@article{conley_till_berglund_jones_sheats_2023, title={A myristoylated alanine-rich C-kinase substrate (MARCKS) inhibitor peptide attenuates neutrophil outside-in & beta;(2)-integrin activation and signaling}, volume={17}, ISSN={["1933-6926"]}, url={https://doi.org/10.1080/19336918.2023.2233204}, DOI={10.1080/19336918.2023.2233204}, abstractNote={MARCKS is an actin and PIP2-binding protein that plays an essential role in neutrophil migration and adhesion; however, the molecular details regarding MARCKS function in these processes remains unclear. Neutrophil adhesion and migration also require the cell surface receptors β2-integrins. We hypothesized that MARCKS inhibition would alter neutrophil β2-integrin activation and signaling. We utilized a MARCKS-targeting peptide to inhibit MARCKS in inside-out and outside-in β2-integrin activation in neutrophils. MANS-mediated MARCKS inhibition had no significant effect on inside-out β2-integrin activation. MANS treatment significantly attenuated ICAM-1/Mn2+-stimulated static adhesion, cell spreading and β2-integrin clustering, suggesting a role for MARCKS function in outside-in β2-integrin activation. Additional work is needed to better understand the molecular mechanisms of MARCKS role in outside-in β2-integrin activation and signaling.}, number={1}, journal={CELL ADHESION & MIGRATION}, author={Conley, Haleigh and Till, Rebecca L. and Berglund, Alix K. and Jones, Samuel L. and Sheats, M. Katie}, year={2023}, month={Dec}, pages={1–16} } @misc{woodrow_sheats_cooper_bayless_2023, title={Asthma: The Use of Animal Models and Their Translational Utility}, volume={12}, ISSN={["2073-4409"]}, url={https://doi.org/10.3390/cells12071091}, DOI={10.3390/cells12071091}, abstractNote={Asthma is characterized by chronic lower airway inflammation that results in airway remodeling, which can lead to a permanent decrease in lung function. The pathophysiology driving the development of asthma is complex and heterogenous. Animal models have been and continue to be essential for the discovery of molecular pathways driving the pathophysiology of asthma and novel therapeutic approaches. Animal models of asthma may be induced or naturally occurring. Species used to study asthma include mouse, rat, guinea pig, cat, dog, sheep, horse, and nonhuman primate. Some of the aspects to consider when evaluating any of these asthma models are cost, labor, reagent availability, regulatory burden, relevance to natural disease in humans, type of lower airway inflammation, biological samples available for testing, and ultimately whether the model can answer the research question(s). This review aims to discuss the animal models most available for asthma investigation, with an emphasis on describing the inciting antigen/allergen, inflammatory response induced, and its translation to human asthma.}, number={7}, journal={CELLS}, author={Woodrow, Jane Seymour and Sheats, M. Katie and Cooper, Bethanie and Bayless, Rosemary}, year={2023}, month={Apr} } @article{woodrow_hines_sommardahl_flatland_lo_wang_sheats_lennon_2023, title={Initial investigation of molecular phenotypes of airway mast cells and cytokine profiles in equine asthma}, volume={9}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2022.997139}, abstractNote={Equine asthma is a naturally occurring lung disease characterized by chronic, partially reversible airway obstruction, pulmonary remodeling, and lower airway inflammation. Asthma is currently divided into two major groups, mild to moderate asthma (mEA) and severe asthma (sEA), but further subtyping by phenotype (i.e., clinical presentation) and/or endotype (i.e., cellular mechanisms) may be warranted. For this study, we were interested in further investigation of cellular and inflammatory characteristics of EA, including airway mast cells. The purpose of this study was to: (1) compare mast cell protease mRNA expression between healthy and asthmatic horses, (2) analyze the cytokine profile present in BALF of currently defined equine asthma groups, and (3) use these data to evaluate potential biomarkers of defined asthma groups. We hypothesized that there would be significant differences in the cellular mast cell phenotypes (i.e., mucosal vs. connective tissue) and cytokine profiles in the BALF of asthmatic vs. healthy horses and across asthma groups. We assert these characteristics may inform additional subtypes of equine asthma. Adult horses were recruited from the institution's teaching herd and clinical caseload. Mast cell protease gene expression of