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.
Hébert L, Bidaud P, Goux D, Benachour A, Laugier C, Petry S.Lysozyme is an important and widespread component of the innate immune response that constitutes the first line of defense against bacterial pathogens. The bactericidal effect of this enzyme relies on its capacity to hydrolyze the bacterial cell wall and also on a nonenzymatic mechanism involving its cationic antimicrobial peptide (CAMP) properties, which leads to membrane permeabilization. In this paper, we report our findings on the lysozyme resistance ability of Rhodococcus equi, a pulmonary pathogen of young foals and, more recently, of immunocompromised patients, whose pathogenic capacity...
Teijeiro JM, Marini PE.The oviduct is a dynamic organ in which final gamete maturation, fertilization and early embryo development take place. It is considered to be a sterile site; however the mechanism for sterility maintenance is still unknown. S100A7 is an anti-microbial peptide that has been reported in human reproductive tissues such as prostate, testicle, ovary, normal cervical epithelium and sperm. The current work reports the presence of S100A7 in the Fallopian tube and its localization at the apical surface of epithelial cells. For comparison, porcine S100A7 was used for antibody development and search for...
Pittaway CE, Lawson AL, Coles GC, Wilson AD.Infection of horses with Anoplocephala perfoliata induces a severe inflammatory reaction of the caecal mucosa around the site of parasite attachment adjacent to the ileocecal valve. Lesions show epithelial erosion or ulceration of the mucosa with infiltration by eosinophils, lymphocytes and mast cells leading to oedema, gross thickening and fibrosis of the caecal wall. Despite this evidence of an inflammatory reaction to A. perfoliata within the mucosa of the caecum there is little information about the nature of the local immune response to A. perfoliata. An ELISA which assays serum IgG(T) an...
Sampieri F, Vannucci FA, Allen AL, Pusterla N, Antonopoulos AJ, Ball KR, Thompson J, Dowling PM, Hamilton DL, Gebhart CJ.Lawsonia intracellularis infection causes proliferative enteropathy (PE) in many mammalian species, with porcine and equine proliferative enteropathy (PPE and EPE) known worldwide. Hamsters are a well-published animal model for PPE infection studies in pigs. There is no laboratory animal model for EPE infection studies and it is not known whether there is species-specificity for equine or porcine isolates of L. intracellularis in animal models. The objective of this study was to determine whether it is possible to generate typical EPE lesions in hamsters after inoculation with an equine strain...
Herman EH, Knapton A, Liu Y, Lipshultz SE, Estis J, Todd J, Woodward RA, Cochran T, Zhang J, Poirier MC.Cardiac troponins serve as serum biomarkers of myocardial injury. The current study examined the influence of age on serum concentrations of cardiac troponin I (cTnI). An ultrasensitive immunoassay was used to monitor cTnI concentrations in Sprague-Dawley (SD) rats and Erythrocebus patas monkeys of different ages. The mean cTnI concentrations were highest in 10-day-old rats compared to 25-, 40-, and 80-day-old SD rats. Cardiomyocyte remodeling was apparent in hearts from 10-day-old SD rats as evident by hypercellularity, irregularly shaped nuclei, and moderate numbers of myocytes undergoing mi...
Lohmann KL, Lopez AM, Manning ST, Marques FJ, Brownlie R, Allen AL, Sangster AE, Mutwiri G, Gerdts V, Potter A, Townsend HG.We evaluated the immunogenic and protective potential of a recombinant VapA/CpG oligodeoxynucleotide (ODN) 2395 vaccine in neonatal foals undergoing experimental Rhodococcus equi challenge. Foals (n = 8) were vaccinated by intramuscular injection on days 1 and 15 of the study; control foals (n = 7) received a phosphate-buffered saline (PBS) solution. All foals were challenged by intrabronchial administration of 5 × 10⁶ R. equi 103⁺ on day 29. Bronchoalveolar lavages were done on days 15, 29, and 36 and total cell count, differential cell count, rVapA-stimulated cell proliferation and inte...
