The equine immune system is a complex network of cells, tissues, and organs that work collaboratively to defend against pathogens and maintain homeostasis. It consists of innate and adaptive components, each with distinct functions and mechanisms. The innate immune system provides the first line of defense through physical barriers, phagocytic cells, and the complement system. The adaptive immune system involves lymphocytes, such as B cells and T cells, which generate specific responses to antigens and provide immunological memory. Research in equine immunology explores the interactions between these components, the impact of genetic and environmental factors on immune function, and the development of vaccines and therapeutics. This page gathers peer-reviewed studies and scholarly articles focusing on the mechanisms, regulation, and clinical applications of the equine immune system in health and disease.
Hedges JF, Balasuriya UB, Timoney PJ, McCollum WH, MacLachlan NJ.The persistently infected carrier stallion is the critical natural reservoir of equine arteritis virus (EAV), as venereal infection of mares frequently occurs after breeding to such stallions. Two Thoroughbred stallions that were infected during the 1984 outbreak of equine viral arteritis in central Kentucky subsequently became long-term EAV carriers. EAV genomes amplified from the semen of these two stallions were compared by sequence analysis of the six 3' open reading frames (ORFs 2 through 7), which encode the four known structural proteins and two uncharacterized glycoproteins. The major ...
Kim SK, Bowles DE, O'callaghan DJ.The equine herpesvirus 1 immediate-early (IE) phosphoprotein is essential for the activation of transcription from viral early and late promoters and trans-represses its own promoter. Transient-transfection assays showed that the IE protein trans-represses the gamma2 late gK promoter. Gel shift and DNase I footprinting assays demonstrated that the IE protein binds to the gK promoter sequences from -42 to -26 and from -13 to +12 that overlap the transcription initiation site (+1). These results indicated that the IE protein binds to the transcription initiation site of the gK promoter sequences...
Gröndahl G, Johannisson A, Demmers S, Jensen Waern M.The aim of this study was to evaluate the influence of age and plasma treatment on neutrophil phagocytosis, CD18 expression and serum opsonic capacity in foals in field settings. Microbial infections constitute a large threat in young foals and neutrophil functions are crucial for the defense. Blood samples were obtained from 13 foals at seven time points between the ages of 2 and 56 days and once from 16 adult horses. Six of the foals were treated with adult plasma at the age of 1 week. Neutrophil phagocytosis of yeast after various opsonizations and the expression of complement adhesion rece...
Hobo S, Ogasawara Y, Kuroki Y, Akino T, Yoshihara T.To characterize surfactant protein D (SP-D) isolated from bronchoalveolar lavage fluid (BALF) of healthy horses. Methods: BALF from 10 Thoroughbreds (5 males, 5 females; 26 to 40 months old) without history or clinical signs of respiratory tract disease. Methods: BALF was obtained and centrifuged at 33,000 X g. The supernatant was applied to a mannose-Sepharose 6B affinity column in the presence of calcium, and the bound protein fraction was analyzed by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblot analysis; amino acid composition was determined and partial seque...
Banks EM, Kyriakidou M, Little S, Hamblin AS.Leucocytes in the lung epithelium play an important role in the ability of an animal to respond appropriately to inhaled pathogens. The distribution of lymphoid and myeloid cells associated with the lung epithelium was examined immunohistochemically throughout the respiratory tract of four horses, comprising two adults from an abattoir, one pregnant mare, and her fetus (in the final stage of gestation). Cross and tangential cryosections were labelled with monoclonal antibodies against T-cell, B-cell, macrophage/dendritic myeloid cell, and major histocompatibility Class (MHC) II surface antigen...
The Journal of infectionMarch 25, 1999
Volume 38, Issue 1 22-23 doi: 10.1016/s0163-4453(99)90023-3
McCormack JG, Allworth AM, Selvey LA, Selleck PW.Determination of potential infectivity of a new paramyxovirus equine morbillivirus (EMV) from horses to humans and humans to humans as a result of two outbreaks in Queensland which involved 23 horses and three humans. Methods: Seroepidemiological testing using neutralizing and immunofluorescing antibodies on people with variable levels of exposure to infected horses and humans. Results: All serological testing on a total of 298 individual contacts was negative. Conclusions: While the three human cases of EMV were probably infected as a result of very close contact with horses, these data sugge...