the BALF cellular component and multiplex bead immunoassay for cytokine concentrations in the BALF supernatant were investigated. Airway mast cells primarily expressed tryptase, with low levels of chymase. No significant changes in protease expression were detected across groups. Horses with severe asthma had increased TNF-α, CXCL-8, and IFN-γ concentrations in BALF supernatant. Multidimensional analysis demonstrated healthy and mEA horses have overlapping characteristics, with sEA separating from the other groups. This difference was primarily due to BALF neutrophil and lymphocyte concentrations. These study results further inform understanding of EA immunopathology, and future studies designed to investigate asthma phenotypes and endotypes. Ultimately, a better understanding of these groups could help identify novel therapeutic strategies.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Woodrow, Jane S. and Hines, Melissa and Sommardahl, Carla and Flatland, Bente and Lo, Yancy and Wang, Zhiping and Sheats, Mary Katie and Lennon, Elizabeth M.}, year={2023}, month={Jan} } @article{sheats_petritz_robertson_2023, title={Investigation of a Questionnaire Used to Measure Self-Perception of Self-Regulated Learning in Veterinary Students}, url={https://doi.org/10.3138/jvme-2023-0046}, DOI={10.3138/jvme-2023-0046}, abstractNote={In the United States, the veterinary medical curriculum is 4 years, and at most institutions, no more than one-third of that time is devoted to clinical training, meaning that graduates must continue learning post-graduation. Additionally, practicing veterinarians must keep up with new discoveries and techniques in the veterinary medical field, and may also choose to pursue specific interests or specialties post-graduation. For these reasons, it is essential that veterinarians be competent, self-regulated, life-long learners. Despite agreement regarding the importance of self-regulated learning (SRL) for veterinary professionals, there is currently a paucity of data available on self-regulated learning in veterinary students. The Self-Regulated Learning Perception Scale (SRLPS) is a 41-item instrument that has been previously validated in other graduate student populations, including medical students. It addresses four domains of self-regulated learning including motivation and action to learning, planning and goal setting, strategies for learning, and assessment and self-directedness. For this project, we hypothesized that the SRLPS would have high reliability among veterinary students. As part of a larger online survey, 82 veterinary students (years 1–4) voluntarily completed the SRLPS. The instrument was generally internally consistent, with the dimensions “Motivation and action to learn,” “Planning and goal setting,” “Strategies for learning and assessment,” and “Lack of self-directedness” having Cronbach's alpha values of .73, .8, .87, and .63 respectively. The SRLPS could have broad applications in veterinary educational practices and research, including assessing impact of courses on professional development and/or coaching/mentoring programs and better understanding short- and long-term educational and career outcomes for veterinarians.}, journal={Journal of Veterinary Medical Education}, author={Sheats, M. Katie and Petritz, Olivia A. and Robertson, James B.}, year={2023}, month={Sep} } @article{sheats_petritz_robertson_2023, title={Investigation of a questionnaire used to measure self-perception of self-regulated learning in veterinary students}, journal={Journal of Veterinary Medical Education}, author={Sheats, M.K. and Petritz, O. and Robertson, J.}, year={2023}, month={May} } @article{phelps_palekar_conley_ferrero_driggers_linder_kullman_reif_sheats_dewitt_et al._2023, title={Legacy and emerging per- and polyfluoroalkyl substances suppress the neutrophil respiratory burst}, volume={20}, ISSN={["1547-6901"]}, url={https://doi.org/10.1080/1547691X.2023.2176953}, DOI={10.1080/1547691X.2023.2176953}, abstractNote={Per- and polyfluoroalkyl substances (PFASs) are used in a multitude of processes and products, including nonstick coatings, food wrappers, and fire-fighting foams. These chemicals are environmentally-persistent, ubiquitous, and can be detected in the serum of 98% of Americans. Despite evidence that PFASs alter adaptive immunity, few studies have investigated their effects on innate immunity. The report here presents results of studies that investigated the impact of nine environmentally-relevant PFASs [e.g. perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid