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.
Longworth KE.Pulmonary intravascular macrophages are an important part of the mononuclear phagocyte system in some species of mammals, mainly sheep and other ruminants, pigs, and horses. These cells phagocytize foreign particles, cell debris and pathogens that pass through the pulmonary circulation. Species with intravascular macrophages localize intravenously injected tracer particles and bacteria predominantly in the lung rather than the liver, and exhibit pulmonary hypertension when these cells are activated. Both in vivo and in vitro studies show that pulmonary intravascular macrophages have distinct s...
Paweska JT.Clinical, virological and serological responses were investigated in five pregnant donkey mares after experimental exposure to the South African asinine-94 strain of equine arteritis virus (EAV), and the duration of maternal immunity to EAV was studied in their foals. In four intranasally inoculated mares, fever with maximum rectal temperatures of 39.1-40.7 degrees C was recorded 2-11 d after challenge. All the inoculated mares developed mild depression, and a serous ocular and nasal discharge; in three mares mild conjuctivitis was observed. The virus was recovered from the nasopharynx and fro...
Hammond SA, Cook SJ, Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a natural model system by which immunological control of lentivirus infections may be studied. To date, no detailed study addressing in parallel both the humoral and cellular immune responses induced in horses upon infection by EIAV has been conducted. Therefore, we initiated the first comprehensive characterization of the cellular and humoral immune responses during clinical progression from chronic disease to inapparent stages of EIAV infection. Using new analyses of antibody avidity and antibody epitope conformation dependence that had not been...
Moore T, Wilcke J, Chilcoat C, Eyre P, Crisman M.Equine neutrophils (PMN) play a critical role in inflammatory processes in horses. The objective of this study was to characterize equine PMN function ex vivo following stimulation with calcium ionophore A23187 (A23187) and phorbol myristate acetate (PMA). These stimulants trigger different branches of the PMN activation process that occurs in vivo. Equine PMN were isolated from the whole blood of six clinically normal geldings using a one-step discontinuous Percoll gradient technique. Neutrophil aggregation, degranulation, and superoxide anion production were evaluated in assay systems which ...
Hobo S, Oikawa M, Kuwano A, Yoshida K, Yoshihara T.To study the effects of extended transportation on the composition of bronchoalveolar lavage fluid (BALF) obtained from horses. Methods: 30 horses (14 males, 16 females: 25 Thoroughbreds and 5 Thoroughbred-Arabian cross-breds; 27 to 30 months old) without a history or clinical signs of respiratory tract disease. Bronchoalveolar lavage was performed on nontransported control horses (groups 1 and 2) and transported horses (group 3). Methods: 20 horses were used to determine the effect of 41 hours of transportation on the composition of BALF (group 3). Bronchoalveolar lavage fluid was analyzed fo...
Foster AP, McCabe PJ, Sanjar S, Cunningham FM.Eosinophils are believed to play an important part in the pathogenesis of equine diseases such as helminth infestation and the allergic skin disease, sweet itch. It has been shown that adherence of human eosinophils to the connective tissue matrix protein fibronectin enhances cell activation and survival time. If adherence causes similar changes in the properties of equine eosinophils, cell-induced tissue damage at a site of parasitic infestation or allergic response would be exacerbated. However, investigation of this hypothesis requires identification of mediators that cause equine eosinophi...
Kato H, Ohashi T, Matsushiro H, Watari T, Goitsuka R, Tsujimoto H, Hasegawa A.Equine interleukin-1 receptor antagonist (IL-1ra) was molecularly cloned to establish a basis for cytokine therapy of acute and chronic inflammatory diseases in the horse. cDNA clones encoding the whole coding sequence of equine IL-1ra were isolated from equine peripheral blood mononuclear cells (PBMC) that had been stimulated with lipopolysaccharide (LPS). The equine IL-1ra cDNA obtained in this study contained an open reading frame encoding 177 amino acid residues. The predicted amino acid sequence of equine IL-1ra shared 75.7, 75.3 and 76.3% similarity with sequences of human, murine and ra...
Marr KA, Foster AP, Lees P, Cunningham FM, Page CP.The effect of antigen challenge on the state of activation of peripheral blood neutrophils from horses with chronic obstructive pulmonary disease (COPD) has been determined by measuring neutrophil superoxide anion formation. Prior to a seven-hour antigen challenge superoxide anion production by neutrophils from asymptomatic horses with COPD and normal horses in response to platelet activating factor (PAF) (with and without cytochalasin B), serum treated zymosan (STZ) and phorbol myristate acetate (PMA) was similar. Agonist-induced superoxide production by neutrophils from symptomatic COPD and ...