Mazzei M, Savini G, Di Gennaro A, Macchioni F, Prati MC, Guzmàn LR, Tolari F.West Nile virus (WNV) is a mosquito-borne virus belonging to the family Flaviviridae included in the Japanese encephalitis antigenic complex (JEAC). A seroepidemiological study was carried out in 2011 using 160 horse sera collected from different areas of Bolivia to investigate the presence of WNV antibody. A high proportion (59.4%) of the tested sera were positive to a commercially available WNV competitive enzyme-linked immunosorbent assay (C-ELISA). Sixty-six randomly selected C-ELISA-positive sera were further tested by WNV plaque reduction neutralization test (PRNT), virus neutralization ...
Szóstek AZ, Lukasik K, Galvão AM, Ferreira-Dias GM, Skarzynski DJ.The aim of the study was to characterize endometrial mRNA transcription, immunolocalization, and protein expression of interleukin (IL) 1alpha, IL1beta, IL6, and IL1RI, IL1RII, and IL6Ralpha/beta in the course of endometrosis during the estrous cycle. Additionally, the influence of IL1alpha, IL1beta, and IL6 on prostaglandin (PG) secretion and PG synthase mRNA transcription in endometrial tissue during endometrosis was investigated. The endometrial samples were obtained at the early (n = 12), mid- (n = 12), and late (n = 12) luteal phases and at the follicular (n = 12) phase of the estrous cyc...
Boudreaux MK, Humphries DM.Platelet alloantigens in horses may play an important role in the development of neonatal alloimmune thrombocytopenia (NAIT). Objective: The objective of this study was to evaluate genes encoding major platelet glycoproteins within the Equidae family in an effort to identify potential alloantigens. Methods: DNA was isolated from blood samples obtained from Equidae family members, including a Holsteiner-Oldenburg cross, a Quarter horse, a donkey, and a Plains zebra (Equus burchelli). Gene sequences encoding equine platelet membrane glycoproteins IIb, IIIa (integrin subunits αIIb and β3), Ia (...
Hyde RM, Lynch TM, Clark CK, Slone DE, Hughes FE.This study investigated the influence of perfusate volume on antimicrobial concentration in synovial fluid following intravenous regional limb perfusion (IVRLP) and assessed the efficacy of low volume IVRLP. The front limbs of 9 horses were randomly assigned to 1 of 3 volume groups: 10 mL (Group 1), 30 mL (Group 2), or 60 mL (Group 3). A tourniquet was applied distal to the carpus and the limbs were perfused with 500 mg genta-micin diluted to the assigned volume via a catheter placed in the lateral palmar digital vein at the level of the proximal sesamoid bones. Synovial fluid samples were col...
Sampieri F, Allen AL, Pusterla N, Vannucci FA, Antonopoulos AJ, Ball KR, Thompson J, Dowling PM, Hamilton DL, Gebhart CJ.The objective of this study was to demonstrate the susceptibility of rabbits to Lawsonia intracellularis obtained from a case of clinical equine proliferative enteropathy (EPE). This is a preliminary step toward developing a rabbit infection model for studying pathogenesis and therapy of EPE in horses. Nine does were equally assigned to 3 groups. Animals in 2 groups (Group 1 and Group 2) were orally inoculated with different doses of cell-cultured L. intracellularis. Controls (Group 3) were sham-inoculated. Feces and blood were collected before the rabbits were infected and at 7, 14, and 21 da...
Biddle AS, Black SJ, Blanchard JL.Laminitis is a chronic, crippling disease triggered by the sudden influx of dietary starch. Starch reaches the hindgut resulting in enrichment of lactic acid bacteria, lactate accumulation, and acidification of the gut contents. Bacterial products enter the bloodstream and precipitate systemic inflammation. Hindgut lactate levels are normally low because specific bacterial groups convert lactate to short chain fatty acids. Why this mechanism fails when lactate levels rapidly rise, and why some hindgut communities can recover is unknown. Fecal samples from three adult horses eating identical di...
Pigott JH, Ishihara A, Wellman ML, Russell DS, Bertone AL.To compare the clinical and inflammatory joint responses to intra-articular injection of bone marrow-derived mesenchymal stem cells (MSC) including autologous, genetically modified autologous, allogeneic, or xenogeneic cells in horses. Methods: Six five-year-old Thoroughbred mares had one fetlock joint injected with Gey's balanced salt solution as the vehicle control. Each fetlock joint of each horse was subsequently injected with 15 million MSC from the described MSC groups, and were assessed for 28 days for clinical and inflammatory parameters representing synovitis, joint swelling, and pain...
