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AbuEed L, Makundi I, Miyake A, Kawasaki J, Minoura C, Koshida Y, Nishigaki K. Feline Foamy Virus Transmission in Tsushima Leopard Cats (Prionailurus bengalensis euptilurus) on Tsushima Island, Japan. Viruses 2023; 15:v15040835. [PMID: 37112816 PMCID: PMC10146696 DOI: 10.3390/v15040835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/14/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Tsushima leopard cats (TLC; Prionailurus bengalensis euptilurus) only inhabit Tsushima Island, Nagasaki, Japan and are critically endangered and threatened by infectious diseases. The feline foamy virus (FFV) is widely endemic in domestic cats. Therefore, its transmission from domestic cats to TLCs may threaten the TLC population. Thus, this study aimed to assess the possibility that domestic cats could transmit FFV to TLCs. Eighty-nine TLC samples were screened, and FFV was identified in seven (7.86%). To assess the FFV infection status of domestic cats, 199 domestic cats were screened; 14.07% were infected. The phylogenetic analysis revealed that the FFV partial sequence from domestic cats and TLC sequences clustered in one clade, suggesting that the two populations share the same strain. The statistical data minimally supported the association between increased infection rate and sex (p = 0.28), indicating that FFV transmission is not sex dependent. In domestic cats, a significant difference was observed in FFV detection in feline immunodeficiency virus (p = 0.002) and gammaherpesvirus1 infection statuses (p = 0.0001) but not in feline leukemia virus infection status (p = 0.21). Monitoring FFV infection in domestic cats and TLC populations is highly recommended as part of TLC surveillance and management strategies.
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Occurrence of Equine Foamy Virus Infection in Horses from Poland. Viruses 2022; 14:v14091973. [PMID: 36146781 PMCID: PMC9504846 DOI: 10.3390/v14091973] [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: 08/10/2022] [Revised: 08/31/2022] [Accepted: 09/01/2022] [Indexed: 11/28/2022] Open
Abstract
Equine foamy virus (EFVeca) is a foamy virus of non-primate origin and among the least-studied members of this retroviral subfamily. By sequence comparison, EFVeca shows the highest similarity to bovine foamy virus. In contrast to simian, bovine or feline foamy viruses, knowledge about the epidemiology of EFVeca is still limited. Since preliminary studies suggested EFVeca infections among horses in Poland, we aimed to expand the diagnostics of EFVeca infections by developing specific diagnostic tools and apply them to investigate its prevalence. An ELISA test based on recombinant EFVeca Gag protein was developed for serological investigation, while semi-nested PCR for the detection of EFVeca DNA was established. 248 DNA and serum samples from purebred horses, livestock and saddle horses, Hucul horses and semi-feral Polish primitive horses were analyzed in this study. ELISA was standardized, and cut off value, sensitivity and specificity of the test were calculated using Receiver Operating Characteristic and Bayesian estimation. Based on the calculated cut off, 135 horses were seropositive to EFVeca Gag protein, while EFVeca proviral DNA was detected in 85 animals. The rate of infected individuals varied among the horse groups studied; this is the first report confirming the existence of EFVeca infections in horses from Poland using virus-specific tools.
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Sumiyoshi A, Kitao K, Miyazawa T. Genetic and biological characterization of feline foamy virus isolated from a leopard cat (Prionailurus bengalensis) in Vietnam. J Vet Med Sci 2021; 84:157-165. [PMID: 34880191 PMCID: PMC8810315 DOI: 10.1292/jvms.21-0550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Foamy viruses have been isolated from various mammals and show long-term co-speciation with their hosts. However, the frequent inter-species transmission of feline foamy viruses (FFVs) from
domestic cats to wild cats across genera has been reported. Because infectious molecular clones of FFVs derived from wild cats have not been available, whether there are specific
characteristics enabling FFVs to adapt to the new host species is still unknown. Here, we obtained the complete genome sequences of two FFV isolates (strains NV138 and SV201) from leopard
cats (Prionailurus bengalensis) in Vietnam and constructed an infectious molecular clone, named pLC960, from strain NV138. The growth kinetics of the virus derived from
pLC960 were comparable to those of other FFVs derived from domestic cats. Phylogenetic analysis revealed that these two FFVs from leopard cats are clustered in the same clade as FFVs from
domestic cats in Vietnam. Comparisons of the amino acid sequences of Env and Bet proteins showed more than 97% identity among samples and no specific amino acid substitutions between FFVs
from domestic cats and ones from leopard cats. These results indicate the absence of genetic constraint of FFVs for interspecies transmission from domestic cats to leopard cats.