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...
Tschetter JR, Byrne KM, Perryman LE, McGuire TC.Horses infected with equine infectious anemia virus (EIAV) have recurrent episodes of viremia which are eventually controlled, but the immune mechanisms have not been identified. Antibodies were detected to the surface of EIAV-infected cells within 1 month postinfection and remained for at least 3.5 years postinfection. These antibodies recognized cell surface-exposed envelope (Env) glycoproteins, but could not mediate antibody dependent cellular cytotoxicity (ADCC) using EIAV-WSU5-infected equine kidney (EK) cells as targets and peripheral blood mononuclear cells (PBMC) or polymorphonuclear c...
Wood JL, Chanter N, Newton JR, Burrell MH, Dugdale D, Windsor HM, Windsor GD, Rosendal S, Townsend HG.Lower respiratory tract disease developed in a group of racehorses in training between two and six years of age. Disease was observed in 22 of 25 horses for which full records were available. Seroconversion to Mycoplasma felis was demonstrated by indirect haemagglutination assay in 19 of 22 paired sera and high titres (> or = 64) were found in convalescent sera from the three remaining horses. Evidence of respiratory viral infection was confined to seroconversions to equine herpesvirus-4 in two of the horses. Tracheal wash samples, taken from four horses with visibly increased tracheal muco...
Hurwitz A, Finci-Yeheskel Z, Milwidsky A, Yagel S, Adashi EY, Laufer N, Mayer M.To examine the participation of the theca-interstitial (TI) compartment in cytokine modulation of ovarian function, the effects of interleukin-1beta (IL-1) on plasminogen activator (PA) activity and on prostaglandin E (PGE) and nitric oxide (NO) production were examined in cultures of pregnant mare serum gonadotrophin (PMSG)-primed rat TI cells. Exposure to IL-1 (10 ng/ml) resulted in a 25% reduction (P < 0.001) in PA activity, concurrent with a 4.6-fold increase in the ability of the corresponding conditioned media to inhibit exogenous urokinase activity. IL-1 also produced a 4.7-fold incr...
Charan S, Palmer K, Chester P, Mire-Sluis AR, Meager A, Edington N.Up to 21 days after exposure to live or ultraviolet-inactivated equid herpesvirus type-1 (EHV-1) autologous serum from ponies caused an immunosuppressive effect if incorporated into T-cell proliferation assays to EHV-1. The suppressive factor in the sera of ponies also inhibited T-cell response to phytohaemagglutinin. Increased levels of circulating activated transforming growth factor-beta 1 (TGF-beta 1) were detected, and the suppressive activity of the serum could be reversed by antibody to TGF-beta 1. In a challenge experiment the ponies which exhibited circulating TGF-beta 1 activity succ...
Watson JL, Stott JL, Blanchard MT, Lavoie JP, Wilson WD, Gershwin LJ, Wilson DW.The alterations in lymphocyte subsets in chronic obstructive pulmonary disease (COPD) in the horse were investigated by using monoclonal antibodies to identify CD3+, CD4+, CD8+, and surface immunoglobulin positive (sIg+) lymphocytes in peripheral blood, bronchoalveolar lavage fluid (BALF), and pulmonary biopsy frozen tissue sections. COPD-affected horses (n = 5) and normal controls (n = 5) were sampled prestabling and 14 days poststabling, at which time the COPD-affected horses wee exhibiting clinical signs of COPD. The peripheral blood absolute CD4+ lymphocyte count was significantly elevated...
Lány P, Pospísil Z, Zendulková D, Cíhal P, Jahn P.A mild outbreak of acute respiratory infection was reported in racing horses in the fall of 1995. Four studs were investigated for the sources and routes of infection. In five horses from two herds, virus isolates were obtained which, in preliminary typing experiments, were identified as the influenza A/equi 2 virus. The presence of this illness in all the examined herds was confirmed by a rise in specific antibody titres. The affected animals included both older vaccinated horses and young horses not yet vaccinated. Epidemiological studies suggested that the spread of infection occurred in si...
Chesters PM, Steele M, Purewal A, Edington N.A 2.6 kb cDNA species has been isolated from a cDNA library prepared from interferon-alpha stimulated equine peripheral blood leucocytes and the nucleotide sequence determined. The cDNA has a single open reading frame potentially encoding a 660 amino acid polypeptide showing a high degree of homology with known mammalian Mx proteins, including the possession of three consensus GTP-binding motifs. The protein has a calculated pI = 6.1 and in accordance with proposed nomenclature we have designated it equine MxA.
