymic epithelial cell network, which may explain the decrease in lymphocyte proliferation by defective thymocyte-epithelial cell interactions.
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Affiliation(s)
- A I Raya
- Department of Animal Medicine and Surgery,
| | - J C Gomez-Villamandos
- Department of Comparative Pathology, University of Cordoba-Agrifood Campus of International Excellence (ceiA3), Córdoba, Spain
| | - M J Bautista
- Department of Comparative Pathology, University of Cordoba-Agrifood Campus of International Excellence (ceiA3), Córdoba, Spain
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24
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Palomares RA, Brock KV, Walz PH. Differential expression of pro-inflammatory and anti-inflammatory cytokines during experimental infection with low or high virulence bovine viral diarrhea virus in beef calves. Vet Immunol Immunopathol 2014; 157:149-54. [DOI: 10.1016/j.vetimm.2013.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 10/15/2013] [Accepted: 12/01/2013] [Indexed: 10/25/2022]
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Abstract
Bovine viral diarrhea virus (BVDV) continues to be of economic significance to the livestock industry in terms of acute disease and fetal loss. Many of the lesions relating to BVDV infection have been well described previously. The virus is perpetuated in herds through the presence of calves that are persistently infected. Relationships between various species and biotypes of BVDV and host defenses are increasingly understood. Understanding of the host defense mechanisms of innate immunity and adaptive immunity continues to improve, and the effects of the virus on these immune mechanisms are being used to explain how persistent infection develops. The noncytopathic biotype of BVDV plays the major role in its effects on the host defenses by inhibiting various aspects of the innate immune system and creation of immunotolerance in the fetus during early gestation. Recent advances have allowed for development of affordable test strategies to identify and remove persistently infected animals. With these improved tests and removal strategies, the livestock industry can begin more widespread effective control programs.
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Affiliation(s)
- B. W. Brodersen
- Nebraska Veterinary Diagnostic Center, University of Nebraska–Lincoln, Lincoln, NE, USA
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26
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Wang W, Shi X, Tong Q, Wu Y, Xia MQ, Ji Y, Xue W, Wu H. A bovine viral diarrhea virus type 1a strain in China: isolation, identification, and experimental infection in calves. Virol J 2014; 11:8. [PMID: 24444389 PMCID: PMC3901005 DOI: 10.1186/1743-422x-11-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/17/2014] [Indexed: 11/10/2022] Open
Abstract
Background Bovine viral diarrhea virus (BVDV) is one of the most important pathogens in cattle. Previously, BVDV sub-genotypes of 1b, 1c, 1d, and 1 m were detected in China. However, isolation of BVDV type 1a from cattle has not been reported in China. In 2010, twenty nasal swabs and blood samples were collected from the cattle suspected BVDV infection in Henan province, China. A BVDV isolate was isolated using cell culture, and the pathogenesis of the virus isolate was studied. Methods Virus isolation was performed on MDBK cells. The virus identification was conducted by RT-PCR, neutralization test and immunofluorescence assay. In order to determine the genotype of the newly isolated virus, the 5′ un-translated region (5′UTR) of the virus isolate was cloned, sequenced and phylogenetically analyzed. To evaluate the virulence of the virus isolate, four BVDV sero-negative calves were intranasally inoculated with the virus suspension. Rectal temperatures and clinical signs were recorded daily. Blood samples were analyzed for changes in white blood cell counts, and tissue samples were taken for histopathology analysis. Results A new isolate of bovine viral diarrhea virus (BVDV), named HN01, was isolated from the nasal swabs using MDBK cell culture. The HN01 strain caused cytopathic effect (CPE) in MDBK cell cultures after two passages. The virus specifically reacted to BVDV1-specific monoclonal antibody in an immunofluorescence assay. A fragment of 288 bp of genome from this isolate was amplified by the RT-PCR. Phylogenetic analysis of 5′UTR indicated that the virus was BVDV 1a. In the pathogenesis study, four calves experimentally infected with the BVDV strain developed depression, cough and other clinical signs. Calves showed high temperature over 40°C, and white blood cell counts dropped more than 40%. Conclusions A new subgenotype 1a strain of BVDV was firstly isolated from dairy cattle in China. The experimental infection showed that the virus was moderate pathogenic to cattle and can be used as a BVDV challenge virus to evaluate the efficacy of BVDV vaccines in the target animals.
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Affiliation(s)
| | | | | | | | | | | | | | - Hua Wu
- Institute of Special Economic Animal and Plant Science, CAAS, No, 4899, Juye Street, 130122 Changchun, PR China.
