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.
Migliorisi A, Nottle B, Smanik LE, Nout-Lomas YS, Hassel DM.To (1) compare total nucleated cell count (TNCC) and neutrophil-to-lymphocyte ratio (NLR) at admission between horses with medically managed, large intestinal (LI) and small intestinal (SI) surgical colic; (2) compare TNCC and NLR between survivors and nonsurvivors; and (3) investigate associations between TNCC, NLR, surgical intervention, and outcome. Methods: Case-control study. Methods: Single, academic institution. Methods: A total of 341 adult horses diagnosed with noninfectious medical or surgical colic. Results: Admission TNCC did not differ between the medical and combined surgical gro...
Frontiers in geneticsAugust 29, 2025
Volume 16 1651628 doi: 10.3389/fgene.2025.1651628
Su Y, Ren W, Ma S, Meng J, Yao X, Zeng Y, Li Z, Li L, Wang R, Wang J.This study employed Yili horses participating in a 5000-meter race as a model to investigate exercise-induced gene expression alterations in peripheral blood using whole transcriptome sequencing. Jugular vein blood samples from the three leading horses were collected pre- and immediately post-race, yielding 2,171 differentially expressed mRNAs (2,080 upregulated, 91 downregulated), 4,375 differentially expressed LncRNAs (4,354 upregulated), and 68 differentially expressed circRNAs (64 upregulated). GO/KEGG analyses demonstrated significant enrichment of differential mRNAs in transmembrane tran...
Isoardi KZ, Chiew AL, Dhital A, Isbister GK.Antivenom is used to treat systemic envenomation and is immunoglobulin G raised from animals, mainly horses, inoculated by venom. Unassigned: We report two cases of life-threatening anaphylaxis following the administration of antivenom in patients with known horse dander allergy. Unassigned: A 14-year-old boy presented with redback spider envenomation. He had a known horse dander allergy. He received antivenom to treat severe pain and developed immediate severe anaphylaxis requiring endotracheal intubation and inotropic support. A 52-year-old man with horse dander allergy presented with suspec...
Modrý D, Hainisch EK, Fuehrer HP, Kniha E, Unterköfler MS, Sádlová J, Jahn P, Řeháková K, Sedlák K, Votýpka J.We report 4 cases of equine cutaneous leishmaniasis caused by Leishmania martiniquensis in Czech Republic and Austria, outside the known endemic range of leishmaniases. The parasite should be considered as a potential cause of cutaneous lesions in horses; the risk for zoonotic transmission to immunocompromised humans is anticipated throughout central Europe.
Chwirot A, Niedźwiedź A, Stygar D, Siwińska N, Paszkowska M, Niżański W, Napierkowska S, Migdał P, Kublicka A, Marynowska M, Matczuk A....This study investigated the presence of antibodies to human adenovirus type 36 (HAdV-D36) in horses with different metabolic statuses, including normal, overweight, and those diagnosed with equine metabolic syndrome (EMS). A total of 151 serum samples were tested, of which 47.6% were positive for anti-HAdV-D36 antibodies. Although the horses were confirmed to be susceptible to HAdV-D36 infection, there was no significant correlation between infection and blood glucose or cholesterol levels. However, the triglyceride levels showed significant differences-they were particularly elevated in the s...
Alves-Junior CDB, Ferreira TC, Nunes-Pinheiro DCS.This study evaluated the dynamics of blood immune-inflammatory biomarkers in response to exercise-induced changes in jumping horses. Methods: For this purpose, adult Brazilian Sport Horses (n = 9), aged 10.1 years, both sexes, underwent a specific training test consisting of warm-up, flatwork, and jumping exercises, and recovery on a 900 m sand track over 40 min. Clinical examinations and blood collections were performed at three time points: before (T0), immediately after (T1), and 1 h after (T2) the final exercise. Hematologic and biochemical parameters, such as total protein, gl...
Cormier KV, Fontenot RL, Eddy A, Williams ML, Wills RW, Jumper WI, Mochal-King CA.The objective of the study was to evaluate effects of intra-articular decellularized porcine amnion/chorion suspension (dPACLS) in horses. Methods: Controlled, randomized, prospective study. Methods: A total of 10 adult horses. Methods: One randomly selected radiocarpal joint (RCJ) was injected with a high dose (HD) of 50 mg (n = 5) or low dose (LD) of 5 mg of dPACLS (n = 5). The contralateral RCJ received saline as control. Systemic serum amyloid A (SAA), synovial fluid analysis (including SAA) and subjective lameness evaluation were performed prior to injection (time 0) and 24, 4...