Turki I, Hammami A, Kharmachi H, Mousli M.Human and equine rabies immunoglobulins are currently available for passive immunization against rabies. However, these are hampered by the limited supply and some drawbacks. Advances in antibody engineering have led to overcome issues of clinical applications and to improve the protective efficacy. In the present study, we report the generation of a trivalent single-chain Fv (scFv50AD1-Fd), that recognizes the rabies virus glycoprotein, genetically fused to the trimerization domain of the bacteriophage T4 fibritin, termed 'foldon' (Fd). scFv50AD1-Fd was expressed as soluble recombinant protei...
Schnabel CL, Wagner S, Wagner B, Durán MC, Babasyan S, Nolte I, Pfarrer C, Feige K, Murua Escobar H, Cavalleri JM.Research on equine cytokines is often performed by analyses of mRNA. For many equine cytokines an analysis on the actual protein level is limited by the availability of antibodies against the targeted cytokines. Generation of new antibodies is ongoing but time consuming. Thus, testing the reactivity of commercially available antibodies for cross-reactivity with equine cytokines is of particular interest. Fifteen monoclonal antibodies against IL-1β, IL-6, IL-8, IL-12, IL-18 and Granulocyte Macrophage Colony stimulating factor (GM-CSF) of different species were evaluated for reactivity with the...
Pigott JH, Ishihara A, Wellman ML, Russell DS, Bertone AL.Mesenchymal stem cells have demonstrated immunomodulatory capabilities as well as modest efficacy in animal models of joint injury, warranting further study as a potential treatment of joint disease. The goal of the study was to investigate the blood and synovial immune and histologic response to intra-articular injection of autologous, allogeneic, and xenogeneic bone marrow-derived mesenchymal stem cells (MSC) in horses. The study group consisted of 6 five-year-old Thoroughbred mares that had been injected previously with 15 million, genetically modified autologous, allogeneic, or xenogeneic ...
Andruskevich SM, Perry P, Houpt K, Houpt TR.The objectives were to measure changes in fluid balance of mares at parturition and relate those changes to the foals' acquisition of passive immunity. Twelve Thoroughbred mares and their foals were observed for suckling behavior for the first 12h post-partum. The mare's water intake, packed cell volume, plasma protein concentration, and plasma osmolality were measured pre- and post-partum. The foals' immunoglobulin concentrations were measured at birth and 24h later. The median increase from pre- to post-foaling in mares' packed cell volume was 4.0% (interquartile range=0.3-6.8). The median i...
Gildea S, Quinlivan M, Murphy BA, Cullinane A.Previous studies in experimental ponies using interferon gamma (IFN-γ) as a marker for cell mediated immune (CMI) response demonstrated an increase in IFN-γ gene expression following vaccination with an ISCOM subunit, a canarypox recombinant and more recently, an inactivated whole virus vaccine. The objective of this study was to carry out an independent comparison of both humoral antibody and CMI responses elicited following vaccination with all these vaccine presentation systems. Antibody response of 44 Thoroughbred weanlings was monitored for three weeks following the second dose of prima...
Kumar S, Kumar R, Gupta AK, Yadav SC, Goyal SK, Khurana SK, Singh RK.Equine piroplasmosis is a tick-transmitted protozoan disease caused by Theileria equi and/or Babesia caballi. In the present study, we expressed a 53kDa protein from the truncated EMA-2 gene of T. equi (Indian strain) and developed EMA-2ELISA using this expressed protein. This ELISA is able to detect T. equi-specific antibodies in experimentally infected animals as early as 9 days post-infection. The assay developed was validated with the OIE recommended competitive ELISA (cELISA) on 120 serum samples and significant agreement (kappa=0.93) was observed between results of both the ELISAs which ...
Kailaanmäki A, Kinnunen T, Kwok WW, Rytkönen-Nissinen M, Randell J, Virtanen T.The responses of allergen-specific CD4(+) T cells of allergic and healthy individuals are still incompletely understood. Our objective was to investigate the functional and phenotypic properties of CD4(+) T cells of horse-allergic and healthy subjects specific to the immunodominant epitope region of the major horse allergen Equ c 1. Specific T-cell lines (TCLs) and clones were generated from peripheral blood mononuclear cells with Equ c 1(143-160), the peptide containing the immunodominant epitope region of Equ c 1. The frequency, proliferative response, cytokine production and HLA restriction...
