The immune response in horses involves a complex network of cells, tissues, and molecules that work together to protect the animal from pathogens and other harmful agents. This process includes both innate and adaptive immune mechanisms. Innate immunity provides the first line of defense and involves components such as physical barriers, phagocytic cells, and the complement system. Adaptive immunity, on the other hand, is characterized by the activation of lymphocytes and the production of antibodies, which provide a targeted response to specific antigens. Key components of the equine immune system include T cells, B cells, and various cytokines that facilitate communication between immune cells. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and implications of immune responses in equine health.
Liu M, Bordin A, Liu T, Russell K, Cohen N.Focusing on the first 3 weeks of life, this study examined the mRNA transcript development of different Th-type cytokines in foals in response to Rhodococcus equi infection in vitro. Results demonstrated the significant up-regulation in expression of Th1-, Th2-, and Th17-type cytokines (IFN-γ, IL-4, IL-6, IL-8, IL-12p35, IL-12p40, IL-17, IL-23p19, and TNF-α) in R. equi infection of bronchial alveolar lavage (BAL) cells of 10-day-old foals. Consequently, signature cytokines of 3 Th cell types, IFN-γ (Th1), IL-4 (Th2), and IL-17 (Th17), were used to compare temporal response patterns of circu...
Leclere M, Lavoie-Lamoureux A, Lavoie JP.Animal models have been developed to investigate specific components of asthmatic airway inflammation, hyper-responsiveness or remodelling. However, all of these aspects are rarely observed in the same animal. Heaves is a naturally occurring disease of horses that combines these features. It is characterized by stable dust-induced inflammation, bronchospasm and remodelling. The evaluation of horses during well-controlled natural antigen exposure and avoidance in experimental settings allows the study of disease mechanisms in the asymptomatic and symptomatic stages, an approach rarely feasible ...
Daly K, Proudman CJ, Duncan SH, Flint HJ, Dyer J, Shirazi-Beechey SP.We aimed to determine the effects of variations in dietary composition on equine gut microbiota and their fermentation products, and proposed that dietary modifications profoundly affect microbial ecosystems and their metabolites. Bacterial communities within the large intestine of three groups of horses were compared using oligonucleotide-RNA hybridisation methodology. Each group consisting of six horses was maintained on (1) a grass-only diet, (2) a concentrate diet (i.e. supplemented with hydrolysable carbohydrates) and (3) a concentrate diet but horses were affected by simple colonic obstr...
Muehlmann LA, Michelotto PV, Nunes EA, Grando FC, da Silva FT, Nishiyama A.Phagocytosis exerted by alveolar macrophages and neutrophils is crucial in the clearance of exogenous particles deposited in the airways. Therefore, substances that activate these phagocytes in the airways can exert important effects on the particle clearance rate. PAF, particularly, was proved to be a potent activator of several immune cells and was shown to be present in the equine lower airways in specific conditions, such as after exercise. The present study aimed to investigate if PAF is able to increase the phagocytic capacity and the production of superoxide anion in equine alveolar mac...
Burbelo PD, Bren KE, Ching KH, Coleman A, Yang X, Kariu T, Iadarola MJ, Pal U.Infection with Borrelia burgdorferi is common in horses and ponies from the New England and mid-Atlantic regions of the United States. Here, we evaluated luciferase immunoprecipitation systems (LIPS) for profiling antibody responses against three different antigenic targets for the diagnosis of equine B. burgdorferi infection. LIPS testing of horse serum samples suspected of Lyme infection revealed that approximately 75% of the horse samples (114/159) were seropositive against the synthetic VOVO antigen, comprising repeated immunodominant C6 epitopes as well as OspC immunodominant epitopes. A ...
Klier J, May A, Fuchs S, Schillinger U, Plank C, Winter G, Gehlen H, Coester C.Recurrent airway obstruction (RAO) in horses has become a common problem in stabled horses in industrialized countries and deserves new therapeutic strategies. CpG-oligodeoxynucleotides (CpG-ODNs) were developed as effective immunostimulating agents to induce a Th2/Th1 shift. These agents showed a beneficial therapeutic effect in allergic diseases with predominant Th2 immunoresponse. CpG-ODN delivery by gelatin nanoparticles (GNPs) resulted in enhanced cellular uptake in murine and human in vitro studies and was a starting point for the present trial. The aim of this study was to identify an o...