Marchio SP, El-Sheikh Ali H, Scott MA, Barbosa Fernandes C, Scoggin KE, Troedsson M, Boakari Y.Despite its critical role in protecting the fetus, the amniotic membrane remains poorly understood in the context of disease response. The equine amniotic membrane is an important physical barrier to the amniotic compartment, and there is evidence that it may contribute to surfactant synthesis. Surfactants are essential for normal fetal lung development, and disruptions in its availability may be linked to future neonatal complications. Therefore, understanding the molecular changes that occur in fetal-maternal tissues during placentitis would clarify how this condition leads to abortion, pret...
Sahoo DK, Wong D, Paital B, Ruby RE, Patel A.The progression of inflammation during sepsis represents a multifaceted biological cascade that requires effective therapeutic interventions to improve survival. In septic neonatal foals, oxidative stress (OS) arises due to a compromised antioxidant defense system. Oxidative stress may disrupt the functionality of redox-sensitive organelles, such as the endoplasmic reticulum (ER). Endoplasmic reticulum stress disorder affects multiple cellular signaling pathways, including redox balance, inflammation, and apoptosis, and contributes to the pathogenesis of sepsis. The study aimed to elucidate wh...
Jebbawi F, Olomski F, Inversini V, Keller G, Rhiner T, Waldern N, Lam J, Pantelyushin S, Canonica F, Birkmann K, Johansen P, Kündig TM....Skin allergies are among the most frequent types of allergies, where continuous investigation of the pathological immune mechanisms is required for a better understanding and a more effective treatment of the disease. In this study, we aimed to investigate the effect of interleukin (IL)-5 vaccination on allergen-specific IgE antibodies as well as T cell cytokine modulation in skin allergy using a mouse model and a naturally occurring disease in horses. Methods: Ovalbumin (OVA)-sensitized mice, as well as horses affected by equine insect bite hypersensitivity (IBH) were administered an anti-IL-...
Janshoff S, Plümers R, Ramsauer AS, Cavalleri J, Vollmer T, Todt D, Brown RJP, Steinmann E, Gömer A.The emergence of new pathogens poses a significant threat to global health, exacerbated by climate change, biodiversity loss, and increased globalization. Ticks, as vectors for various pathogens, contribute to the rising incidence of diseases. Surveillance programs are crucial for identifying and controlling emerging pathogens. This study focuses on the Alongshan virus (ALSV), a segmented flavi-like virus first identified in humans in China in 2017. Despite its ability to infect a wide range of mammals, the natural hosts and transmission pathways of ALSV remain poorly understood. Therefore, we...
Lendl L, Wirth C, Merle R, Barton AK.Mild-moderate equine asthma (MEA) is a very common but underdiagnosed pulmonary disease in horses, with mild cases not showing clinical respiratory signs. This study evaluates the influence of a standardized lunging exercise test (SLET) on bronchoalveolar lavage fluid (BALF) cytology in MEA horses. We hypothesized that SLET would increase the total nucleated cell count (TNCC) and/or percentages of inflammatory cells associated with EA. In a prospective, randomized, non-blinded, between-subjects study design of two independent groups, 39 horses (17 mild and 22 moderate) were included. They were...
Hobbs KJ, Ueda Y, Le Sueur ANV, Cooper BL, Burke MJ, Sheats MK.To determine the effect of hemoperfusion with a polymer-based column on systemic cytokine concentrations and neutrophil dysfunction in lipopolysaccharide-treated horses in vivo. Unassigned: 6 university-owned horses received 60 ng/kg lipopolysaccharide, IV, as a bolus and then 60 ng/kg, IV, as a constant rate infusion over 1 hour. Endotoxemia was confirmed by clinical signs and neutropenia. In a crossover model that was completed from January 2024 through July 2024, hemoperfusion was performed for 4 hours with either a sham or polymer column. Blood was collected at 5 time points over a 72-hour...
Tolnai C, O'Sullivan C, Lőrincz M, Karvouni M, Tenk M, Marosi A, Forgách P, Paszerbovics B, Wagenhoffer Z, Kutasi O.West Nile virus (WNV) is a mosquito-borne neurotropic virus that causes neurologic disease in both humans and horses. Yet the long-term cellular immune response following natural infection in horses remains poorly understood. This study aims to evaluate the WNV-specific T-cell response in horses recovered from West Nile neuroinvasive disease (WNND). Twelve client-owned horses (4 Hungarian sport horses, 2 Lippizaners, 1 KWPN, 1 Shagya Arabian, 1 Friesian, 1 Gidran, 1 Andalusian, and 1 draft cross horse) with confirmed clinical WNV infection were enrolled, and peripheral blood mononuclear cells ...