Sellon DC, Russell KE, Monroe VL, Walker KM.Seven ponies were infected with the virulent wild-type Wyoming strain of equine infectious anaemia virus (EIAV). Infection status was monitored by serum reverse transcriptase activity, rectal temperature, and complete blood count. Preinfection serum and serum obtained during the initial febrile episode following infection were assayed for interleukin 6 (IL-6) activity. Postinfection IL-6 activity was significantly increased as compared to preinfection values. The magnitude of increase in IL-6 was positively correlated with reverse transcriptase activity (an indirect measure of viraemia) but wa...
Gatti JL, Druart X, Guérin Y, Dacheux F, Dacheux JL.SDS-PAGE analysis of luminal fluid from the ram testis and epididymis revealed a protein of about 105 kDa in the fluid in the caput epididymal region. The molecular mass of this fluid protein shifted from 105 kDa to 94 kDa in the distal caput epididymidis and remained at 94 kDa in the lower regions of the epididymis. The possible sperm origin of this protein was suggested by the decrease in intensity of a 105-kDa compound on the sperm plasma membrane extract and by its total disappearance from the fluid of animals with impaired sperm production caused by scrotal heating. The 94-kDa protein was...
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 ...
Lonning SM, Zhang W, Leib SR, McGuire TC.Cytotoxic T lymphocytes (CTL) appear to be critical in resolving or reducing the severity of lentivirus infections. Retroviral vectors expressing the Gag/Pr or SU protein of the lentivirus equine infectious anemia virus (EIAV) were constructed and used to evaluate EIAV-specific CTL responses in horses. Three promoters, cytomegalovirus, simian virus SV40, and Moloney murine sarcoma virus (MoMSV) long terminal repeat (LTR), were used, and there was considerable variation in their ability to direct expression of Gag/Pr and SU. Vectors expressing EIAV proteins under the direction of MoMSV LTR and ...
Hobo S, Ogasawara Y, Kuroki Y, Akino T, Yoshihara T.To characterize surfactant protein isolated from bronchoalveolar lavage fluids of healthy horses. Methods: 10 Thoroughbreds (5 males, 5 females; 26 to 40 months old) that did not have a history or clinical signs of respiratory tract disease. Methods: Bronchoalveolar lavage fluid (BALF) was obtained and centrifuged at 33,000 X g. Lipid was removed from precipitated fractions by means of extraction with 1-butanol, and organic solvent-insoluble protein precipitates were dialyzed against Tris buffer. The suspension was centrifuged, and supernatant was placed in a mannose-Sepharose affinity column,...
Kitamura HP, Yanase H, Kitamura H, Iwanaga T.Fibroblast-like (Type B) synoviocytes are cells in the synovial membrane that are responsible for production of both synovial fluid and the extracellular matrix in the synovial intima. Immunostaining of the horse synovial membrane for protein gene product (PGP) 9.5, which is a neuron-specific ubiquitin C-terminal hydrolase, demonstrated selective localization of the immunoreactivity in a synoviocyte population different from acid phosphatase-positive Type A synoviocytes. The immunoreactive cells were lined up in the synovial intima and extended dendritic processes towards the joint cavity to f...
Swiderski CE, Klei TR, Horohov DW.Quantification of cytokine mRNA using reverse transcription coupled with the polymerase chain reaction (RT-PCR) has become a corner stone of the study of cytokine regulation. Quantitative competitive RT-PCR (QCRT-PCR) is commonly accepted as a reliable method for quantifying differences in mRNA levels but is both labor- and reagent-intensive. A noncompetitive polymerase chain reaction method that utilizes cytokine-specific, plasmid-derived, standard curves was developed for the quantification of equine cytokine mRNA. The assay can be performed on minute samples of cellular material, utilizes s...
