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.
Hu B, Gao S, Zhang H, Li Q, Li G, Zhang S, Xing Y, Huang Y, Han S, Tian Y, Zhang W, He H.Rhodococcus equi (R. equi) is a Gram-positive zoonotic pathogen that frequently leads to illness and death in young horses (foals). This study presents the complete genome sequence of R. equi strain BJ13, which was isolated from a thoroughbred racehorse breeding farm in Beijing, China. Results: The BJ13 genome has a length of 5.30 Mb and consists of a complete chromosome and a plasmid measuring 5.22 Mb and 0.08 Mb, respectively. We predicted 4,929 coding gene open reading frames, along with 52 tRNAs and 12 rRNAs. Through analysis of mobile genetic elements, we identified 6 gene islands and ...
Stevanović J, Glavinić U, Ristanić M, Erjavec V, Denk B, Dolašević S, Stanimirović Z.This review aims to present current knowledge on the effects of honey bee products on animals based on in vivo studies, focusing on their application in clinical veterinary practice. Honey's best-proven effectiveness is in treating wounds, including those infected with antibiotic-resistant microorganisms, as evidenced in horses, cats, dogs, mice, and rats. Propolis manifested a healing effect in numerous inflammatory and painful conditions in mice, rats, dogs, and pigs and also helped in oncological cases in mice and rats. Bee venom is best known for its effectiveness in treating neuropathy an...
Woodrow JS, Palmisano M, Kulp J, Hopster K.Complications from general anesthesia, including pneumonia and decreased wound healing, are influenced by changes in immune cell function secondary to sedatives and anesthetics. It was hypothesized that immune cell function would be depressed in the early postanesthetic period. The objective was to investigate airway immune cell function before and after a general anesthetic episode in an equine in vivo model using ex vivo cell stimulations with lipopolysaccharide (LPS) for assessment of immune function. Methods: Prospective experimental study. Methods: Six healthy, adult, institution-owned ...
Yaneselli K, Ávila G, Rossi A, Rial A, Castro S, Estradé MJ, Suárez G, Algorta A.Platelet lysate (PL) is investigated as a potential replacement for fetal bovine serum (FBS) in cell culture. However, there is limited research on its impact on the immune profile of equine mesenchymal stromal cells (eMSCs). This study aimed to evaluate the effects of different PL formulations on the proliferative capacity, multipotentiality, and immune profile of equine adipose tissue-derived MSCs (eAD-MSCs). growth kinetics and trilineage differentiation of eAD-MSCs ( = 7) were assessed under three culture conditions: medium-concentration PL (MPL), high-concentration PL (HPL), and FBS ...
Bourebaba L, Bourebaba N, Galuppo L, Marycz K.Nowadays, regenerative medicine techniques are usually based on the application of mesenchymal stem cells (MSCs) for the repair or restoration of injured damaged tissues. However, the effectiveness of autologous therapy is limited as therapeutic potential of MSCs declines due to patient's age, health condition and prolonged in vitro cultivation as a result of decreased growth rate. For that reason, there is an urgent need to develop strategies enabling the in vitro rejuvenation of MSCs prior transplantation in order to enhance their in vivo therapeutic efficiency. In presented study, we attemp...
Ringo RS, Choonnasard A, Okabayashi T, Saito A. can establish persistent infections in animals such as equids, pigs, nonhuman primates, rodents, and possums. Some can even cause overt and severe diseases such as Equine Arteritis in horses and Porcine Reproductive and Respiratory Syndrome in pigs, leading to huge economic losses. have evolved viral proteins to antagonize the host cell's innate immune responses by inhibiting type I interferon (IFN) signaling, assisting viral evasion and persistent infection. So far, the role of the glycoprotein 5 (GP5) protein in IFN signaling inhibition remains unclear. Here, we investigated the inhibito...
Feijo LS, Wolfsdorf KE, Canisso IF, Parry S, Felippe MJB.Placental infection is an important cause of late-term pregnancy loss and neonatal diseases in horses. Detection of changes in blood parameters especially during early placentitis could improve the diagnostic accuracy, treatment decision, and potential outcomes. The objectives of this 2-part study were to identify differences in circulating immunological, inflammatory, and hormonal parameters between mares with natural ascending placentitis and control mares; evaluate each and combination of parameters as predictors of placentitis; and determine how these parameters indicate severity of placen...