Salem MA, El-Gameel SM, Kamel MS, Elsamman EM, Ramadan RM.Equine habronemiasis, caused by Habronema (H.) muscae, H. microstoma, and Draschia megastoma, is a parasitic disease that presents in both gastric and cutaneous forms. Conventional diagnostic methods often lack sensitivity due to intermittent egg shedding and nonspecific clinical signs. This study aimed to enhance diagnostic accuracy by integrating molecular identification, oxidative stress profiling, and cytokine gene expression analysis. Methods: A total of 100 horses from a private farm in Giza, Egypt, were clinically examined for signs of habronemiasis. Fecal and skin samples were exami...
Kyari F, Pogu CJ, Mairiga IA, Adamu L.Nematode infections are a significant health concern in horses, causing a range of clinical signs and economic losses. Early detection and diagnosis are crucial for effective treatment and management. Unassigned: Examining the application of the systemic immune Inflammatory index (SII) as a predictor for nematode infections in horses, using platelets count, leucocytes count, and neutrophils count. Unassigned: A cross-sectional study was conducted on 164 horses, consisting of 66 horses with nematode infections and 98 horses without infections. The SII was computed using the platelets count, leu...
Khaliji E, Marycz K, Horna M, Morgan JM, Galuppo LD, Vapniarsky N, Cassano JM.To evaluate IA autologous platelet-derived mitochondrial preparation versus vehicle control in a bilateral lipopolysaccharide (LPS)-induced model of equine synovitis. Unassigned: 2 ng of LPS was injected into bilateral intercarpal joints of 6 horses over 3 months. Autologous mitochondria, isolated with a commercial kit, were injected into one joint, while the contralateral joint received a vehicle control, a within-subject controlled experimental design. Mitochondrial organelle appearance was visualized on transmission electron microscopy. Outcome measures included synovial fluid and whole-blo...
Roncaglia-Pereira VA, Dumard CH, Monteiro-Machado M, Melo PA, Fonseca J, Meirelles L, Cunha-Ribeiro L, Souza P, da Silva JL, Castilho L....In this study, we aim to report the persistent presence of anti-SARS-CoV-2 immunoglobulins in pre-immunized mare offspring. Three mares from Vital Brazil Institute were pre-immunized with recombinant SARS-CoV-2 spike protein and became pregnant during this period. After parturition, the mares' serum and colostrum/milk and foal serum were collected over 6 weeks. Our results have shown high and persistent presence of IgG and neutralizing antibodies over the weeks not only in the mares' serum, as expected, but in mares' colostrum/milk and foal serum as well-what were very surprising. This peculia...
Migliorisi A, Hassel DM, Moore AR, Blair BW, Wilkins PA.To characterize coagulopathies before and after antivenom administration in rattlesnake-envenomated equids. Unassigned: Client-owned envenomated equids treated with antivenom at Colorado State University (2023 to 2024). Rattlesnake bite severity score (RBSS), platelet count, prothrombin time, activated thromboplastin time, D-dimers, antithrombin, and viscoelastic testing variables were assessed before and after antivenom administration. Paired comparisons of hemostatic variables between admission and approximately 24 hours, and correlation analysis with RBSS, were performed. Length of hospital...
Hildebrandt D, Venner M, Hart KA, Berghaus L.Early and specific diagnosis of bronchopneumonia in foals is important to prevent severe disease. In human medicine, C-reactive protein (CRP) and interleukin-6 (IL-6) are important diagnostic and prognostic biomarkers in neonatal pneumonia in other species. Evaluation of these markers in foals with naturally occurring respiratory diseases is lacking. Objective: To determine if CRP and IL-6 were useful predictors of respiratory disease in foals from birth to weaning. Methods: Prospective cohort study. Methods: Periodic blood samples from 200 initially healthy foals were collected from birth to ...
Mohamed E, Van Cleemput J, Şahin B, Van den Broeck W, Boyen F, Nauwynck H.The equine respiratory and reproductive tract microbiomes are complex and subject to constant fluctuations. Among the microbial inhabitants, subsp. (SEZ) is recognized as the dominant bacterium. It is an opportunistic pathogen that may occasionally lead to various types of infections. A key virulence factor of SEZ is the streptolysin S (SLS) toxin, which is responsible for the characteristic β-hemolysis on blood agar and tissue damage. Viruses and bacteria may interact and aggravate lesions and disease. This study aimed to evaluate the impact of an SLS-containing supernatant from SEZ on the...