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Risalde MA, Molina V, Sónchez-Cordón PJ, Pedrera M, Romero-Palomo F, Bautista MJ, Moreno A, Gómez-Villamandos JC. Comparison of pathological changes and viral antigen distribution in tissues of calves with and without preexisting bovine viral diarrhea virus infection following challenge with bovine herpesvirus-1. Am J Vet Res 2013; 74:598-610. [PMID: 23531068 DOI: 10.2460/ajvr.74.4.598] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To compare pathological changes and viral antigen distribution in tissues of calves with and without preexisting subclinical bovine viral diarrhea virus (BVDV) infection following challenge with bovine herpesvirus-1 (BHV-1). ANIMALS 24 Friesian calves. PROCEDURES 12 calves were inoculated intranasally with noncytopathic BVDV-1a; 12 days later, 10 of these calves were challenged intranasally with BHV-1 subtype 1. Two calves were euthanized before and 1, 2, 4, 7, or 14 days after BHV-1 inoculation. Another 10 calves were inoculated intranasally with BHV-1 only and euthanized 1, 2, 4, 7, or 14 days later. Two calves were inoculated intranasally with virus-free tissue culture fluid and euthanized as negative controls. Pathological changes and viral antigen distribution in various tissue samples from calves with and without BVDV infection (all of which had been experimentally inoculated with BHV-1) were compared. RESULTS Following BHV-1 challenge, calves with preexisting subclinical BVDV infection had earlier development of more severe inflammatory processes and, consequently, more severe tissue lesions (limited to lymphoid tissues and respiratory and digestive tracts) and greater dissemination of BHV-1, compared with calves without preexisting BVDV infection. Moreover, coinfected calves had an intense lymphoid depletion in the Peyer patches of the ileum as well as the persistence of BVDV in target organs and the reappearance of digestive tract changes during disease progression. CONCLUSIONS AND CLINICAL RELEVANCE In calves, preexisting infection with BVDV facilitated the establishment of BHV-1 infection, just as the presence of BHV-1 favors BVDV persistence, thereby synergistically potentiating effects of both viruses and increasing the severity of the resultant clinical signs.
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Affiliation(s)
- María A Risalde
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba-Agrifood Campus of International Excellence (ceiA3), Edificio Sanidad Animal, Campus de Rabanales, 14014, Córdoba, Spain
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Ridpath JF, Falkenberg SM, Bauermann FV, VanderLey BL, Do Y, Flores EF, Rodman DM, Neill JD. Comparison of acute infection of calves exposed to a high-virulence or low-virulence bovine viral diarrhea virus or a HoBi-like virus. Am J Vet Res 2013; 74:438-42. [DOI: 10.2460/ajvr.74.3.438] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Expression of type I interferon-induced antiviral state and pro-apoptosis markers during experimental infection with low or high virulence bovine viral diarrhea virus in beef calves. Virus Res 2013; 173:260-9. [PMID: 23458997 DOI: 10.1016/j.virusres.2013.02.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 02/01/2013] [Accepted: 02/20/2013] [Indexed: 12/23/2022]
Abstract
The objective of this study was to compare the mRNA expression of host genes involved in type-I interferon-induced antiviral state (IFN-α, IFN-β, Mx-1, PKR, OAS-1 and ISG-15), and apoptosis (caspase-3, -8, and -9), after experimental infection of beef calves with low or high virulence noncytopathic (ncp) bovine viral diarrhea virus (BVDV) strains. Thirty BVDV-naïve, clinically normal calves were randomly assigned to three groups. Calves were intranasally inoculated with low (LV; n=10, strain SD-1) or high (HV; n=10, strain 1373) virulence ncp BVDV or BVDV-free cell culture medium (Control, n=10). Quantitative RT-PCR was used to determine the target gene expression in tracheo-bronchial lymph nodes and spleen 5 days after infection. Interferon-α and -β mRNA levels were up-regulated in tracheo-bronchial lymph nodes (P<0.05) in the HV group, but not in the LV group, compared with the control group. There was an up-regulation of type I interferon-induced genes in spleen and tracheo-bronchial lymph nodes of HV and LV groups, compared with the control group (P<0.01). mRNA levels of OAS-1 and ISG-15 were significantly higher in LV than HV calves (P<0.05). A significant up-regulation of caspase-8 and -9 was observed in tracheo-bronchial lymph nodes in the LV group (P=0.01), but not in the HV group. In conclusion, experimental infection with either high or low virulence BVDV strains induced a significant expression of the type I interferon-induced genes in beef calves. There was a differential expression of some interferon-induced genes (OAS-1 and ISG-15) and pro-apoptosis markers based on BVDV virulence and genotype.