Fedorka CE, Scoggin KE, El-Sheikh Ali H, Troedsson MHT.The interleukin (IL)-6 family of cytokines is grouped by a common receptor subunit (gp130), but functions in distinct but overlapping physiological activities, including regulation of acute phase reaction and the balance between effector and regulatory T cell populations-both of which play a role in successful pregnancy maturation. Methods: Here, we aim to assess the expression profiles of members of the IL-6 cytokine family throughout equine gestation. To do so, RNA Sequencing was performed on chorioallantois and endometrium of mares at 120, 180, 300, and 330 days of gestation (n = 4/stage), ...
Giercuszkiewicz-Hecold B, Kulka M, Czopowicz M, Szarska E, Strzelec K, Grzeczka A, Graczyk S, Wiśniewska M, Jędrzejkowska Z, Rumińska A, Marycz K....This study aimed to evaluate the oral supplementation of astaxanthin (ATX) on inflammatory markers in 3-year-old Arabian racehorses. Despite the recognized antioxidant and anti-inflammatory properties of ATX observed in vitro in rodent models and in human athletes, the effects in equine subjects remain unknown. This study involved a controlled trial with 14 horses receiving either ATX (six horses) or a placebo (eight horses), monitored over four months of race training. Inflammatory cytokines: TNFα, IFNγ, IL-6, IL-10, and prostaglandin E (PGE), were measured monthly to assess the impact of A...
Calomeno SS, Freitas Santi T, Barbosa B, Weber SH, Oliveira TM, Machado GF, Michelotto PV.Horses maintained outdoors may experience a lower-allergenic environment compared to their stabled counterparts. This study hypothesizes that climatic changes in southern Brazil can influence respiratory status. To test this hypothesis, we evaluated the lower airways of 17 horses from a teaching herd in southern Brazil, maintained outdoors, during winter, spring, and summer. Except for one mare with a history of severe asthma, all horses were considered healthy and underwent a physical examination. Airway endoscopic evaluation included scoring for tracheal mucus (0-5) and bronchial septum thic...
Byron M, Lection J, Foster RA, Chenier T, Wagner B, Diel de Amorim M.Prostaglandins have many roles in the equine reproductive tract, including but not limited to luteolysis, luteal support, ovulation, transport through the uterine tube, uterine contraction, embryonic mobility, inflammation, and fibrosis. Altered secretion of inflammatory proteins are likely to disrupt the balance of endometrial function and could impair fertility. Our overall goal was to measure the expression of several prostaglandin- and inflammation-related genes in mares with different degrees of endometrial histological changes. Our hypothesis was that mares with neutrophilic and lymphocy...
Yoshida S, Matsuda A, Iwata E, Ono T, Hisaeda K, Ohzawa E, Hiasa Y, Kitagawa H.Noma horses are native Japanese horses. Health checkups revealed that many Noma horses developed dermatitis during summer, which subsided in winter. Seasonal development and signs of itching, suggestive of allergic dermatitis, were observed. In this study, allergen-specific IgE was measured using blood samples collected from 15 Noma horses in summer and winter to identify allergens highly associated with dermatitis. The presence of dermatitis in the subject individuals was recorded during blood sample collection. White blood cell and eosinophil counts, serum total IgE concentration, and serum ...
Jebbawi F, Chemnitzer A, Dietrich M, Pantelyushin S, Lam J, Rhiner T, Keller G, Waldern N, Canonica F, Fettelschoss-Gabriel A.Insect bite hypersensitivity (IBH) is the most frequent skin allergy of horses and is highly debilitating, especially in the chronic phase. IBH is caused by IgE-mediated hypersensitivity reactions to culicoides midge bites and an imbalanced immune response that reduces the welfare of affected horses. Unassigned: In the present study, we investigated the pathological mechanisms of IBH, aiming to understand the immune cell modulation in acute allergic skin lesions of IBH horses with the goal of finding possible biomarkers for a diagnostic approach to monitor treatment success. Unassigned: By qPC...
Pihl TH, Engelhart KE, Houen G.Polyclonal antibodies are relatively easy to produce and may supplement monoclonal antibodies for some applications or even have some advantages.The choice of species for production of (peptide) antisera is based on practical considerations, including availability of immunogen (vaccine) and animals. Two major factors govern the production of antisera: the nature of adaptive immune responses, which take place over days/weeks and ethical guidelines for animal welfare.Here, simple procedures for immunization of mice, rabbits, sheep, goats, pigs, horses, and chickens are presented.