Adeyefa CA, McCauley JW, Tomori O.The complete amino acid sequences of the hemagglutinin (HA) glycoprotein of three equine-2 influenza viruses from tropical Africa are presented in comparison with that of a well characterized European equine-2 virus (Suffolk/89) and a consensus sequence from the database. The sequences of the tropical African viruses were deduced from the complete nucleotide sequences of their HA genes reported earlier. Mutational changes in the nucleotide sequences resulted in amino acid changes in the HA which led to the introduction of a new asparagine-linked (N-linked) glycosylation site in two viruses. Th...
Lakritz J, Wilson WD, Watson JL, Hyde DM, Mihalyi J, Plopper CG.To determine whether oral administration of erythromycin alters the inflammatory response to bronchoalveolar lavage (BAL) in young horses. Methods: 12 healthy, unweaned, mixed-breed foals of either sex, between 2 and 4 months old. Methods: BAL was performed; 250 ml of phosphate-buffered saline solution (300 mOsm, pH 7.4) was administered in 50-ml aliquots. Foals were carefully monitored for 4 days, then erythromycin base (25 mg/kg of body weight, PO, q 12 h) was given to foals of the treated group. After 4 days, foals were reanesthetized, and the same lung was relavaged. Cytologic examination ...
MacDonald MH, Benton HP.To determine the influence of activated equine neutrophils on sulfated glycosaminoglycan metabolism of equine articular cartilage in vitro. Methods: Articular cartilage explants harvested from the metacarpophalangeal joints of 7 horses. Methods: Proteoglycan degradation and synthesis were measured by release of glycosaminoglycan from the explants, and incorporation of [35S]sulfate into newly synthesized glycosaminoglycan. Results: Activated equine neutrophils significantly increased the release of glycosaminoglycan from explant matrix and the magnitude of that response was influenced by durati...
Crawford TB, Wardrop KJ, Tornquist SJ, Reilich E, Meyers KM, McGuire TC.The purpose of this study was to identify the mechanisms responsible for the thrombocytopenia that develops following infection of horses by the lentivirus equine infectious anemia virus (EIAV). Immunocompetent Arabian foals and Arabian foals with severe combined immunodeficiency (SCID), which lack functional B and T lymphocytes, were experimentally infected with EIAV. Levels of viremia and a number of clinical and hematologic parameters were examined prior to and following infection. Thrombocytopenia was not dependent on the immune response: SCID foals were affected as severely as immunocompe...
Sellon DC, Walker KM, Russell KE, Perry ST, Fuller FJ.Equine infectious anemia virus (EIAV) is a lentivirus that replicates predominantly in mature tissue macrophages. Viral expression is strongly influenced by the state of differentiation of the host cell. While blood monocytes can be infected, viral transcription is limited until the cell differentiates into a mature macrophage. Activation of mature macrophages infected with EIAV might also alter viral expression, presumably through binding of cellular transcription factors to viral nucleic acid sequences within the long terminal repeat (LTR). Using DNA amplification techniques, we compared LTR...
Barton MH, Collatos C, Moore JN.Peritoneal fluid was collected aseptically from 30 healthy adult horses and 115 horses with acute gastrointestinal disease and supernatant was separated from cells by centrifugation followed by freezing until assayed for endotoxin and tumour necrosis factor activity. Peritoneal macrophages obtained from healthy horses were incubated in vitro for 3, 6, 12 or 24 h in the absence (media control) or presence of Escherichia coli 055:B5 endotoxin (final concentrations of 1, 10, 100 or 1000 ng/ml). Macrophages obtained from horses with acute gastrointestinal disease were incubated for 12 h in the abs...
Hines MT, Schott HC, Bayly WM, Leroux AJ.Exercise has been recognized as a stress, which can significantly alter the host's immune response and, therefore, its susceptibility to disease. Whereas research in this area has previously focused primarily on human subjects and laboratory animals, it has more recently extended to domestic animals, especially the equine athlete. Despite several studies, defining the relationship among exercise, the immune response, and disease has proven difficult due to a number of factors, including the complexity of the immune system and the variable nature of exercise itself. It now appears that exercise...