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Chase CCL. The impact of BVDV infection on adaptive immunity. Biologicals 2012; 41:52-60. [PMID: 23137817 DOI: 10.1016/j.biologicals.2012.09.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 09/20/2012] [Accepted: 09/21/2012] [Indexed: 11/29/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV) causes immunosuppression of the adaptive immune response. The level of suppression of the adaptive immune response is strain dependent. The early events of antigen presentation require activation of toll-like receptors that results in the release of pro-inflammatory cytokines. Non-cytopathic (ncp) BVDV infection stimulates cytokines from macrophages in vitro but the effect of BVDV infection in vivo on macrophages or in vitro with monocytes is not clear. Antigen presentation is decreased and co-stimulatory molecules are down regulated. T-lymphocytes numbers are reduced following BVDV infection in a strain dependent manner. There is recruitment of lymphocytes to the bronchial alveolar space following cytopathic (cp) BVDV infection. Depletion of T-lymphocytes occurs in the lymphoid tissue and is strain dependent. BVDV cp T-lymphocyte responses appear to be primarily a T helper 1 response while the response following ncp BVDV induces a T helper 2 response. Cytotoxic T-lymphocytes (CTL), an important BVDV defense mechanism are compromised. The major neutralizing antigens are well characterized but cross-protection between strains is variable. PI animals have normal adaptive immune responses with the exception of the PI strain immunotolerance and mucosal disease may be a function of the level of gamma delta T cells.
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Affiliation(s)
- Christopher C L Chase
- Department of Veterinary and Biomedical Sciences, PO Box 2175, South Dakota State University, Brookings, SD 57007, USA.
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31
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Molina V, Risalde MA, Sánchez-Cordón PJ, Romero-Palomo F, Pedrera M, Garfia B, Gómez-Villamandos JC. Cell-Mediated Immune Response During Experimental Acute Infection with Bovine Viral Diarrhoea Virus: Evaluation of Blood Parameters. Transbound Emerg Dis 2012; 61:44-59. [DOI: 10.1111/tbed.12002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Indexed: 11/27/2022]
Affiliation(s)
- V. Molina
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
| | - M. A. Risalde
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
| | - P. J. Sánchez-Cordón
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
| | - F. Romero-Palomo
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
| | - M. Pedrera
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
| | - B. Garfia
- Garfia Veterinary Medicine Laboratory S.L.; Polígono Industrial Tecnocórdoba; C/Varsovia, 53, 14014 Córdoba Spain
| | - J. C. Gómez-Villamandos
- Department of Comparative Pathology; Faculty of Veterinary Medicine; University of Córdoba-Agrifood Campus of International Excellence (ceiA3); Edificio Sanidad Animal, Campus de Rabanales; 14014 Córdoba Spain
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Abstract
Providing acquired immune protection against infection with bovine viral diarrhea viruses (BVDV) is challenging due to the heterogeneity that exists among BVDV strains and the ability of the virus to infect the fetus and establish persistent infections. Both modified live and killed vaccines have been shown to be efficacious under controlled conditions. Both humoral and cellular immune responses are protective. Following natural infection or vaccination with a modified live vaccine, the majority of the B cell response (as measured by serum antibodies) is directed against the viral proteins E2 and NS2/3, with minor responses against the Erns and E1 proteins. Vaccination with killed vaccines results in serum antibodies directed mainly at the E2 protein. It appears that the major neutralizing epitopes are conformational and are located within the N-terminal half of the E2 protein. While it is thought that the E2 and NS2/3 proteins induce protective T cell responses, these epitopes have not been mapped. Prevention of fetal infections requires T and B cell response levels that approach sterilizing immunity. The heterogeneity that exists among circulating BVDV strains, works against establishing such immunity. Vaccination, while not 100% effective in every individual animal, is effective at the herd level.
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Affiliation(s)
- Julia F Ridpath
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, ARS/USDA, PO Box 70, 1920 Dayton Avenue, Ames, IA 50010, USA.