Textor JA, Willits NH, Tablin F.Platelet-rich plasma (PRP) products may be useful for treatment of joint disease in horses, but may contain undesirable pro-inflammatory cytokines in addition to growth factors. This study investigated whether autologous PRP increases synovial fluid growth factor and cytokine concentrations when injected into normal equine metacarpophalangeal and metatarsophalangeal (fetlock) joints. Fetlock joints of seven healthy horses received one of four treatments: saline, resting PRP, CaCl2-activated PRP or thrombin-activated PRP. Synovial fluid was sampled prior to injection and at 6, 24, 48 and 96 h p...
Reed SM, Howe DK, Morrow JK, Graves A, Yeargan MR, Johnson AL, MacKay RJ, Furr M, Saville WJ, Williams NM.Recent work demonstrated the value of antigen-specific antibody indices (AI and C-value) to detect intrathecal antibody production against Sarcocystis neurona for antemortem diagnosis of equine protozoal myeloencephalitis (EPM). Objective: The study was conducted to assess whether the antigen-specific antibody indices can be reduced to a simple serum : cerebrospinal fluid (CSF) titer ratio to achieve accurate EPM diagnosis. Methods: Paired serum and CSF samples from 128 horses diagnosed by postmortem examination. The sample set included 44 EPM cases, 35 cervical-vertebral malformation (CVM) ca...
Silva A, Wagner B, McKenzie HC, Desrochers AM, Furr MO.The objectives of this study were to (1) evaluate the effects of equine soluble CD14 (sCD14) and monoclonal antibodies (mAb) to equine CD14 on lipopolysaccharide-induced tumor necrosis factor α (TNF-α) secretion from equine peripheral blood mononuclear cells (PBMC); and to (2) determine serum concentrations of sCD14 in a population of horses with gastrointestinal diseases or other illnesses likely to result in endotoxemia. Equine PBMC isolated from 10 healthy horses were incubated with Escherichia coli LPS plus CD14 mAb or sCD14 and assayed for TNF-α activity. Pre-incubation with CD14 mAb d...
Horsington J, Hartley CA, Gilkerson JR.Respiratory infections are a major burden in the performance horse industry. Equine rhinitis B virus (ERBV) has been isolated from horses displaying clinical respiratory disease, and ERBV-neutralizing antibodies have been detected in 50-80% of horses in reported surveys. Current ERBV isolation and detection methods may underestimate the number of ERBV-positive animals and do not identify multiple serotype infections. The aim of the current study was to develop a serotyping ERBV antibody-detection enzyme-linked immunosorbent assay (ELISA) and examine the seroprevalence of ERBV in a group of Aus...
Ball BA, Scoggin KE, Troedsson MH, Squires EL.Biological effects of prostaglandin E2 are mediated via one of four receptors designated EP1, EP2, EP3 and EP4 which are encoded by separate genes. In general, EP1 and EP3 induce smooth muscle contraction whereas EP2 and EP4 induce smooth muscle relaxation. The objective of the current study was to characterize the expression of the genes for PGE2 receptors (EP2 and EP4) in the horse oviduct based upon immunohistochemistry (IHC) and quantitative PCR (qPCR). Oviductal tissue was collected from mares at estrus (n=5), at 5 days post-ovulation (n=4), and from prepubertal mares (n=5). Isthmic and a...
Choi KS, Ko YJ, Nah JJ, Kim YJ, Kang SY, Yoon KJ, Joo YS.A rapid immunoassay for detecting and quantifying West Nile virus (WNV)-neutralizing antibodies in sera was developed as an alternative to the plaque reduction neutralization test (PRNT), the gold standard test for WNV. The assay is a competitive, enzyme-linked immunosorbent assay using neutralizing monoclonal antibody 5E8 (NT-ELISA). A cutoff percent inhibition (PI) value of 35% (mean PI plus 3 standard deviations), with a specificity of 99%, was established based on analysis of 246 serum samples from horses free of WNV. The NT-ELISA detected neutralizing antibodies in all sera collected 7 or...
