Progress 10/01/23 to 09/30/24
Outputs
PROGRESS REPORT Objectives (from AD-416): Objective 1: Characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. Sub-objective 1.1: Detect and classify leptospires circulating in dairy cows. Sub-objective 1.2: Characterization of recent isolates of pathogenic leptospires. Sub-objective 1.3: Enhanced bacterin intervention strategies. Objective 2: Characterize the pathogenesis of DD for the development of more effective intervention strategies. Sub-objective 2.1: Characterization of Treponema and other pathogens in DD. Sub-objective 2.2: Development of host immune response to antigens from DD lesions. Sub-objective 2.3: Development of effective intervention strategies for DD. Approach (from AD-416): Leptospirosis and digital dermatitis (DD) are two different diseases caused by two separate groups of bacteria in the Phylum Spirochaetes that have substantial impact on livestock production. Multiple serovars of Leptospira interrogans are the leading cause of acute lethal leptospirosis in humans and domestic animals while serovar Hardjo of L. borgpetersenii is the leading cause of bovine disease, causing reproductive failure and persistent shedding via urine to maintain disease transmission. Current bovine bacterin vaccines are limited in efficacy. To improve on this, Objective 1 will characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. It is first necessary to identify those species and serovars of Leptospira currently circulating in animal populations, as described in subobjective 1.1. Given the importance of L. borgpetersenii to animal disease, subobjective 1.2. will include comparative genomics and proteomics of multiple serovars within Leptospira borgpetersenii to identify conserved pathogenic mechanisms of infection and candidate vaccinogens as potential recombinant subunit vaccines. We hypothesize that efficacy of bacterins can be further improved to provide heterologous protection using growth media that more closely emulates that encountered during host infection, as proposed in subobjective 1.3. Unlike leptospirosis, DD is an infectious polymicrobial skin infection in which Treponema species are found at the invading edge of the lesions. Causing painful ulcerative proliferative and necrotizing lesions on the skin at or near the hooves, DD is a significant cause of lameness in both dairy and feedlot cattle. Aside from lameness being a significant animal welfare issues, DD leads to decreased production, higher treatment costs and premature culling. Objective 2 will characterize the pathogenesis of DD for the development of more effective intervention strategies. Since the etiology of DD is not fully characterized, subobjective 2.1 will use bacterial 16S rRNA gene sequencing to characterize bacterial community of early DD lesions as induced in a sheep model, compare the sheep model to naturally infected bovine DD lesions in order to determine a core consortium of Treponema and other pathogens present. After obtaining isolates representing this core consortium, a defined mixture of Treponema species and other bacterial pathogens will be used to induce lesions in the sheep model. Subobjective 2.2. will then characterize the bovine innate immune responses to Treponema, and how that may affect lesion healing. Since current mitigation strategies use heavy metal, formalin-containing footbaths or topical antibiotics, subobjective 2.3. will evaluate novel alternative antimicrobial compounds for topical treatment of DD lesions. Understanding pathogenic mechanisms used by Spirochetes, specific species causing disease and host-pathogen interactions, are critical for the development of efficacious diagnostics, vaccines, and therapeutics for control of infection in domestic livestock. To address Objective 1, studies were conducted to identify and characterize Leptospira circulating in livestock and the environment. Leptospira were cultured from Iowa water sources, dairy cows in California, bulls in Colorado, bulls in Texas and horses in Kentucky. Samples included urine and semen and viable leptospira were detected in frozen bovine semen. As vaccine protection is generally limited to that leptospira serovar, understanding circulating serotypes and strains is critical for successful disease intervention strategies because it is likely that current bacterin may not contain some key serotypes and strains. Novel approaches have also been developed to genetically manipulate pathogenic Leptospira to identify virulence factors that may contribute to development of a cross protective vaccine. To address Objective 2, long-acting vaccine delivery platforms using recombinant proteins from Haemonchus contortus were evaluated in sheep. This work demonstrated the utility of single dose vaccines in inducing sustained immunity in livestock as a