Jahrling PB, Geisbert TW, Geisbert JB, Swearengen JR, Bray M, Jaax NK, Huggins JW, LeDuc JW, Peters CJ.A passive immunization strategy for treating Ebola virus infections was evaluated using BALB/ c mice, strain 13 guinea pigs, and cynomolgus monkeys. Guinea pigs were completely protected by injection of hyperimmune equine IgG when treatment was initiated early but not after viremia had developed. In contrast, mice were incompletely protected even when treatment was initiated on day 0, the day of virus inoculation. In monkeys treated with one dose of IgG on day 0, onset of illness and viremia was delayed, but all treated animals died. A second dose of IgG on day 5 had no additional beneficial e...
Yepez-Mulia L, Arriaga C, Viveros N, Adame A, Benitez E, Ortega-Pierres MG.In order to determine the presence of Trichinella infections in horses slaughtered at an abattoir in Mexico, 147 serum samples were examined by two immunoenzymatic methods. Specific antibodies were detected by ELISA in 7% of the serum samples at a dilution 1:400 and in 10% at lower dilutions (1:20, 1:40) using Trichinella spiralis muscle larvae (ML) excretory/secretory (E/S) products. Serum samples from four naturally infected horses (confirmed by direct methods) gave negative O.D. values in an ELISA at a 1:400 dilution and only two of them were positive at a 1:20 and 1:40 dilutions. Serum sam...
Siedek EM, Whelan M, Edington N, Hamblin A.Equine herpesvirus type 1 (EHV-1) causes respiratory disease, abortion and myeloencephalopathy in horses. As with other herpesviruses, cell-mediated immunity is considered important for both recovery and protection. Although virus-specific T-cell proliferation and cytotoxicity can be detected following in vivo infection, little is known about the role of antigen presenting cells such as dendritic cells (DCs) in these processes. Peripheral blood DCs were shown to express the viral glycoprotein gB perinuclearly following exposure to EHV-1 in vitro, demonstrating EHV-1 replication within them. Co...
Giguère S, Prescott JF.A reverse transcription-competitive polymerase chain reaction (RT-cPCR) method was developed to quantitate equine interleukin (IL)-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12 p35, IL-12 p40, interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), and beta-actin mRNA expression. Using primers based on equine-specific sequences, these cytokines could be detected in concanavalin A-stimulated peripheral blood mononuclear cells. The specificity of the amplified product was confirmed by sequencing. For each cytokine, the assay was made quantitative by generating competitor ...
Pollitt CC, Daradka M.Disintegration of the basement membrane (BM) of the equine hoof lamellae and failure of the BM to remain attached to the basal cells of the secondary epidermal lamellae (SEL) is one of the earliest pathological events to occur in acute laminitis. Changes in the lamellar basement membrane were investigated by immunolabelling the key structural components of the BM, type IV collagen, type VII collagen and laminin in the lamellar BM of horses 48 h after the induction of laminitis. Lamellar tissues were harvested from 2 normal horses and 2 horses with acute laminitis. Immunostaining with antibody ...
Wattle O.The equine skin and its appendages (chestnut, hoof capsule, ergot, sebaceous glands, sweat glands and hair) consist mainly of keratinocytes. The intermediate filament cytoskeleton of these cells in involved in specialised functions, such as mechanical co-ordination of the cytoskeleton of the cell or tissue. In this study, 7 monoclonal antibodies, one polyclonal antibody and immunoblot analysis were used to characterise cytokeratins (separated by 1- and 2-dimensional gel electrophoresis) from the hoof wall and chestnut. The tissue distribution of these cytokeratins was studied by immunohistoche...
Hedges JF, Balasuriya UB, Ahmad S, Timoney PJ, McCollum WH, Yilma T, MacLachlan NJ.Indirect enzyme linked immunosorbant assays (ELISAs) utilizing the three major structural proteins (M, N, and G(L)) of equine arteritis virus (EAV) expressed from recombinant baculoviruses were developed. A large panel of sera collected from uninfected horses, and from animals experimentally and naturally infected with EAV or vaccinated with the modified live virus vaccine against equine viral arteritis, were used to characterize the humoral immune response of horses to the three major EAV structural proteins. The data suggest that the M protein was the major target of the equine antibody resp...