potassium salt (PFOS-K), perfluorononanoic acid (PFNA), perfluorohexanoic acid (PFHxA), perfluorohexane sulfonic acid (PFHxS), perfluorobutane sulfonic acid (PFBS), ammonium perfluoro(2-methyl-3-oxahexanoate) (GenX), 7H-perfluoro-4-methyl-3,6-dioxa-octane sulfonic acid (Nafion byproduct 2), and perfluoromethoxyacetic acid sodium salt (PFMOAA-Na)] on one component of the innate immune response, the neutrophil respiratory burst. The respiratory burst is a key innate immune process by which microbicidal reactive oxygen species (ROS) are rapidly induced by neutrophils in response to pathogens; defects in the respiratory burst can increase susceptibility to infection. The study here utilized larval zebrafish, a human neutrophil-like cell line, and primary human neutrophils to ascertain whether PFAS exposure inhibits ROS production in the respiratory burst. It was observed that exposure to PFHxA and GenX suppresses the respiratory burst in zebrafish larvae and a human neutrophil-like cell line. GenX also suppressed the respiratory burst in primary human neutrophils. This report is the first to demonstrate that these PFASs suppress neutrophil function and support the utility of employing zebrafish larvae and a human cell line as screening tools to identify chemicals that may suppress human immune function.}, number={1}, journal={JOURNAL OF IMMUNOTOXICOLOGY}, author={Phelps, Drake W. and Palekar, Anika I. and Conley, Haleigh E. and Ferrero, Giuliano and Driggers, Jacob H. and Linder, Keith E. and Kullman, Seth W. and Reif, David M. and Sheats, M. Katie and DeWitt, Jamie C. and et al.}, year={2023}, month={Dec} } @misc{conley_sheats_2023, title={Targeting Neutrophil beta(2)-Integrins: A Review of Relevant Resources, Tools, and Methods}, volume={13}, ISSN={["2218-273X"]}, url={https://doi.org/10.3390/biom13060892}, DOI={10.3390/biom13060892}, abstractNote={Neutrophils are important innate immune cells that respond during inflammation and infection. These migratory cells utilize β2-integrin cell surface receptors to move out of the vasculature into inflamed tissues and to perform various anti-inflammatory responses. Although critical for fighting off infection, neutrophil responses can also become dysregulated and contribute to disease pathophysiology. In order to limit neutrophil-mediated damage, investigators have focused on β2-integrins as potential therapeutic targets, but so far these strategies have failed in clinical trials. As the field continues to move forward, a better understanding of β2-integrin function and signaling will aid the design of future therapeutics. Here, we provide a detailed review of resources, tools, experimental methods, and in vivo models that have been and will continue to be utilized to investigate the vitally important cell surface receptors, neutrophil β2-integrins.}, number={6}, journal={BIOMOLECULES}, author={Conley, Haleigh E. and Sheats, M. Katie}, year={2023}, month={Jun} } @article{bayless_cooper_sheats_2022, title={Investigation of plasma cell-free DNA as a potential biomarker in horses}, volume={2}, ISSN={["1943-4936"]}, url={https://doi.org/10.1177/10406387221078047}, DOI={10.1177/10406387221078047}, abstractNote={Plasma cell-free DNA (cfDNA) is a biomarker of ischemia, systemic inflammation, and mortality in humans with gastrointestinal disease. Cell-free DNA has not been investigated as a biomarker for equine colic, to our knowledge. We hypothesized that cfDNA could be measured accurately in neat equine plasma using a benchtop fluorometer and that plasma cfDNA would be elevated in emergency patients compared to healthy horses. Plasma was obtained from blood collected in Roche DNA stabilizing tubes. We used the Qubit 4 fluorometer and 1× dsDNA HS assay kit to measure cfDNA concentration in neat patient plasma and following DNA extraction of plasma with a commercial kit. Assay precision and linearity of dilution were satisfactory for neat plasma cfDNA, but DNA spike and recovery results were variable. Further, cfDNA concentrations in paired neat plasma and extracted-plasma samples (n = 66) were not correlated. Median extracted-plasma cfDNA was higher in emergency patients (n = 50) and a subgroup of colic patients (n = 36), compared to healthy horses (n = 19). Our results with extracted-plasma samples provide proof of concept for further investigation of plasma cfDNA as a biomarker in horses.