Waller AS, Paillot R, Timoney JF.Strangles caused by the host adapted Lancefield group C Streptococcus equi subspecies equi (S. equi) is a frequently diagnosed infectious disease of horses worldwide. Critical to the global success of S. equi is its ability to establish persistent infections within the guttural pouches of recovered apparently healthy horses that can result in transmission to in-contact animals. Recent research has identified key events in the S. equi genome, which occurred during its evolution from an ancestral strain of S. equi subspecies zooepidemicus, that may enhance its ability to evade host innate immune...
Lin YZ, Cao XZ, Li L, Li L, Jiang CG, Wang XF, Ma J, Zhou JH.The attenuated equine infectious anemia virus (EIAV) vaccine was the first attenuated lentivirus vaccine to be used in a large-scale application and has been used to successfully control the spread of equine infectious anemia (EIA) in China. To better understand the potential role of cytokines in the pathogenesis of EIAV infection and resulting immune response, we used branched DNA technology to compare the mRNA expression levels of 12 cytokines and chemokines, including IL-1α, IL-1β, IL-4, IL-10, TNF-α, IFN-γ, IP-10, IL-8, MIP-1α, MIP-1β, MCP-1, and MCP-2, in equine monocyte-derived mac...
Wu W, Blythe DC, Loyd H, Mealey RH, Tallmadge RL, Dorman KS, Carpenter S.Two variants of equine infectious anemia virus (EIAV) that differed in sensitivity to broadly neutralizing antibody were tested in direct competition assays. No differences were observed in the growth curves and relative fitness scores of EIAVs of principal neutralizing domain variants of groups 1 (EIAV(PND-1)) and 5 (EIAV(PND-5)), respectively; however, the neutralization-resistant EIAV(PND-5) variant was less infectious in single-round replication assays. Infectious center assays indicated similar rates of cell-to-cell spread, which was approximately 1,000-fold more efficient than cell-free ...
Alcott CJ, Sponseller BA, Wong DM, Davis JL, Soliman AM, Wang C, Hsu W.Ketamine has immunomodulating effects both in vitro and in vivo during experimental endotoxemia in humans, rodents, and dogs. Objective: Subanesthetic doses of ketamine will attenuate the clinical and immunologic responses to experimental endotoxemia in horses. Methods: Nineteen healthy mares of various breeds. Methods: Experimental study. Horses were randomized into 2 groups: ketamine-treated horses (KET; n = 9) and saline-treated horses (SAL; n = 10). Both groups received 30 ng/kg of lipopolysaccharide (LPS, Escherichia coli, O55:B5) 1 hour after the start of a continuous rate infusion (CRI)...
Wilson G, Cooper K, Williams J, Eastwood S, Peake C.The 2007 equine influenza (EI) outbreak in New South Wales (NSW) consisted of a central infected area that extended south from the lower New England Tableland, across the Hunter Valley, Central Coast and the Sydney basin, and a series of isolated clusters outside this area across rural NSW. The central area was assigned the status of a Purple Zone (Special Restricted Area, SRA) approximately 1 month after the outbreak commenced. Within this SRA, the eradication program's focus was to increase the proportion of horses immune to EI via vaccination, thus reducing the susceptible proportion to a l...
Read AJ, Finlaison DS, Gu X, Davis RJ, Arzey KE, Kirkland PD.During the equine influenza (EI) outbreak, two assays were used in parallel to diagnose the disease, to demonstrate freedom from infection in disease control zones and ultimately to demonstrate that EI virus had been eliminated from the Australian horse population. A longitudinal study of a population of naturally infected horses was established to determine the performance characteristics of these assays.
Kannegieter NJ, Frogley A, Crispe E, Kirkland PD.As part of the control measures of the equine influenza (EI) outbreak, in addition to the strategic use of vaccination to provide buffer zones around infected populations, approval was obtained to vaccinate Thoroughbred racing horses. We review the clinical expression of the disease and virus excretion in a population of racehorses that were exposed to EI approximately 7 days after administration of a single dose of the canarypox-vectored recombinant compared with a similar unvaccinated population of horses at a nearby racetrack. Although this study was undertaken opportunistically and under t...
Happold J, Rubira R.This study included 10 large Thoroughbred horse studs in the upper Hunter Valley of New South Wales and in southeast Queensland, Australia. The aims were to describe the EI epidemic in studs in the Special Restricted Area (Purple Zone) of NSW, to estimate seroprevalence among different groups of horses on these studs and to look for evidence of exposure to EI virus in horses on 'vaccinated' studs in southeast Queensland that were thought to have remained free of infection. As serology results from Queensland suggest that vaccination may have reduced the sensitivity of clinical surveillance to ...