Dagleish MP, Pemberton AD, McAleese SM, Thornton EM, Miller HR, Scudamore CL.Equine alpha-1-proteinase inhibitor (API) consists of three, occasionally four, serum glycoproteins. This study investigated the immunohistochemical localisation of equine API in paraformaldehyde fixed, paraffin embedded equine tissue samples of liver, lung, stomach, pancreas, jejunum and colon in five horses using affinity purified sheep polyclonal and protein A purified mouse monoclonal antibodies, whose specificities were verified by Western blotting. Exposing tissue sections to boiling citrate buffer greatly enhanced antigen recovery and improved immunostaining with both antibodies, result...
Théon AP.Surgery is the mainstay of treatment for equine tumors. Conservative treatment approaches which preserve function and appearance are increasingly used in clinical practice. This article covers the principles and applications of two conservative treatment modalities including local chemotherapy and immunotherapy. The therapeutic benefit of local chemotherapy is based on the direct drug delivery to tumor tissue, i.e., topical and intratumoral administration of cytotoxic agents in slow release formulation. This treatment modality is very effective for cutaneous tumors and does not result in any p...
Cole DJ, Snowden K, Cohen ND, Smith R.Feces collected from three asymptomatic horses and seeded with Cryptosporidium parvum oocysts (10(1) to 10(6)/g of feces) were evaluated by acid-fast staining (AF), an immunofluorescent antibody (IFA) technique, and flow cytometry. The thresholds of detection were 5 x 10(5) oocysts/g of feces for the IFA and AF techniques and 5 x 10(4) oocysts/g for flow cytometry.
Desmettre P.The frequent transfers of horses, whether on a permanent or temporary basis, make strict control of infectious diseases essential. Such control needs a reliable and rapid means to accurately diagnose the relevant diseases. Indirect diagnosis based on antibody detection remains certainly the best method to secure the epidemiologic surveillance of the diseases at regional, national, or even world level, while direct diagnosis is the only way to diagnose a new outbreak. New diagnostic methods resulting from advances in biochemistry, molecular biology, and immunology are now available. As far as a...
Hernández-Vidal G, Jeffcott LB, Davies ME.A polyclonal antiserum raised in sheep against human cathepsin B was tested for specificity and cross-reactivity with the horse homologue by SDS-PAGE and Western blotting, prior to being used for immunolocalization of the enzyme in equine articular cartilage. In Western blots, the antiserum recognized the 30 kDa single chain and 25 kDa heavy chain of the mature enzyme in purified bovine cathepsin B, and corresponding bands at 32 and 27 kDa in equine chondrocyte and fibroblast lysates. This antiserum was then used to compare the expression and distribution of cathepsin B in normal and dyschondr...
Overesch G, Wagner B, Radbruch A, Leibold W.The number of immunoglobulin G constant heavy chain genes (cgamma genes) varies broadly among mammalian species, reflecting structural and functional differences between expressed immunoglobulin G (IgG) isotypes and allotypes. Up to now equine IgG isotypes have been defined only at the biochemical and serological level. It is still not clear how many IgG isotypes exist in horses and whether there are any allotypes. Here, we describe the isolation and characterisation of equine cgamma genes. An equine genomic lambda phage library was screened with a human cgamma4 probe. Cross-hybridising equine...
Kong XG, Pang H, Sugiura T, Matsumoto Y, Onodera T, Akashi H.Equine infectious anemia virus (EIAV) core proteins (Gag and p26) obtained from a baculovirus expression system were used in agar gel immunodiffusion (AGID) and enzyme-linked immunosorbent assay (ELISA) antigens to test seventy-six horse sera. Those sera showed false-positive reaction in AGID test using Nisseiken antigen. However, none of them showed false-positive reaction with both of the expressed antigens. The 76 horse sera were also tested by ELISA. The sera gave a high background in ELISA using Nisseiken antigen. Gag and p26 reacted strongly against positive sera from horses immunized wi...
