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.
Wagner B, Goodman LB, Babasyan S, Freer H, Torsteinsdóttir S, Svansson V, Björnsdóttir S, Perkins GA.Equine herpesvirus type 1 (EHV-1) continues to cause severe outbreaks of abortions or myeloencephalopathy in horses despite widely used vaccination. The aim of this work was to determine the effects of frequent vaccination with an inactivated EHV vaccine on immune development in horses. Fifteen EHV-1 naïve mares were vaccinated a total of 5 times over a period of 8 months with intervals of 20, 60, 90 and 60 days between vaccine administrations. Total antibody and antibody isotype responses were evaluated with a new sensitive EHV-1 Multiplex assay to glycoprotein C (gC) and gD for up to 14 mon...
Mueller RS, Janda J, Jensen-Jarolim E, Rhyner C, Marti E.Allergic diseases in animals are increasingly gaining importance in veterinary practice and as research models. For intradermal testing and allergen immunotherapy, a good knowledge of relevant allergens for the individual species is of great importance. Currently, the knowledge about relevant veterinary allergens is based on sensitization rates identified by intradermal testing or serum testing for allergen-specific IgE; crude extracts are the basis for most evaluations. Only a few studies provide evidence about the molecular structure of (particularly) dust mite, insect and mould allergens in...
Mini-myoglobin (mini-HHMb) is a fragment of horse-heart myoglobin (HHMb) considered to be the prototype of the product encoded by the central exon of the HHMb gene. For this reason, mini-HHMb has been studied extensively showing that carbonylation and oxygenation properties of the ferrous form are similar to those of the full-length protein, while kinetics and thermodynamics of azide binding to the ferric form are significantly different from those of HHMb. To analyze the structure-function relationships in mini-HHMb and the role of conformational fluctuations in ligand accessibility, the mole...
Meulenbroeks C, van der Meide NM, Willemse T, Rutten VP, Tijhaar E.Ponies may suffer from Insect bite hypersensitivity (IBH), an allergic IgE-mediated pruritic skin disorder, induced by allergens from biting midges of the Culicoides spp. Objective: To determine whether recombinant Culicoides obsoletus allergens are able to activate T cells of ponies exposed to C. obsoletus and whether these allergen-specific responses differ between IBH-affected and healthy ponies. Methods: Ten IBH-affected Shetland ponies and 10 age-matched healthy controls taken from the same stables, to ensure similar exposure to midges. Methods: Peripheral blood mononuclear cells (PBMC) w...
McQueen CM, Dindot SV, Foster MJ, Cohen ND.Rhodococcus equi pneumonia is a major cause of morbidity and mortality in neonatal foals. Much effort has been made to identify preventative measures and new treatments for R. equi with limited success. With a growing focus in the medical community on understanding the genetic basis of disease susceptibility, investigators have begun to evaluate the interaction of the genetics of the foal with R. equi. This review describes past efforts to understand the genetic basis underlying R. equi susceptibility and tolerance. It also highlights the genetic technology available to study horses and des...
Gardner AK, Kelly CS, van Eps AW, Burns TA, Watts MR, Belknap JK.In sepsis models, mitogen-activated protein kinases (MAPKs) are reported to incite inflammatory injury to tissues and are purported to be a therapeutic target. Objective: To assess MAPK signalling in lamellae in sepsis-related laminitis (SRL) at different time points after induction of laminitis via carbohydrate overload, and to determine the effect of regional deep hypothermia (RDH) on MAPK signalling. Methods: In vitro study using archived tissue samples. Methods: Lamellar concentrations of MAPKs were assessed in archived lamellar samples from 2 studies: 1) the starch gruel model of SRL with...
Lange-Consiglio A, Accogli G, Cremonesi F, Desantis S.Amniotic epithelial cells (AECs) spontaneously transform into amniotic mesenchymal cells (AMCs) in vitro during cell culture. Glycocalyx was analyzed to identify the glycan pattern in AECs, AMCs and epithelial-mesenchymal transdifferentiated cells (EMTCs). Pure cell cultures were derived using cloned AEC and AMC cell lines obtained by the dilution technique from amniotic membranes. Mesenchymal cells generated by differentiation of clonal epithelial cells were considered transdifferentiated. Immunocytoscreen, in vitro multipotent differentiation and molecular characterization of EMTCs were perf...
Badial PR, Tallmadge RL, Miller S, Stokol T, Richards K, Borges AS, Felippe MJ.Mature B cell neoplasms cover a spectrum of diseases involving lymphoid tissues (lymphoma) or blood (leukemia), with an overlap between these two presentations. Previous studies describing equine lymphoid neoplasias have not included analyses of clonality using molecular techniques. The objective of this study was to use molecular techniques to advance the classification of B cell lymphoproliferative diseases in five adult equine patients with a rare condition of monoclonal gammopathy, B cell leukemia, and concurrent lymphadenopathy (lymphoma/leukemia). The B cell neoplasms were phenotypically...