Nogradi N, Slovis NM, Gebhart CJ, Wolfsdorf KE, McCracken JL, Scoggin CF, Kass PH, Mapes SM, Toth B, Lundquist ML, Pusterla N.Equine proliferative enteropathy caused by Lawsonia intracellularis is an emerging disease with as yet unaddressed preventative measures. The hypothesis of this study was that vaccination will prevent clinical and sub-clinical disease. Weanling Thoroughbreds (n=202) from Central Kentucky were randomly assigned into two groups (vaccinated and non-vaccinated). Vaccinated foals received 30 mL of an avirulent, live L. intracellularis vaccine intra-rectally twice, 30 days apart. Foals were monitored for clinical disease, total solids and average weight gain until yearling age. There was an overall ...
Wilkołek P, Szczepanik M, Gołyński M, Adamek L, Pomorska A, Maj-Martyniuk M, Sitkowski W.The main aim of this study was to compare selected nonspecific immunity parameters in 14 allergic and 12 healthy horses. Each animal was assessed according to the following parameters: in vitro functional capacity of phagocytic cells using the nitro blue tetrazolium chloride reduction test, both spontaneous (NBT) and zymozan stimulated (NBTs), and ingestion capacity of phagocytic cells using a phagocytic index test (IF) and percentage of phagocytosing neutrophils activity (%KF). Differences were demonstrated between the group of allergic horses, especially with severe allergy symptoms, and hea...
Santos CE, Marques LC, Zanette RA, Jesus FP, Santurio JM.A cutaneous Pythium insidiosum reinfection was diagnosed in an equine in Brazil. Lesions with focal presentation appeared 2 years apart. The first infection and even immunotherapy were not likely to develop enough immune response to prevent reinfection. The use of adjuvants should be considered in the immunotherapy of pythiosis.
Wagner B, Wimer C, Freer H, Osterrieder N, Erb HN.The recent increase in incidence, morbidity, and mortality of neurological disease induced by equine herpesvirus type 1 (EHV-1) has suggested a change of virulence of the virus. The exact mechanisms by which EHV-1 induces neurologic disease are not known. Environmental, viral, and host risk factors might contribute to neurological manifestation. Here, we investigated innate interferon-α (IFN-α), interleukin-10 (IL-10) and IL-4 responses after infection of equine peripheral blood mononuclear cells (PBMC) with EHV-1 using an available cytokine multiplex assay. Three viral strains representing ...
Sun L, Adams AA, Page AE, Betancourt A, Horohov DW.While interferon-gamma (IFNγ) plays an important role in protection against viral and intracellular bacterial infections, its production in neonates is deficient. Exposure to environmental antigens can promote the maturation of the immune system of neonatal humans and mice. We hypothesize that exposure to high level of microbial components would increase the production of IFNγ in neonatal foals. To test this hypothesis, one group of foals was placed into stalls three times a week for 8 weeks. A second group of foals remained on pasture. Air samples were collected from the barn and pasture fo...
Mérant C, Sheoran A, Timoney JF.Streptococcus equi (Se), the cause of equine strangles, is highly resistant to phagocytosis by neutrophils and is usually classified as an extracellular pathogen. Large numbers of the organism in tonsillar tissues during the acute phase of the disease are completely eliminated during convalescence by mechanisms not yet understood. In this study we demonstrate in an opsono-bactericidal assay and by cytometry and confocal microscopy that Se is interiorized and killed by equine blood monocytes. This finding supports the hypotheses that adaptive immune clearance is mediated by tonsillar macrophage...
Pusterla N, Mapes S, Gebhart C.The cell-mediated immune response to Lawsonia intracellularis, the agent of equine proliferative enteropathy (EPE), was investigated in vaccinated and naturally infected foals. Interferon (IFN)-γ gene expression was determined in peripheral blood mononuclear cells collected from vaccinated (n=6) and control foals (n=6) every 30 days for 180 days following first vaccine administration, and from clinically affected foals (n=16) within 7-10 days of diagnosing EPE. Seroconversion (immunoperoxidase monolayer assay titer ≥60) occurred in 5/6 vaccinated foals between 60 and 90 days following the f...