Albornoz A, Morales B, Fernandez VB, Henriquez C, Quiroga J, Alarcón P, Moran G, Burgos RA.Equine asthma is a chronic respiratory disease characterised by neutrophilic inflammation, airway hyperresponsiveness, and impaired pulmonary function. Obesity, increasingly prevalent among domestic horses, has been identified as a potential risk factor for exacerbating inflammatory conditions. This study aimed to explore whether obesity modifies neutrophil metabolism and inflammatory responses in horses affected by asthma. Six asthmatic horses in clinical remission were categorised into two groups: obese and non-obese, based on body condition score. Serum levels of interleukin-1β (IL-1β) an...
Perkins GA, Wagner B, Rollins A, Sfraga H, Pearson E, Cercone M.To apply equine herpesvirus type 1 (EHV-1) antibody testing in nasal swabs and serum in nonclinical horses during a naturally occurring outbreak of (EHV-1). Previous experimental EHV-1 challenge studies showed stable serum anti-EHV-1 antibody concentrations paired with rapidly increasing nasal mucosal antibodies (mucAbs) prevent EHV-1 infection, viral shedding, and cell-associated viremia. From this, we hypothesized that EHV-1 antibody testing can confirm exposure in non-clinical horses during an outbreak. Unassigned: 2 horses with neurological signs from 1 farm were admitted to an equine hosp...
Neudeck S, Sauter PK, Kutter APN, Steblaj B, Söbbeler FJ, Reiners J, Freise F, Gutiérrez Bautitsta AJ, Kästner SBR.Endotoxaemia is a significant cause of morbidity and mortality in equids due to perfusion impairment and possible destruction of the glycocalyx. To evaluate our hypothesis that endotoxaemia induces changes in global cardiovascular and haematologic parameters and compromises glycocalyx integrity, evidenced by an early rise in plasma shedding products. In vivo experiments METHODS: In a prospective, randomised, controlled experimental trial, endotoxaemia was induced with E. coli B55:O5 LPS 30 ng kg over 30 min IV in six healthy adult horses ventilated with oxygen supplemented with isoflurane. St...
Tolnai CH, Forgách P, Marosi A, Fehér O, Paszerbovics B, Tenk M, Wagenhoffer Z, Kutasi O.In the last three decades, West Nile virus (WNV, Flaviviridae, Orthoflavivirus genus) has become one of the most important encephalitic agents worldwide, causing substantial numbers of cases in humans and horses every year by re-emerging in endemic areas and emerging in new territories. It is considered that after natural WNV infection, humans and birds develop long-term immunoprotection, but data on immunoprotection in horses is scarce. Objective: West Nile virus infection provides long-term humoral immunity in subclinically infected horses. Methods: Client-owned, naturally WNV subclinically ...
Berni P, Del Bue M, Conti V, Andreoli V, Ramoni R, Angelone M, Squassino GP, Bari E, Torre ML, Rinaldi M, Dotti S, Rossi R, Yusuf I, Mauri P....Most in vivo studies on MSC-secretome for osteoarthritis (OA) have relied on animal models, using products lacking pharmaceutical quality, not formulated for clinical use, and insufficiently characterized, limiting knowledge of its effectiveness. This study reports veterinary clinical trials on dogs and horses with spontaneous OA: in dogs (26 subjects), the trial is randomized, double-blinded, and controlled; in horses, 5 clinical cases were treated for safety assessment. Treatment consisted of hyaluronic acid with either lyosecretome - a freeze-dried, injectable MSC-secretome obtained through...
Bannai H, Kambayashi Y, Kume K, Takebe N, Endo Y, Kawanishi N, Nemoto M, Tsujimura K.The endemic situation of respiratory disease caused by equine herpesvirus type-1 (EHV-1) and type-4 (EHV-4) was investigated in a training facility for Thoroughbred yearlings in Japan. Vaccination typically starts in mid-September or early October-only after all yearlings have arrived-leaving those introduced earlier unprotected. To bridge this immunity gap, a revised vaccination program that started earlier was implemented. In 2021-2022 and 2022-2023, yearlings were allocated to three groups according to their introduction dates. Each group received a live EHV-1 vaccine (Equi N Tect ERP, Niss...