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Affiliation(s)
- Aoi Sumiyoshi
- Laboratory of Virus-Host Coevolution, Institute for Frontier Life and Medical Sciences, Kyoto University
| | - Koichi Kitao
- Laboratory of Virus-Host Coevolution, Institute for Frontier Life and Medical Sciences, Kyoto University
| | - Takayuki Miyazawa
- Laboratory of Virus-Host Coevolution, Institute for Frontier Life and Medical Sciences, Kyoto University
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4
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Seroprevalence of feline foamy virus in domestic cats in Poland. J Vet Res 2021; 65:407-413. [PMID: 35111993 PMCID: PMC8775732 DOI: 10.2478/jvetres-2021-0059] [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: 10/12/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022] Open
Abstract
Abstract
Introduction
Feline foamy virus (FFVfca) is widespread and its prevalence in naturally infected domestic cats ranges between 30% and 80% worldwide. The infection is persistent, with a sustained antibody response in FFVfca-positive cats; however to date, no defined disease or clinical symptoms have been proved to be associated with it. The goal of the presented study was to determine the prevalence of FFVfca infection in domestic cats in Poland.
Material and Methods
A total of 223 serum samples collected from domestic cats were tested with a glutathione S-transferase capture ELISA test to detect antibodies specific to capsid (Gag), accessory (Bet) and envelope (Env) FFVfca antigens. A Western blot test was used to confirm the ELISA results.
Results
The cut-off value for the Gag antigen was established by calculation and evaluation with the immunoblotting assay. The cut-off values for Bet and Env were calculated from the reactivity of Gag-negative samples. The sera of 99 cats (44%) showed reactivity to Gag, those of 80 did so (35.9 %) to Bet, while only 56 samples (25%) were reactive to Env. Only 51 (22.9%) sera were positive for all antigens. The main diagnostic antigen was selected to be Gag. A statistically significant association was found between FFVfca status and the age of the cat.
Conclusions
This study proved the high seroprevalence of FFVfca in domestic cats in Poland for the first time and confirmed that adult cats are at higher FFVfca infection risk than preadult cats. Its results correspond to those reported from other countries.
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Moskaluk A, Nehring M, VandeWoude S. Serum Samples from Co-Infected and Domestic Cat Field Isolates Nonspecifically Bind FIV and Other Antigens in Enzyme-Linked Immunosorbent Assays. Pathogens 2021; 10:665. [PMID: 34071706 PMCID: PMC8226436 DOI: 10.3390/pathogens10060665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/05/2022] Open
Abstract
We evaluated enzyme-linked immunosorbent assay (ELISA) specificity for measuring seroantibody responses to two types of retroviral infections in domestic cats: feline immunodeficiency virus (FIV) and feline foamy virus (FFV). We compared the seroreactivity of specific pathogen-free (SPF) cat sera, sera from SPF cats inoculated with either FIV or FFV, and field isolates (e.g., shelter or privately owned cats). Sera from SPF cats experimentally infected with the cognate virus had significantly lower background in both FIV and FFV ELISAs compared to sera from negative field isolates. ELISA values for SPF cats exposed to either FIV or FFV tended to have higher OD values on the opposite ELISA antigen plate. FIV nonspecific background absorbance was greater than that of FFV, and 10 of 15 sera samples from FIV seronegative field samples were measured in the indeterminant range. These findings highlight that exposure to off-target pathogens elicit antibodies that may nonspecifically bind to antigens used in binding assays; therefore, validation using sera from SPF animals exposed during controlled infection results in the setting of a cutoff value that may be inappropriately low when applied to field samples. Our work also suggests that infection of domestic cats with pathogens other than FIV results in antibodies that cross-react with the FIV Gag antigen.
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Affiliation(s)
| | | | - Sue VandeWoude
- Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA; (A.M.); (M.N.)
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Dannemiller NG, Kechejian S, Kraberger S, Logan K, Alldredge M, Crooks KR, VandeWoude S, Carver S. Diagnostic Uncertainty and the Epidemiology of Feline Foamy Virus in Pumas (Puma concolor). Sci Rep 2020; 10:1587. [PMID: 32005906 PMCID: PMC6994588 DOI: 10.1038/s41598-020-58350-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 01/03/2020] [Indexed: 12/29/2022] Open
Abstract
Feline foamy virus (FFV) is a contact-dependent retrovirus forming chronic, largely apathogenic, infections in domestic and wild felid populations worldwide. Given there is no current ‘gold standard’ diagnostic test for FFV, efforts to elucidate the ecology and epidemiology of the virus may be complicated by unknown sensitivity and specificity of diagnostic tests. Using Bayesian Latent Class Analysis, we estimated the sensitivity and specificity of the only two FFV diagnostic tests available—ELISA and qPCR—as well as the prevalence of FFV in a large cohort of pumas from Colorado. We evaluated the diagnostic agreement of ELISA and qPCR, and whether differences in their diagnostic accuracy impacted risk factor analyses for FFV infection. Our results suggest ELISA and qPCR did not have strong diagnostic agreement, despite FFV causing a persistent infection. While both tests had similar sensitivity, ELISA had higher specificity. ELISA, but not qPCR, identified age to be a significant risk factor, whereas neither qPCR nor ELISA identified sex to be a risk factor. This suggests FFV transmission in pumas may primarily be via non-antagonistic, social interactions between adult conspecifics. Our study highlights that combined use of qPCR and ELISA for FFV may enhance estimates of the true prevalence of FFV and epidemiological inferences.