}, number={3}, journal={JOURNAL OF VETERINARY DIAGNOSTIC INVESTIGATION}, publisher={SAGE Publications}, author={Bayless, Rosemary L. and Cooper, Bethanie L. and Sheats, M. Katie}, year={2022}, month={Feb} } @article{bayless_bayless_sheats_jones_2022, title={Withaferin A Inhibits Neutrophil Adhesion, Migration, and Respiratory Burst and Promotes Timely Neutrophil Apoptosis}, volume={9}, ISSN={["2297-1769"]}, url={https://europepmc.org/articles/PMC9247543}, DOI={10.3389/fvets.2022.900453}, abstractNote={Neutrophils play a major role in many equine conditions, including equine asthma, laminitis, and intestinal ischemia and reperfusion injury, and therefore represent an attractive target for innovative therapeutic approaches. Novel strategies for reducing neutrophilic inflammation include modulation of neutrophil functions and lifespan. Withaferin A (WFA) is a phytochemical with well-established in vitro and in vivo anti-inflammatory properties, but its direct effects on neutrophils are largely unknown. We hypothesized that WFA would inhibit adhesion, migration, and respiratory burst by equine neutrophils and promote timely apoptosis of primed equine neutrophils. Consistent with this hypothesis, our data show that WFA causes a significant, concentration-dependent inhibition of equine neutrophil adhesion, migration, and respiratory burst in response to diverse stimuli. Further, WFA treatment increased apoptosis of equine neutrophils exposed to GM-CSF for 24 h. This pro-apoptotic effect of WFA was not observed in unprimed neutrophils, nor at the 2-h time point relevant to our functional neutrophil experiments. Our data demonstrate that WFA may reduce neutrophil-mediated inflammation through multiple mechanisms, including suppression of inflammatory responses and promotion of apoptosis. Additional research is needed to elucidate the molecular mechanisms for these effects and evaluate the potential clinical use of WFA in veterinary and human patients.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Bayless, Rosemary and Bayless, RL and Sheats, M. Katie and Jones, Sam}, editor={Bayless, RosemaryEditor}, year={2022}, month={Jun} } @article{sheats_burke_robertson_fiebrandt_fogle_2021, title={Development and Formative Evaluation of a Low-Fidelity Equine Castration Model for Veterinary Education}, volume={8}, ISSN={["2297-1769"]}, url={https://europepmc.org/articles/PMC8476848}, DOI={10.3389/fvets.2021.689243}, abstractNote={Entrustable Professional Activities (EPAs) are units of activity that early-stage professionals perform in the workplace that necessitate simultaneous integration of multiple competencies. EPA #6 requires students to perform a common surgical procedure on a stable patient, including pre-operative and post-operative management. Castration is one of the most common surgeries performed by equine primary care practitioners and is considered an “entry-level competency” for veterinary graduates entering equine private practice, however, to our knowledge there are no equine castration models available for veterinary student education. Therefore, we developed an inexpensive, low-fidelity model of equine field castration and evaluated it using a mixed-methods approach. Two different groups of students, with or without model experience, completed surveys before and after live horse castration. Students who used the model also completed model specific surveys. Videos of the students completing the model were evaluated by at least two different equine veterinary faculty using a 15-point rubric, and inter-rater reliability of the rubric was determined. After completing the model, students reflected on strengths and weaknesses of their performance. From our student survey results, we determined that student attitudes toward the model were mostly positive. Interestingly, there were several student attitudes toward the model that became significantly more favorable after live horse castration. Prior to live horse castration, there was no significant difference in confidence in model vs. no-model groups. Following live horse castration, students who used the model had higher confidence in procedure preparation and hand-ties than students who did not use the model, but they had lower scores for confidence during patient recovery. When reflecting on model castration, students most commonly cited preparation and surgical description as strengths, and ligature placement and hand-ties as weaknesses. Experts provided several suggestions to improve the model, including incorporation of emasculators and the need for better model stabilization. Our findings suggest that both students and veterinary educators feel that this low-fidelity model has educational value. Rubric performance metrics were favorable, but additional steps are needed to improve grading consistency among educators. Future research will determine whether student performance on the model is predictive of competence score during live-horse castration.