Menzies-Gow NJ, Bailey SR, Berhane Y, Brooks AC, Elliott J.To determine the effect of endotoxin (lipopolysaccharide [LPS]) on vasoactive mediator production by cultured equine digital vein endothelial cells (EDVECs). Methods: EDVECs obtained from forelimb digital veins of 7 healthy adult horses. Methods: EDVECs were incubated with or without LPS (1 microg/mL) for 0, 2, 4, 6, 22, and 24 hours. The EDVECs were incubated for 18 hours with LPS (10 pg/mL to 1 microg/mL) with or without ibuprofen, cycloheximide, or L-nitroarginine methyl ester. Medium concentrations of prostacyclin, cyclic guanosine monophosphate, endothelin-1, and thromboxane A(2) were det...
Purdy CW, Porter RC, Ford SJ.Immunogenicity and safety of an equine herpesvirus 1 (ehv-1) vaccine were studied in 111 foals varying in age from 1 to 122 days. Each of 88 principals was given 1 im injection of vaccine. Five of the 88 foals were revaccinated; 69 of the vaccinated principals and 23 nonvaccinated foals (serving as controls) were challenge exposed intranasally with virulent ehv-1.
The vaccine failed to cause adverse local or systemic reaction in 88 principals with serunirneutralization (sn) titers against ehv-1 varying between 0 to 1:256 at time of vaccination. After vaccination, the foals' body temperature...
Alwan WH, Carter SD, Dixon JB, Bennett D, May SA, Edwards GB.Synovial fluid samples of horses with osteoarthritis were investigated to detect interleukin-1 (IL-1) activity which could contribute to the disease pathogenesis. Of the 32 samples tested, 12 (37.5 per cent) showed an augmented phytohaemagglutinin induced proliferation of C3H/HeJ mouse thymocytes. Positive results were also seen in horses with infected arthritis, osteochondritis, traumatic arthritis and undefined synovial effusions. Normal synovial fluid and sera from all groups failed to show any detectable IL-1 activity. Fractionation of synovial fluid showed that the IL-1 activity was in th...
Ueda Y, Sanai Y, Homma JY.Enzyme-linked immunosorbent assay (ELISA) was used for detection of immunoglobulin (Ig) M and IgG antibodies against a serologically common antigen (original endotoxin protein), protease, and elastase of Pseudomonas aeruginosa. The P aeruginosa antibody in horse sera was measured, using ELISA. Horseradish peroxidase-labeled rabbit anti-horse IgM and IgG antibodies were used for enzyme-labeled antibody conjugate. 5-Aminosalicylic acid and H2O2 were used for substrate. Sera collected from a vaccinated horse, a newborn foal, and 72 healthy racehorses were investigated for antibodies against P aer...
Herrera MF, Otermin M, Herrera JM, Simoy MV, Bianchi CP, Aguilar JJ, Fumuso EA.Mycobacterium cell wall fraction (MCWF) is a biological component made up of molecules with immunostimulant properties, which is therapeutically used to modulate persistent breeding-induced endometritis (PBIE). The aim of this study was to analyze the effect of this immunomodulator on the endometrial histological structure during the diestrus of PBIE-resistant and -susceptible mares that either received treatment with MCWF or not. The experiment was conducted with 10 resistant mares (RM) and 9 susceptible mares (SM). In the first estrous cycle of the trial, all mares were inseminated with dead...
Stockert JC, Trigoso CI, Tato A, Ferrer JM.The structure of specific granules from horse eosinophil leukocytes is still largely unknown. In this work, electron microscopical studies of horse eosinophils reveal that the large cytoplasmic granules contain an external membrane, a matrix of less density, and a dense (non crystalline) core. Round vacuolar inclusions of matrix materials were often observed within the cores. Horse eosinophil granules showed a considerable heterogeneity, and three morphological types could be identified according to structural features of the core and matrix.
Leid RW, Coley SC, Blanchard DP, Perryman LE.The equine alternative complement pathway has been partially characterized and compared to the equine classical activation pathway. A dose-dependent lysis of RbRBC was observed with peak lytic values noted within 10 minutes at 37 degrees C when rabbit red blood cells (RbRBC) were used as an alternative pathway activator. Sheep red blood cells (SRBC) sensitized with rabbit hemolysin or partially purified equine IgM antibodies were equally sensitive to lysis. Dilution of the commercial hemolysin by 1/5 reduced lysis from 90% to 38% in the presence of constant cell numbers. Hemolysis of SRBC peak...