model for characterizing responses of sheep to subunit vaccines against other pathogens, like Treponema. The ability of novel biocides to eliminate bacterial pathogens was obtained, specifically demonstrating hydrazone containing biocides are bactericidal on mastitis pathogens and as surface treatments for eliminating Treponemes that cause digital dermatitis. These biocides offer producers environmentally safe alternatives to antibiotics. National distribution and prevalence of digital dermatitis and ovine foot-rot is being characterized using samples obtained in the 2024 NAHMS (National Animal Health Monitoring Service). Artificial Intelligence (AI)/Machine Learning (ML) Machine learning was used in in this project in FY24 to analyze microbiome data. The analysis and results are reported in manuscript: ⿿Wilson-Welder JH, Han S, Bayles DO, Alt DP, Kanipe C, Garrison K, Mansfield KG, Olsen SC. Correlation of lesion severity with bacterial changes in Treponeme-Associated Hoof Disease from free-roaming wild elk (Cervus canadensis). Anim Microbiome. 2024 Apr 22;6(1):20. doi: 10.1186/ s42523-024-00304-9. ACCOMPLISHMENTS 01 New species of Leptospira in Iowa water sources. In a collaborative project with scientists at the National Veterinary Service Laboratory, ARS scientists in Ames, Iowa surveyed water sources in Iowa for the presence of Leptospira. Water samples were tested by culture and PCR for the presence of environmental and pathogenic leptospirosis species. Data demonstrated that 78% of samples were culture positive for Leptospira with 9.5% containing pathogenic Leptospira. Whole genome sequencing of isolates identified three novel nonpathogenic species and two novel pathogenic species. This study emphasizes the diversity of Leptospira circulating in Iowa water sources, facilitates development of improved diagnostics to detect Leptospira, and emphasizes the role of water in the transmission of leptospirosis to humans and livestock. This work will be of interest to livestock owners, regulatory and public health personnel, and researchers with interest in leptospirosis. 02 Horses are reservoir hosts of Leptospira. In collaborative studies with scientists at the University of Kentucky, ARS scientists in Ames, Iowa demonstrated that mares can be reservoir hosts of animal leptospirosis. Results demonstrated asymptomatic mares actively excrete different species and serovars of Leptospira. Isolates included Leptospira interrogans serovar Copenhageni and L. kirschneri serovar Rushan, an isolate not previously identified in the U.S. The lipopolysaccharide (LPS) of L. kirschneri serovar Rushan differs from the LPS of serovars included in commercial bacterin vaccines suggesting that current vaccines may not protect against this serovar. The unique structure of its LPS also suggests it may not be detected by current leptospirosis diagnostic assays used in the U.S. This work will be of interest to livestock owners, regulatory personnel, and researchers with interest in leptospirosis. 03 Proteomic profiles of L. borgpetersenii serovar Hardjo a primary cause of leptospirosis in cattle. Leptospirosis is a zoonotic disease that causes reproductive losses and infertility in cattle with L. borgpetersenii serovar Hardjo being the most prevalent isolate associated with infections in cattle. Pathogenic species of Leptospira are known to modify antigen expression when exposed to different environmental cues, including temperature, during host infection. ARS scientists in Ames, Iowa, characterized differences in expression of more than 3,000 proteins of two serovar Hardjo strains after incubation at two temperatures (29 and 37 C). Proteins expressed at high levels by serovar Hardjo at body temperature were identified.for consideration in developing improved bacterin vaccines. This work will be of interest to commercial vaccine producers, stakeholders, regulatory personnel, and researchers with interest in leptospirosis and leptospirosis vaccines.
Impacts
(N/A)
Publications
- Shiel, R.E., Nolan, C.M., Nally, J.E., Refsal, K.R., Mooney, C.T. 2021. Qualitative and semiquantitative assessment of thyroid hormone binding proteins in greyhounds and other dog breeds. Domestic Animal Endocrinology. 76:1-8. https://doi.org/10.1016/j.domaniend.2021.106623.
- Putz, E.J., Fernandes, L.G., Bayles, D.O., Lippolis, J.D., Nally, J.E. 2022. Proteomic dataset comparing strains of Leptospira borgpetersenii serovar Hardjo cultured at different temperatures. Data in Brief. 45. https://doi.org/10.1016/j.dib.2022.108713.
- Anderson, T., Hamond, C., Haluch, A., Toot, K., Nally, J.E., LeCount, K., Schlater, L.K. 2023. Animals exposed to Leptospira Serogroups not included in bacterins in the United States and Puerto Rico. Tropical Medicine and Infectious Disease. 8(3). https://doi.org/10.3390/tropicalmed8030183.