Jonsdottir S, Stefansdottir SB, Mirkovitch J, Ziegler A, Torsteinsdottir S, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis in horses caused by bites of spp. The allergens are salivary gland proteins from these insects, and nine major allergens from have been identified and expressed in . However, proteins expressed in procaryotic systems have limitations in cellular assays, particularly in functional assays assessing the allergen-induced release of mediators , such as sulphidoleukotrienes (sLT) from basophils. The aims of the study were to produce functional allergens in insect cells, to assess their allergenicity using a sLT release assay, and to...
Cserhalmi D, Wermer K.Our paper presents a case study of a Welsh pony mare with grazing-induced severe urticaria. The main clinical signs were eye swelling, depression and extensive urticaria. Physical examination revealed no other abnormalities. Botanical sampling revealed horseweed (Conyza canadensis) as the most abundant species and a potential allergen plant due to sesquiterpene lactones (SQL). Differential diagnosis strongly suggested that the clinical signs were the result of a hypersensitivity reaction to this plant. Former studies brought controversial data about the toxic or allergic potential of horsewee...
Smith T.The foregoing and earlier data taken together demonstrate that an active immunity lasting several years can be produced in guinea-pigs, by the injection of toxin-antitoxin mixtures which have no recognizable harmful effect either immediate or remote. They also show, what might have been anticipated, that under the same conditions mixtures which produce local lesions and which, therefore, contain an excess of toxin produce a much higher degree of immunity than the neutral mixtures, and that an excess of antitoxin reduces the possibility of producing an active immunity, and may extinguish it alt...
Crisman MV, Scarratt WK, Zimmerman KL.Activation of the host response to infection, the "acute-phase response," is a highly organized physiologic reaction that includes changes in concentrations of plasma acute-phase proteins (APPs). The APPs are increasingly being used as markers for prognosis and monitoring response to therapy along with general determinants of equine health. Use of APPs in veterinary medicine is becoming more widespread as more commercial diagnostic kits are being validated. This article reviews the salient features of APPs and examines their current application and potential utility in equine inflammatory diso...
Capomaccio S, Vitulo N, Verini-Supplizi A, Barcaccia G, Albiero A, D'Angelo M, Campagna D, Valle G, Felicetti M, Silvestrelli M, Cappelli K.The horse is an optimal model organism for studying the genomic response to exercise-induced stress, due to its natural aptitude for athletic performance and the relative homogeneity of its genetic and environmental backgrounds. Here, we applied RNA-sequencing analysis through the use of SOLiD technology in an experimental framework centered on exercise-induced stress during endurance races in equine athletes. We monitored the transcriptional landscape by comparing gene expression levels between animals at rest and after competition. Overall, we observed a shift from coding to non-coding regio...
Ball JM, Rushlow KE, Issel CJ, Montelaro RC.We describe here a detailed analysis of the antigenic determinants of the surface unit glycoprotein (gp90) of equine infectious anemia virus (EIAV), using a comprehensive panel of synthetic peptides in enzyme-linked immunosorbent assays with immune serum from naturally and experimentally infected horses and with a panel of gp90-specific neutralizing and nonneutralizing monoclonal antibodies. The results of these studies identify immunoreactive segments throughout the conserved and variable domains of gp90 but localize immunodominant (100% reactivity) determinants to the amino and carboxyl term...
Christoffersen M, Woodward E, Bojesen AM, Jacobsen S, Petersen MR, Troedsson MH, Lehn-Jensen H.The objective of the study was to evaluate the gene expression of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, tumor necrosis factor [TNF]-α, IL-1 receptor antagonist [ra] and serum amyloid A (SAA) in endometrial tissue and circulating leukocytes in response to uterine inoculation of 105 colony forming units (CFU) Escherichia coli in mares. Before inoculation, mares were classified as resistant or susceptible to persistent endometritis based on their uterine inflammatory response to infusion of 109 killed spermatozoa and histological assessment of the endometrial quality. ...
Chang MH, Kim KH, Kim HS, Jun HJ, Kim DH, Jang JH, Kim K, Jung CW.Immunosuppressive therapy (IST) with antithymocyte globulin (ATG) plus cyclosporine (CSA) is standard therapy in patients with severe aplastic anemia (SAA) who do not have an available HLA-matched sibling donor. Methods: The current study aimed to determine the predictive factors for response to IST in patients with SAA and to identify prognostic factors following IST. A total of 62 patients diagnosed with SAA who received IST with either rabbit ATG (n = 33) or horse ATG (n = 29) plus CSA between October 1994 and December 2007 were included. Results: With a median follow-up duration of 60.5 mo...