Nostell K, Bröjer J, Höglund K, Edner A, Häggström J.The aim of this study was to determine whether experimentally-induced endotoxaemia induced elevations in plasma cardiac troponin I (cTnI) concentrations in horses and how this might affect the incidence of cardiac arrhythmias. Eight Standardbred horses received an intravenous continuous rate infusion of endotoxin (total dose 500 ng/kg) for 6 h while being monitored using electrocardiography (ECG). Blood samples were collected before the start of the endotoxin infusion, every 60 min during the infusion, then 1, 2, 3, 8, 10 and 24 h post-infusion, and analysed for cTnI concentrations. One horse ...
Page AE, Loynachan AT, Bryant U, Stills HF, Adams AA, Gebhart CJ, Pusterla N, Horohov DW.Lawsonia intracellularis is the etiological agent of infectious intestinal hyperplasia for which several clinical diseases have been described including proliferative enteropathy (PE), intestinal adenomatosis, and ileitis. While initially recognized as the causative agent of PE in pigs, L. intracellularis is now viewed as an emerging cause of intestinal hyperplasia in a wide range of mammalian species, including horses. Equine proliferative enteropathy (EPE) has been reported worldwide though definitive diagnosis is difficult and the epidemiology of the disease remains poorly understood. Weanl...
Barbey C, Cauchard S, Cauchard J, Laugier C, Hartke A, Petry S.Rhodococcus equi remains a significant pathogen, causing severe pneumonia in foals. The development of vaccines and serologic diagnosis could be greatly facilitated by studying the humoral immune response to this equine pathogen. In this study, a crude extract of R. equi ATCC 33701-secreted proteins combined with the Montanide® ISA70 adjuvant was found to be highly immunogenic in mice with the highest titer of 99,000 on day 42 after the first subcutaneous immunization. This immune response was dependent on the quantity of proteins injected and the presence of adjuvant. By dot-blotting, eight ...
Lejeune JP, Sandersen C, Votion D, Caudron I, Vander Heyden L, Franck T, Ceusters J, Mouithys-Mickalad A, Niesten A, De La Rebière de Pouyade G....Intensive exercise induces a systemic inflammatory response characterised by an increase of blood neutrophil count and myeloperoxidase (MPO) release. Neutrophil elastase (NE) could also contribute to tissues lesions by its proteinase activities. Objective: To compare plasmatic NE concentrations before and after different forms of intensive exercise. Methods: EDTA blood samples were taken from 51 eventing horses (EvH) and 32 endurance horses (EndH) were sampled before the race (T0). Blood sampling was performed 2 h (T1) after completing either phase D of a one or 2 star eventing competition (n ...
Cywinska A, Gorecka R, Szarska E, Witkowski L, Dziekan P, Schollenberger A.Changes in serum levels of acute phase proteins (APPs) reflect the acute phase reaction, a rapid and nonspecific response to any tissue damage. Serum amyloid A (SAA) is the main APP in horses, which increases in various diseases, surgical injuries and after long distance endurance rides; however, this nonspecific parameter has not been investigated as an indicator of subclinical disorders, which may result in elimination during endurance competitions. Objective: To evaluate the serum concentration of SAA as a potential indicator for the status of horses prepared for long distance endurance rid...
Joubert P, Cordeau ME, Lavoie JP.Heaves in horses is characterized by lower airway neutrophilic inflammation, and reversible airflow obstruction. Pulmonary macrophages contribute to the inflammation observed in a number of human and animal pulmonary diseases, and it has been postulated that they are responsible for the neutrophilic inflammation present in heaves by the release of cytokines and chemokines. To test this hypothesis, the mRNA expression of TNF-α, IL-1β, IL-8, and MIP-2 by macrophages isolated from bronchoalveolar lavage cells was quantified using real-time RT-PCR in horses with heaves (n-6) and controls (n-6). ...
Afable MG, Shaik M, Sugimoto Y, Elson P, Clemente M, Makishima H, Sekeres MA, Lichtin A, Advani A, Kalaycio M, Tiu RV, O'Keefe CL, Maciejewski JP.A combination of horse anti-thymocyte globulin and cyclosporine produces responses in 60-70% of patients with severe aplastic anemia. We performed a phase II study of rabbit anti-thymocyte globulin and cyclosporine as first-line therapy for severe aplastic anemia. Methods: Twenty patients with severe aplastic anemia treated with rabbit anti-thymocyte globulin were compared to 67 historical control cases with matched clinical characteristics treated with horse anti-thymocyte globulin. Results: Response rates at 3, 6 and 12 months were similar for patients treated with rabbit anti-thymocyte glob...