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Affiliation(s)
- Nicholas G Dannemiller
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA.
| | - Sarah Kechejian
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Simona Kraberger
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Kenneth Logan
- Colorado Parks and Wildlife, Montrose, Colorado, USA
| | | | - Kevin R Crooks
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania, Australia
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Kraberger S, Fountain-Jones NM, Gagne RB, Malmberg J, Dannemiller NG, Logan K, Alldredge M, Varsani A, Crooks KR, Craft M, Carver S, VandeWoude S. Frequent cross-species transmissions of foamy virus between domestic and wild felids. Virus Evol 2020; 6:vez058. [PMID: 31942245 PMCID: PMC6955097 DOI: 10.1093/ve/vez058] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Emerging viral outbreaks resulting from host switching is an area of continued scientific interest. Such events can result in disease epidemics or in some cases, clinically silent outcomes. These occurrences are likely relatively common and can serve as tools to better understand disease dynamics, and may result in changes in behavior, fecundity, and, ultimately survival of the host. Feline foamy virus (FFV) is a common retrovirus infecting domestic cats globally, which has also been documented in the North American puma (Puma concolor). The prevalent nature of FFV in domestic cats and its ability to infect wild felids, including puma, provides an ideal system to study cross-species transmission across trophic levels (positions in the food chain), and evolution of pathogens transmitted between individuals following direct contact. Here we present findings from an extensive molecular analysis of FFV in pumas, focused on two locations in Colorado, and in relation to FFV recovered from domestic cats in this and previous studies. Prevalence of FFV in puma was high across the two regions, ∼77 per cent (urban interface site) and ∼48 per cent (rural site). Comparison of FFV from pumas living across three states; Colorado, Florida, and California, indicates FFV is widely distributed across North America. FFV isolated from domestic cats and pumas was not distinguishable at the host level, with FFV sequences sharing >93 per cent nucleotide similarity. Phylogenetic, Bayesian, and recombination analyses of FFV across the two species supports frequent cross-species spillover from domestic cat to puma during the last century, as well as frequent puma-to-puma intraspecific transmission in Colorado, USA. Two FFV variants, distinguished by significant difference in the surface unit of the envelope protein, were commonly found in both hosts. This trait is also shared by simian foamy virus and may represent variation in cell tropism or a unique immune evasion mechanism. This study elucidates evolutionary and cross-species transmission dynamics of a highly prevalent multi-host adapted virus, a system which can further be applied to model spillover and transmission of pathogenic viruses resulting in widespread infection in the new host.
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Affiliation(s)
- Simona Kraberger
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
- The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life sciences, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85281, USA
| | - Nicholas M Fountain-Jones
- Department of Veterinary Population Medicine, University of Minnesota, 1365 Gortner Ave, Falcon Heights, St Paul, MN 55108, USA
| | - Roderick B Gagne
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Jennifer Malmberg
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Nicholas G Dannemiller
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Ken Logan
- Colorado Parks and Wildlife, 317 W Prospect Rd, Fort Collins, CO 80526, USA
| | - Mat Alldredge
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, 1474 Campus Delivery Fort Collins, CO 80523, USA
| | - Arvind Varsani
- The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life sciences, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85281, USA
- Structural Biology Research Unit, Department of Clinical Laboratory Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
| | - Kevin R Crooks
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, 1474 Campus Delivery Fort Collins, CO 80523, USA
| | - Meggan Craft
- Department of Veterinary Population Medicine, University of Minnesota, 1365 Gortner Ave, Falcon Heights, St Paul, MN 55108, USA
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia
| | - Sue VandeWoude
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
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Kechejian S, Dannemiller N, Kraberger S, Ledesma Feliciano C, Löchelt M, Carver S, VandeWoude S. Feline foamy virus seroprevalence and demographic risk factors in stray domestic cat populations in Colorado, Southern California and Florida, USA. JFMS Open Rep 2019; 5:2055116919873736. [PMID: 31555460 PMCID: PMC6747863 DOI: 10.1177/2055116919873736] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Objectives Our study aim was to document the seroprevalence and associated risk factors of feline foamy virus (FFV) infection in domestic cat populations presented to animal shelters located in Southern California, Colorado and Florida, USA. Methods We used a glutathione S-transferase capture ELISA targeting the FFV Gag antigen to screen domestic cat serum collected from cats with unknown owners at eight different animal shelters from Colorado (n = 105, three shelters), Southern California (n = 172, three shelters) and Florida (n = 31, two shelters). χ2 statistics determined location effect on seroprevalence. Bayesian generalized linear models were used to explore age and sex as potential risk factors for infection. Results FFV seroprevalence was 64.0% across all locations. Seroprevalence by location was as follows: Southern California 75.0%, Colorado 52.4% and Florida 41.9%, with Southern California’s seroprevalence being significantly higher. Age had a significant effect on model fit for all locations, with adults having a higher probability of being infected. In Colorado, sex also had a significant effect on model fit, with males having a higher probability of being infected. Conclusions and relevance We have documented that FFV is extremely common in stray domestic cat populations across varied geographic and ecological niches throughout the USA. Adult cats are at a higher FFV infection risk than young cats. FFV has been associated with a higher risk of other retroviral infections and has been implicated in several chronic diseases of cats. Additional epidemiological and clinical studies are warranted to investigate the potential impacts of FFV on domestic cat health.