Fairbairn SM, Marr KA, Lees P, Cunningham FM, Page CP.Antigen challenge is known to cause the recruitment of neutrophils to the lungs of horses with chronic obstructive pulmonary disease (COPD). To evaluate a possible role of platelet activating factor (PAF) in this process, the effects of PAF on the distribution of radiolabelled neutrophils were compared in normal horses and asymptomatic horses with COPD. Changes in lung function, heart rate and the distribution of platelets and eosinophils were also measured. PAF (5 ng kg-1 intravenously) caused immediate but transient increases in the number of radiolabelled neutrophils in the lungs and a conc...
Dowsett KF, Knott LM, Tshewang U, Jackson AE, Bodero DA, Trigg TE.To investigate the effect of two dose rates (200 and 400 ng) of a gonadotrophin releasing hormone (GnRH) vaccine on testicular function. Methods: A vaccination dose rate experiment. Methods: Two injections were administered 4 weeks apart to six colts in each treatment group. To maintain immunosuppression until the end of the breeding season, a third injection was given if antibody titres fell below 1000. Results: Effective antibody titres were present for 12 to 27 weeks. Testosterone concentrations decreased from 2.22 to 0.31 nmol/L 6 weeks after primary vaccination. Androstenedione concentrat...
Todhunter PG, Kincaid SA, Todhunter RJ, Kammermann JR, Johnstone B, Baird AN, Hanson RR, Wright JM, Lin HC, Purohit RC.To use lipopolysaccharide (LPS) to create synovitis in the midcarpal joint of ponies, and to assess the morphologic, histochemical, and immunohistochemical effects of synovitis on articular cartilage of the third carpal bone. Methods: 2- to 3-year-old ponies, 6 control (group 1) and 6 treated (group 2). Methods: Synovitis was induced in 1 midcarpal joint of group-2 ponies by intra-articular injections of LPS (0.02 micrograms/kg of body weight), morphine (0.1 mg/kg), and saline solution (group 2a) and a morphine and saline solution alone in the contralateral midcarpal joint (group 2b). Articula...
Edens LM, Crisman MV, Toth TE, Ahmed SA, Murray MJ.The objectives of this study were to: (1) develop a technique to analyze the in vitro cytotoxic activity of lymphocytes from adult horses against equine herpesvirus-1 (EHV-1) infected allogenic equine dermal fibroblasts (EDF); (2) evaluate the ability of a 72-h in vitro incubation with interleukin-2 (IL-2) to enhance the lymphocytic cytolytic activity against EHV-1 infected EDF; (3) compare the cytotoxic activity of lymphocytes isolated from pregnant mares and non-pregnant mares against EHV-1 infected EDF; (4) ascertain if any correlations existed between the percent cytotoxicity and percentag...
Allen GK, Campbell-Beggs C, Robinson JA, Johnson PJ, Green EM.Six, clinically healthy horses, of mixed age and sex, were infused via a jugular venous catheter with 100 ml of pyrogenfree sterile saline (PFSS; 0.9% NaCl). Animals were infused with Escherichia coli O55:B5 endotoxin (total dose = 50 ng/kg bwt), 24 (LPS-1) and 48 h (LPS-2) after PFSS infusion. Blood was collected before, and every 15 min after, each infusion for the first 8 h and then every 2 h for the following 14 h. Clinical responses (rectal temperature, heart rate, respiration rate and blood pressure) were determined before and every 4 h after each infusion for 20 h. Geometric mean anti-e...
Harkins JD, Carney JM, Meier M, Leak SC, Tobin T.Lipopolysaccharide (LPS), or endotoxin, is a component of the cell wall of gram-negative bacteria and is toxic to humans and animals. The GI tract of horses contains large numbers of endotoxins which may cause disease if gut wall integrity is compromised. The objective of this study was to develop a unique therapeutic approach to the treatment of endotoxemia with a sulfonyl analog of the alpha-phenyl-N-tert-butyl-nitrone (PBN) spin-trap molecule which may prevent the LPS-induced cytokine cascade. Following challenge with 55 mg/kg LPS, the survivability of ICR Swiss mice was significantly impro...
Paweska JT.Clinical, virological and serological responses were investigated in five pregnant donkey mares after experimental exposure to the South African asinine-94 strain of equine arteritis virus (EAV), and the duration of maternal immunity to EAV was studied in their foals. In four intranasally inoculated mares, fever with maximum rectal temperatures of 39.1-40.7 degrees C was recorded 2-11 d after challenge. All the inoculated mares developed mild depression, and a serous ocular and nasal discharge; in three mares mild conjuctivitis was observed. The virus was recovered from the nasopharynx and fro...