Entenfellner J, Gahan J, Garvey M, Walsh C, Venner M, Cullinane A.The international governing body of equestrian sports requires that horses be vaccinated against equine influenza within 6 months and 21 days of competing. The aim of this study was to compare the antibody response of young sport horses to six-monthly booster vaccination with equine influenza vaccines of different formulations. An inactivated vaccine was allocated to 35 horses and subunit and recombinant vaccines were allocated to 34 horses each. After vaccination, all horses were monitored for evidence of adverse reactions. Whole blood samples were collected at the time of vaccination and on ...
Laroucau K, Saqib M, Martin B, Deshayes T, Bertin C, Wernery U, Joseph S, Singha H, Tripathi BN, Beck C.Burkholderia mallei is the etiologic agent of glanders, an infectious disease of solipeds, with renewed scientific interest due to its increasing incidence in different parts of the world. More rapid, sensitive and specific assays are required by laboratories for confirmatory testing of this disease. A microsphere-based immunoassay consisting of beads coated with B. mallei recombinant proteins (BimA, GroEL, Hcp1, and TssB) has been developed for the serological diagnosis of glanders. The proteins' performance was compared with the OIE reference complement fixation test (CFT) and an indirect en...
Visser MB, Pollitt CC.Most research to date involving laminins and extracellular matrix protein function in both normal and pathological conditions involves in vitro culture of keratinocytes. Few methods are established to allow for prolonged propagation of keratinocytes from equine tissues, including the hoof lamellae. In this study we modified cell isolation and culture techniques to allow for proliferation and sub-culturing of equine lamellar keratinocytes. Additionally, the production and processing of extracellular matrix molecules by skin and lamellar keratinocytes were studied. Results: Physical and proteoly...
Delcambre GH, Liu J, Streit WJ, Shaw GPJ, Vallario K, Herrington J, Wenzlow N, Barr KL, Long MT.West Nile virus (WNV), a mosquito borne member of the Flaviviridae, is one of the most commonly diagnosed agents of viral encephalitis in horses and people worldwide. Objective: A cassette of markers for formalin-fixed paraffin-embedded tissue and an archive of tissues from experimental infections in the horse were used to investigate the equine neuroimmune response to WNV meningoencephalomyelitis to phenotype the early response to WNV infection in the horse. Methods: Quantitative analysis using archived tissue from experimentally infected horses. Methods: The thalamus and hindbrain from 2 gro...
Gillespie J, Kalica A, Conner M, Schiff E, Barr M, Holmes D, Frey M.From 105 field cases of diarrhea in neonatal or young foals, rotavirus was detected by electron microscopy (EM) and/or by enzyme-linked immunosorbent assay (ELISA) in the feces of 65 foals on 16 different premises. ELISA was performed with Rotazyme test kits developed by Abbot and Company for the detection of rotaviruses. Twenty-four field isolates from the feces of diarrheic foals with equine rotavirus infection as ascertained by EM were placed in MA-104 cell cultures after pretreatment of the viral suspension with 10 micrograms ml-1 of trypsin and incorporation of 0.5 micrograms ml-1 or 1 mi...
Davis KU, Sheats MK.Mild to moderate equine asthma syndrome (mEAS) affects horses of all ages and breeds. To date, the etiology and pathophysiology of mEAS are active areas of research, and it remains incompletely understood whether mEAS horses with different immune cell 'signatures' on BAL cytology represent different phenotypes, distinct pathobiological mechanisms (endotypes), varied environmental conditions, disease severity, genetic predispositions, or all of the above. In this descriptive study, we compared gene expression data from BAL cells isolated from horses with normal BALF cytology (n = 5), to those i...
Felsburg PJ, Somberg RL, Perryman LE.This review describes the clinical, immunologic and pathologic features of two naturally-occurring models of severe combined immunodeficiency (SCID) in domestic animals that represent different forms of human SCID. Canine X-linked SCID (XSCID) has an X-linked recessive mode of inheritance and, as such, represents a model for the most common form of human SCID in the United States. Affected dogs have normal percentages of circulating B cells and low to normal percentages of phenotypically mature, but nonfunctional T cells. Severe combined immunodeficiency in the horse is an autosomal recessive ...
Paillot R, Kydd JH, MacRae S, Minke JM, Hannant D, Daly JM.Equine influenza virus (EIV) is a leading cause of respiratory disease in horses. Equine influenza infection induces a long-term immunity to re-infection. Recent strategies of vaccination aim to mimic this immunity by stimulating both antibody and cellular immune responses. Cell-mediated immunity (CMI) to influenza is well defined in man, but little has been done to characterise the responses in the horse. Additionally, the development of reliable assays for the measurement of equine CMI has lagged behind serological methods and vaccine development. In this study, two methods of measuring EIV-...