Russell KE, Perkins PC, Hoffman MR, Miller RT, Walker KM, Fuller FJ, Sellon DC.Thrombocytopenia is a consistent finding and one of the earliest hematological abnormalities in horses acutely infected with equine infectious anemia virus (EIAV), a lentivirus closely related to human immunodeficiency virus. Multifactorial mechanisms, including immune-mediated platelet destruction and impaired platelet production, are implicated in the pathogenesis of EIAV-associated thrombocytopenia. This study was undertaken to investigate whether regenerative thrombopoiesis and platelet destruction occurred in ponies acutely infected with EIAV. Circulating large, immature platelets were in...
Bannai H, Mae N, Ode H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Equine herpesvirus type 1 (EHV-1) is a major cause of winter pyrexia in racehorses in two training centers (Ritto and Miho) in Japan. Until the epizootic period of 2008-2009, a vaccination program using a killed EHV-1 vaccine targeted only susceptible 3-year-old horses with low antibody levels to EHV-1 antigens. However, because the protective effect was not satisfactory, in 2009-2010 the vaccination program was altered to target all 3-year-old horses. To evaluate the vaccine's efficacy, we investigated the number of horses with pyrexia due to EHV-1 or equine herpesvirus type 4 (EHV-4) infecti...
Palmer JE, Benson CE, Whitlock RH.Fourteen ponies and 3 horses were inoculated with Ehrlichia risticii 2 to 20 months after a similar initial inoculation. Although all 17 had clinical signs of equine ehrlichial colitis after the first inoculation, 16 of 17 remained clinically normal following the second inoculation. The remaining pony had a transient fever and developed signs of depression. Before the initial inoculation, none of the animals had a detectable antibody titer to E risticii. All animals developed titers after the initial infection; however, a significant change of titer did not develop after reinoculation in most ...
Chirino-Trejo JM, Prescott JF.The antigens extracted from strains belonging to seven capsular serotypes of Rhodococcus equi, as well as from two wild strains isolated from pneumonic foals, were examined. Whole-cell antigens and soluble products present in broth culture supernatants were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroblotted onto nitrocellulose, and stained with serum from hyperimmunized rabbits or foals. Foal sera used included sera from pneumonic animals with known titer to equi factors; from animals bled monthly on a farm with enzootic pneumonia, and from animals bled mont...
Gilliam LL, Holbrook TC, Ownby CL, McFarlane D, Sleeper MM, Martin S, Levis K, Payton ME.Cardiac abnormalities are reported in rattlesnake-bitten horses. The prevalence and cause are unknown. Objective: To detect cardiac damage in rattlesnake-bitten horses by measuring cardiac troponin I (cTnI) and evaluating ECG recordings for presence of arrhythmias, and explore causes of this cardiac damage by measuring venom excretion, anti-venom antibodies, and tumor necrosis factor alpha (TNFα). Methods: A total of 20 adult horses with a clinical diagnosis of rattlesnake bite and 6 healthy adult horses. Methods: In a prospective clinical study, bite site swabs, blood samples, and urine samp...
Veldman JE, Keuning FJ, Molenaar I.Two times sublethal total body-X-irradiation with weekly local thymus irradiation established a T-cell deprived experimental model in rabbits. Humoral immunity reactions in draining lymph nodes have been analyzed histologically and at the submicroscopical level after challenge with Salmonella Java vaccine, horse spleen ferritin, horse-gamma-globulin, a chemical sensitizer oxazolone (2 phenyl-4-ethoxymethylene-5-oxazolone) and after skin allografting respectively. The time sequence studies in these animals with an 'isolated B-cell system' are compared with similar experiments in normal non-irra...
Rosas CT, Goodman LB, von Einem J, Osterrieder N.Infections of horses with equine herpesvirus type 1 (EHV-1) have garnered new attention over the last few years. Devastating outbreaks occurring worldwide, primarily of the neurologic form of the disease, have resulted in a reassessment of the control strategies, and particularly the prophylactic measures, that are necessary to keep the infection and spread of disease in check. Most of the available EHV-1 vaccines are based on preparations of inactivated virus, which are applied monovalently for prevention of EHV-1-caused abortion in pregnant mares or as part of multivalent vaccines to prevent...
Grosenbaugh DA, Backus CS, Karaca K, Minke JM, Nordgren RM.A new recombinant West Nile virus (WNV) vaccine has been licensed for use in horses. Prior to the availability of the recombinant vaccine in 2004, the only equine WNV vaccine available on the market had been an inactivated vaccine. Since the recombinant vaccine only expresses selected viral genes, the question could be posed as to whether a single dose of the recombinant vaccine would be effective in producing an anamnestic serologic response in horses previously vaccinated with an inactivated WNV vaccine. In this study we demonstrate that vaccination of horses with a canarypox-vectored recomb...