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33
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Pedrera M, Gómez-Villamandos JC, Molina V, Risalde MA, Rodríguez-Sánchez B, Sánchez-Cordón PJ. Quantification and determination of spread mechanisms of bovine viral diarrhoea virus in blood and tissues from colostrum-deprived calves during an experimental acute infection induced by a non-cytopathic genotype 1 strain. Transbound Emerg Dis 2011; 59:377-84. [PMID: 22151958 DOI: 10.1111/j.1865-1682.2011.01281.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To detect and monitor the sequential changes in virus levels, a reverse transcription quantitative real-time polymerase chain reaction assay using a TaqMan probe was carried out on frozen blood and tissues samples collected from calves experimentally infected with a non-cytopathic Bovine viral diarrhoea virus (BVDV) genotype 1 strain. Blood samples were collected among days 1-14 post-inoculation (p.i). On day 3 p.i, viral RNA was detected in blood samples from six of the eight inoculated animals. Viral RNA was detected in all remaining inoculated animals between 5 and 12 days p.i. The levels of viral RNA increased along the experiment, with a maximal peak between 6 and 9 days p.i. Analysis of virus load in tissues collected from calves euthanized on days 3, 6, 9 and 14 p.i displayed that BVDV was detected on day 3 p.i, being especially abundant in tonsils and ileocaecal valve, highlighting the role of tonsils as the main earliest viral replication sites as well as the principal source for virus spread to other lymphoid tissues and visceral organs. Coinciding with the highest viraemia levels, the highest viral loads were recorded at 9 days p.i. in tonsils, ileal lymph nodes, distal ileum and spleen, showing the main role of these secondary lymphoid organs in the pathogenic mechanisms of BVDV. However, virus levels in the liver and lung increased only towards the end of the infection. This fact could influence in the appearance of bovine respiratory diseases because of the capacity of BVDV for enhancing susceptibility to secondary infections.
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Affiliation(s)
- M Pedrera
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba- Agrifood Excellence International Campus (ceiA3), Edificio Sanidad Animal, Campus de Rabanales, Córdoba, Spain
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Hepatic immune response in calves during acute subclinical infection with bovine viral diarrhoea virus type 1. Vet J 2011; 190:e110-e116. [DOI: 10.1016/j.tvjl.2011.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 03/01/2011] [Accepted: 03/03/2011] [Indexed: 11/22/2022]
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35
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Risalde MA, Molina V, Sánchez-Cordón PJ, Pedrera M, Panadero R, Romero-Palomo F, Gómez-Villamandos JC. Response of proinflammatory and anti-inflammatory cytokines in calves with subclinical bovine viral diarrhea challenged with bovine herpesvirus-1. Vet Immunol Immunopathol 2011; 144:135-43. [PMID: 21856021 DOI: 10.1016/j.vetimm.2011.07.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Revised: 07/19/2011] [Accepted: 07/27/2011] [Indexed: 12/30/2022]
Abstract
The aim of this work was to investigate the susceptibility of calves infected with bovine viral diarrhea virus (BVDV) against secondary infections. For this purpose, the profile of cytokines implicated in the immune response of calves experimentally infected with a non-cytopathic strain of BVDV type-1 and challenged with bovine herpesvirus 1.1 (BHV-1.1) was evaluated in comparison with healthy animals challenged only with BHV-1.1. The immune response was measured by serum concentrations of cytokines (IL-1β, TNFα, IFNγ, IL-12, IL-4 and IL-10), acute phase proteins (haptoglobin, serum amyloid A and fibrinogen) and BVDV and BHV-1.1 specific antibodies. BVDV-infected calves displayed a great secretion of TNFα and reduced production of IL-10 following BHV-1 infection, leading to an exacerbation of the inflammatory response and to the development of more intense clinical symptoms and lesions than those observed in healthy animals BHV-1-inoculated. A Th1 immune response, based on IFNγ production and on the absence of significant changes in IL-4 production, was observed in both groups of BHV-1-infected calves. However, whereas the animals inoculated only with BHV-1 presented an IFNγ response from the start of the study and high expression of IL-12, the BVDV-infected calves showed a delay in the IFNγ production and low levels of IL-12. This alteration in the kinetic and magnitude of these cytokines, involved in cytotoxic mechanisms responsible for limiting the spread of secondary pathogens, facilitated the dissemination of BHV-1.1 in BVDV-infected calves.
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Affiliation(s)
- M A Risalde
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba-Agrifood Campus of International Excellence (ceiA3), Campus de Rabanales, 14014, Córdoba, Spain
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Raya AI, Gomez-Villamandos JC, Sánchez-Cordón PJ, Bautista MJ. Virus Distribution and Role of Thymic Macrophages During Experimental Infection With Noncytopathogenic Bovine Viral Diarrhea Virus Type 1. Vet Pathol 2011; 49:811-8. [DOI: 10.1177/0300985811414031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thymic depletion, presence of viral antigen, and changes in distribution and cytokine production of thymic macrophages were investigated in calves experimentally infected with a noncytopathogenic bovine viral diarrhea virus type (BVDV) 1 strain. Ten clinically healthy colostrum-deprived calves were used. Eight calves were inoculated with the virus and two were used as uninfected controls. Calves were sedated and euthanized in batches between 3 and 14 days postinoculation. At necropsy, thymus samples were collected for structural, immunohistochemical, and ultrastructural study and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling). From 6 days postinoculation, the thymic cortex was multifocally depleted with increased frequency of pyknosis and karyorrhexis, suggestive of apoptosis and confirmed by the TUNEL technique. Although the onset of lymphoid depletion was coincident with the detection of viral antigen by immunohistochemistry, the number of infected lymphocytes was very low through the experiment. There was an increase in number of macrophages in cortex and medulla, accompanied by ultrastructural changes indicative of phagocyte activation, and a decrease in cells expressing tumor necrosis factor-alpha (TNF-α) and IL-1α. These results suggest that the increase in number of these cells could be related to phagocytosis of cell debris and apoptotic lymphocytes. Furthermore, the results imply that, in contrast to the situation with classical swine fever virus, the lymphocyte apoptosis resulting from bovine viral diarrhea virus infection is not mediated by TNF-α or interleukin-1 alpha (IL-1α) production by virus-infected macrophages. This is the first study that describes this decrease in the number of thymic cells expressing TNF-α and IL-1α in cattle experimentally infected with bovine viral diarrhea virus type 1.