Leduc L, Leclère M, Lavoie JP.Although horses with asthma share similar clinical signs, the heterogeneity of the disease in terms of severity, triggering factors, inflammatory profile, and pathological features has hindered our ability to define biologically distinct subgroups. The recognition of phenotypes and endotypes could enable the development of precision medicine, including personalized, targeted therapy, to benefit affected horses. While in its infancy in horses, this review outlines the phenotypes of equine asthma and discusses how knowledge gained from targeted therapy in human medicine can be applied to evaluat...
Aleman M.Inflammatory myopathies or myositis encompass diseases characterized by the presence of inflammatory cellular infiltrates, mainly polymorphonuclear cells and/or lymphocytes, in muscle. This is in contrast to most forms of muscle disease characterized by myodegeneration that results in macrophage infiltration. Inflammatory myopathies could have infectious or noninfectious causes. Noninfectious causes consist of primary (genetic, autoimmune) or acquired immune-mediated disease. Focal, multifocal or diffuse, acute or recurrent forms of disease can occur. This article will mainly review immune-med...
Baintner K, Csapó J.Mare's colostrum was collected and examined for the presence of trypsin inhibitors. It was found to contain a low level of trypsin inhibitor which could be denatured by 2.5% trichloroacetic acid and, therefore, it clearly differs from the acid-resistant colostral inhibitor of Artiodactyla and Carnivora. This finding is exceptional for a species that concentrates IgG in the colostrum and whose newborn absorbs colostral proteins non-selectively by the gut. It appears that the presence of colostral trypsin inhibitor is not essential for the transmission of maternal immunity via the colostrum and ...
Safir JM, Loy RG, Fitzgerald BP.To investigate the hypothesis that the onset of the breeding season in the mare may be due to a daylength-induced seasonal increase in LHRH pulse frequency, 5 mares were immunized against LHRH. Beginning 1 December, 5 immunized and 5 untreated control mares were exposed to an abrupt, artificial increase in daylength (16L:8D) to advance the onset of the breeding season. In control mares ovulation occurred 49.6 +/- 3.5 (s.e.m.) days later (18 January), whereas in 3/5 immunized mares ovulation had not occurred by 1 April. In the remaining 2 mares, although ovulation occurred once (Mare 79) or twi...
Ziegler A, Olzhausen J, Hamza E, Stojiljkovic A, Stoffel MH, Garbani M, Rhyner C, Marti E.Allergen-specific immunotherapy (AIT) constitutes the only curative approach for allergy treatment. There is need for improvement of AIT in veterinary medicine, such as in horses suffering from insect bite hypersensitivity, an IgE-mediated dermatitis to Culicoides. Dendritic cell (DC)-targeting represents an efficient method to increase antigen immunogenicity. It is studied primarily for its use in improvement of cancer therapy and vaccines, but may also be useful for improving AIT efficacy. Immunomodulators, like the Toll-like receptor 4 (TLR-4) agonist monophosphoryl lipid-A (MPLA) has been ...
Ostevik L, de Souza GA, Wien TN, Gunnes G, Sørby R.Two horses with chronic uveitis and histological lesions consistent with equine recurrent uveitis (ERU) were examined. Microscopical findings in the ciliary body included deposits of amyloid lining the non-pigmented epithelium, intracytoplasmic, rod-shaped, eosinophilic inclusions and intraepithelial infiltration of T lymphocytes. Ultrastructural examination of the ciliary body of one horse confirmed the presence of abundant extracellular deposits of non-branching fibrils (9-11 nm in diameter) consistent with amyloid. Immunohistochemistry revealed strong positive labelling for AA amyloid and m...
Gregg AJ, Schenkel AR.Platelet endothelial cell adhesion molecule (PECAM, CD31) and vascular cell adhesion molecule-1 (VCAM-1, CD106) are essential for leukocyte emigration and diapedesis. PECAM is an essential histologic marker of endothelial cells; VCAM-1 is a prototype marker for endothelial cell activation. In this study, equine PECAM and VCAM mRNA were cloned and sequenced. Both genes are highly conserved amongst several species. This study also revealed conserved structural and regulatory motifs, emphasizing the importance of these genes' physiological roles in immunological responses.