- Stone, N.E., McDonough, R.F., Hamond, C., LeCount, K., Busch, J.D., Dirsmith, K.L., Rivera-Garcia, S., Soltero, F., Arnold, L.M., Weiner, Z., Galloway, R.L., Schlater, L.K., Nally, J.E., Sahl, J.W., Wagner, D.M. 2023. DNA capture and enrichment: a culture-independent approach for characterizing the genomic diversity of pathogenic leptospira species. Microorganisms. 11(5). https://doi.org/10.3390/microorganisms11051282.
- Hamond, C., Adam, E., Stone, N.E., LeCount, K., Anderson, T., Putz, E.J., Camp, P., Hicks, J., Stuber, T., Van Der Linden, H., Bayles, D.O., Sahl, J. W., Schlater, L.K., Wagner, D.M., Nally, J.E. 2024. Identification of equine mares as reservoir hosts for pathogenic species of Leptospira. Frontiers in Veterinary Science. 11. https://doi.org/10.3389/fvets.2024. 1346713.
- Hamond, C., Dirsmith, K.L., LeCount, K., Soltero, F.V., Rivera-Garcia, S., Camp, P., Anderson, T., Hicks, J.A., Galloway, R., Sutherland, G., Schafer, I.J., Goris, M.G., Van Der Linden, H., Stuber, T., Bayles, D.O., Schlater, L., Nally, J.E. 2022. Leptospira borgpetersenii serovar Hardjo and Leptospira santarosai serogroup Pyrogenes isolated from bovine dairy herds in Puerto Rico. Frontiers in Veterinary Science. 9. https://doi.org/10. 3389/fvets.2022.1025282.
- Canales, N., Bustamante, H., Wilson-Welder, J.H., Thomas, C., Ramirez, E., Salgado, M. 2022. First molecular confirmation of Treponema spp. in lesions consistent with digital dermatitis in Chilean dairy cattle. Pathogens. https://doi.org/10.3390/pathogens11050510.
- Wilson-Welder, J.H., Han, S., Bayles, D., Alt, D.P., Kanipe, C.R., Garrison, K., Mansfield, K., Olsen, S.C. 2024. Correlation of lesion severity with bacterial changes in Treponeme-Associated Hoof Disease from free-roaming wild elk (Cervus canadensis). Animal Microbiome. https://doi. org/10.1186/s42523-024-00304-9.
- Putz, E.J., Fernandes, L.G., Sarlo Davila, K.M., Whitelegge, J., Lippolis, J.D., Nally, J.E. 2024. Proteomic profiles of Leptospira borgpetersenii serovar Hardjo strains JB197 and HB203 cultured at different temperatures. Journal of Proteomics. 295. https://doi.org/10.1016/j.jprot.2024.105106.
- LeCount, K., Fox, K., Anderson, T., Bayles, D.O., Stuber, T., Hicks, J., Schlater, L.K., Nally, J.E. 2023. Isolation of Leptospira kirschneri serovar Grippotyphosa from a red panda (Ailurus fulgens) after antimicrobial therapy: case report. Frontiers in Veterinary Science. 9. https://doi.org/10.3389/fvets.2022.1064147.
- Hamond, C., LeCount, K., Anderson, T., Putz, E.J., Stuber, T., Hicks, J., Camp, P., Van Der Linden, H., Bayles, D.O., Schlater, L.K., Nally, J.E. 2024. Isolation and characterization of saprophytic and pathogenic strains of Leptospira from water sources in the Midwestern United States. Frontiers in Water. 6. https://doi.org/10.3389/frwa.2024.1278088.
- Hamond, C., LeCount, K., Browne, A., Anderson, T., Stuber, T., Hicks, J., Camp, P., Fernandes, L.G., Van Der Linden, H., Goris, M.G., Bayles, D.O., Schlater, L.K., Nally, J.E. 2023. Concurrent colonization of rodent kidneys with multiple species and serogroups of pathogenic Leptospira. Applied and Environmental Microbiology. 89(10). https://doi.org/10.1128/ aem.01204-23.