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Affiliation(s)
- A. I. Raya
- Department of Animal Medicine and Surgery, University of Cordoba, Cordoba, Spain
| | | | | | - M. J. Bautista
- Department of Pathology, University of Cordoba, Cordoba , Spain
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Pedrera M, Gómez-Villamandos JC, Risalde MA, Molina V, Sánchez-Cordón PJ. Characterization of apoptosis pathways (intrinsic and extrinsic) in lymphoid tissues of calves inoculated with non-cytopathic bovine viral diarrhoea virus genotype-1. J Comp Pathol 2011; 146:30-9. [PMID: 21612789 DOI: 10.1016/j.jcpa.2011.03.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 03/24/2011] [Accepted: 03/29/2011] [Indexed: 11/26/2022]
Abstract
Previous studies have shown that activation of effector caspase-3 is associated with the apoptosis of lymphocytes occurring during infection with bovine viral diarrhoea virus (BVDV); however, the regulation of the apoptosis pathways that induce cell death via activation of effector caspase-3 has not yet been clarified. The aim of this study was to examine immunohistochemically the expression of cleaved caspase (CCasp)-8 (initiator caspase of the extrinsic pathway), CCasp9 (initiator caspase of the intrinsic pathway) and Bcl-2 (an anti-apoptotic marker) in gut-associated lymphoid tissue (GALT) of the ileum from calves inoculated with a non-cytopathic strain of BVDV genotype-1. CCasp8 had similar expression to that of CCasp3. In interfollicular T-cell areas there was moderate apoptosis and evidence of moderate activation of initiator caspase-8. In B-cell follicles there was marked lymphocyte apoptosis and evidence of intense caspase-8 activation, highlighting the potentially major role of the extrinsic pathway in lymphocyte apoptosis in the GALT during BVDV infection. Additionally, there was a significant decrease in the number of CCasp9(+) cells from the start of the experiment and this was linked to inactivation of caspase-9. Therefore, the intrinsic pathway may play only a minor role in the induction of lymphocyte apoptosis. Finally, the observed overexpression of Bcl-2 protein could play a major role in protecting lymphocytes in the T-cell areas against apoptosis, while low levels of Bcl-2 expression could be associated with the follicular lymphocyte apoptosis occurring during BVDV infection.
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Affiliation(s)
- M Pedrera
- Department of Comparative Pathology, Veterinary Faculty, University of Córdoba, Edificio Sanidad Animal, Campus de Rabanales, 14014 Córdoba, Spain
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Ridpath JF, Dominowski P, Mannan R, Yancey R, Jackson JA, Taylor L, Mediratta S, Eversole R, Mackenzie CD, Neill JD. Evaluation of three experimental bovine viral diarrhea virus killed vaccines adjuvanted with combinations of Quil A cholesterol and dimethyldioctadecylammonium (DDA) bromide. Vet Res Commun 2010; 34:691-702. [PMID: 20872289 DOI: 10.1007/s11259-010-9442-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2010] [Indexed: 11/29/2022]
Abstract
Bovine viral diarrhea virus (BVDV) infections cause respiratory, reproductive, and enteric disease in cattle. Vaccination raises herd resistance and limits the spread of BVDV among cattle. Both killed and modified live vaccines against BVDV are available. While modified live vaccines elicit an immune response with a broader range and a longer duration of immunity, killed vaccines are considered to be safer. One way to improve the performance of killed vaccines is to develop new adjuvants. The goal of this research was evaluate new adjuvants, consisting of combinations of Quil A cholesterol and dimethyldioctadecylammonium (DDA) bromide, for use in killed vaccines. Responses to three novel killed vaccines, using combinations of Quil A and DDA as adjuvants, were compared to responses to a commercial modified live and a commercial killed vaccine. Vaccination response was monitored by measuring viral neutralizing antibodies (VN) levels and by response to challenge. All three novel vaccines were efficacious based on reduction in virus isolation, pyrexia, and depression. Compared to a commercial killed vaccine, the three novel vaccines elicited higher VN levels and reduced injection site inflammation.