Arrigo F, Aragona F, Faggio C, Giudice E, Giannetto C, Piccione G, Rizzo M, Arfuso F.The aim of this study was to assess the changes of pro-inflammatory interleukins in 10 horses subjected to road transport practices (distance of 150 km) from the training site (Messina, Sicily) to the competition centre in Syracuse (Sicily). Blood sampling and interleukins analysis were performed during a round trip transportation (transport 1 and transport 2). In particular, blood samples were collected before the transport took place (Pre), five minutes later (Post) and one hour later (Post 1 h), for each transport, in order to assess the serum concentration of IL-1α, IL-1β, IL-2 and IL-...
Ramadan RM, Taha NM, Auda HM, Elsamman EM, El-Bahy MM, Salem MA.Equine piroplasmosis is not fully understood regarding pathogenicity, prophylaxis, host immune response expression, and specific vectors. Accurately identifying the parasite vector is crucial for developing an effective control plan for a particular infection. This study focused on morphologically identifying two Hyalomma species (H. anatolicum and H. marginatum) and one Rhipicephalus annulatus (R. annulatus) at the species level. The identification process was followed by phylogenetic analysis using the neighbor-joining method based on the cytochrome oxidase subunit 1 (COXI) gene as a specifi...
Babasyan S, Rollins A, Wagner B.Interleukin-1β (IL-1β) is one of the key mediators of inflammation during innate immune responses. Mature bioactive IL-1β mediates essential host defense mechanisms but also has a mechanistic role in several autoinflammatory and degenerative diseases. In horses, specific and sensitive assays for IL-1β are crucial for immunological research on inflammatory processes and diseases. In this article, we describe the development of four monoclonal antibodies (mAbs) against equine IL-1β. The specificity of the new IL-1β mAbs was confirmed using a panel of equine recombinant cytokines and chemok...
Ryt-Hansen P, Johansen VK, Cuicani MM, Larsen LE, Hansen S.Equine herpesvirus 4 (EHV-4) causes respiratory disease in horses, and the virus is considered endemic in the global equine population. However, outbreaks can occur when several horses are gathered in relation to shows, competitions, breeding units and at hospitals. In the spring year 2022, an EHV-4 outbreak occurred at the Large Animal Teaching Hospital, University of Copenhagen, Denmark. Nine horses were tested EHV-4 positive during the outbreak, which lasted approx. seven weeks. In addition, a tenth horse "Eq10" tested EHV-4 positive almost three weeks after the last of the outbreak horses ...
Baumgarten CM, Delph Miller KM, Davis EG, Beard LA, Blevins CA, Wottowa M, Hill M, Larson RL.To measure the effect of routine vaccination on serum amyloid A (SAA) concentration in apparently healthy horses. We hypothesized that routine vaccination would increase SAA in healthy horses. Methods: 21 apparently healthy client-owned horses and 15 Kansas State University College of Veterinary Medicine-owned horses. Methods: In experiment 1 (n = 8 horses), a blinded, randomized, prospective, crossover study was performed. Horses were either vaccinated (rabies, tetanus, West Nile, Eastern and Western equine encephalomyelitis, equine herpesvirus-1/-4, influenza) or administered saline, and SAA...
Hu Y, Wu G, Jia Q, Zhang B, Sun W, Sa R, Zhang S, Cai W, Jarhen , Ran D, Liu J.Equid alphaherpesvirus 1 (EqAHV1) is a viral pathogen known to cause respiratory disease, neurologic syndromes, and abortion storms in horses. Currently, there are no vaccines that provide complete protection against EqAHV1. Marker vaccines and the differentiation of infected and vaccinated animals (DIVA) strategy are effective for preventing and controlling outbreaks but have not been used for the prevention of EqAHV1 infection. Glycoprotein 2 (gp2), located on the envelope of viruses (EqAHV1), exhibits high antigenicity and functions as a molecular marker for DIVA. In this study, a series of...
Leppänen V, Mykkänen A.Vipera berus berus is the only venomous snake present in the Nordic countries and cases of envenomation in horses are reported during the warmer months. Little is known about the presentation, treatment and survival of horses with common European adder envenomation. Clinical and laboratory findings, treatment and outcome are reported for 28 horses admitted to Helsinki University Equine Hospital in 2008-2023 due to suspicion of snake bite. Eleven of these horses received antivenom treatment. Other common treatments included non-steroidal anti-inflammatories (22/28), antimicrobials (19/28), intr...