Oleksiewicz MB, Snijder EJ, Normann P.A putative zinc finger (ZF) domain in the Equine arteritis virus (EAV) nsp1 protein was described recently to be required for viral transcription. The nsp1 ZF (50 aa) was expressed on the surface of M13KE gIII phage, fused to the N terminus of the phage pIII protein. To evaluate the functionality of the ZF domain, a binding assay was developed, based on the use of immobilized Ni(2+) ions (Ni-NTA). Phages displaying ZF bound significantly better to Ni-NTA than did phages displaying negative-control peptides, which also contained metal-coordinating residues. Also, binding of ZF-displaying phages...
Tanaka S, Kaji Y, Taniyama H, Matsukawa K, Ochiai K, Itakura C.Typical Pneumocystis carinii pneumonia was found in a male thoroughbred foal (46 days old) suffering from diarrhea and hypogammaglobulinemia after birth. The characteristics of the organisms were demonstrated by Grocott methenamine silver staining, and scanning and transmission electron microscopy. The present focal had no histological lesions suggesting immunodeficiency. However, he could not get adequate colostrum from his dam, because she died of hemorrhagic shock due to immuno-mediated thrombocytopenia at delivery. This condition was considered to have predisposed the foal to the pneumonia...
Radcliffe RM, Bookbinder LC, Liu SY, Tomlinson JE, Cook VL, Hurcombe SDA, Divers TJ.Blood transfusion is a lifesaving treatment for horses with acute hemorrhage and other causes of anemia. Transfusions improve oxygen delivery to the tissues via increased blood volume and hemoglobin concentration. Certain aspects of equine blood transfusion are challenging, especially in the field situation, and practitioners may be unfamiliar or feel overwhelmed with the process. An understanding of the indications, materials, methods, and techniques as well as donor selection and possible complications will help practitioners successfully implement blood transfusion in clinical practice. Met...
Kriegshäuser G, Wutz G, Lea S, Stuart D, Skern T, Kuechler E.Mouse monoclonal antibodies (mAbs) were employed to select neutralization escape mutants of equine rhinitis A virus (ERAV). Amino acid changes in the ERAV mutants resulting in resistance to neutralization were identified in capsid protein VP1 at Lys-114, Pro-240 and Thr-241. Although the changes were located in different parts of the polypeptide chain, these mutants exhibited cross-resistance against all four mAbs employed, indicating that these residues contribute to a single immunogenic site. To explain this result, we constructed a model of the three-dimensional structure of the ERAV capsid...
MacLeay JM.In 1992, a multiparous 13-year-old Thoroughbred mare and her 48-hour-old colt were examined because of possible neonatal isoerythrolysis (NI). Supportive treatment was administered, and the foal recovered without requiring a transfusion. According to the owners, the mare had delivered foals without incident during 1987 and 1991. The mare was barren during 1993, but in 1994, delivered a filly that developed severe NI. The foal was given 3 transfusions and eventually recovered without complications. Blood typing analysis of the mare and its foals indicated that all 4 foals were positive for the ...
Viljoen A, Saulez MN, Donnellan CM, Bester L, Gummow B.Medical records of equine after-hours admissions from 1998 to 2007 are reviewed. Data extracted from the medical records included signalment, reason for admission, pre-admission treatment, clinical presentation, procedures performed, final diagnoses, complications occurring in hospital, length of stay and outcome. Eight hundred and twenty after-hours admissions were available of which 75% were classified as emergencies. Most horses originated from Gauteng province (82%), with Thoroughbred, Arabian, and Warmbloods representing 46%, 10% and 7% of horses. Horses had a median age of 7 years and we...
Abd-Elnaeim MM, Derar IR, Wilsher S, Allen WR, Leiser R, Schuler G.The functions of placental oestrogens during equine pregnancy are still unclear. Yet, they may act predominantly as local regulators of growth and differentiation in the microplacentomes. Thus, expression patterns of oestrogen receptors (ERs) alpha and beta were investigated in the microcotyledonary placenta from pregnant mares at 110, 121, 179, 199 and 309 days of gestation by immunohistochemistry. In microplacentomes, both the ER isoforms were detected in trophoblast (T) cells, chorionic villous stroma (FS), microcaruncular epithelium (ME) and microcaruncular stroma (MS). Proportions of posi...