Reed SM, Furr M, Howe DK, Johnson AL, MacKay RJ, Morrow JK, Pusterla N, Witonsky S.Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite-specific factors...
Carpenter S, Evans LH, Sevoian M, Chesebro B.Equine infectious anemia virus was isolated from peripheral blood leukocytes collected during two early febrile cycles of an experimentally infected horse. RNase T1-resistant oligonucleotide fingerprint analyses indicated that the nucleotide sequences of the isolates differed by approximately 0.25% and that the differences appeared randomly distributed throughout the genome. Serum collected in the interval between virus isolations was able to distinguish the isolates by membrane immunofluorescence on live cells. However, no neutralizing antibody was detected in the interval between virus isola...
Perkins GA, Wagner B.The development of equine immunity from the fetus to adulthood is complex. The foal's immune response and the immune mechanisms that they are equipped with, along with changes over the first months of life until the immune system becomes adult-like, are only partially understood. While several innate immune responses seem to be fully functional from birth, the onset of adaptive immune response is delayed. For some adaptive immune parameters, such as immunoglobin (Ig)G1, IgG3, IgG5 and IgA antibodies, the immune response starts before or at birth and matures within 3 months of life. Other antib...
Hammond SA, Li F, McKeon BM, Cook SJ, Issel CJ, Montelaro RC.Persistent infection of equids by equine infectious anemia virus (EIAV) is typically characterized by a progression during the first year postinfection from chronic disease with recurring disease cycles to a long-term asymptomatic infection that is maintained indefinitely. The goal of the current study was to perform a comprehensive longitudinal analysis of the course of virus infection and development of host immunity in experimentally infected horses as they progressed from chronic disease to long-term inapparent carriage. We previously described the evolution of EIAV genomic quasispecies (C...
Morein B, Blomqvist G, Hu K.The maintenance of pregnancy requires suppression of the maternal immune system which would naturally recognize the developing fetus as an allograft and seek to destroy it by mounting a Th1 regulated cytotoxic immune response. During pregnancy a range of soluble factors are produced by the placenta which switch maternal immune regulation towards a protective Th2 phenotype. These factors also influence the developing fetal immune system and all newborns initially have an immunological milieu skewed towards Th2 immunity. Vaccination during the neonatal period must therefore overcome the dual cha...
Bonilla E, Valero-Fuenmayor N, Pons H, Chacín-Bonilla L.We investigated whether the administration of melatonin (MLT) reduces the death rate and evolution of the disease in mice infected with Venezuelan equine encephalomyelitis (VEE) virus. Our results show that, MLT protects mice infected with the virus. The mortality rate was reduced from 100% to 16% merely by increasing the dose from 0 to 1000 micrograms/MLT per kg body weight MLT significantly postponed the onset of the disease and death by several days. In surviving mice very high titres of VEE virus IgM antibodies were found seven weeks after virus inoculation. MLT significantly reduced VEE v...
Yin X, Hu Z, Gu Q, Wu X, Zheng YH, Wei P, Wang X.Human tetherin is a host restriction factor that inhibits replication of enveloped viruses by blocking viral release. Tetherin has an unusual topology that includes an N-terminal cytoplasmic tail, a single transmembrane domain, an extracellular domain, and a C-terminal glycosylphosphatidylinositol anchor. Tetherin is not well conserved across species, so it inhibits viral replication in a species-specific manner. Thus, studies of tetherin activities from different species provide an important tool for understanding its antiviral mechanism. Here, we report cloning of equine tetherin and charact...
Barlough JE, Madigan JE, DeRock E, Dumler JS, Bakken JS.A Thoroughbred filly that developed clinical signs of equine granulocytic ehrlichiosis following inoculation with the human granulocytotropic ehrlichia was shown to be resistant to challenge with Ehrlichia equi, a closely related agent. This result further substantiates the close and potentially conspecific relationship between these two granulocytotropic ehrlichiae.
Herteman N, Vargas A, Lavoie JP.Low-density neutrophils (LDNs) are a subset of neutrophils first described in the bloodstream upon pathological conditions, and recently, in the blood of healthy humans. LDNs may have an enhanced pro-inflammatory (low-density granulocytes, LDGs) or an immunosuppressive (Granulocytic myeloid-derived suppressor cells, G-MDSCs) profile. Whether these characteristics are specific to LDNs or related to disease states is unknown. Thus, we sought to investigate the properties of LDNs in both health and disease states, and to compare them to those of autologous normal-density neutrophils (NDNs). We st...