Pimenta J, Prada J, Pires I, Cotovio M.Sarcoids and squamous cell carcinomas (SCCs) are the most concerning equine oncological diseases. Both tumors are challenging to manage due to their invasive behavior and high prevalence of recurrences. Furthermore, SCCs have a propensity to metastasize. Programed cell-death ligand 1 (PD-L1) has been one of the main therapeutic targets for immunotherapy in various human tumors. PD-L1 research in equine tumors is scarce and more efforts are necessary to understand the potential of this biomarker as a therapeutical target. Unassigned: Evaluate the immunohistochemical expression of PD-L1 in equin...
Carey KJ, Smith I, Barr J, Caruso S, Au GG, Hartley CA, Bailey KE, Perriam W, Broder CC, Gilkerson JR.Hendra virus (HeV) is lethal to horses and a zoonotic threat to humans in Australia, causing severe neurological and/or respiratory disease with high mortality. An equine vaccine has been available since 2012. Foals acquire antibodies from their dams by ingesting colostrum after parturition, therefore it is assumed that foals of mares vaccinated against HeV will have passive HeV antibodies circulating during the first several months of life until they are actively vaccinated. However, no studies have yet examined passive or active immunity against HeV in foals. Here, we investigated anti-HeV a...
Abreu MC, Conrad NL, Gonçalves VS, Leite FPL.Probiotic microorganisms can stimulate an immune response and increase the efficiency of vaccines. For example, Bacillus toyonensis is a nonpathogenic, Gram-positive bacterium that has been used as a probiotic in animal supplementation. It induces immunomodulatory effects and increases the vaccine response in several species. This study aimed to evaluate the effect of B. toyonensis supplementation on the modulation of the immune response in horses vaccinated with recombinant Clostridium tetani toxin. Twenty horses were vaccinated twice, with an interval of 21 days between doses, and equally di...
Heil BA, van Heule M, Thompson SK, Kearns TA, Beckers KF, Oberhaus EL, King G, Daels P, Dini P, Sones JL.The equine uterus is highly interrogated during estrus prior to breeding and establishing pregnancy. Many studies in mares have been performed during estrus under the influence of high estrogen concentrations, including the equine estrual microbiome. To date, it is unknown how the uterine microbiome of the mare is influenced by cyclicity; while, the equine vaginal microbiome is stable throughout the estrous cycle. We hypothesized that differences would exist between the equine endometrial microbiome of mares in estrus and anestrus. The aim of this study was two-fold: to characterize the reside...
Mönki J, Mykkänen A.Mild-moderate and severe equine asthma (MEA and SEA) are prevalent inflammatory airway conditions affecting horses of numerous breeds and disciplines. Despite extensive research, detailed disease pathophysiology and the differences between MEA and SEA are still not completely understood. Bronchoalveolar lavage fluid cytology, broadly used in clinical practice and in equine asthma research, has limited means to represent the inflammatory status in the lower airways. Lipidomics is a field of science that can be utilized in investigating cellular mechanisms and cell-to-cell interactions. Studies ...
Cequier A, Vázquez FJ, Vitoria A, Bernad E, Fuente S, Serrano MB, Zaragoza MP, Romero A, Rodellar C, Barrachina L.The effectiveness and safety of allogeneic mesenchymal stem/stromal cells (MSCs) can be affected by patient's immune recognition. Thus, MSC immunogenicity and their immunomodulatory properties are crucial aspects for therapy. Immune responses after allogeneic MSC administration have been reported in different species, including equine. Interactions of allogenic MSCs with the recipient's immune system can be influenced by factors like matching or mismatching for the major histocompatibility complex (MHC) between donor-recipient, and by the levels of MHC expression in MSCs. The latter can vary u...
Thorne PS, Perry SS, Saito R, O'Shaughnessy PT, Mehaffy J, Metwali N, Keefe T, Donham KJ, Reynolds SJ.As a potent inflammatory agent, endotoxin is a key analyte of interest for studies of lung ailments in domestic environments and occupational settings with organic dust. A relatively unexplored advance in endotoxin exposure assessment is the use of recombinant factor C (rFC) from the Limulus pathway in a fluorometric assay. In this study, we compared airborne endotoxin concentrations in laboratory- and field-collected parallel air samples using the kinetic Limulus amebocyte lysate (LAL) assay and the rFC assay. Air sampling was performed using paired Institute of Occupational Medicine (IOM) sa...