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Affiliation(s)
- Julia F Ridpath
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Avenue, P.O. Box 70, Ames, IA 50010, USA.
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The Contribution of Infections with Bovine Viral Diarrhea Viruses to Bovine Respiratory Disease. Vet Clin North Am Food Anim Pract 2010; 26:335-48. [DOI: 10.1016/j.cvfa.2010.04.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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40
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Ridpath JF. Bovine viral diarrhea virus: global status. Vet Clin North Am Food Anim Pract 2010; 26:105-21, table of contents. [PMID: 20117546 DOI: 10.1016/j.cvfa.2009.10.007] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Despite the success of regional bovine viral diarrhea viruses (BVDV) eradication programs, infections remain a source of economic loss for producers. The wide variation among BVDV results in differences in genotype, biotype, virulence, and types of infections. BVDV infect a range of domestic and wild ruminants. Clinical presentation varies depending on strain of virus, species of host, immune status of host, reproductive status of host, age of host, and concurrent infections. Recent advances in BVDV research and diagnostics have led to the development of regional eradication/control programs, the most efficacious of which focus on biosecurity, surveillance, and control.
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Affiliation(s)
- Julia F Ridpath
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA 50010, USA.
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41
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Walz P, Grooms D, Passler T, Ridpath J, Tremblay R, Step D, Callan R, Givens M. Control of Bovine Viral Diarrhea Virus in Ruminants. J Vet Intern Med 2010; 24:476-86. [DOI: 10.1111/j.1939-1676.2010.0502.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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42
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Apoptosis in lymphoid tissues of calves inoculated with non-cytopathic bovine viral diarrhea virus genotype 1: activation of effector caspase-3 and role of macrophages. J Gen Virol 2009; 90:2650-2659. [DOI: 10.1099/vir.0.012021-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The mechanisms responsible for lymphocyte apoptosis in bovine viral diarrhoea have not yet been clarified. Previous work suggests that bovine viral diarrhea virus (BVDV) is only directly responsible for the destruction of a small number of lymphocytes. The aim of this study was to clarify, in vivo, the role of macrophages in lymphocyte destruction through indirect mechanisms linked to the biosynthetic activation of these immunocompetent cells on ileal Peyer's patches, as well as the distribution and quantification of apoptosis. Eight colostrum-deprived calves were inoculated intranasally with a non-cytopathic strain of BVDV genotype 1 and killed in batches of two at 3, 6, 9 and 14 days post-inoculation (p.i.). The progressive depletion of Peyer's patches was found to be due to massive lymphocyte apoptosis, with an increase in cleaved caspase-3 and TUNEL-positive cells. Lymphoid depletion was accompanied, from 3 days p.i., by a significant rise in macrophage numbers both in lymphoid follicles and in interfollicular areas. Some macrophages showed signs of viral infection, together with subcellular changes indicative of phagocyte activation and, in some cases, of secretory activity. However, the number of macrophages that showed positive immunostaining for tumour necrosis factor-α and interleukin-1α, cytokines with a proven ability to induce apoptosis, remained low throughout the experiment in lymphoid follicles, where most apoptotic cells were found. These results thus appear to rule out a major involvement of macrophages and macrophage-secreted chemical mediators in the apoptosis of follicular B lymphocytes during BVDV infection.