Murcia PR, Baillie GJ, Stack JC, Jervis C, Elton D, Mumford JA, Daly J, Kellam P, Grenfell BT, Holmes EC, Wood JL.Influenza A viruses are characterized by their ability to evade host immunity, even in vaccinated individuals. To determine how prior immunity shapes viral diversity in vivo, we studied the intra- and interhost evolution of equine influenza virus in vaccinated horses. Although the level and structure of genetic diversity were similar to those in naïve horses, intrahost bottlenecks may be more stringent in vaccinated animals, and mutations shared among horses often fall close to putative antigenic sites.
Woodward EM, Christoffersen M, Campos J, Betancourt A, Horohov D, Scoggin KE, Squires EL, Troedsson MH.Transient endometritis after breeding is necessary for clearance of bacteria and spermatozoa; however, in a subpopulation of mares, the inflammation fails to resolve in a timely fashion. The objective of this study was to describe the uterine inflammatory response in mares susceptible or resistant to persistent breeding-induced endometritis (PBIE) during the first 24 h after induction of uterine inflammation.Twelve mares were classified as susceptible (nZ6) or resistant (nZ6) to PBIE. Mares were inseminated over five estrous cycles and endometrial biopsies were collected at one time point per ...
Balasuriya UB, MacLachlan NJ.The members of the family Arteriviridae, genus Arterivirus, include equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), lactate dehydrogenase-elevating virus (LDV) of mice, and simian hemorrhagic fever virus (SHFV). PRRSV is the newest member of the family (first isolated in North America and Europe in the early 1990s), whereas the other three viruses were recognized earlier (EAV in 1953, LDV in 1960, and SHFV in 1964). Although arterivirus infections are strictly species-specific, the causative agents share many biological and molecular properties, inclu...
Balasuriya UB, Heidner HW, Davis NL, Wagner HM, Hullinger PJ, Hedges JF, Williams JC, Johnston RE, David Wilson W, Liu IK, James MacLachlan N.Replicon particles derived from a vaccine strain of Venezuelan equine encephalitis (VEE) virus were used as vectors for expression in vivo of the major envelope proteins (G(L) and M) of equine arteritis virus (EAV), both individually and in heterodimer form (G(L)/M). The immunogenicity of the different replicons was evaluated in horses, as was their ability to protectively immunize horses against intranasal and intrauterine challenge with a virulent strain of EAV (EAV KY84). Horses immunized with replicons that express both the G(L) and M proteins in heterodimer form developed neutralizing ant...
Alberca B, Bachanek-Bankowska K, Cabana M, Calvo-Pinilla E, Viaplana E, Frost L, Gubbins S, Urniza A, Mertens P, Castillo-Olivares J.African horse sickness virus (AHSV) is an arthropod-borne pathogen that infects all species of equidae and causes high mortality in horses. Previously, a recombinant modified vaccinia Ankara (MVA) virus expressing the protein VP2 of AHSV serotype 4 was shown to induce virus neutralising antibodies in horses and protected interferon alpha receptor gene knock-out mice (IFNAR -/-) against virulent AHSV challenge. This study builds on the previous work, examining the protective efficacy of MVA-VP2 vaccination in the natural host of AHSV infection. A study group of 4 horses was vaccinated twice wit...
Debrue M, Hamilton E, Joubert P, Lajoie-Kadoch S, Lavoie JP.Recent finding suggests that T-cells may be involved in the pathogenesis of heaves in horses. However, little is known concerning their possible contribution to pulmonary neutrophilia, a characteristic finding in heaves. Interleukin (IL)-17 is a cytokine secreted by activated T-cells that indirectly promotes the maturation, chemotaxis and activation of neutrophils. We therefore hypothesized that IL-17 may be involved in the recruitment of neutrophils into the airways and that its mRNA expression would be increased in bronchoalveolar lavage (BAL) cells of horses with heaves. Heaves susceptible ...
Villalta M, Pla D, Yang SL, Sanz L, Segura A, Vargas M, Chen PY, Herrera M, Estrada R, Cheng YF, Lee CD, Cerdas M, Chiang JR, Angulo Y, León G....The proteomes of the venoms of the snakes Viridovipera stejnegeri and Protobothrops mucrosquamatus from Taiwan were characterized by N-terminal sequencing, MALDI-TOF mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of in-gel generated tryptic peptides. Proteins belonging to the following toxin classes were identified: metalloproteinase, phospholipase A(2) (PLA(2)), serine proteinase, C-type lectin-like, CRISP, l-amino acid oxidase, disintegrin, and peptides (vasoactive and inhibitors of SVMPs). Nine horses were immunized with a mixture of these venoms. All horse...