Hammond SA, Raabe ML, Issel CJ, Montelaro RC.We previously demonstrated in trials of a variety of experimental vaccines to equine infectious anemia virus (EIAV) a remarkable spectrum of efficacy ranging from sterilizing protection to severe enhancement of virus replication and disease, depending on the immunization strategy used. This range of vaccine efficacy observed in vivo offers a unique opportunity for evaluating potential in vitro immune correlates of protection and enhancement. We describe here a comprehensive analysis and comparison of EIAV envelope-specific antibody responses elicited by attenuated, inactivated whole virus and ...
Kabithe E, Hillegas J, Stokol T, Moore J, Wagner B.CD14 is a receptor for the complex of lipopolysaccaride (LPS) and LPS-binding protein. Binding of this complex to CD14 in association with Toll-like receptor 4 provides a major pathway for the initiation of innate immune responses to bacterial pathogens. We used a mammalian expressed extracellular region of equine CD14 (rCD14) derived from an IgG fusion protein to produce monoclonal antibodies (mAbs) to CD14. Eight mAbs were tested by flow cytometric analysis of equine leukocytes and by immunoblotting using rCD14 indicating that the mAbs recognized at least three different epitopes on equine C...
Rossi SL, Guerbois M, Gorchakov R, Plante KS, Forrester NL, Weaver SC.Venezuelan equine encephalitis virus (VEEV) is an arbovirus that causes periodic outbreaks that impact equine and human populations in the Americas. One of the VEEV subtypes located in Mexico and Central America (IE) has recently been recognized as an important cause of equine disease and death, and human exposure also appears to be widespread. Here, we describe the use of an Internal Ribosome Entry Site (IRES) from encephalomyocarditis virus to stably attenuate VEEV, creating a vaccine candidate independent of unstable point mutations. Mice infected with this virus produced antibodies and wer...
Soboll G, Horohov DW, Aldridge BM, Olsen CW, McGregor MW, Drape RJ, Macklin MD, Swain WF, Lunn DP.We have previously demonstrated that hemagglutinin (HA) gene vaccination and influenza virus infection generate protective antibody responses in equids. However, these antibody responses differ substantially in that particle mediated DNA vaccination does not induce an immunoglobulin A (IgA) response. A study was performed to investigate the regional immunoregulatory mechanisms associated with these different immune responses. Ponies were either vaccinated with equine HA DNA vaccines at skin and mucosal sites, infected with influenza virus or left untreated and influenza-specific antibody respo...
Lin YZ, Shen RX, Zhu ZY, Deng XL, Cao XZ, Wang XF, Ma J, Jiang CG, Zhao LP, Lv XL, Shao YM, Zhou JH.The EIAV (equine infectious anemia virus) multi-species attenuated vaccine EIAV(DLV121) successfully prevented the spread of equine infectious anemia (EIA) in China in the 1970s and provided an excellent model for the study of protective immunity to lentiviruses. In this study, we compared immune responses induced by EIAV(DLV121) to immunity elicited by the virulent EIAV(LN40) strain and correlated immune responses to protection from infection. Horses were randomly grouped and inoculated with either EIAV(DLV121) (Vaccinees, Vac) or a sublethal dose of EIAV(LN40) (asymptomatic carriers, Car). C...
Nieto JE, MacDonald MH, Braim AE, Aleman M.Horses are exquisitely sensitive to bacterial endotoxin and endotoxaemia is common in colic cases. In this study, gene expression of inflammatory cytokines was characterised in the blood of healthy horses following i.v. administration of lipopolysaccharide (LPS). Six horses received an LPS infusion and 6 controls received an equivalent volume of saline. Gene expression of genes encoding interleukin (IL)-1alpha, IL-1beta, IL-6, IL-8, and tumour necrosis factor-alpha (TNF-alpha) was quantified by real-time PCR. Gene expression of all inflammatory cytokines was upregulated following administratio...
Kasel JA, Couch RB.The recognition of an antigenic relationship between the haemagglutinins of A/Equi-2 and A2/Hong Kong/68 viruses led to experimental studies in man and horses with these virus types.Human volunteers were inoculated with A/Equi-2/Miami/63 virus and virus shedding ensued in all subjects. The most common clinical response was a febrile illness indistinguishable from naturally occurring human influenza. After administration of A2/Hong Kong/68 virus to 10 ponies there was virus shedding from 9 and a febrile response in 6.When the human subjects previously inoculated with equine virus were challenge...