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Morphological Changes and Virus Distribution in the Ileum of Colostrum-Deprived Calves Inoculated with Non-Cytopathic Bovine Viral Diarrhoea Virus Genotype-1. J Comp Pathol 2009; 141:52-62. [DOI: 10.1016/j.jcpa.2009.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 02/19/2009] [Accepted: 03/12/2009] [Indexed: 11/18/2022]
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Ridpath JF, Neill JD, Peterhans E. Impact of variation in acute virulence of BVDV1 strains on design of better vaccine efficacy challenge models. Vaccine 2007; 25:8058-66. [DOI: 10.1016/j.vaccine.2007.09.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 09/04/2007] [Accepted: 09/05/2007] [Indexed: 11/28/2022]
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Bendfeldt S, Ridpath JF, Neill JD. Activation of cell signaling pathways is dependant on the biotype of bovine viral diarrhea viruses type 2. Virus Res 2007; 126:96-105. [PMID: 17376555 DOI: 10.1016/j.virusres.2007.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 01/29/2007] [Accepted: 02/02/2007] [Indexed: 10/23/2022]
Abstract
Bovine viral diarrhea virus (BVDV), a pestivirus of the Flaviviridae family, is an economically important cattle pathogen with a worldwide distribution. Besides the segregation into two distinct species (BVDV1/BVDV2) two different biotypes, a cytopathic (cp) and a noncytopathic (ncp) biotype, are distinguished based on their behavior in epithelial cell cultures. One of the most serious forms of BVDV infection affecting immunocompetent animals of all ages is severe acute BVD (sa BVD) which is caused by highly virulent ncp BVDV2 strains. Previous studies revealed that these highly virulent ncp viruses cause cell death in a lymphoid cell line (BL3) which is not clearly associated with typical apoptotic changes (e.g. PARP cleavage) observed after infection with cp BVDV. To further characterize the underlying molecular mechanisms, we first analyzed the role of the mitochondria and caspases as key mediators of apoptosis. Compared to infection with cp BVDV2, infection with highly virulent ncp BVDV2 resulted in a delayed and less pronounced disruption of the mitochondrial transmembrane potential (DeltaPsi(m)) and a weaker activation of the caspase cascade. In contrast, infection with low virulence ncp BVDV2 showed no significant differences from the uninfected control cells. Since different pro- and anti-apoptotic cellular signaling pathways may become activated upon virus infection, we compared the effect of different BVDV2 strains on cellular signaling pathways in BL3 cells. Stress-mediated p38 MAPK phosphorylation was detected only in cells infected with cp BVDV2. Interestingly, infection with highly virulent ncp BVDV2 was found to influence the phosphoinositide 3-kinase (PI3K)-Akt pathway. This indicates that BL3 cells respond differently to infection with BVDV depending on virulence and biotype.
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Affiliation(s)
- S Bendfeldt
- National Animal Disease Center, ARS, USDA, Ames, IA, USA
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Liebler-Tenorio EM, Kenklies S, Greiser-Wilke I, Makoschey B, Pohlenz JF. Incidence of BVDV1 and BVDV2 Infections in Cattle Submitted for Necropsy in Northern Germany. ACTA ACUST UNITED AC 2006; 53:363-9. [PMID: 17010039 DOI: 10.1111/j.1439-0450.2006.00992.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The incidence of bovine viral diarrhoea virus (BVDV) 1 and 2 infections was determined in calves, young cattle and older cattle with signs of mucosal disease (MD) submitted for necropsy to three laboratories in Northern Germany between June 2000 and May 2001. At necropsy, tonsils, retropharyngeal lymph nodes, mesenteric lymph nodes, ileal Peyer's patch and spleen were collected and examined by immunohistochemistry and virus isolation. From 311 animals examined, 30 (9.6%) were positive for BVDV. All viral isolates were typed by polymerase chain reaction after reverse transcription using species-specific primers and determined to be BVDV1. Based on the distribution of lesions and viral antigen, animals with MD, persistent infection (PI) and acute, transient infection could be distinguished. Twelve of the positive animals had characteristic signs of MD: severe diarrhoea, erosive to ulcerative lesions throughout the digestive tract and severe depletion of all lymphoid tissues. Viral antigen was present in all tissues and cell types, but particularly in depleted lymphoid follicles and altered epithelium. In seven calves, viral antigen was detectable in all tissues and cell types, but lesions were mild or missing. This is typical for PI. The remaining 11 calves most likely represent animals with acute, transient infection. Distribution of antigen was more variable, predominantly restricted to lymphoid follicles and often not seen in all tissues examined. Clinical findings were combined bronchopneumonia and enteritis. The detection of BVDV1 in young calves with pneumonia and enteritis emphasizes the importance of BVDV1 and not only BVDV2 for severe respiratory and enteric diseases of calves.
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Affiliation(s)
- E M Liebler-Tenorio
- Friedrich-Loeffler-Institute, Federal Research Center for Animal Health, Standort Jena, Jena.