Cline LJ, Crowle AJ.Evans Blue dye binds selectively, but with different avidities, to five major antigens in human serum. The anodic mobility of the antigen-dye complexes is greater than that of the antigens alone in crossed immunoelectrophoresis, which is of practical value for identification. We used this characteristic to show that in some human sera there is a population of alpha1-lipoprotein molecules that migrates electrophoretically in the beta-lipoprotein region, where in conventional zone electrophoresis it could be mistaken for beta-lipoprotein. We also demonstrate that horses, unlike rabbits, rarely m...
Hisey EA, Martins BC, Donnelly CG, Cassano JM, Katzman SA, Murphy CJ, Thomasy SM, Leonard BC.This study aimed to define the antimicrobial peptide (AMP) expression pattern of the equine ocular surface and amniotic membrane using a targeted qPCR approach and 3'Tag-sequencing. It will serve as a reference for future studies of ocular surface innate immunity and amniotic membrane therapies. Methods: A targeted qPCR approach was used to investigate the presence of orthologs for three of the most highly expressed beta-defensins (DEFB1, DEFB4B, and DEFB103A) of the human ocular surface and amniotic membrane in equine corneal epithelium, conjunctiva, and amniotic membrane. 3'Tag-sequencing wa...
Attili AR, Kennerman E, Takai S, Or ME, Marenzoni ML, Torun S, Pieramati C, Kayar A, Golcu E, Parkan C, Yilmaz Z, Gonul R, Valente C, Cuteri V.In order to assess the Rhodococcus equi infection in three provinces of Turkey (Bursa, Izmir and Istanbul), 696 sera from healthy foals and adult horses were tested by indirect ELISA using a R. equi reference strain (ATCC 6939) as antigen. 103 sera (14.80%) with titres >0.646 resulted positive. Seroprevalence was significantly higher (P=0.0053) in male than in female horses of Istanbul province, although higher antibody titres (mean value) were observed in the female group of Bursa and Izmir provinces with differences estimated between provinces (P=0.0002). Seroprevalence was correlated wit...
Bell SC, Savidge C, Taylor P, Knottenbelt DC, Carter SD.A putative immunodeficiency, causing mortality in UK Fell pony foals (Fell pony syndrome), was studied in affected foals and compared with healthy, age-matched foals. Differential cell counts of peripheral blood indicated that the syndrome foals were lymphopenic (P<0.05). Flow cytometric analysis of circulating leucocytes showed a reduced MHC II expression (P<0.01) on lymphocytes but not on polymorphonuclear cells in affected foals. There were no changes in the percentages of CD4+ or CD8+ T cells. There was an increased (P<0.05) expression of CD11a/18 by the lymphocytes of the syndrom...
Salinas C, Barriga K, Albornoz A, Alarcon P, Quiroga J, Uberti B, Sarmiento J, Henriquez C, Ehrenfeld P, Burgos RA, Moran G.Neutrophils display an array of biological functions including the formation of neutrophil extracellular traps (NETs), web-like structures specialized in trapping, neutralizing, killing and preventing microbial dissemination within the host. However, NETs contribute to a number of inflammatory pathologies, including severe equine asthma. Tamoxifen (TX) is a selective estrogen receptor modulator which belongs to the triphenylethyllenes group of molecules, and which is used as a treatment in all stages of estrogen-positive human breast cancer. Our previous results suggest that tamoxifen can modu...
Piuko K, Bravo IG, Müller M.In the present study we describe the isolation and characterization of putative equine granzyme B for which we propose the designation 'eqGrzmB'. Sequence analysis revealed characteristic features of a GrzmB protease such as the presence of a signal (leader-) peptide and an activation di-peptide. The isolated eqGrzmB is functionally active when expressed in human or in insect cells. Furthermore, exchange of any of three putative active site amino acids, which are highly conserved along granzyme B enzymes, led to a complete loss of enzymatic activity in the newly identified eqGrzmB. Phylogeneti...