Momoi Y, Kato H, Youn HY, Aida H, Takagi S, Watari T, Goitsuka R, Tsujimoto H, Hasegawa A.Levels of granulocyte-colony stimulating factor (G-CSF) in the blood of horses were measured before and after a long-distance transportation to clarify the pathogenesis of transportation-induced fever. The serum G-CSF level was measured by its ability to stimulate growth in a mouse myeloblastic cell line, NFS-60. Of 26 horses transported for a long distance, 9 had fever more than 39.0 degrees C during or after transportation. After transportation, the serum G-CSF level significantly increased in horses with transportation-induced fever but not in those without fever, and the serum G-CSF level ...
Easton-Jones CA, Estell KE, Magdesian KG.Information concerning clinical presentation, conditions associated with immune-mediated haemolytic anaemia (IMHA) and thrombocytopenia (IMTP) and outcome in equids is lacking. Previous case reports suggest that immune-mediated disease and neoplasia are associated. Objective: Characterise the clinical presentation, clinicopathologic data, underlying conditions, treatment and outcome of IMHA and IMTP cases in equids. We hypothesise that IMHA with concurrent thrombocytopenia occurs more often than IMHA or IMTP alone, and that neoplasia is commonly associated with these immune diseases and cases ...
Hallamaa RE, Batchu KC, Tallberg T.Equine summer eczema, also known as insect bite hypersensitivity, affects horses recurrently during summer months. The treatment of this allergic pruritus is difficult and therefore there is a need for efficacious treatments. Autoserum therapy, based on the use of autogenous serum that is specifically prepared for oral administration and given when the animal shows clinical signs has been introduced recently. Lipids are thought to be responsible for the effect of this therapy. Objective: The main aim of this study was to analyse the phospholipid content of autogenous serum preparations and to ...
Boorman S, Hanson RR, Velloso Alvarez A, Zhong K, Hofmeister E, Boone LH.To determine the effect of concurrent versus delayed treatment with corticosteroid on equine articular tissues also treated with local anesthetic in vitro in the presence of inflammatory mediators. Methods: Controlled laboratory study. Methods: Five geldings, one mare (aged 3-18 years). Methods: From each horse, 24 synovial and 12 osteochondral explants were cultured in a 12-well plate (2 wells/group, 2 synovial and 1 osteochondral explant/well, total 216 explants in the study). Explants were stimulated in culture medium with 10 μg/ml recombinant equine interleukin-1β and 10 μg/ml tumor...
Pawlas-Opiela M, Jawor P, Galli J, Zak-Bochenek A, Gorczykowski M, Galli J, Sołtysiak Z, Stefaniak T.Infection with Gasterophilus intestinalis (botfly) larvae often occurs in horses. The aim of the study was to isolate the larvae of G. intestinalis and evaluate the serum and salivary humoral immune response using self-developed ELISA in G. intestinalis infected horses. Blood serum or saliva samples were taken from 125 infected horses and 54 uninfected slaughtered horses. The antigens from G. intestinalis larvae were used for development of ELISA in order to evaluate the intensity of G. intestinalis IgG, IgM, and IgA antibody reactivity in the serum or saliva of naturally infected horses and h...
Reemers S, van Bommel S, Cao Q, Sutton D, van de Zande S.Equine influenza virus (EIV) is a major cause of respiratory disease in horses. Vaccination is an effective tool for infection control. Although various EIV vaccines are widely available, major outbreaks occurred in Europe in 2018 involving a new EIV H3N8 FC1 strain. In France, it was reported that both unvaccinated and vaccinated horses were affected despite >80% vaccination coverage and most horses being vaccinated with a vaccine expressing FC1 antigen. This study assessed whether vaccine type, next to antigenic difference between vaccine and field strain, plays a role. Horses were vaccin...
El-Hage C, Hartley C, Savage C, Watson J, Gilkerson J, Paillot R.During Australia's first and only outbreak of equine influenza (EI), which was restricted to two northeastern states, horses were strategically vaccinated with a recombinant canarypox-vectored vaccine (rCP-EIV; ProteqFlu™, Merial P/L). The vaccine encoded for haemagglutinin (HA) belonging to two equine influenza viruses (EIVs), including an American and Eurasian lineage subtype that predated the EIV responsible for the outbreak (A/equine/Sydney/07). Racehorses in Victoria (a southern state that remained free of EI) were vaccinated prophylactically. Although the vaccine encoded for (HA) belon...