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Ridpath JF, Bendfeldt S, Neill JD, Liebler-Tenorio E. Lymphocytopathogenic activity in vitro correlates with high virulence in vivo for BVDV type 2 strains: Criteria for a third biotype of BVDV. Virus Res 2006; 118:62-9. [PMID: 16384618 DOI: 10.1016/j.virusres.2005.11.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 11/05/2005] [Accepted: 11/18/2005] [Indexed: 12/01/2022]
Abstract
Two biotypes of bovine viral diarrhea viruses (BVDV), cytopathic (cp) and noncytopathic (ncp), are recognized based on their activity in cultured epithelial cells. Biotype does not correlate to virulence in acute infections as BVDV strains associated with severe acute BVD outbreaks are all noncytopathic based on their growth characteristics in cultured epithelial cells. Previous studies have shown that acute infections with highly virulent BVDV result in depletion of cells in lymphoid tissues. In this study, flow cytometry demonstrated that infection with a highly virulent BVDV strain was associated with a pronounced reduction in circulating white blood cells (WBC) and increased numbers of apoptotic and necrotic circulating WBC in vivo. Infection with low virulence BVDV did not result in a significant increase in death of circulating WBC. Thus, there appeared to be a correlation between depletion of circulating WBC and virulence. To study the interaction of BVDV strains with lymphoid cells in the laboratory, we developed an in vitro model that used a bovine lymphoid cell line (BL-3 cells). Using this model, it was found that while BVDV strains are segregated into two biotypes based on their activity in cultured epithelial cells, they may be segregated into three biotypes based on their activity in cultured lymphoid cells. These three biotypes are noncytopathogenic (no obvious effects on the viability of either cultured epithelial or lymphoid cells), cytopathogenic (cytopathic effect and cell death in both cultured epithelial and lymphoid cells within 48 h of infection) and lymphocytopathogenic (no effect on cultured epithelial cells, however, cell death in cultured lymphoid cells is observed within 5 days of infection). The proposed lymphocytopathic biotype correlates with high virulence in acute infections in vivo. Cell death caused by the lymphocytopathogenic biotype was not associated with changes typically seen with cytopathic viruses grown in cultured epithelial cells (e.g. changes in processing of the NS2/3 protein observed within 24h post infection, crenation and breakdown of cell integrity within the first 48 h post infection). These data suggest that the cytopathic effect induced in cultured lymphoid cells by a ncp highly virulent BVDV strain may occur by a different mechanism than the cytopathic effect induced by cp BVDV strains.
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Affiliation(s)
- Julia F Ridpath
- Virus and Prion Diseases of Livestock Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA 50010, USA.
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Ridpath JF. Practical significance of heterogeneity among BVDV strains: Impact of biotype and genotype on U.S. control programs. Prev Vet Med 2005; 72:17-30; discussion 215-9. [PMID: 16183156 DOI: 10.1016/j.prevetmed.2005.08.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In the early 1990s research groups in North America noted that a newly recognized severe acute form of bovine viral diarrhea virus infection, referred to as hemorrhagic syndrome or severe acute BVDV (SA BVDV), was associated with a genetically distinct subgroup of BVDV strains. This new subgroup was named BVDV genotype 2 or BVDV2. All BVDV strains previously characterized in the literature belonged to a separate genotype, BVDV1. However, not all strains identified as BVDV2 were associated with severe acute infections. If I did this deletion, I did not mean to do it. I think it was already here, though. I see there are some other big edits that I did not do; fine. Hollis subsequent surveys of BVDV strains isolated from clinical submissions to diagnostic laboratories and contaminated fetal calf serum suggested that the ratio of BVDV2 to BVDV1 strains in the U.S. approached 50%. Further, while antigenic cross reactivity is seen between BVDV1 and BVDV2 strains, a log or more difference is typically observed in titers against viruses from different genotypes. These observations prompted vaccine manufacturers in North America to produce vaccines against BVDV that contained antigens from both BVDV1 and BVDV2 strains. Under experimental conditions, these new vaccines offered improved protection against type 2 strains, however field data are still insufficient to assess their efficacy in practice. The BVDV genotypes may also be segregated into subgenotypes. Two subgenotypes of both BVDV1 (BVDV1a and BVDV1b) and BVDV2 (BVDV2a and BVDV2b) have been reported in North American. BVDV2a predominates with BVDV2b isolation a rare event. In contrast, BVDV1a and BVDV1b are both commonly isolated. Antigenic differences observed between strains from the BVDV1a and BVDV1b subgenotypes have led to the suggestion that protection may be improved by inclusion of strains from both BVDV1a and BVDV1b in vaccines in addition to BVDV2. The cost to benefit ratio of this proposal is currently a matter of debate.
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Affiliation(s)
- Julia F Ridpath
- Virus and Prion Diseases of Livestock Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 2300 Dayton Avenue, P.O. Box 70, Ames, IA 50010, USA.
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Chase CCL, Elmowalid G, Yousif AAA. The immune response to bovine viral diarrhea virus: a constantlychanging picture. Vet Clin North Am Food Anim Pract 2004; 20:95-114. [PMID: 15062477 DOI: 10.1016/j.cvfa.2003.11.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV) is one of the major immuno-suppressive viruses of cattle. The effect on the innate and acquired immune system is unique and results in dramatic immune dysfunction. BVDV infection also has the ability to cause persistent infection (PI) in the developing fetus. This Pl syndrome creates a requirement for high levels of BVDV immunity from vaccines to prevent these infections. BVDV vaccines and their future development continue to be an enigma in the control of BVDV.
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Affiliation(s)
- Christopher C L Chase
- Department of Veterinary Science, South Dakota State University, P.O. Box 2175, Brookings, SD 57007, USA.
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