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Affiliation(s)
- Sarah Kechejian
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Nick Dannemiller
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Simona Kraberger
- The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Carmen Ledesma Feliciano
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Martin Löchelt
- Department of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum Heidelberg, DKFZ), Heidelberg, Germany
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Sandy Bay, Tasmania, Australia
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
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Ledesma-Feliciano C, Troyer RM, Zheng X, Miller C, Cianciolo R, Bordicchia M, Dannemiller N, Gagne R, Beatty J, Quimby J, Löchelt M, VandeWoude S. Feline Foamy Virus Infection: Characterization of Experimental Infection and Prevalence of Natural Infection in Domestic Cats with and without Chronic Kidney Disease. Viruses 2019; 11:E662. [PMID: 31330990 PMCID: PMC6669521 DOI: 10.3390/v11070662] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/11/2019] [Accepted: 07/13/2019] [Indexed: 12/22/2022] Open
Abstract
Foamy viruses (FVs) are globally prevalent retroviruses that establish apparently apathogenic lifelong infections. Feline FV (FFV) has been isolated from domestic cats with concurrent diseases, including urinary syndromes. We experimentally infected five cats with FFV to study viral kinetics and tropism, peripheral blood mononuclear cell (PBMC) phenotype, urinary parameters, and histopathology. A persistent infection of primarily lymphoid tropism was detected with no evidence of immunological or hematologic perturbations. One cat with a significant negative correlation between lymphocytes and PBMC proviral load displayed an expanded FFV tissue tropism. Significantly increased blood urea nitrogen and ultrastructural kidney changes were noted in all experimentally infected cats, though chemistry parameters were not outside of normal ranges. Histopathological changes were observed in the brain, large intestine, and other tissues. In order to determine if there is an association of FFV with Chronic Kidney Disease, we additionally screened 125 Australian pet cats with and without CKD for FFV infection and found that FFV is highly prevalent in older cats, particularly in males with CKD, though this difference was not statistically significant compared to controls. Acute FFV infection was clinically silent, and while some measures indicated mild changes, there was no overt association of FFV infection with renal disease.
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Affiliation(s)
- Carmen Ledesma-Feliciano
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA
| | - Ryan M Troyer
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
- Department of Microbiology and Immunology, University of Western Ontario, 1151 Richmond St., London, ON N6A 5C1, Canada
| | - Xin Zheng
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Craig Miller
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74075, USA
| | - Rachel Cianciolo
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Matteo Bordicchia
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW 2006, Australia
| | - Nicholas Dannemiller
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Roderick Gagne
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Julia Beatty
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW 2006, Australia
| | - Jessica Quimby
- Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
- Department of Veterinary Clinical Sciences, The Ohio State University Veterinary Medical Center, 601 Vernon Tharpe Street, Columbus, OH 43210, USA
| | - Martin Löchelt
- Department of Viral Transformation Mechanisms, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
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Kechejian SR, Dannemiller N, Kraberger S, Ledesma-Feliciano C, Malmberg J, Roelke Parker M, Cunningham M, McBride R, Riley SPD, Vickers WT, Logan K, Alldredge M, Crooks K, Löchelt M, Carver S, VandeWoude S. Feline Foamy Virus is Highly Prevalent in Free-Ranging Puma concolor from Colorado, Florida and Southern California. Viruses 2019; 11:E359. [PMID: 31010173 PMCID: PMC6521117 DOI: 10.3390/v11040359] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 12/21/2022] Open
Abstract
Feline foamy virus (FFV) is a retrovirus that has been detected in multiple feline species, including domestic cats (Felis catus) and pumas (Puma concolor). FFV results in persistent infection but is generally thought to be apathogenic. Sero-prevalence in domestic cat populations has been documented in several countries, but the extent of viral infections in nondomestic felids has not been reported. In this study, we screened sera from 348 individual pumas from Colorado, Southern California and Florida for FFV exposure by assessing sero-reactivity using an FFV anti-Gag ELISA. We documented a sero-prevalence of 78.6% across all sampled subpopulations, representing 69.1% in Southern California, 77.3% in Colorado, and 83.5% in Florida. Age was a significant risk factor for FFV infection when analyzing the combined populations. This high prevalence in geographically distinct populations reveals widespread exposure of puma to FFV and suggests efficient shedding and transmission in wild populations.