The Journal of parasitologyJanuary 23, 2003
Volume 88, Issue 6 1239-1246 doi: 10.1645/0022-3395(2002)088[1239:QEOSTF]2.0.CO;2
Packham AE, Conrad PA, Wilson WD, Jeanes LV, Sverlow KW, Gardner IA, Daft BM, Marsh AE, Blagburn BL, Ferraro GL, Barr BC.Neospora hughesi is a newly recognized protozoan pathogen in horses that causes a myeloencephalitis similar to Sarcocystis neurona. There are no validated serologic tests using the gold standard sera that are currently available to detect specific N. hughesi antibodies and, thus, no tests available to detect antemortem exposure or estimate seroprevalence in the horse. The objectives of the present study were to establish a bank of gold standard equine sera through experimental infections with N. hughesi and to assess several serologic tests for the detection of related protozoan antibodies. Se...
Anton F, Morales C, Aguilar R, Bellido C, Aguilar E, Gaytán F.The existence of a physiological integration between the immune and endocrine systems has long been recognized. In spite of the abundant literature data on the presence of cells of the immune system in the testis, mast cells and eosinophil leukocytes have received little attention. We have studied the presence, distribution and numbers of mast cells and eosinophils in the testes of 12 mammalian species. Mast cells were frequently found in equine (stallion, ass and mule) and human testis, whereas eosinophils were nearly absent. On the contrary, eosinophils were abundant in the hare testis, whil...
Harris SP, Hines MT, Mealey RH, Alperin DC, Hines SA.Rhodococcus equi is an important respiratory pathogen of young foals for which a vaccine has long been sought. Two major impediments to effective vaccination are the functionally immature type I immune responses of neonatal foals and early exposure to the bacterium via the environment. Despite these obstacles, it appears that under specific circumstances foals can develop a protective immune response. In this study we investigated the protective mechanisms behind oral inoculation of foals with virulent R. equi bacteria. Two foals receiving an oral inoculum demonstrated accelerated development ...
Fairbairn SM, Page CP, Lees P, Cunningham FM.Previous studies have shown that bronchoalveolar lavage fluid from horses with allergic respiratory disease and showing clinical symptoms contains increased numbers of neutrophils. In some cases, the eosinophil count is also increased. In this study the time course of changes in lung function and the accumulation of radiolabelled leucocytes and platelets in the lungs of allergic and normal horses has been examined during a 7 hr allergen exposure. Antigen challenge had no effect on pleural pressure or the distribution of radiolabelled neutrophils, eosinophils or platelets in normal horses. In c...
Werners AH, Bull S, Fink-Gremmels J, Bryant CE.Macrophages play a pivotal role in the pathophysiology of many diseases by mediating the host immune response to infections and intoxications. The species-specific activation of macrophages and the differential response in cytokine production impedes the extrapolation of results between species. Therefore, the aim of this study was to isolate and immortalise macrophages from equine bone marrow (BM) cells in order to study equine-specific signalling pathways. The isolated BM-derived macrophages (referred to as e-CAS cells) showed proliferation kinetics similar to that of standardised cell lines...
Ahn H, Kim J, Lee H, Lee E, Lee GS.Inflammasome, a cytosolic multi-protein complex, assembly is a response to sensing intracellular pathogenic and endogenic danger signals followed by caspase-1 activation, which maturates precursor cytokines such as interleukin (IL)-1β. Most inflammasome research has been undertaken in humans and rodents, and inflammasomes in veterinary species have not been well-characterized. In this study, we observed the effects of well-known inflammasome activators on equine peripheral blood monocytes (PBMCs). The NLRP3 inflammasome triggers include ATP, nigericin, aluminum crystals, and monosodium urate ...
Gibson JS, O'Neill T, Thackray A, Hannant D, Field HJ.Serum antibody (virus neutralisation, complement fixation, IgM and IgG) responses to equine herpesvirus-1 (EHV-1) infection were measured in six foals which were initially free from EHV-1 and EHV-4 infection and maternally-derived antibodies. Following primary infection, high titres of virus neutralisation and complement fixation antibodies were detectable against EHV-1, however, corresponding antibody levels against EHV-4 were low or inapparent, although the two viruses share a number of cross-reactive epitopes. In addition, following the primary infection with EHV-1, IgM levels increased bef...