Cauchard S, Bermúdez-Humarán LG, Blugeon S, Laugier C, Langella P, Cauchard J.Rhodococcus equi causes severe pneumonia in foals and has recently gained attention as a significant opportunistic pathogen in immunocompromised humans. However, no effective vaccine to prevent rhodococcosis is currently available. In this study, we have engineered the food-grade bacterium Lactococcus lactis to secrete the virulence-associated protein A from R. equi (LL-VapA). The immunogenic potential of LL-VapA strain was then evaluated after either intragastric or intranasal immunization in mice either alone or in combination with LL-Lep, a recombinant strain of L. lactis secreting biologic...
Schumacher J, Edwards JF, Cohen ND.A review of reported cases of inflammatory bowel diseases (IBDs) of horses for which no etiology was identified included cases of granulomatous enteritis (GE), multisystemic eosinophilic epitheliotropic disease (MEED), lymphocytic-plasmacytic enterocolitis (LPE), and idiopathic eosinophilic enterocolitis (EC). The terms EC and MEED were both used to describe a disease in horses characterized by infiltration of intestine and extraintestinal tissues with eosinophils. We use EC to describe IBD characterized by only intestinal infiltration by eosinophils. Horses with GE, MEED, or LPE are usually e...
Davis MS, Williams CC, Meinkoth JH, Malayer JR, Royer CM, Williamson KK, McKenzie EC.To determine effects of exercise performed while breathing cold air on expression of cytokines and influx of neutrophils in airways of horses. Methods: 9 adult horses. Methods: In a crossover study, bronchoalveolar lavage fluid (BALF) was obtained 24 and 48 hours after each of 2 submaximal exercise sessions performed by horses while breathing warm (25 degrees C) or cold (-5 degrees C) air. Total and differential nucleated cell counts were determined for each BALF sample. Relative mRNA expression of cytokines in BALF cells was quantified by use of a reverse transcription-PCR assay. Results: Hor...
Craigo JK, Leroux C, Howe L, Steckbeck JD, Cook SJ, Issel CJ, Montelaro RC.The genetic variation of equine infectious anaemia virus (EIAV) clearly affects the antigenic properties of the viral envelope; however, effects on immunogenicity remain undefined, although widely assumed. Here, the immunogenicity is reported of a novel, neutralization-resistant, pony-isolate envelope EIAV(PV564DeltaPND) that contains a 14-residue deletion in the designated principal neutralizing domain (PND) of the gp90 protein. Two ponies inoculated with a chimeric virus, EIAV(DeltaPND), containing the EIAV(PV564DeltaPND) envelope in a reference provirus strain, remained asymptomatic through...
Cappelli K, Felicetti M, Capomaccio S, Nocelli C, Silvestrelli M, Verini-Supplizi A.Athletic performance is both a stress factor and an adaptive response to exercise that may be modulated by training, reduce inflammation and help prevent disease. Studies on the endocrinology of exercise and training have demonstrated the existence of an integrated metabolic network of hormone and cytokine regulation. Subsequent molecular studies have shown that repeated bouts of exercise may establish new basal levels of gene expression at rest. The Thoroughbred horse may be a useful 'exercise model' for inter-individual comparisons between subjects with homogeneous genetic and environmental ...
Schnabel CL, Babasyan S, Rollins A, Freer H, Wimer CL, Perkins GA, Raza F, Osterrieder N, Wagner B.Equine herpesvirus type 1 (EHV-1) outbreaks continue to occur despite widely used vaccination. Therefore, development of EHV-1 vaccines providing improved immunity and protection is ongoing. Here, an open reading frame 2 deletion mutant of the neuropathogenic EHV-1 strain Ab4 (Ab4ΔORF2) was tested as a vaccine candidate. Three groups of horses ( = 8 each) were infected intranasally with Ab4ΔORF2 or the parent Ab4 virus or were kept as noninfected controls. Horses infected with Ab4ΔORF2 had reduced fever and nasal virus shedding compared to those infected with Ab4 but mounted similar ada...
Hooper-McGrevy KE, Wilkie BN, Prescott JF.The purpose of this study was to determine whether foals immunized orally from 2 days of age with virulent Rhodococcus equi developed a protective pulmonary immune response and to characterise the antibody response of the immunized foals to the virulence-associated proteins (Vaps) of the bacterium. Two groups of foals were used. One (n=4) was given live R. equi ATCC 33701 orally at 2, 7, and 14 days of age. The second group comprised three non-immunized foals age-matched to the vaccinates. At 3 weeks of age, 1 week after the final immunization, both groups were challenged intrabronchially with...