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Affiliation(s)
- Sarah R Kechejian
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
| | - Nick Dannemiller
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
| | - Simona Kraberger
- Biodesign Institute, Arizona State University, Tempe, AZ 85281, USA.
| | - Carmen Ledesma-Feliciano
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, 12700 E 19th Ave, Aurora, CO 80045, USA.
| | - Jennifer Malmberg
- Wyoming State Vet Lab, University of Wyoming, 1174 Snowy Range Road, Laramie, WY 82072, USA.
| | - Melody Roelke Parker
- Frederick National Laboratory of Cancer Research, Leidos Biomedical Research, Inc., Frederick, MD 21701, USA.
| | - Mark Cunningham
- Florida Fish and Wildlife Conservation Commission, 1105 SW Williston Road, Gainesville, FL 32601, USA.
| | - Roy McBride
- Rancher's Supply Inc., Alpine, TX 79830, USA.
| | - Seth P D Riley
- National Park Service, Santa Monica Mountains National Recreation Area, Thousand Oaks, CA 90265, USA.
| | - Winston T Vickers
- Karen C. Drayer Wildlife Health Center, University of California, Davis, CA 95616, USA.
| | - Ken Logan
- Wildlife Researcher Colorado Parks and Wildlife, 2300 S. Townsend Avenue, Montrose, CO 80203, USA.
| | - Mat Alldredge
- Colorado Division of Wildlife Office, Mammals Research, 317 W. Prospect Rd, For Collins, CO 80526, USA.
| | - Kevin Crooks
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University 115 Wagar, Fort Collins, CO 80523, USA.
| | - Martin Löchelt
- Department of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center, (Deutsches Krebsforschungszentrum Heidelberg, DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany.
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Sandy Bay, Tasmania 7005, Australia.
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
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11
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Feline Leukemia Virus (FeLV) Disease Outcomes in a Domestic Cat Breeding Colony: Relationship to Endogenous FeLV and Other Chronic Viral Infections. J Virol 2018; 92:JVI.00649-18. [PMID: 29976676 DOI: 10.1128/jvi.00649-18] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/26/2018] [Indexed: 01/15/2023] Open
Abstract
Exogenous feline leukemia virus (FeLV) is a feline gammaretrovirus that results in a variety of disease outcomes. Endogenous FeLV (enFeLV) is a replication-defective provirus found in species belonging to the Felis genus, which includes the domestic cat (Felis catus). There have been few studies examining interaction between enFeLV genotype and FeLV progression. We examined point-in-time enFeLV and FeLV viral loads, as well as occurrence of FeLV/enFeLV recombinants (FeLV-B), to determine factors relating to clinical disease in a closed breeding colony of cats during a natural infection of FeLV. Coinfections with feline foamy virus (FFV), feline gammaherpesvirus 1 (FcaGHV-1), and feline coronavirus (FCoV) were also documented and analyzed for impact on cat health and FeLV disease. Correlation analysis and structural equation modeling techniques were used to measure interactions among disease parameters. Progressive FeLV disease and FeLV-B presence were associated with higher FeLV proviral and plasma viral loads. Female cats were more likely to have progressive disease and FeLV-B. Conversely, enFeLV copy number was higher in male cats and negatively associated with progressive FeLV disease. Males were more likely to have abortive FeLV disease. FFV proviral load was found to correlate positively with higher FeLV proviral and plasma viral load, detection of FeLV-B, and FCoV status. Male cats were much more likely to be infected with FcaGHV-1 than female cats. This analysis provides insights into the interplay between endogenous and exogenous FeLV during naturally occurring disease and reveals striking variation in the infection patterns among four chronic viral infections of domestic cats.IMPORTANCE Endogenous retroviruses are harbored by many animals, and their interactions with exogenous retroviral infections have not been widely studied. Feline leukemia virus (FeLV) is a relevant model system to examine this question, as endogenous and exogenous forms of the virus exist. In this analysis of a large domestic cat breeding colony naturally infected with FeLV, we documented that enFeLV copy number was higher in males and inversely related to FeLV viral load and associated with better FeLV disease outcomes. Females had lower enFeLV copy numbers and were more likely to have progressive FeLV disease and FeLV-B subtypes. FFV viral load was correlated with FeLV progression. FFV, FcaGHV-1, and FeLV displayed markedly different patterns of infection with respect to host demographics. This investigation revealed complex coinfection outcomes and viral ecology of chronic infections in a closed population.