Laval K, Favoreel HW, Poelaert KC, Van Cleemput J, Nauwynck HJ.Equine herpesvirus type 1 (EHV-1) is a main cause of respiratory disease, abortion, and encephalomyelopathy in horses. Monocytic cells (CD172a(+)) are the main carrier cells of EHV-1 during primary infection and are proposed to serve as a "Trojan horse" to facilitate the dissemination of EHV-1 to target organs. However, the mechanism by which EHV-1 is transferred from CD172a(+) cells to endothelial cells (EC) remains unclear. The aim of this study was to investigate EHV-1 transmission between these two cell types. We hypothesized that EHV-1 employs specific strategies to promote the adhesion o...
Moghtaderi M, Farjadian S, Hosseini Z, Raayat A.The aim of this study has been to investigate the frequency of sensitization to horse allergens and clinical symptoms in horse riders. Methods: A total of 42 horse riders and 50 healthy individuals were examined by means of skin prick tests for a panel of horse and common animal allergens, and pulmonary function tests were done by spirometry. Results: The rate of sensitization to horse allergens was 31% as proven by the skin prick test in horse riders whereas horse sensitization was not seen in the control group. Occupational allergy symptoms were reported by 19 horse riders. Two horse riders ...
Walther S, Rusitzka TV, Diesterbeck US, Czerny CP.Our understanding of how equine immunoglobulin genes are organized has increased significantly in recent years. For equine heavy chains, 52 IGHV, 40 IGHD, 8 IGHJ and 11 IGHC are present. Seven of these IGHCs are gamma chain genes. Sequence diversity is increasing between fetal, neonatal, foal and adult age. The kappa light chain contains 60 IGKV, 5 IGKJ and 1 IGKC, whereas there are 144 IGLV, 7 IGLJ, and 7 IGLC for the lambda light chain, which is expressed predominantly in horses. Significant transcriptional differences for IGLV and IGLC are identified in different breeds. Allotypic and allel...
Nautscher N, Bauer A, Steffl M, Amselgruber WM.This study described corneal morphology in different domestic animals using histological and immunohistochemical methods. Specifically, we evaluated the species-specific distribution pattern of cytokeratins (CKs) and aquaporins (AQPs) to assess their contribution to the strength and transparency of the cornea, respectively. Methods: Corneal sections (2 μm thick) were obtained from 28 pigs, 11 cows, two goats, six horses, four dogs, and five cats and stained with hematoxylin-eosin and periodic acid-Schiff (PAS) reaction. Immunohistochemistry was also performed using CK1 to 3 and AQP1 and 5 an...
Niedzwiedz A, Jaworski Z, Kubiak K.Equine recurrent airway obstruction (RAO), also known as heaves, is one of the most common respiratory problems in older horses. When RAO-affected horses stay pastured or in a dust-free environment for a prolonged time, clinical signs as well as airway inflammation wane. A number of environmental, immunologic, infectious, and genetic factors play an important role in the pathogenesis of RAO, and the immunologic basis of this disease is still poorly understood. Objective: The aim of this study was to investigate the concentrations of allergen-specific IgE in the serum of horses suffering from R...
de Souza MV, Silva MB, Pinto Jde O, Lima MB, Crepaldi J, Lopes GF, dos Santos HB, Ribeiro RI, Thomé RG.This study evaluated the immunohistochemical expression of type I (COL I) and III (COL III) collagens during the healing process of skin treated with leukocyte-poor platelet-rich plasma (LP-PRP). Seven healthy gelding crossbred horses aged 16 to 17 years were used. Two rectangle-shaped wounds were created surgically in the right and left gluteal regions. Twelve hours after wound induction, 0.5 mL of the LP-PRP was administered in each edge of the wounds of one of the gluteal regions. The contralateral region was used as control (CG). Three samples were obtained: after wound induction (T0), 1...
Olofsson KM, Hjertner B, Fossum C, Press CM, Lindberg R.Inflammatory bowel disease (IBD) in horses is an idiopathic disorder, encompassing different types of chronic intestinal inflammation. The pathogenesis of the disease remains to be established, but it has been suggested that an imbalance between regulatory T cells (Tregs) and T helper 17 (Th17)-associated cytokines and altered toll-like receptor 4 (TLR4) expression is associated with intestinal inflammation in other species. The aim of the present study was to quantify Tregs in rectal biopsies from horses affected with IBD by immunohistochemistry and to evaluate expression of genes encoding in...