Mills PC, Ng JC, Kramer H, Auer DE.Five clinically healthy Thoroughbred geldings were injected with Freund's adjuvant 3 times to induce a chronic inflammatory response. Blood was collected at various times before and after adjuvant administration. Clinical responses (rectal temperature and general demeanor) were also monitored. Adjuvant injection induced increases in rectal temperature and plasma fibrinogen concentration (maximum levels measured were mean +/- s.d. 39.7 +/- 0.5 degrees C and 8.2 +/- 0.3 g/l, respectively), indicative of an inflammatory response. A mild clinical depression was also observed in the horses for 24 h...
El-Sheikh Ali H, Scoggin KE, Ruby R, Loynachan A, Boakari Y, Fernandes C, Dini P, Fedorka CE, Loux SC, Esteller-Vico A, Ball BA.Cervical remodeling is a critical component in both term and preterm labor in eutherian mammals. However, the molecular mechanisms underlying cervical remodeling remain poorly understood in the mare. The current study compared the transcriptome of the equine cervix (cervical mucosa (CM) and stroma (CS)) during placentitis (placentitis group, n = 5) and normal prepartum mares (prepartum group, n = 3) to normal pregnant mares (control group, n = 4). Transcriptome analysis identified differentially expressed genes (DEGs) during placentitis (5310 in CM and 907 in CS) and during the normal prepartu...
Andersen UV, Reinemeyer CR, Toft N, Olsen SN, Jacobsen S, Nielsen MK.Migrating Strongylus vulgaris and encysted cyathostomin larvae cause a localized inflammatory response in horses. It is unknown whether these larvae elicit a systemic acute phase response (APR), evidenced by changes in serum amyloid A (SAA), haptoglobin (Hp), iron (Fe), albumin, or albumin/globulin (A/G) ratio. In this study, 28 horses were randomly allocated to receive either pyrantel tartrate or a pelleted placebo formulation in their daily feed. Concurrent with treatment, all the horses were administered 5000 pyrantel-susceptible cyathostomin infective larvae once daily, 5 days a week, for ...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kokado H, Kondo T, Matsumura T.Immune responses were compared after intranasal (IN) and intramuscular (IM) vaccination of horses with a modified live equine herpesvirus type-1 (EHV-1) vaccine, and the protective effect after EHV-1 challenge was evaluated. IN- and IM-vaccinated groups (n = 5 each) showed significant rises in serum virus-neutralizing titers with increased levels of IgGa and IgGb antibodies after the first vaccination (P < 0.05). In nasal secretions, the IN group had significantly increased levels of IgA antibodies after vaccination (P < 0.05), whereas the response of the IM group was dominat...
Flaminio MJ, Rush BR, Shuman W.Inactivated Propionibacterium acnes is a biologic response modifier for treatment of non-specific respiratory disease in horses. The objectives of this investigation were to determine alterations in phagocytic activity, phenotypic expression of lymphocyte subpopulations and lymphokine-activated killing cell response in healthy young horses. Samples were collected on day 0, 7 and 14 of the investigation. Blood samples were obtained via jugular venipuncture and pulmonary leukocytes were recovered via bronchoalveolar lavage (BAL). Commercially available P. acnes (Eqstim) was administered intraven...
Witonsky S, Buechner-Maxwell V, Santonastasto A, Pleasant R, Werre S, Wagner B, Ellison S, Lindsay D.Equine protozoal myeloencephalitis (EPM) is a common and devastating neurologic disease of horses in the United States. Because some EPM-affected horses have decreased immune responses, immunomodulators such as levamisole have been proposed as supplemental treatments. However, little is known about levamisole's effects or its mechanism of action in horses. Objective: Levamisole in combination with another mitogen will stimulate a macrophage 1 (M1), dendritic cell 1 (DC1), T-helper 1 (CD4 Th1), and T-cytotoxic (CD8) immune response in equine peripheral blood mononuclear cells (PBMCs) in vitro a...
Zandoná Meleiro MC, de Carvalho HJC, Ribeiro RR, da Silva MD, Salles Gomes CM, Miglino MA, de Santis Prada IL.Racehorses are constantly exposed to stress. Aiming to verify the state of blood components and cortisol alterations during their routine and after races, phagocytosis and oxidative neutrophil burst assays, serum cortisol determination, erythrocytes apoptosis evaluation, lymphoproliferation assays, and blood count tests were performed in thirty Thoroughbred racehorses, which were divided in two groups. The samples were taken right after races (moment 0 d), during rest periods (-11 d, +1 d, +3 d), and after training (-8, +2, +5). In both groups, the phagocytosis showed a decrease in percentage ...