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Quimby JM, Borjesson DL. Mesenchymal stem cell therapy in cats: Current knowledge and future potential. J Feline Med Surg 2018; 20:208-216. [PMID: 29478398 PMCID: PMC10816289 DOI: 10.1177/1098612x18758590] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Practical relevance: Stem cell therapy is an innovative field of scientific investigation with tremendous potential for clinical application in veterinary medicine. Based on the known desirable immunomodulatory properties of mesenchymal stem cells, this therapy holds promise for the treatment of a variety of inflammatory diseases in cats. AIMS This review details our current understanding of feline stem cell biology and proposed mechanism of action. Studies performed in feline clinical trials for diseases including gingivostomatitis, chronic enteropathy, asthma and kidney disease are summarized, with the goal of providing an overview of the current status of this treatment modality and its potential for the future.
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Affiliation(s)
- Jessica M Quimby
- The Ohio State University, Department of Veterinary Clinical Sciences, Columbus, OH 43210, USA
| | - Dori L Borjesson
- University of California–Davis, Veterinary Institute for Regenerative Cures, and Department of Pathology, Microbiology and Immunology, Davis, CA 95616, USA
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Mühle M, Bleiholder A, Löchelt M, Denner J. Epitope Mapping of the Antibody Response Against the Envelope Proteins of the Feline Foamy Virus. Viral Immunol 2017; 30:388-395. [PMID: 28355125 DOI: 10.1089/vim.2016.0156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Foamy viruses (FV) are retroviruses that infect several species without pathological signs, but induce substantial antibody responses in the infected host. In the case of feline FV (FFV), antibodies against Gag, Bet, and Env have been used to indicate infection; however, it is unclear whether the response to specific epitopes correlates with immunity. Here, we investigated the epitope specificity of antibodies targeting the Env protein using peptide microarrays. Sera from naturally and experimentally FFV-infected cats and pumas and from rats immunized with FFV Env expression plasmids were analyzed. An immunodominant epitope was identified in the Env leader protein (Elp), and a strong reactivity to two epitope clusters in the transmembrane (TM) subunit of Env was observed. Moreover, a short stretch of residues in the C-terminal part of the surface (SU) protein was found to be significantly associated with FFV serotype FUV-mediated neutralization. Taken together, our results add a new level of detail on the B cell epitope repertoire induced during FFV infection. Furthermore, our results provide a basis for current attempts to modify FV vectors to express and present vaccine epitopes for the directed induction of humoral immunity.
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Affiliation(s)
| | - Anne Bleiholder
- 2 German Cancer Research Center , Research Program Infection, Inflammation and Cancer, Heidelberg, Germany
| | - Martin Löchelt
- 2 German Cancer Research Center , Research Program Infection, Inflammation and Cancer, Heidelberg, Germany
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Arzi B, Kol A, Murphy B, Walker NJ, Wood JA, Clark K, Verstraete FJM, Borjesson DL. Feline foamy virus adversely affects feline mesenchymal stem cell culture and expansion: implications for animal model development. Stem Cells Dev 2014; 24:814-23. [PMID: 25404388 DOI: 10.1089/scd.2014.0317] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mesenchymal stem cells (MSCs) are a promising therapeutic option for various immune-mediated and inflammatory disorders due to their potent immunomodulatory and trophic properties. Naturally occurring diseases in large animal species may serve as surrogate animal models of human disease, as they may better reflect the complex genetic, environmental, and physiologic variation present in outbred populations. We work with naturally occurring diseases in large animal species to better understand how MSCs work and to facilitate optimal translation of MSC-based therapies. We are investigating the use of MSC therapy for a chronic oral inflammatory disease in cats. During our efforts to expand fat-derived feline MSCs (fMSCs), we observed that∼50% of the cell lines developed giant foamy multinucleated cells in later passages. These morphologic alterations were associated with proliferation arrest. We hypothesized that the cytopathic effects were caused by infection with a retrovirus, feline foamy virus (FFV). Using transmission electron microscopy, polymerase chain reaction, and in vitro assays, we determined that syncytial cell formation and proliferation arrest in fMSCs were caused by FFV strains that were highly homologous to previously reported FFV strains. We determined that the antiretroviral drug, tenofovir, may be used to support ex vivo expansion and salvage of FFV-infected fMSC lines. MSC lines derived from specific pathogen-free cats do not appear to be infected with FFV and may be a source of allogeneic fMSCs for clinical application. FFV infection of fMSC lines may hinder large-scale expansion of autologous MSC for therapeutic use in feline patients.