Figueiredo MD, Salter CE, Andrietti AL, Vandenplas ML, Hurley DJ, Moore JN.Quantification of gene expression using real-time reverse transcription quantitative PCR (RT-qPCR) is a reliable method to monitor cellular responses to pro-inflammatory stimuli. The main objective of this study was to validate a set of equine primer pairs that can be routinely used to monitor expression of genes that are central to inflammatory and immune responses. This paper describes the steps used to optimize and validate 29 equine primer pairs for RT-qPCR assays using SYBR Green detection. To validate these assays, monocytes were isolated from three horses and stimulated with Escherichia...
Paillot R, Robinson C, Steward K, Wright N, Jourdan T, Butcher N, Heather Z, Waller AS.Streptococcus equi is the causative agent of strangles, the most frequently diagnosed infectious disease of horses worldwide. The disease is characterized by abscessation and swelling of the lymph nodes of the head and neck, which can literally strangle the horse to death. S. equi produces four recently acquired phage-associated bacterial superantigens (sAgs; SeeH, SeeI, SeeL, and SeeM) that share homology with the mitogenic toxins of Streptococcus pyogenes. The aim of this study was to characterize the contribution of each of these S. equi sAgs to mitogenic activity in vitro and quantify the ...
Minke JM, Toulemonde CE, Coupier H, Guigal PM, Dinic S, Sindle T, Jessett D, Black L, Bublot M, Pardo MC, Audonnet JC.To determine onset and duration of immunity provided by a 2- or 3-dose series of a new canarypox-vectored recombinant vaccine for equine influenza virus (rCP-EIV vaccine) expressing the hemagglutinin genes of influenza H3N8 virus strains A/eq/Kentucky/94 and A/eq/Newmarket/2/93 in ponies. Methods: Forty-nine 1- to 3-year-old male Welsh Mountain Ponies that were seronegative for equine influenza virus. Methods: Vaccinated and control ponies were challenged with aerosolized influenza virus A/eq/Sussex/89 (H3N8), representative of the Eurasian lineage of circulating influenza viruses. In trial 1,...
Gildea S, Arkins S, Walsh C, Cullinane A.Many racing authorities, sales companies and equestrian bodies have mandatory vaccination policies for equine influenza (EI). The consequences of lack of vaccine efficacy include clinical disease, disruption to training programmes, the cancellation of equestrian events and the introduction of virus to susceptible populations. The correlation between antibody against the virus haemagglutinin and protection against influenza has been well established. The objective of this study was to compare the antibody responses of 66 unvaccinated Thoroughbred weanlings on four different stud farms, followin...
Khurelbaatar N, Krueger WS, Heil GL, Darmaa B, Ulziimaa D, Tserennorov D, Baterdene A, Anderson BD, Gray GC.Avian (AIV) and equine influenza virus (EIV) have been repeatedly shown to circulate among Mongolia's migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI). Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied w...
Folsom RW, Littlefield-Chabaud MA, French DD, Pourciau SS, Mistric L, Horohov DW.Equine influenza virus remains a major health concern for the equine industry in spite of ongoing vaccination programmes. Previous work has shown that the immune system of horses can be affected by strenuous exercise. The possible adverse consequence of exercise-induced alterations in lymphocyte responses measured in vitro was unknown. Here we demonstrate that subjecting vaccinated ponies to a 5 day strenuous exercise programme results in a significant suppression of their T cell-mediated immune response to equine influenza virus as measured by decreased lymphoproliferation and gamma interfero...
Ferraz LC, Bernardes ES, Oliveira AF, Ruas LP, Fermino ML, Soares SG, Loyola AM, Oliver C, Jamur MC, Hsu DK, Liu FT, Chammas R, Roque-Barreira MC.Galectin-3 is a beta-galactoside-binding lectin implicated in the fine-tuning of innate immunity. Rhodococcus equi, a facultative intracellular bacterium of macrophages, causes severe granulomatous bronchopneumonia in young horses and immunocompromised humans. The aim of this study is to investigate the role of galectin-3 in the innate resistance mechanism against R. equi infection. The bacterial challenge of galectin-3-deficient mice (gal3-/-) and their wild-type counterpart (gal3+/+) revealed that the LD50 for the gal3(-/-) mice was about seven times higher than that for the gal3+/+ mice. Wh...