- Lynn, L.E., Scholes, R.C., Kim, J., Wilson-Welder, J.H., Orts, W.J., Hart- Cooper, W.M. 2024. Antimicrobial, preservative, and hazard assessments from eight chemical classes. ACS Omega. 9(16):17869⿿17877. https://doi.org/ 10.1021/acsomega.3c08672.
|
Progress 10/01/22 to 09/30/23
Outputs
PROGRESS REPORT Objectives (from AD-416): Objective 1: Characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. Sub-objective 1.1: Detect and classify leptospires circulating in dairy cows. Sub-objective 1.2: Characterization of recent isolates of pathogenic leptospires. Sub-objective 1.3: Enhanced bacterin intervention strategies. Objective 2: Characterize the pathogenesis of DD for the development of more effective intervention strategies. Sub-objective 2.1: Characterization of Treponema and other pathogens in DD. Sub-objective 2.2: Development of host immune response to antigens from DD lesions. Sub-objective 2.3: Development of effective intervention strategies for DD. Approach (from AD-416): Leptospirosis and digital dermatitis (DD) are two different diseases caused by two separate groups of bacteria in the Phylum Spirochaetes that have substantial impact on livestock production. Multiple serovars of Leptospira interrogans are the leading cause of acute lethal leptospirosis in humans and domestic animals while serovar Hardjo of L. borgpetersenii is the leading cause of bovine disease, causing reproductive failure and persistent shedding via urine to maintain disease transmission. Current bovine bacterin vaccines are limited in efficacy. To improve on this, Objective 1 will characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. It is first necessary to identify those species and serovars of Leptospira currently circulating in animal populations, as described in subobjective 1.1. Given the importance of L. borgpetersenii to animal disease, subobjective 1.2. will include comparative genomics and proteomics of multiple serovars within Leptospira borgpetersenii to identify conserved pathogenic mechanisms of infection and candidate vaccinogens as potential recombinant subunit vaccines. We hypothesize that efficacy of bacterins can be further improved to provide heterologous protection using growth media that more closely emulates that encountered during host infection, as proposed in subobjective 1.3. Unlike leptospirosis, DD is an infectious polymicrobial skin infection in which Treponema species are found at the invading edge of the lesions. Causing painful ulcerative proliferative and necrotizing lesions on the skin at or near the hooves, DD is a significant cause of lameness in both dairy and feedlot cattle. Aside from lameness being a significant animal welfare issues, DD leads to decreased production, higher treatment costs and premature culling. Objective 2 will characterize the pathogenesis of DD for the development of more effective intervention strategies. Since the etiology of DD is not fully characterized, subobjective 2.1 will use bacterial 16S rRNA gene sequencing to characterize bacterial community of early DD lesions as induced in a sheep model, compare the sheep model to naturally infected bovine DD lesions in order to determine a core consortium of Treponema and other pathogens present. After obtaining isolates representing this core consortium, a defined mixture of Treponema species and other bacterial pathogens will be used to induce lesions in the sheep model. Subobjective 2.2. will then characterize the bovine innate immune responses to Treponema, and how that may affect lesion healing. Since current mitigation strategies use heavy metal, formalin-containing footbaths or topical antibiotics, subobjective 2.3. will evaluate novel alternative antimicrobial compounds for topical treatment of DD lesions. Understanding pathogenic mechanisms used by Spirochetes, specific species causing disease and host-pathogen interactions, are critical for the development of efficacious diagnostics, vaccines, and therapeutics for control of infection in domestic livestock. To address Objective 1, studies were conducted characterizing circulating Leptospira in livestock populations. This included recovery pf Leptospira circulating in dairy cattle in CA and spirochete bacteria within polymerase chain reaction (PCR)-positive bovine semen. Recovered isolates were characterized by genome sequencing and serotyping to determine the specific Leptospira serovar. As vaccine protection is generally limited by serovar, understanding circulating serotypes and strains is critical for development of successful disease intervention strategies. As L. borgpetersenii is the most prevalent species of Leptospira associated with animal infections, the genomes of multiple serovars within this Leptospira species were sequenced, and their respective proteomes characterized to identify conserved and differentially expressed proteins that could be used in novel vaccines or diagnostics assays. In studies addressing Objective 2, archived digital dermatitis (DD) lesion material was expanded in vivo using a sheep model of infection and bacterial populations characterized. Analysis of samples collected at various timepoints