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Affiliation(s)
- Boaz Arzi
- 1 Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California , Davis, Davis, California
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Mühle M, Hoffmann K, Löchelt M, Denner J. Immunisation with foamy virus Bet fusion proteins as novel strategy for HIV-1 epitope delivery. Immunol Res 2013; 56:61-72. [PMID: 23440699 DOI: 10.1007/s12026-013-8387-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The induction of 2F5- and 4E10-like antibodies broadly neutralising HIV-1 and targeting the membrane external proximal region (MPER) of the transmembrane envelope protein gp41 would be a major advancement for the development of a preventive HIV-1 vaccine, but successful attempts remain rare. Recent studies demonstrated that broadly reactive antibodies develop relatively late during infection and after intensive affinity maturation. Therefore, a prolonged antigen delivery might be beneficial to induce them. Replicating foamy viruses which are characterised by apathogenic but persistent infection could represent suitable carrier viruses for this purpose. In order to develop such a system, we modified the accessory foamy virus Bet protein to contain the MPER of gp41, or the MPER linked to the stabilising fusion peptide proximal region of gp41 and analysed here the antigenic and immunogenic properties of such hybrid proteins. The antigens, expressed and purified to homogeneity, were recognised by the monoclonal antibodies 2F5 and 4E10 with nanomolar affinities and induced high levels of antibodies specific to gp41 after immunisation of rats. The antisera also bound to virus particles attached to infected cells, and peptide-based epitope mapping showed that they recognised the 2F5 epitope. Although no HIV-1 neutralising activity was observed, the presented data demonstrate that using the foamy virus Bet for HIV-1 epitope delivery is successfully applicable. Together with the attractive potential for sustained antigen expression after transfer to replicating virus, these results should therefore provide a first basis for the development of chimeric foamy viruses as novel HIV-1 vaccine vectors.
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Affiliation(s)
- Michael Mühle
- Center for HIV and Retrovirology, Robert Koch Institute, Berlin, Germany
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Mühle M, Hoffmann K, Löchelt M, Denner J. Construction and characterisation of replicating foamy viral vectors expressing HIV-1 epitopes recognised by broadly neutralising antibodies. Antiviral Res 2013; 100:314-20. [PMID: 24055836 DOI: 10.1016/j.antiviral.2013.09.009] [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: 04/24/2013] [Revised: 08/26/2013] [Accepted: 09/10/2013] [Indexed: 10/26/2022]
Abstract
With the aim to develop a replicating vector system for the delivery of HIV-1 antigens on the basis of an apathogenic foamy virus we recently showed that immunisation with purified recombinant hybrid antigens composed of the feline foamy virus Bet protein and parts of the transmembrane envelope protein of HIV-1 induced antibodies with an epitope specificity identical to that of the broadly neutralising antibody 2F5 (Mühle et al., Immunol Res., 2013, 56:61-72). Here we set out to further improve the HIV-1 inserts consisting of the membrane proximal external region (MPER) and the fusion peptide proximal region (FPPR) by stepwise shortening distinct linker residues between both domains. In a subset of these antigens, enhanced recognition by 2F5 and 4E10 was observed, indicating that a specific positioning of FPPR and MPER domains is critical for improved antibody binding. Introduction of these optimised inserts as well as of the MPER domain alone into the feline foamy virus backbone was compatible with virus replication, giving viral titres similar to wild-type virus after extended passaging. Most importantly, expression of the HIV-1 transgenes in infected feline CRFK cells remained stable in three out of four constructs and was detectable after serial passages for several weeks. These data encourage further testing of these vectors in vivo, which may allow insights into the necessity of affinity maturation for the induction of broadly reactive HIV-1 antibodies.
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Affiliation(s)
- Michael Mühle
- Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany
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Kehl T, Tan J, Materniak M. Non-simian foamy viruses: molecular virology, tropism and prevalence and zoonotic/interspecies transmission. Viruses 2013; 5:2169-209. [PMID: 24064793 PMCID: PMC3798896 DOI: 10.3390/v5092169] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 09/04/2013] [Accepted: 09/05/2013] [Indexed: 12/27/2022] Open
Abstract
Within the field of retrovirus, our knowledge of foamy viruses (FV) is still limited. Their unique replication strategy and mechanism of viral persistency needs further research to gain understanding of the virus-host interactions, especially in the light of the recent findings suggesting their ancient origin and long co-evolution with their nonhuman hosts. Unquestionably, the most studied member is the primate/prototype foamy virus (PFV) which was originally isolated from a human (designated as human foamy virus, HFV), but later identified as chimpanzee origin; phylogenetic analysis clearly places it among other Old World primates. Additionally, the study of non-simian animal FVs can contribute to a deeper understanding of FV-host interactions and development of other animal models. The review aims at highlighting areas of special interest regarding the structure, biology, virus-host interactions and interspecies transmission potential of primate as well as non-primate foamy viruses for gaining new insights into FV biology.