Hines MT, Paasch KM, Alperin DC, Palmer GH, Westhoff NC, Hines SA.Rhodococcal pneumonia is an important disease of young horses that is not seen in immunocompetent adults. Since all foals are normally exposed to Rhodococcus equi in their environment, we hypothesized that most develop protective immune responses. Furthermore, these antigen-specific responses were hypothesized to operate throughout adult life to prevent rhodococcal pneumonia. A better understanding of the mechanisms of immune clearance in adult horses would help define the requirements for an effective vaccine in foals. Adult horses were challenged with virulent R. equi by intrabronchial inocu...
Holbrook TC, Tipton T, McFarlane D.Equine metabolic syndrome is characterized by obesity and regional adiposity coupled with evidence of recurrent laminitis. Although inflammation has been well characterized in several experimental models of acute laminitis, the inflammatory events associated with endocrinopathic laminitis are not well documented. The aim of this study was to characterize selected markers of inflammation in horses with clinical evidence of equine metabolic syndrome (EMS). Neutrophil phagocytosis and oxidative burst, as well as endogenous and stimulated cytokine expression were evaluated. A marked increase in ne...
Edlund Toulemonde C, Daly J, Sindle T, Guigal PM, Audonnet JC, Minke JM.Fifteen influenza-naive Welsh mountain ponies were randomly assigned to three groups of five. A single dose of a recombinant ALVAC vaccine was administered intramuscularly to five of the ponies, two doses, administered five weeks apart, were administered to five, and the other five served as unvaccinated, challenge controls. Two weeks after the completion of the vaccination programme, the ponies were all challenged by exposure to an aerosol of influenza virus A/eq/Newmarket/5/03. Their clinical signs were scored daily for 14 days according to a standardised scoring protocol, and nasal swabs we...
Howe L, Leroux C, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) infection of horses is characterized by well-defined waves of viremia associated with the sequential evolution of distinct viral populations displaying extensive envelope gp90 variation; however, a correlation of in vivo envelope evolution with in vitro serum neutralization phenotype remains undefined. Therefore, the goal of the present study was to utilize a previously defined panel of natural variant EIAV envelope isolates from sequential febrile episodes to characterize the effects of envelope variation during persistent infection on viral neutralizatio...
Go YY, Bailey E, Cook DG, Coleman SJ, Macleod JN, Chen KC, Timoney PJ, Balasuriya UB.Previously, we have shown that horses could be divided into susceptible and resistant groups based on an in vitro assay using dual-color flow cytometric analysis of CD3+ T cells infected with equine arteritis virus (EAV). Here, we demonstrate that the differences in in vitro susceptibility of equine CD3+ T lymphocytes to EAV infection have a genetic basis. To investigate the possible hereditary basis for this trait, we conducted a genome-wide association study (GWAS) to compare susceptible and resistant phenotypes. Testing of 267 DNA samples from four horse breeds that had a susceptible or a r...
Murcia RY, Vargas A, Lavoie JP.Glucocorticoids (GCs) are the most effective drugs for the treatment of human asthma. However, a subgroup of asthmatic patients with neutrophilic airway inflammation is insensitive to GCs. Interleukin-17 (IL-17), a cytokine upregulated in the airways of a subset of human asthmatic patients, contributes to the recruitment of neutrophils and induces a glucocorticoid resistance in human airway epithelial cells. We hypothesized that IL-17 similarly activates neutrophils and contributes to their persistence in the asthmatic airways in spite of glucocorticoid therapy. To determine whether IL-17 dire...
Woode GN, Bew ME, Dennis MJ.Inoculation at birth with a live attenuated strain of a bovine rotavirus isolated in the USA (scourvax-reo) induced protection in five gnotobiotic calves seven to 21 days later against a UK isolate of pathogenic bovine rotavirus. However, no protection was induced in three calves challenged three to five days after vaccination. There was a close antigenic relationship demonstrated between the two bovine rotavirus isolates. In contrast only one of three gnotobiotic calves inoculated with foal rotavirus, and one of three with human rotavirus, were protected against bovine rotavirus challenge. Pr...
Carossino M, Dini P, Kalbfleisch TS, Loynachan AT, Canisso IF, Cook RF, Timoney PJ, Balasuriya UBR.Equine arteritis virus (EAV) has the unique ability to establish long-term persistent infection in the reproductive tract of stallions and be sexually transmitted. Previous studies showed that long-term persistent infection is associated with a specific allele of the CXCL16 gene (CXCL16S) and that persistence is maintained despite the presence of local inflammatory and humoral and mucosal antibody responses. Here, we performed transcriptomic analysis of the ampullae, the primary site of EAV persistence in long-term EAV carrier stallions, to understand the molecular signatures of viral persiste...