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Sheats, M. Katie and Burke, Megan J. and Robertson, James B. and Fiebrandt, Katherine E. and Fogle, Callie A.}, year={2021}, month={Sep} } @article{davis_sheats_2021, title={Differential gene expression and Ingenuity Pathway Analysis of bronchoalveolar lavage cells from horses with mild/moderate neutrophilic or mastocytic inflammation on BAL cytology}, volume={234}, ISSN={["1873-2534"]}, url={https://doi.org/10.1016/j.vetimm.2021.110195}, DOI={10.1016/j.vetimm.2021.110195}, abstractNote={Mild to moderate equine asthma syndrome (mEAS) affects horses of all ages and breeds. To date, the etiology and pathophysiology of mEAS are active areas of research, and it remains incompletely understood whether mEAS horses with different immune cell 'signatures' on BAL cytology represent different phenotypes, distinct pathobiological mechanisms (endotypes), varied environmental conditions, disease severity, genetic predispositions, or all of the above. In this descriptive study, we compared gene expression data from BAL cells isolated from horses with normal BALF cytology (n = 5), to those isolated from horses with mild/moderate neutrophilic inflammation (n = 5), or mild/moderate mastocytic inflammation (n = 5). BAL cell protein lysates were analyzed for cytokine/chemokine levels using Multiplex Bead Immunoassay, and for select proteins using immunoblot. The transcriptome, determined by RNA-seq and analyzed with DEseq2, contained 20, 63, and 102 significantly differentially expressed genes in horses with normal vs. neutrophilic, normal vs. mastocytic, and neutrophilic vs. mastocytic BALF cytology, respectively. Pathway analyses revealed that BAL-isolated cells from horses with neutrophilic vs. normal cytology showed enrichment in inflammation pathways, and horses with mastocytic vs. normal cytology showed enrichment in pathways involved in fibrosis and allergic reaction. BAL cells from horses with mastocytic mEAS, compared to neutrophilic mEAS, showed enrichment in pathways involved in alteration of tissue structures. Cytokine analysis determined that IL-1β was significantly different in the lysates from horses with neutrophilic inflammation compared to those with normal or mastocytic BAL cytology. Immunoblot revealed significant difference in the relative level of MMP2 in horses with neutrophilic vs. mastocytic mEAS. Upregulation of mRNA transcripts involved in the IL-1 family cytokine signaling axis (IL1a, IL1b, and IL1R2) in neutrophilic mEAS, as well as KIT mRNA in mastocytic mEAS, are novel, potentially clinically relevant, findings of this study. These findings further inform our understanding of inflammatory cell subtypes in mEAS.}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, publisher={Elsevier BV}, author={Davis, Kaori Uchiumi and Sheats, M. Katie}, year={2021}, month={Apr} } @article{westerman_sheats_elfenbein_2021, title={Sulfate Import in Salmonella Typhimurium Impacts Bacterial Aggregation and the Respiratory Burst in Human Neutrophils}, volume={89}, ISSN={["1098-5522"]}, DOI={10.1128/IAI.00701-20}, abstractNote={During enteric salmonellosis, neutrophil-generated reactive oxygen species alter the gut microenvironment, favoring survival of Salmonella Typhimurium. While type 3 secretion system 1 (T3SS-1) and flagellar motility are potent Salmonella Typhimurium agonists of the neutrophil respiratory burst in vitro, neither of these pathways alone is responsible for stimulation of a maximal respiratory burst.}, number={6}, journal={INFECTION AND IMMUNITY}, author={Westerman, T. L. and Sheats, M. K. and Elfenbein, J. R.