Braune S, Walter M, Schulze F, Lendlein A, Jung F.For in vitro studies assessing the interaction of platelets with implant materials, common and standardized protocols for the preparation of platelet rich plasma (PRP) are lacking, which may lead to non-matching results due to the diversity of applied protocols. Particularly, the aging of platelets during prolonged preparation and storage times is discussed to lead to an underestimation of the material thrombogenicity. Here, we study the influence of whole blood- and PRP-storage times on changes in platelet morphology and function. Blood from apparently healthy subjects was collected according...
Pezzanite L, Chow L, Griffenhagen G, Dow S, Goodrich L.Culture and expansion of equine mesenchymal stromal cells (MSCs) are routinely performed using fetal bovine serum (FBS) as a source of growth factors, nutrients, and extracellular matrix proteins. However, the desire to minimize introduction of xenogeneic bovine proteins or pathogens and to standardize cellular products intended for clinical application has driven evaluation of alternatives to FBS. Replacement of FBS in culture for several days before administration has been proposed to reduce antigenicity and potentially prolong survival after injection. However, the functional consequences o...
Abbott JB, Mellor DJ, Barrett EJ, Proudman CJ, Love S.The serological changes in two groups of horses known to be harbouring Anoplocephala perfoliata were studied; 12 were treated with 1.5 mg/kg praziquantel and 200 microg/kg ivermectin, and 14 were treated with 200 microg/kg ivermectin. Serological and faecal analyses were carried out on each animal at intervals for 758 days. The titres of antibodies specific for A perfoliata decreased from the day of treatment to day 28 in both groups, and continued to decrease in the group treated with praziquantel and ivermectin, with the first significant decrease from the other group at day 121. From day 15...
Kent JE, Goodall J.Serum haptoglobin was measured by immunoturbidity in Thoroughbreds stabled in three Newmarket yards for nine months. The mean serum haptoglobin value for horses housed in Stable 1 was 1.43 +/- 0.68 g/litre, similar to values in grazing adult ponies. The mean monthly haptoglobin values remained constant. For horses in Stable 2 there was an increase in serum haptoglobin values in June and July whereas, in Stable 3, the increases early in the training season were associated with an increase in serum viral titres. In equine serum, haptoglobin values estimated in g/litre by immunoturbidimetry were ...
Mérant C, Breathnach CC, Kohler K, Rashid C, Van Meter P, Horohov DW.Newborn foals are very susceptible to infections by opportunistic pathogens such as Rhodococcus equi. This susceptibility is thought to be due to the immaturity of their immune system, in particular their inability to produce interferon-gamma. This deficiency may result from an insufficiency in accessory signals. We therefore compared monocyte-derived dendritic cells (MoDC) from foals and from adult horses. CD172, MHC-I and MHC-II were generally expressed on more than 90% MoDC from foals and adults. CD1w2(+)CD86(+) cells tended to be less represented in 2-3-week-old foals than in adults. This ...
Palmer J.Despite advances in neonatal intensive care sepsis, severe sepsis and septic shock remain the biggest killers of neonatal foals. Management of this severe syndrome remains difficult, requiring intensive intervention. Key aspects of management include infection control, hemodynamic support, immunomodulatory interventions, and metabolic/endocrine support. Infection control largely consists of early antimicrobial therapy, plasma transfusions, and local therapy for the infected focus. In cases with severe sepsis or septic shock, hemodynamic support with fluids, vasoactive agents, and respiratory s...
Vychodilova L, Matiasovic J, Bobrova O, Futas J, Klumplerova M, Stejskalova K, Cvanova M, Janova E, Osickova J, Vyskocil M, Sedlinska M, Dusek L....Equine insect bite hypersensitivity (IBH) is a seasonal IgE-mediated dermatosis caused by bites of insects of the genus Culicoides. A familial predisposition for the disease has been shown but, except for the MHC, the genes involved have not been identified so far. An immunogenomic analysis of IBH was performed in a model population of Old Kladruby horses, all living in the same environment. Clinical signs of IBH were used as phenotypic manifestation of IBH. Furthermore, total serum IgE levels were determined in the sera of these horses and used as an independent phenotypic marker for the immu...