Otten N, Marti E, Söderström C, Amtmann E, Burger D, Gerber H, Lazary S.A xanthate compound with antiviral and antitumoural activities, tricyclodecan-9-yl-xanthogenate (D609) in combination with the potassium salt of the lauric acid (KC12) and, in a further investigation, the above-mentioned substances together with recombinant human TNF alpha (rh-TNF alpha), were tested on equine sarcoid tumours for therapeutic efficacy. A pilot investigation on 5 healthy horses showed that the compounds were well-tolerated; apart from a local, temporary oedema at the injection site, no other clinical symptoms were observed after subcutaneous administration of volumes from 0.1 to...
Kahn SK, Cywes-Bentley C, Blodgett GP, Canaday NM, Turner-Garcia CE, Vinacur M, Cortez-Ramirez SC, Sutter PJ, Meyer SC, Bordin AI, Vlock DR, Pier GB....The efficacy of transfusion with hyperimmune plasma (HIP) for preventing pneumonia caused by Rhodococcus equi remains ill-defined. Quarter Horse foals at 2 large breeding farms were randomly assigned to be transfused with 2 L of HIP from adult donors hyperimmunized either with R. equi (RE HIP) or a conjugate vaccine eliciting antibody to the surface polysaccharide β-1→6-poly-N-acetyl glucosamine (PNAG HIP) within 24 hours of birth. Antibody activities against PNAG and the rhodococcal virulence-associated protein A (VapA), and to deposition of complement component 1q (C՛1q) onto PNAG were d...
Murakami K, Sentsui H, Shibahara T, Yokoyama T.Three horses were experimentally infected with equine infectious anemia virus (EIAV). All horses were febrile after inoculation with EIAV and then developed chronic symptoms with intermittent fever. The febrile period was characterized by a rise in body temperature with reduced PBL and erythrocyte counts. Flow cytometric analysis showed that the reduced number of lymphocytes was due to significant decreases in CD4+ and CD8+ T cells in the absence of any change in B cell number. At the end of the febrile period the body temperature began to recover and numbers of CD4+ and CD8+ T cells showed a ...
McLean R, Rash NL, Robinson C, Waller AS, Paillot R.Streptococcus equi subspecies equi (S. equi) is the causative agent of strangles, a highly contagious upper respiratory disease of equids. Streptococcus equi produces superantigens (sAgs), which are thought to contribute to strangles pathogenicity through non-specific T-cell activation and pro-inflammatory response. Streptococcus equi infection induces abscesses in the lymph nodes of the head and neck. In some individuals, some abscess material remains into the guttural pouch and inspissates over time to form chondroids which can harbour live S. equi. The aim of this study was to determine...
Liu C, Cook SJ, Craigo JK, Cook FR, Issel CJ, Montelaro RC, Horohov DW.Unlike other lentiviruses, EIAV replication can be controlled in most infected horses leading to an inapparent carrier state free of overt clinical signs which lasts for many years. While the resolution of the initial infection is correlated with the appearance of virus specific cellular immune responses, the precise immune mechanisms responsible for control of the infection are not yet identified. Since the virus undergoes rapid mutation following infection, the immune response must also adapt to meet this challenge. We hypothesize that this adaptation involves peptide-specific recognition sh...
Yilma T, Perryman LE, McGuire TC.The results of a study on the induction of IFN-alpha, IFN-beta, and IFN-gamma in normal and SCID foals showed a deficiency of IFN-gamma but not IFN-beta in SCID foals. The ability of SCID mononuclear cells to produce IFN-alpha in response to poly I:C but not to NDV may indicate a partial deficiency of IFN-alpha in SCID foals. The deficiency of IFN-gamma and presence of IFN-beta in SCID foals supports the classification of IFN-gamma and IFN-beta as immune and nonimmune interferons, respectively. Furthermore, the deficiency of IFN-gamma in SCID foals may in part explain the high susceptibility t...
Plowright W.An account is presented of the development and use of herpesvirus vaccines in domestic animals, with particular reference to those viruses causing cytolytic rather than oncogenic infections. The chief infections covered are Aujeszky's disease (AD or pseudorabies), infectious bovine rhinotracheitis (IBR) and equine rhinopneumonitis (equine abortion; EHV-1). Others mentioned are feline viral rhinotracheitis and malignant catarrhal fever of cattle. Both live-modified and inactivated vaccines are widely used or under development for ADV, IBR and EHV-1. Live vaccines are generally regarded as succe...