}, year={2021}, month={Jun} } @article{davis_sheats_2021, title={The Role of Neutrophils in the Pathophysiology of Asthma in Humans and Horses}, volume={44}, url={https://doi.org/10.1007/s10753-020-01362-2}, DOI={10.1007/s10753-020-01362-2}, number={2}, journal={Inflammation}, publisher={Springer Science and Business Media LLC}, author={Davis, Kaori Uchiumi and Sheats, M. Katie}, year={2021}, month={Apr}, pages={450–465} } @article{woodrow_hines_sommardahl_flatland_davis_lo_wang_sheats_lennon_2020, title={Multidimensional Analysis of Bronchoalveolar Lavage Cytokines and Mast Cell Proteases Reveals Interferon-γ as a Key Biomarker in Equine Asthma Syndrome}, volume={2}, url={https://doi.org/10.1101/2020.02.24.956573}, DOI={10.1101/2020.02.24.956573}, abstractNote={Abstract Naturally-occurring equine asthma is an inflammatory lung disease characterized by chronic, partially reversible airway obstruction, pulmonary remodeling and lower airway inflammation. The cytokine profiles that distinguish asthma groups or subtypes in horses have not been systematically classified, and mast cell phenotypes, which, in human asthma, correlate with asthma type, lung function, and response to therapy, have not been well-described in horses. The purpose of this study was to: (1) compare mast cell protease mRNA expression between healthy and asthmatic horses, (2) analyze the cytokine profile present in BALF of currently defined equine asthma groups, and (3) use these data to evaluate potential biomarkers of defined asthma groups. Mast cell protease gene expression and select cytokine gene expression in cells isolated from BALF, and BALF multiplex cytokine assays were performed. Multidimensional analysis demonstrated that IFNγ differentiates severe from moderate asthma, and that TNFα and CXCL8 are key biomarkers of equine asthma subtype. Expression of chymase mRNA, a mast cell-specific protease, was significantly decreased in horses with mastocytic asthma. These results will help further define EAS immunopathology, which could improve understanding and definitions of asthma groups, while also potentially identify novel therapeutic strategies.}, publisher={Cold Spring Harbor Laboratory}, author={Woodrow, Jane S. and Hines, Melissa and Sommardahl, Carla and Flatland, Bente and Davis, Kaori U. and Lo, Yancy and Wang, Zhiping and Sheats, Mary Katherine and Lennon, Elizabeth M.}, year={2020}, month={Feb} } @misc{sheats_2019, title={A Comparative Review of Equine SIRS, Sepsis, and Neutrophils}, volume={6}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2019.00069}, abstractNote={The most recent definition of sepsis in human medicine can be summarized as organ dysfunction caused by a dysregulated host response to infection. In equine medicine, although no consensus definition is available, sepsis is commonly described as a dysregulated host systemic inflammatory response to infection. Defense against host infection is the primary role of innate immune cells known as neutrophils. Neutrophils also contribute to host injury during sepsis, making them important potential targets for sepsis prevention, diagnosis, and treatment. This review will present both historical and updated perspectives on the systemic inflammatory response (SIRS) and sepsis; it will also discuss the impact of sepsis on neutrophils, and the impact of neutrophils during sepsis. Future identification of clinically relevant sepsis diagnosis and therapy depends on a more thorough understanding of disease pathogenesis across species. To gain this understanding, there is a critical need for research that utilizes a clearly defined, and consistently applied, classification system for patients diagnosed with, and at risk of developing, sepsis.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Sheats, M. Katie}, year={2019}, month={Mar} } @article{freese_sheats_2019, title={A Suspected Case of Rocky Mountain Spotted Fever in an Adult Horse in the Southeastern United States}, volume={78}, ISSN={["1542-7412"]}, DOI={10.1016/j.jevs.2019.05.003}, abstractNote={A 20-year-old Paint gelding was evaluated for fever of unknown origin. History and clinical signs were consistent with potential tick-borne disease. Samples were collected and submitted for tick-borne disease panel, herpes virus, complete blood count, and serum biochemistry. Based on physical examination findings and vaccination history, the gelding was treated for suspected tick-borne disease with oxytetracycline (8 mg/kg intravenously BID) for 5 days, followed by doxycycline (10 mg/kg PO BID) for an additional 5 days. Although titers to Borrelia burgdorferi, Anaplasma phagocytophilum, and Neorickettsia risticii on Days 4 and 8 were negative, the Rickettsia rickettsii titer went from 1:1,600 on Day 4 to 1:800 on Day 8, 1:100 on Day 21, and was seronegative by Day 38. Although complete blood polymerase chain reaction for Rickettsia rickettsii was negative, the clinical and serologic features of this case are extremely consistent with clinical cases of Rocky Mountain Spotted Fever (RMSF) described in both dogs and humans. Therefore, we submit this case report to document suspected clinical infection of an adult horse in the southeastern United States with Rickettsia rickettsii, the causative agent of RMSF. Other relevant differentials (i.e., Rickettsia parkeri, Theileria equi, and Babesia caballi) are also discussed.