post-infection demonstrated that the most predominant bacterial phyla within lesions were Firmicutes, Bacteroidota and Spirochaetae. In vitro bacterial culture was conducted to obtain isolates within these phyla to determine individual bacterial species, in addition to recovering isolates of Mycoplasma and minor phyla, which are hypothesized to contribute to DD lesion development. This work allows characterization of bacterial populations which induce lesions of DD, thereby enabling development of intervention strategies. Environmentally safe chemical compounds which inhibit or kill harmful bacteria (biocides) were evaluated for their inactivation properties on bacterial isolates. Based on these studies, a topical balm containing a hydrazone-based biocide was developed and tested under in vivo conditions on DD lesions. The topical treatment was similar in efficacy to an antibiotic containing paste in treating DD lesions under experimental conditions. Through an MTRA with a commercial company, further studies are being conducted with the topical biocide treatment under field conditions. Artificial Intelligence (AI)/Machine Learning (ML) Machine learning was not used in the project in FY23. ACCOMPLISHMENTS 01 Novel assay for Leptospira identification. Novel assay to determine genomes of Leptospira directly from field samples. In collaboration with academic scientists, ARS scientists in Ames, Iowa, validated a culture-independent DNA capture and enrichment system for characterizing Leptospira genomic data from field samples. The assay greatly increases recovery of Leptospira DNA from field samples and facilitates robust species identification and high-resolution genotyping. Sequence data of recovered DNA is similar in quality to data from in vitro cultured isolates. Implementation of this DNA capture and enrichment assay improves identification of Leptospira in unculturable samples and expands understanding of Leptospira populations and genomic diversity. The assay will improve epidemiologic knowledge of Leptospira distribution, facilitate development of improved diagnostics and vaccines, and will be of interest to diagnostic personnel, scientists, and livestock producers. The assay has already been used to demonstrate that U.S. cattle can be infected with more than one species of Leptospira concurrently. 02 Leptospira concurrent infections. Confirmation of Leptospira concurrent infections to inform potential transmission of the disease in animals. It has been hypothesized that domestic and wildlife animal reservoirs of leptospirosis can be co-infected and shed multiple species of Leptospira concurrently. This would impact the development of intervention strategies. However, definitive microbiologic evidence of this phenomena in any species was lacking. ARS scientists in Ames, Iowa, developed a novel culture strategy that was applied to samples from rodents suspected of being co-infected with multiple Leptospira species. Results definitively prove the hypothesis that reservoir hosts can be colonized with more than one species of Leptospira concurrently. Demonstration of co-infection of Leptospira in a reservoir host has implications for understanding the epidemiology and transmission of spirochete disease in human and animal populations, and will be of interest to producers, veterinarians, and public health professionals. 03 Identification of new Leptospira species. Leptospirosis is a zoonotic disease with multiple serovars that can cause chronic disease in human and animal reservoir hosts. Recovery of Leptospira from environmental samples is difficult but may allow identification of new species. ARS scientists in Ames, Iowa, isolated two novel spirochetes (designated strains LGVF01 and LGVF02) from soil samples in San Juan, Puerto Rico using microbiological techniques and confirmed using various tests. Genome sequence analysis indicated that both strains are members of a novel species within the pathogenic (P1) clade of the Leptospira genus. Although highly homologous (99.2% nucleotide identity), the two strains had much greater nucleotide differences when compared to previously described leptospiral species (<93.2% nucleotide identity). Serotyping suggests strain LGVF02 represents a new novel Leptospira serovar. Collectively, these two novel strains represent a new species of pathogenic Leptospira for which the name Leptospira sanjuanensis sp. nov is proposed. This work will be of interest to producers, veterinarians, and public health professionals.
Impacts
(N/A)
Publications
- Sykes, J.E., Gamage, C.D., Haake, D.A., Nally, J.E. 2022. Understanding leptospirosis: application of state-of-the-art molecular typing tools with a One Health lens. American Journal of Veterinary Research. 83(10). https:/ /doi.org/10.2460/ajvr.22.06.0104.
- Fernandes, L.G., Stone, N.E., Roe, C.C., Goris, M.G., Van Der Linden, H., Sahl, J.W., Wagner, D.E., Nally, J.E. 2022. Leptospira sanjuanensis sp. nov., a pathogenic species of the genus Leptospira isolated from soil in Puerto Rico. International Journal of Systematic and Evolutionary Microbiology. 72(10). eArticle 5560. https://doi.org/10.1099/ijsem.0. 005560.