Harrington DJ, Sutcliffe IC, Chanter N.Streptococcus equi is the aetiological agent of strangles, one of the most prevalent diseases of the horse. The animal suffering and economic burden associated with this disease necessitate effective treatment. Current antibiotic therapy is often ineffective and thus recent attention has focused on vaccine development. A systematic understanding of S. equi virulence, leading to the identification of targets to which protective immunity can be directed, is a prerequisite of the development of such a vaccine. Here, the virulence factors of S. equi are reviewed.
Tiyawisutsri R, Holden MT, Tumapa S, Rengpipat S, Clarke SR, Foster SJ, Nierman WC, Day NP, Peacock SJ.The bacterial biothreat agents Burkholderia mallei and Burkholderia pseudomallei are the cause of glanders and melioidosis, respectively. Genomic and epidemiological studies have shown that B. mallei is a recently emerged, host restricted clone of B. pseudomallei. Results: Using bacteriophage-mediated immunoscreening we identified genes expressed in vivo during experimental equine glanders infection. A family of immunodominant antigens were identified that share protein domain architectures with hemagglutinins and invasins. These have been designated Burkholderia Hep_Hag autotransporter (BuHA)...
Künzle F, Gerber V, Van Der Haegen A, Wampfler B, Straub R, Marti E.Recurrent airway obstruction (RAO) is a common condition in stabled horses characterized by small airway inflammation, airway neutrophilia and obstruction following exposure of susceptible horses to mouldy hay and straw and is thus regarded as a hypersensitivity reaction to mould spores. However, the role of immunoglobulin E antibodies (IgE) in the pathogenesis of RAO is unclear. We hypothesized that the number of cells with receptor-bound IgE in bronchoalveolar lavage fluid (BALF) and IgE levels in serum would be higher in RAO-affected than in healthy horses living in the same environment. Th...
Troedsson MH, Loset K, Alghamdi AM, Dahms B, Crabo BG.Insemination of mares with bacteria-free equine spermatozoa results in an influx of polymorphonuclear neutrophils (PMNs) into the uterine lumen. In vitro studies have demonstrated that equine spermatozoa activate complement, resulting in cleavage of factors C5a and C3b. Since uterine secretion is rich in complement, it is likely that an interaction between spermatozoa and uterine secretion results in C5a-mediated chemotaxis and migration of PMNs into the uterine lumen. Once in the uterine lumen, the PMNs phagocytize bacteria and spermatozoa, which is an important part of sperm elimination from...
Dunnett M, Harris RC.The aim of this work was to test the hypothesis that in vivo carnosine biosynthesis is dependent upon endogenous beta-alanine availability, by studying the effect of sustained dietary beta-alanine supplementation in the horse on the carnosine concentration in types I, IIA and IIB skeletal muscle fibres. The diets of 6 Thoroughbred horses were supplemented 3 times/day with beta-alanine (100 mg/kg bwt) and L-histidine (12.5 mg/kg bwt) for a period of 30 days. Percutaneous biopsies of the m. gluteus medius from a depth of 6 cm were taken on the days immediately before and after the supplementatio...
Pfaender S, Walter S, Grabski E, Todt D, Bruening J, Romero-Brey I, Gather T, Brown RJ, Hahn K, Puff C, Pfankuche VM, Hansmann F, Postel A, Becher P....Hepatitis C virus (HCV) displays a restricted host species tropism and only humans and chimpanzees are susceptible to infection. A robust immunocompetent animal model is still lacking, hampering mechanistic analysis of virus pathogenesis, immune control, and prophylactic vaccine development. The closest homolog of HCV is the equine nonprimate hepacivirus (NPHV), which shares similar features with HCV and thus represents an animal model to study hepacivirus infections in their natural hosts. We aimed to dissect equine immune responses after experimental NPHV infection and conducted challenge ex...
Berglund AK, Fisher MB, Cameron KA, Poole EJ, Schnabel LV.Allogeneic mesenchymal stem cells (MSCs) are a promising cell source for treating musculoskeletal injuries in horses. Effective and safe allogeneic therapy may be hindered, however, by recipient immune recognition and rejection of major histocompatibility complex (MHC)-mismatched MSCs. Development of strategies to prevent immune rejection of MHC-mismatched MSCs in vivo is necessary to enhance cell survival and potentially increase the efficacy and safety of allogeneic MSC therapy. The purposes of this study were to evaluate if transforming growth factor-β2 (TGF-β2) downregulated MHC expressi...