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Affiliation(s)
- Timo Kehl
- German Cancer Research Center, INF242, Heidelberg 69120, Germany
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +49-6221-42-4935; Fax: +49-6221-42-4932
| | - Juan Tan
- College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China; E-Mail:
| | - Magdalena Materniak
- Department of Biochemistry, National Veterinary Research Institute, Partyzantow Ave. 57, Pulawy 24-100, Poland; E-Mail:
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Similar patterns of infection with bovine foamy virus in experimentally inoculated calves and sheep. J Virol 2013; 87:3516-25. [PMID: 23325680 DOI: 10.1128/jvi.02447-12] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Foamy viruses (FVs) are the least known retroviruses commonly found in primates, cats, horses, and cattle. Although FVs are considered apathogenic, simian and feline FVs have been shown to be associated with some transient health abnormalities in animal models. Currently, data regarding the course of infection with bovine FV (BFV) are not available. In this study, we conducted experimental infections of natural (cattle) and heterologous (sheep) hosts with the BFV(100) isolate and monitored infection patterns in both hosts during the early phase postinoculation as well as after long-term infection. Four calves and six sheep inoculated with BFV(100) showed no signs of pathology but developed persistent infection, as confirmed by virus rescue, consistent detection of BFV-specific antibodies, and presence of viral DNA. In both hosts, antibodies against BFV Gag and Bet appeared early after infection and persisted at high and stable levels while seroreactivity toward Env was consistently detectable only in BFV-infected sheep. Interestingly, the BFV proviral DNA load was highest in lung, spleen, and liver and moderate in leukocytes, while salivary glands contained either low or undetectable DNA loads in calves or sheep, respectively. Additionally, comparison of partial BFV sequences from inoculum and infected animals demonstrated very limited changes after long-term infection in the heterologous host, clearly less than those found in BFV field isolates. The persistence of BFV infection in both hosts suggests full replication competence of the BFV(100) isolate with no requirement of genetic adaptation for productive replication in the authentic and even in a heterologous host.
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Denner J. Immunising with the transmembrane envelope proteins of different retroviruses including HIV-1: a comparative study. Hum Vaccin Immunother 2012; 9:462-70. [PMID: 23249763 DOI: 10.4161/hv.23221] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The induction of neutralizing antibodies is a promising way to prevent retrovirus infections. Neutralizing antibodies are mainly directed against the envelope proteins, which consist of two molecules, the surface envelope (SU) protein and the transmembrane envelope (TM) protein. Antibodies broadly neutralizing the human immunodeficiencvy virus-1 (HIV-1) and binding to the TM protein gp41 of the virus have been isolated from infected individuals. Their epitopes are located in the membrane proximal external region (MPER). Since there are difficulties to induce such neutralizing antibodies as basis for an effective AIDS vaccine, we performed a comparative analysis immunising with the TM proteins of different viruses from the family Retroviridae. Both subfamilies, the Orthoretrovirinae and the Spumaretrovirinae were included. In this study, the TM proteins of three gammaretroviruses including (1) the porcine endogenous retrovirus (PERV), (2) the Koala retrovirus (KoRV), (3) the feline leukemia virus (FeLV), of two lentiviruses, HIV-1, HIV-2, and of two spumaviruses, the feline foamy virus (FFV) and the primate foamy virus (PFV) were used for immunisation. Whereas in all immunisation studies binding antibodies were induced, neutralizing antibodies were only found in the case of the gammaretroviruses. The induced antibodies were directed against the MPER and the fusion peptide proximal region (FPPR) of their TM proteins; however only the antibodies against the MPER were neutralizing. Most importantly, the epitopes in the MPER were localized in the same position as the epitopes of the antibodies broadly neutralizing HIV-1 in the TM protein gp41 of HIV-1, indicating that the MPER is an effective target for the neutralization of retroviruses.
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Mühle M, Löchelt M, Denner J. Optimisation of expression and purification of the feline and primate foamy virus transmembrane envelope proteins using a 96 deep well screen. Protein Expr Purif 2011; 81:96-105. [PMID: 21964437 DOI: 10.1016/j.pep.2011.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 09/04/2011] [Accepted: 09/13/2011] [Indexed: 12/21/2022]
Abstract
The production of recombinant transmembrane proteins is due to their biochemical properties often troublesome and time consuming. Here the prokaryotic expression and purification of the transmembrane envelope proteins of the feline and primate foamy viruses using a screening assay for optimisation of expression in 96 deep well plates is described. Testing simultaneously various bacterial strains, media, temperatures, inducer concentrations and different transformants, conditions for an about twentyfold increased production were quickly determined. These small scale test conditions could be easily scaled up, allowing purification of milligram amounts of recombinant protein. Proteins with a purity of about 95% were produced using a new purification protocol, they were characterised by gel filtration and circular dichroism and successfully applied in immunological assays screening for foamy virus infection and in immunisation studies. Compared to the previously described protocol (M. Mühle, A. Bleiholder, S. Kolb, J. Hübner, M. Löchelt, J. Denner, Immunological properties of the transmembrane envelope protein of the feline foamy virus and its use for serological screening, Virology 412 (2011) 333-340), proteins with similar characteristics but about thirtyfold increased yields were obtained. The screening and production method presented here can also be applied for the production of transmembrane envelope proteins of other retroviruses, including HIV-1.
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Affiliation(s)
- Michael Mühle
- Robert Koch Institute, Nordufer 20, Berlin 13353, Germany
| | - Martin Löchelt
- German Institute for Cancer Research, Im Neuenheimer Feld 242, Heidelberg 69120, Germany
| | - Joachim Denner
- Robert Koch Institute, Nordufer 20, Berlin 13353, Germany.
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