- Sykes, J.E., Haake, D.A., Gamage, C.D., Mills, W., Nally, J.E. 2022. A Global One Health Perspective on Leptospirosis in Humans and Animals. Journal of the American Veterinary Medical Association. 260(13). p. 1589- 1596. https://doi.org/10.2460/javma.22.06.0258.
|
Progress 10/01/21 to 09/30/22
Outputs
PROGRESS REPORT Objectives (from AD-416): Objective 1: Characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. Sub-objective 1.1: Detect and classify leptospires circulating in dairy cows. Sub-objective 1.2: Characterization of recent isolates of pathogenic leptospires. Sub-objective 1.3: Enhanced bacterin intervention strategies. Objective 2: Characterize the pathogenesis of DD for the development of more effective intervention strategies. Sub-objective 2.1: Characterization of Treponema and other pathogens in DD. Sub-objective 2.2: Development of host immune response to antigens from DD lesions. Sub-objective 2.3: Development of effective intervention strategies for DD. Approach (from AD-416): Leptospirosis and digital dermatitis (DD) are two different diseases caused by two separate groups of bacteria in the Phylum Spirochaetes that have substantial impact on livestock production. Multiple serovars of Leptospira interrogans are the leading cause of acute lethal leptospirosis in humans and domestic animals while serovar Hardjo of L. borgpetersenii is the leading cause of bovine disease, causing reproductive failure and persistent shedding via urine to maintain disease transmission. Current bovine bacterin vaccines are limited in efficacy. To improve on this, Objective 1 will characterize leptospires circulating in dairy cows to advance the development of efficacious intervention strategies. It is first necessary to identify those species and serovars of Leptospira currently circulating in animal populations, as described in subobjective 1.1. Given the importance of L. borgpetersenii to animal disease, subobjective 1.2. will include comparative genomics and proteomics of multiple serovars within Leptospira borgpetersenii to identify conserved pathogenic mechanisms of infection and candidate vaccinogens as potential recombinant subunit vaccines. We hypothesize that efficacy of bacterins can be further improved to provide heterologous protection using growth media that more closely emulates that encountered during host infection, as proposed in subobjective 1.3. Unlike leptospirosis, DD is an infectious polymicrobial skin infection in which Treponema species are found at the invading edge of the lesions. Causing painful ulcerative proliferative and necrotizing lesions on the skin at or near the hooves, DD is a significant cause of lameness in both dairy and feedlot cattle. Aside from lameness being a significant animal welfare issues, DD leads to decreased production, higher treatment costs and premature culling. Objective 2 will characterize the pathogenesis of DD for the development of more effective intervention strategies. Since the etiology of DD is not fully characterized, subobjective 2.1 will use bacterial 16S rRNA gene sequencing to characterize bacterial community of early DD lesions as induced in a sheep model, compare the sheep model to naturally infected bovine DD lesions in order to determine a core consortium of Treponema and other pathogens present. After obtaining isolates representing this core consortium, a defined mixture of Treponema species and other bacterial pathogens will be used to induce lesions in the sheep model. Subobjective 2.2. will then characterize the bovine innate immune responses to Treponema, and how that may affect lesion healing. Since current mitigation strategies use heavy metal, formalin-containing footbaths or topical antibiotics, subobjective 2.3. will evaluate novel alternative antimicrobial compounds for topical treatment of DD lesions. Understanding pathogenic mechanisms used by Spirochetes, specific species causing disease and host-pathogen interactions, are critical for the development of efficacious diagnostics, vaccines, and therapeutics for control of infection in domestic livestock. During FY2022, new species and serovars of Leptospira were isolated from dairy cows and bulls. Isolates are being characterized by genome sequencing and serotyping. As vaccine protection is generally limited by serotype, understanding circulating serotypes and strains is critical for disease intervention strategies. In a similar manner, research characterizing the microbiome of bacteria within digital dermatitis (DD) lesions in cattle and wild elk proceeded with the goal of elucidating the pathogenesis of this polymicrobial disease. Specifically, research studies were focused on characterizing the influences of stage of development and duration of persistence on the microbiome of DD lesions. A group of novel, environmentally-safe chemicals, biocides, were