AbdelKhalek A, Ostafe R, Olave C, HogenEsch H, Turner JW.Immunization with porcine zona pellucida (PZP) proteins is being used successfully to induce infertility in wildlife including horses. However, widespread adoption of this method to control the growth of horse populations requires further refinement in order to induce long-term infertility, reduce the frequency and severity of injection site reactions, and make the vaccines easier to administer. The next generation of PZP-based vaccines will likely be a controlled-release formulation with different adjuvants from the Freund's adjuvants used in existing vaccines. We evaluated the response of eq...
Semrad SD, Moore JN.Thromboxane A2 may play a major role in circulatory shock. In some species, thromboxane synthetase inhibitors have a beneficial effect on shock induced by endotoxin, trauma, sepsis and administration of arachidonate. In some shock models, however, results with thromboxane synthetase inhibitors have been conflicting. The effect of UK-38,485, a selective thromboxane inhibitor, was evaluated in ponies injected with endotoxin intraperitoneally. Four groups of ponies were used to compare the effects of endotoxin alone, UK-38,485 alone, treatment with UK-38,485 before endotoxin challenge and treatme...
Uhl EW, Giguère S, Jack TJ, Hodge T.Previous studies revealed that foals inoculated with virulent Rhodococcus equi had significantly higher pulmonary levels of interleukin-1beta, interleukin-12 p40, interferon-gamma, and tumor necrosis factor-alpha mRNA compared to foals inoculated with an avirulent plasmid-cured derivative. The purpose of this study was to determine if the increases in cytokine expression were associated with increased pulmonary activation of nuclear factor-kappaB (NF-kappaB). Electrophoretic mobility shift assays were performed on pulmonary nuclear protein extracted from foals treated with phosphate-buffered s...
Istanbullugil FR, Risvanli A, Salikov R, Bayraktar M, Kadiraliyeva N, Zhunushova A, Yilmaz O, Yuksel BF, Turanli M, Uz M, Asinbekovic MI.Immune compatibility between mare and foal is one of the important topics of reproductive immunology. At this point, although there are many studies on antibodies, there are not many publications on the relationship between the cytokine levels of mare, foal and milk and the effects of milk composition on this relationship. Here we investigate the relationship between Th1/Th2 cytokine balance and milk composition in Kyrgyz mares and foals. Samples were taken soon after the foal was born and on days 5, 10 and 20 after birth. Th1 (IFN-γ, IL-2, TNF-α) and Th2 (IL-4, IL-5, IL-10) cytokine levels ...
Vanderwagen LC, Pearson JL, Franti CE, Tamm EL, Riemann HP, Behymer DE.As a result of the continuing threat of Venezuelan equine encephalomyelitis (VEE), a study was made to determine if revaccination against VEE (TC-83 vaccine) was feasible and if revaccination could be incorporated into other routine vaccination practices. Of the horses given annual vaccination with bivalent western equine encephalomyelitis (WEE) and eastern equine encephalomyelitis (EEE) vaccine, 57% retained detectable serum-neutralizing (SN) antiboyd titers for VEE 18 months after the initial VEE vaccination was given. Of horses with no record of WEE-EEE vacinnation, 100% retained detectable...
Hall JA, Hoyt D, Zuver C, Skinner MM, Schlipf JW.The criteria used to diagnose recurrent airway obstruction (RAO) in affected horses include demonstration of reversible lower airway obstruction and greater than 25% neutrophils in bronchoalveolar lavage fluid (BALF). Additional objective laboratory tests are needed to improve diagnostic accuracy and to monitor response to treatment. The goal of this study was to determine if neutrophil chemoattractant activity of BALF could be measured by using a previously described, rapid, multiwell colorimetric assay for chemotaxis. In this assay, neutrophils that have migrated through a membrane filter ar...