Ziegler A, Marti E, Summerfield A, Baumann A.Dendritic cells (DC) are antigen-presenting cells that can be classified into three major cell subsets: conventional DC1 (cDC1), cDC2 and plasmacytoid DCs (pDC), none of which have been identified in horses. Therefore, the objective of this study was to identify and characterize DC subsets in equine peripheral blood, emphasizing on pDC. Surface marker analysis allowed distinction of putative DC subsets, according to their differential expression of CADM-1 and MHC class II. Equine pDC were found to be Flt3(+) CD4(low) CD13(-) CD14(-) CD172a(-) CADM-1(-) MHCII(low). The weak expression of CD4 on...
Boliar S, Stanislawek W, Chambers TM.The hemagglutination inhibition test is used by many diagnostic and surveillance laboratories for detection of antibodies to influenza viruses. It is well known that the hemagglutination inhibition test is affected by nonspecific inhibitors present in equine serum. Several serum treatments are in use to remove these inhibitors, including treatment with kaolin. Discrepant results were observed in the authors' laboratories when using kaolin treatment before testing equine sera for antibodies against equine influenza virus (EIV) subtype-1 (H7N7). It is demonstrated here that kaolin treatment lead...
McGuire TC, Perryman LE, Davis WC.Nine monoclonal antibodies which reacted with equine immunoglobulin (Ig)M and not other equine Ig and serum proteins were prepared. Cells producing antibodies (C 1.9) which precipitated with IgM and bound to staphylococcal protein A were triple-cloned (C 1.9/3.2) and the antibodies further characterized. Monoclonal antibody C 1.9/3.2 reacted with an IgM determinant present on serum IgM from horses of several breeds. Studies with 125I-labeled IgM revealed the presence of this determinant on all IgM molecules. The monoclonal antibody enabled quantitation of IgM in presuckling foal and adult hors...
Donnelly J, Joyner LP, Graham-Jones O, Ellis CP.The incidence of antibodies to Babesia equi and B. caballi in horses in the Royal Stables of His Majesty the Sultan of Oman was assessed by complement fixation (CF) and immunofluorescent antibody (IFA) tests. Two series of samples taken with a 2-year interval, mainly from animals reared in Oman, indicated a stable but high prevalence of antibodies. On the 2 occasions 94.6 and 97.7% respectively were positive to B. equi by IFA and 76.8 and 75.0% were positive by CF. For B. caballi the corresponding percentage figures were lower--67.9 and 40.9 by IFA and 30.4 and 40.9 by CF. A group of animals t...
Rikihisa Y, Wada R, Reed SM, Yamamoto S.The role of the humoral immune response in ehrlichial infection is unknown. Development of neutralizing antibodies during a course of Ehrlichia risticii infection in a pony was examined in vitro by determining the inhibition of E. risticii infection of P388D1 cells in the presence of the sera. The pony experimentally infected with E. risticii developed significant neutralizing activity in the sera by 15 days postinfection when parasitemia started to decline. Neutralizing activity continued to rise after recovery from the disease up to 34 days postinfection at which time the experiment was term...
Lawler DF, Hopkins J, Watson ED.Recent evidence indicates that the cells of the immune system and their large network of secretory products, or cytokines, play an active role in the ovary throughout the oestrous cycle. In the present study, immune cell populations (T and B lymphocytes, macrophages, granulocytes and eosinophils) and expression of major histocompatibility complex (MHC) class II were investigated in corpora lutea from mares in early (days 2-4), mid- (days 7-10) and late (days 12-14) dioestrus, the post-luteolytic phase (days 16-17) and early pregnancy. The number of T lymphocytes within the corpus luteum increa...
Vychodilova-Krenkova L, Matiasovic J, Horin P.The objective of this study was to identify single nucleotide polymorphisms (SNPs) within four functionally related immune response genes in the horse, and to develop genotyping techniques that could be useful for future genomic studies of horse infectious and allergic diseases. The genes analysed were: the lipopolysaccharide (LPS) receptor gene CD14, the toll-like receptor 4 gene TLR4, the gene Cepsilon encoding the IgE heavy chain molecule and the gene FcepsilonR1 alpha coding for the alpha subunit of the IgE receptor molecule. Horse-specific primers amplifying selected gene regions were des...