Ibrahim S, Hedia M, Taqi MO, Derbala MK, Mahmoud KGM, Ahmed Y, Ismail S, El-Belely M.So far the intimate link between serum microRNA (miRNA) and uterine inflammation in mares is unknown. We aimed (I) to investigate expression profile of eca-miR-155, eca-miR-223, eca-miR-17, eca-miR-200a, and eca-miR-205 (II) and to measure concentrations of interleukin 6 (IL-6), and prostaglandins (PGF and PGE) in serum of mares with healthy and abnormal uterine status (endometritis). This study was conducted on 80 Arabian mares: young (4-7 years), and old (8-14 years). Mares were divided into 48 sub-fertile (endometritis) and 32 fertile (control) at stud farms. Serum was collected for measuri...
Despite being one of the major causes of infertility in mares, the mechanisms responsible for equine endometrosis are still unclear and controversial. In the last few years, many investigations focused on local immune response modulation. Since it is generally accepted that endometrial fibrosis increases with age, we hypothesize that older mares could show altered local immune modulation, initiating a pro-inflammatory and tissue remodeling cascade of events that could lead to endometrosis. The aim of this study, indeed, is to evaluate and describe the local gene expression of genes involved in...
Anzai T, Sheoran AS, Kuwamoto Y, Kondo T, Wada R, Inoue T, Timoney JF.Streptococcus equi causes equine strangles. The acute disease has many of the hallmarks of an acute response including high fever, elevated plasma fibrinogen and neutrophilia, affects known to be mediated by proinflammatory cytokines. The objective of this study was to screen-culture supernatants from equine clinical isolates of S. equi and S. zooepidemicus for stimulation of mitogenic responses by horse peripheral blood mononuclear cells. Mitogenicity comparable to that of concanavalin A was detected in culture supernatants of S. equi strains but not in those of S. zooepidemicus. Mitogenicity...
Liu M, Bordin A, Liu T, Russell K, Cohen N.Focusing on the first 3 weeks of life, this study examined the mRNA transcript development of different Th-type cytokines in foals in response to Rhodococcus equi infection in vitro. Results demonstrated the significant up-regulation in expression of Th1-, Th2-, and Th17-type cytokines (IFN-γ, IL-4, IL-6, IL-8, IL-12p35, IL-12p40, IL-17, IL-23p19, and TNF-α) in R. equi infection of bronchial alveolar lavage (BAL) cells of 10-day-old foals. Consequently, signature cytokines of 3 Th cell types, IFN-γ (Th1), IL-4 (Th2), and IL-17 (Th17), were used to compare temporal response patterns of circu...
Drebert Z, Golke A, Cymerys J, Słońska A, Chmielewska A, Tucholska A, Bańbura MW.Equid herpesvirus type 1 (EHV-1) is a prevalent causative agent of equine diseases worldwide. After primary replication in the respiratory epithelium the virus disseminates systemically through a peripheral blood mononuclear cell (PBMC)-associated viraemia. EHV-1 is the only alphaherpes- virus known so far which is capable of establishing latent infection not only in neurons but also in immune system cells (mainly in lymphocytes and macrophages). Since leukocytes are not the target cells for viral replication but are used to transport EHV-1 to the internal organs, the questionremains how the v...
Hamza E, Torsteinsdottir S, Eydal M, Frey CF, Mirkovitch J, Brcic M, Wagner B, Wilson AD, Jungi TW, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland where Culicoides are absent. However, following importation into continental Europe where Culicoides are present, >or=50% of Icelandic horses (1st generation) develop IBH but
Piccione G, Rizzo M, Arfuso F, Giannetto C, Di Pietro S, Bazzano M, Quartuccio M.During early post-partum period both neonatal foals and peripartum mares are most susceptible to diseases. The aim of this study was to establish physiologic modifications of leukogram during the first month after foaling in mares and their newborn foals. To this end blood samples were collected from nine mares and nine foals (T0-T10), every three days from the 1st day until the 30th day after foaling. Samples were analysed for white blood cell (WBC) count and differential leucocyte counts. Two-way repeated measure analysis of variance (ANOVA) showed, in postpartum mares WBC showed significant...