Salinas C, Espinosa G, Morales N, Henríquez C, Morán G, Gajardo G, Burgos RA, Uberti B.Obesity and insulin dysregulation (ID) are increasingly prevalent conditions in equid populations worldwide. Immune impairment is well described in humans with metabolic dysfunction and is reported but still incompletely understood in horses. This study evaluated the effect of acute induced transient hyperglycemia on apoptosis, phagocytosis and oxidative burst activity of peripheral blood polymorphonuclear cells (PMN) of lean and obese adult horses with or without insulin dysregulation. Seventeen adult horses were allocated into three groups based on their body condition score (BCS) and metabo...
van Dorland HA, Zanoni R, Gerber V, Jeannerat E, Wiederkehr D, Burger D.Bio-Strath is a plasmolyzed yeast product enriched with herbs, malt, honey and orange juice. In this study, the effect of Equi-Strath , the adapted product for horses, on the equine immune system was evaluated. A routine influenza booster vaccination was used as a model to study the effects of Equi-Strath supplementation on the immune response. Twenty healthy Franches-Montagnes stallions with pre-existing antibody levels were randomly divided into a study group (SG, n = 10) receiving 0.06 mL/kg bodyweight of Equi-Strath , and a control group (CG, n = 10), receiving the same amount of plac...
Tukia E, Wagner B, Vainio K, Mönki J, Kareskoski M.Postpartum metritis in mares is a life-threatening condition associated with severe clinical signs due to endotoxemia, and it is often followed by complications such as laminitis. Repeated large-volume uterine lavages are commonly recommended as a part of the treatment protocol to remove endotoxin-laden contents from the uterus. It has, however, also been suggested that lavages may increase the uptake of endotoxin into the circulation, leading to a deterioration of clinical signs. Endotoxemia is associated with the release of a multitude of inflammatory mediators regulating the immune response...
Kim EJ, Kim BH, Yang S, Choi EJ, Shin YJ, Song JY, Shin YK.In this study, antibody responses after equine influenza vaccination were investigated among 1,098 horses in Korea using the hemagglutination inhibition (HI) assay. The equine influenza viruses, A/equine/South Africa/4/03 (H3N8) and A/equine/Wildeshausen/1/08 (H3N8), were used as antigens in the HI assay. The mean seropositive rates were 91.7% (geometric mean antibody levels (GMT), 56.8) and 93.6% (GMT, 105.2) for A/equine/South Africa/4/03 and A/equine/Wildeshausen/1/08, respectively. Yearlings and two-year-olds in training exhibited lower positive rates (68.1% (GMT, 14) and 61.7% (GMT, 11.9)...
Grünig G, Witschi U, Winder C, Hermann M, von Fellenberg R.Supernatants of equine respiratory secretions enhanced the migration of equine neutrophils into the lower compartments of Boyden chambers. Checkerboard analysis revealed that the neutrophil migration promoting activity (NMPA) of secretion specimens was in great part caused by chemokinesis, irrespective of the neutrophil score of the specimen. The NMPA of respiratory secretions was correlated neither with the neutrophil score of the secretion specimen nor with the severity of the chronic pulmonary disease. Respiratory secretions collected while horses were kept under low dust or under dusty hou...
Benbarek H, Deby-Dupont G, Deby C, Serteyn D.The capacity of the two cytokines TNF-alpha and IL-1beta to directly stimulate the oxidative activity of polymorphonuclear neutrophils remains debated. The purpose of this study was to verify if a direct stimulation of equine neutrophils by TNF-alpha and IL-1beta was possible. Equine neutrophils were isolated from blood by discontinuous density gradient centrifugation. The cell viability after isolation was >98%. The neutrophils were used at 1.25 x 10(6) cells by assay, immediately after isolation. The oxidative activity of neutrophils was measured by luminol- or lucigenin-enhanced chemilumine...
Hubert JD, Seahorn TL, Klei TR, Hosgood G, Horohov DW, Moore RM.The objective of this study was to determine the effect of infection with Strongylus vulgaris on serum cytokines and plasma nitric oxide (NO) concentrations in helminth-naive ponies. Group 1 (n = 21) was given 500 S. vulgaris L3 larvae and group 2 (n = 7) received a saline control. Ponies were monitored daily for clinical signs, and blood was collected for complete blood cell counts and serum cytokines (TNF, IL-1, IL-6) quantification. Group 1 ponies were depressed, anorexic, and febrile for variable periods of time. Plasma NO was increased on day 21 in group 1 and on days 9 and 21 in group 2....
Mantovani A, Caporale V, Ciuchini F, Di Trani L, Irsara A, Prosperi S.The results of antibody titrations in different animal species vaccinated against rabies are reported. The following points are considered: (1) antibody titration may be used to detect an immunity status in dogs, (2) equines should be vaccinated in infected areas, (3) experiments in progress are comparing ERA vaccine and an inactivated vaccine in bovines, and (4) the vaccination of fallow deer (Dama dama) and moufflons (Ovis ammon musimon) produced results suggesting an extension of the experiment with the purpose of vaccinating wild ruminants whenever possible.