evaluated for their ability to act as disinfectants on anaerobic and aerobic bacteria including those associated with DD lesions. The effect of organic materials on the ability of biocides to function as disinfectants was also characterized. ACCOMPLISHMENTS 01 Protein expression by Leptospira. Proteins expressed by Leptospira at body temperatures may be candidates for effective vaccines. Leptospirosis is a zoonotic disease that causes reproductive losses and infertility in cattle with L. borgpetersenii serovar Hardjo being the most prevalent isolate associated with infections in cattle. Leptospira borgpetersenii serovar Hardjo can only be isolated and propagated at 29C. Since pathogenic species of Leptospira are known to modify antigen expression when exposed to different incubation temperatures, ARS scientists in Ames, Iowa, developed and used a new media to characterize protein expression of serovar Hardjo at temperatures encountered during host infection. Leptospira proteins were identified that had increased expression at body temperature that may be upregulated during in vivo infection. These proteins may be more immunogenic in vivo and therefore attractive targets for development of novel vaccines. This work will be of interest to stakeholders, regulatory personnel, and researchers with interest in leptospirosis and leptospirosis vaccines. 02 New Leptospira species and serovars identified in dairy cows. Leptospirosis is a disease that infects multiple species, including humans, that causes reproductive losses and infertility in dairy cattle. Vaccines against leptospirosis are only efficacious for the serotype(s) included in the vaccine. ARS scientists in Ames, Iowa, made the first isolation of L borgpetersenii serovar Tarassovi from a dairy cow in Minnesota, and the first isolation of L. santarosai serogroup Pyrogenes from a dairy cow in Puerto Rico. These isolations suggest a possibility that current commercial cattle vaccines may need modification to include these new serotypes. This work will be of interest to stakeholders, regulatory personnel, and researchers with interest in leptospirosis and leptospirosis vaccines. 03 Foamy macrophages in animal leptospirosis models. In the United States, Leptospira bacterin vaccines must satisfy codified regulations that require their evaluation in a hamster model of leptospirosis. ARS scientists in Ames, Iowa, observed a novel immune cell type that circulates in the blood of hamsters infected with leptospires. The novel immune cell type was consistent with lipid filled foamy macrophages (FM). This unique finding of circulating FM in the hamster model of leptospirosis suggests novel, unexplored, immune activated pathways that are induced by exposure to pathogenic Leptospira. This work will be of interest to stakeholders, regulatory personnel, and researchers with interest in leptospirosis and leptospirosis vaccines.
Impacts
(N/A)
Publications
- Putz, E.J., Sivasankaran, S.K., Fernandes, L.G., Brunelle, B.W., Lippolis, J.D., Alt, D.P., Bayles, D.O., Hornsby, R.L., Nally, J.E. 2021. Distinct transcriptional profiles of Leptospira borgpetersenii serovar Hardjo strains JB197 and HB203 cultured at different temperatures. PLOS Neglected Tropical Diseases. 15(4). Article e0009320. https://doi.org/10.1371/ journal.pntd.0009320.
- Cranford, H.M., Taylor, M., Browne, A., Alt, D.P., Anderson, T., Hammond, C., Hornsby, R.L., Lecount, K., Schlater, L., Stuber, T., Dewilde, L., Burke-France, V.J., Ellis, E.M., Nally, J.E., Bradford, B. 2021. Prevalence of Pathogenic Leptospira in Livestock in St. Croix, U.S. Virgin Islands. Tropical Medicine and Infectious Disease. 6(2), Article 85. https://doi.org/10.3390/tropicalmed6020085.
- Fernandes, L.G., Hornsby, R.L., Nascimento, A., Nally, J.E. 2021. Application of CRISPR interference (CRISPRi) for gene silencing in pathogenic species of Leptospira. The Journal of Visualized Experiments (JoVE). 174. Article e62631. https://doi.org/10.3791/62631.
- Nally, J.E., Hornsby, R.L., Alt, D.P. 2021. Antigen specific urinary immunoglobulin in reservoir hosts of leptospirosis. Veterinary Sciences. 8(9). Article 178. https://doi.org/10.3390/vetsci8090178.
- Cranford, H.M., Browne, A.S., Lecount, K., Anderson, T., Hamond, C., Schlater, L., Stuber, T., Burke-France, V.J., Taylor, M., Harrison, C.J., Matias, K.Y., Medley, A., Rossow, J., Wiese, N., Jankelunas, L., De Wilde, L., Mehalick, M., Blanchard, G.L., Garcia, K.R., Mckinley, A.S., Lombard, C.D., Valiulis, J., Bradford, B., Berentsen, A., Salzer, J.S., Galloway, R. , Schafer, I.J., Bisgard, K., Roth, J., Ellis, B.R., Ellis, E.M., Nally, J. E. 2021. Mongooses (Urva auropunctata) as reservoir hosts of Leptospira species in the United States Virgin Islands, 2019�2020. PLOS Neglected Tropical Diseases. 15(11). Article e0009859. https://doi.org/10.1371/ journal.pntd.0009859.