Wise LM, Bodaan CJ, Mercer AA, Riley CB, Theoret CL.Wounds in horses often exhibit sustained inflammation and inefficient vascularization, leading to excessive fibrosis and clinical complications such as "proud flesh". Orf virus-derived proteins, vascular endothelial growth factor (VEGF)-E and interleukin (ovIL)-10, enhance angiogenesis and control inflammation and fibrosis in skin wounds of laboratory animals. Objective: The study aimed to determine if equine dermal cells respond to VEGF-E and ovIL-10. Equine dermal cells are expected to express VEGF and IL-10 receptors, so viral protein treatment is likely to alter cellular gene expression an...
Woodrow JS, Hines M, Sommardahl C, Flatland B, Lo Y, Wang Z, Sheats MK, Lennon EM.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 cel...
Dutta SK, Campbell DL.Blastic transformation of peripheral blood mononuclear cells and serum neutralization antibody levels for equine herpesivurs type 1 were measured in 19 mares from three farms at the time of termination of their pregnancy by normal foaling or viral abortion. The stimulation indexes of lymphocytes obtained from the mares from two farms (Farm 1 and 2) which had virus abortions, ranged from 2.1 to 10.8. But there was no significant difference in stimulation index levels between the aborting and normal foaling mares on these two farms. Equine herpesvirus type 1 was isolated from the mononuclear cel...
Van Andel AE, Magnarelli LA, Heimer R, Wilson ML.To characterize antibody response in horses with clinical signs of Ehrlichia equi infection. Methods: Prospective study. Methods: 13 horses with confirmed acute E equi infection. Methods: Sequential serum sampling was performed in Connecticut and New York during 1995 and 1996 to identify horses with naturally acquired equine granulocytic ehrlichiosis (EGE). Horses with clinical signs of EGE (i.e., fever without respiratory involvement) were confirmed as having E equi infection by polymerase chain reaction detection of ehrlichial DNA and by a minimum fourfold increase in total antibody titer by...
McGorum BC, Dixon PM, Halliwell RE.Intradermal end-point titres for commercial aqueous extracts of Micropolyspora faeni, Thermoactinomyces vulgaris and Aspergillus fumigatus were determined in control and chronic obstructive pulmonary disease (COPD) affected horses. The intradermal end-point titres of control and COPD-affected horses were not significantly different and values for individual horses for M. faeni, A. fumigatus and T. vulgaris were not correlated with the pulmonary dysfunction or with the bronchoalveolar lavage fluid neutrophilia which had been induced by previous inhalation challenges with these antigens and by '...
Bonin CP, Baccarin RY, Nostell K, Nahum LA, Fossum C, de Camargo MM.Engagement of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) is a master trigger of the deleterious effects of septic shock. Horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. Analysis of tlr4 promoters revealed high similarity among LPS-sensitive species (human, chimpanzee, and horse) and low similarity with LPS-resistant species (mouse and rat). Four conserved nuclear factor kappa B (NFκB) binding sites were found in the tlr4 promoter and two in the md2 promoter sequences that are likely to be t...
Phumoonna T, Barton MD, Vanniasinkam T, Heuzenroeder MW.Rhodococcus equi remains a significant bacterial pathogen, causing severe pyogranulomatous pneumonia in foals aged 1-3 months. There is no effective vaccine currently available for the prevention of R. equi pneumonia. DNA vaccines are known to offer specific advantages over conventional vaccines. The aim of this study was to demonstrate efficacy of our recombinant DNA vaccine candidates, namely pcDNA3-Re1, pcDNA3-Re3 and pcDNA3-Re5 by combining a heat shock protein GroEL2 to a virulence-associated protein A (VapA) from R. equi to protect C3H/He mice against the R. equi infection. VapA was show...
Deniz Ö, Ekinci G, Onmaz AC, Derelli FM, Fazio F, Aragona F, Hoven RVD.Rhodococcus equi (R. equi), a gram-positive facultative intracellular pathogen, is a common cause of pneumonia in foals and represents a major cause of disease and death. The aim of the present study was to investigate the time-depended changes in White Blood Cells (WBC), basophils (Baso), neutrophils (Neu), lymphocytes (Lymf), monocytes (Mon), eosinophils (Eos), platelet (PLT) counts, fibrinogen (Fbg) concentration, interferon (IFN-α, IFN-γ) and interleukins (IL-2 and IL-10) in foals with clinical R. equi pneumonia. The main treatment was with azithromycin-rifampicin for 14 days. Blood was ...