}, journal={JOURNAL OF EQUINE VETERINARY SCIENCE}, author={Freese, Stephanie and Sheats, M. Katie}, year={2019}, month={Jul}, pages={134–137} } @article{davis_sheats_2019, title={Bronchoalveolar Lavage Cytology Characteristics and Seasonal Changes in a Herd of Pastured Teaching Horses}, volume={6}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2019.00074}, abstractNote={Equine asthma syndrome (EAS) is a common problem that affects horses of any age. Severe EAS is reported to affect 10-20% of adult horses in the northern hemisphere, while mild/moderate EAS is reported to affect 60-100% of adult horses, depending on the population and geographic region. For both severe and mild/moderate EAS, the presence of lower airway inflammation is attributed to airborne “triggers” such as dust, mold and bacterial components that horses encounter in hay and stable-environments; and treatment recommendations for horses with EAS often include full-time pasture turnout. The caveat to this recommendation is horses with summer-pasture associated EAS (SP-EAS), who experience allergic lower airway inflammation when exposed to summer pasture. The prevalence of EAS in horses on pasture that do not have SP-EAS has not been reported. The purpose of this study was to use bronchoalveolar lavage (BAL) cytology to determine the prevalence of EAS in a herd of pastured, adult research horses with no history of respiratory disease. The horses were members of a teaching animal herd housed on pasture in the southeastern United States and fed round-bale Bermuda-grass hay. BAL fluid (BALF) cytology was analyzed in both summer (May-August 2017) and winter (November 2017-February 2018). Similar to previous reports, the prevalence of severe EAS in our study population was 10% in summer and 4.3% in winter. The prevalence of mild/moderate EAS was 60% in summer and 87% in winter. The high prevalence of mild/moderate EAS in this population was unexpected, given the 24-hour, year-round pasture environment and the lack of history of respiratory disease. Additionally, 61.1% of horses with both summer and winter data had a different BALF cytology profile between the two seasons. To the authors’ knowledge, this is the first study to use BAL cytology to diagnose, and monitor changes in, EAS phenotype in pastured adult horses. These results help to inform discussions regarding prevalence of EAS in pastured, adult horses in the southeastern region of North America.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Davis, Kaori Uchiumi and Sheats, Mary Katherine}, year={2019}, month={Mar} } @article{sheats_davis_poole_2019, title={Comparative Review of Asthma in Farmers and Horses}, volume={19}, url={https://doi.org/10.1007/s11882-019-0882-2}, DOI={10.1007/s11882-019-0882-2}, abstractNote={Farmers are routinely exposed to organic dusts and aeroallergens that can have adverse respiratory health effects including asthma. Horses are farm-reared large animals with similar exposures and can develop equine asthma syndrome (EAS). This review aims to compare the etiology, pathophysiology, and immunology of asthma in horses compared to farmers and highlights the horse as a potential translational animal model for organic dust-induced asthma in humans.Severe EAS shares many clinical and pathological features with various phenotypes of human asthma including allergic, non-allergic, late onset, and severe asthma. EAS disease features include variable airflow obstruction, cough, airway hyperresponsiveness, airway inflammation/remodeling, neutrophilic infiltrates, excess mucus production, and chronic innate immune activation. Severe EAS is a naturally occurring and biologically relevant, translational animal disease model that could contribute to a more thorough understanding of the environmental and immunologic factors contributing to organic dust-induced asthma in humans.}, number={11}, journal={Current Allergy and Asthma Reports}, publisher={Springer Science and Business Media LLC}, author={Sheats, M. Katie and Davis, Kaori U. and Poole, Jill A.}, year={2019}, month={Nov} } @misc{sheats_yin_fang_park_crews_parikh_dickson_adler_2019, title={MARCKS and Lung Disease}, volume={60}, ISSN={["1535-4989"]}, DOI={10.1165/rcmb.2018-0285TR}, abstractNote={Section:ChooseTop of pageAbstract <