- Putz, E.J., Andreasen, C.B., Stasko, J.A., Fernandes, L.G., Palmer, M.V., Rauh, M.J., Nally, J.E. 2021. Circulating foamy macrophages in the Golden Syrian Hamster model of Leptospirosis. Journal of Comparative Pathology. 189(10):98-109. https://doi.org/10.1016/j.jcpa.2021.10.004.
- Hamond, C., Browne, A.S., Hornsby, R.L., Lecount, K., Anderson, T., Stuber, T., De Wilde, L.H., Cranford, H.M., Browne, S.K., Blanchard, G., Horner, D., Taylor, M.L., Evans, M., Roth, J., Bisgard, K., Salzer, J., Schafer, I. , Ellis, B., Alt, D.P., Schlater, L., Nally, J.E., Ellis, E.M. 2022. Assessing rodents as carriers of pathogenic leptospires in the U.S. Virgin Islands: the risk to animal and public health. Scientific Reports. 12. Article 1132. https://doi.org/10.1038/s41598-022-04846-3.
- Fernandes, L.G., Putz, E.J., Stasko, J.A., Lippolis, J.D., Nascimento, A.L. , Nally, J.E. 2022. Evaluation of LipL32 and LigA/LigB knockdown mutants in Leptospira interrogans Serovar Copenhageni: impacts to proteome and virulence. Frontiers in Microbiology. 12. Article 799012. https://doi.org/ 10.3389/fmicb.2021.799012.
- Putz, E.J., Bayles, D.O., Alt, D.P., Nally, J.E. 2022. Complete Genome Sequence of Four Strains of Leptospira borgpetersenii serovar Hardjo isolated from Cattle in the Central United States. Journal of Genomics. 10. Pages 45-48. https://doi.org/10.7150/jgen.69822.
- Hamond, C., Lecount, K., Stuber, T., Putz, E.J., Bayles, D.O., Camp, P., Goris, M.G., Van Der Linden, H., Stone, N.E., Schlater, L., Sahl, J.W., Wagner, D.M., Nally, J.E. 2022. Bovine leptospirosis due to persistent renal carriage of Leptospira borgpetersenii serovar Tarassovi. Frontiers in Veterinary Science. 9. Article 848664. https://doi.org/10.3389/fvets. 2022.848664.
- Sykes, J., Reagan, K., Nally, J.E., Galloway, R., Haake, D. 2022. Role of diagnostics in epidemiology, management, surveillance, and control of leptospirosis. Pathogens. 11(4). Article 395. https://doi.org/10.3390/ pathogens11040395.
- Putz, E.J., Fernandes, L., Sivasankaran, S., Bayles, D.O., Alt, D.P., Lippolis, J.D., Nally, J.E. 2022. Some like it hot, some like it cold; Proteome comparison of Leptospira borgpetersenii serovar Hardjo strains propagated at different temperatures. Journal of Proteomics. 262(2022). Article 104602. https://doi.org/10.1016/j.jprot.2022.104602.
- Wilson-Welder, J.H., Olsen, S.C., Alt, D.P., Bayles, D.O., Han, S., Mansfield, K. 2022. Lesion material from Treponema-Associated Hoof Disease of wild elk induces disease pathology in the sheep Digital Dermatitis model. Frontiers in Veterinary Science. 8. Article 782149. https://doi.org/ 10.3389/fvets.2021.782149.
- Stone, N.E., Hall, C.M., Ortiz, M., Hutton, S., Santana-Popper, E., Celona, K.R., Williamson, C.H., Bratsch, N., Fernandes, L.G., Busch, J.D., Pearson, T., Rivera-Garcia, S., Soltero, F., Galloway, R., Weiner, Z., Hoffmaster, A.R., Sahl, J.E., Nally, J.E., Wagner, D.M. 2022. Divergent lineages of pathogenic Leptospira species are widespread and persisting in the environment in Puerto Rico, USA. PLOS Neglected Tropical Diseases. 16(5). e0009959. https://doi.org/10.1371/journal.pntd.0009959.
|
|