Malalana F, Stylianides A, McGowan C.Equine recurrent uveitis (ERU) is a spontaneous disease characterised by repeated episodes of intraocular inflammation. The epidemiology of ERU has not been fully elucidated, but the condition appears to be much more common in horses than is recurrent uveitis in humans, especially in certain breeds and geographical regions. Both humans and horses show a similarly altered immune response and a marked autoimmune response as the primary disease pathophysiology. However, an inciting cause is not always clear. Potential inciting factors in horses include microbial agents such as Leptospira spp. Mic...
Nielsen MK, Scare J, Gravatte HS, Bellaw JL, Prado JC, Reinemeyer CR.Strongylus vulgaris is the most pathogenic nematode parasite of horses. Its extensive migration in the mesenteric blood vessels can lead to life-threatening intestinal infarctions. Recent work has shown that this parasite is still identified among managed horse populations. A serum enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of migrating larvae of S. vulgaris. Previous work has documented an increase in ELISA values following larvicidal treatment with ivermectin and suggested that the target parasite antigen is primarily produced by the later larval stages. T...
Marti E, Wang X, Jambari NN, Rhyner C, Olzhausen J, Pérez-Barea JJ, Figueredo GP, Alcocer MJ.Insect bite hypersensitivity (IBH) is a seasonal recurrent skin allergy of horses caused by IgE-mediated reactions to allergens present in the saliva of biting insects of the genus Culicoides, and possibly also Simulium and Stomoxys species. In this work we show that protein microarrays containing complex extracts and pure proteins, including recombinant Culicoides allergens, can be used as a powerful technique for the diagnosis of IBH. Besides the obvious advantages such as general profiling and use of few microliters of samples, this microarray technique permits automation and allows the gen...
Passamonti F, Veronesi F, Cappelli K, Capomaccio S, Reginato A, Miglio A, Vardi DM, Stefanetti V, Coletti M, Bazzica C, Pepe M.Lyme borreliosis (LB) is a multi-systemic tick-borne disease affecting both humans and animals, including horses, and is caused by a group of interrelated spirochetes classified within the Borrelia burgdorferi sensu lato (s.l.) complex. Despite the high reported seroprevalence in the European equine population for B. burgdorferi s.l., to-date no documented clinical cases have been described. A 6-year-old Paint gelding was referred with a history of three weeks of fever, intermittent lameness and digital flexor tendon sheath effusion of the right hind limb. Based on a strict diagnostic protocol...
Mählmann K, Feige K, Juhls C, Endmann A, Schuberth HJ, Oswald D, Hellige M, Doherr M, Cavalleri JM.Equine melanoma has a high incidence in grey horses. Xenogenic DNA vaccination may represent a promising therapeutic approach against equine melanoma as it successfully induced an immunological response in other species suffering from melanoma and in healthy horses. In a clinical study, twenty-seven, grey, melanoma-bearing, horses were assigned to three groups (n = 9) and vaccinated on days 1, 22, and 78 with DNA vectors encoding for equine (eq) IL-12 and IL-18 alone or in combination with either human glycoprotein (hgp) 100 or human tyrosinase (htyr). Horses were vaccinated intramuscularl...
Sherwood JA, Brittain DC, Howard JJ, Oliver J.Eastern equine encephalitis diagnostic serum antibody can appear 6 days after the onset of symptoms, and its numbers can increase 4-fold in 4 days, arguing for early and frequent serum testing. In populations where cerebrospinal fluid viral nucleic acid testing sensitivity and specificity remain undetermined, cerebrospinal antibody testing should also be performed.
van de Water SG, van Gennip RG, Potgieter CA, Wright IM, van Rijn PA.African horse sickness virus (AHSV) is a virus species in the genus Orbivirus of the family Reoviridae. There are nine serotypes of AHSV showing different levels of cross neutralization. AHSV is transmitted by species of Culicoides biting midges and causes African horse sickness (AHS) in equids, with a mortality rate of up to 95% in naive horses. AHS has become a serious threat for countries outside Africa, since endemic Culicoides species in moderate climates appear to be competent vectors for the related bluetongue virus (BTV). To control AHS, live-attenuated vaccines (LAVs) are used in Afri...
Falomo ME, Ferroni L, Tocco I, Gardin C, Zavan B.Endometriosis is a degenerative process due to a chronic inflammatory damage leading to extracellular matrix components deposition and glandular fibrosis. It is known that mesenchymal stem cells secrete a wide range of bioactive molecules, some of them modulating the immune inflammatory response, and others providing regeneration and remodeling of injured tissue. We have performed in vitro experiments in order to analyze the capability of allogenic equine adipose-derived stem cells (ADSCs) to infiltrate mares' endometrial tissues and to stimulate the expression of cytokines and metallopeptidas...
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)...
Laskoski LM, Locatelli-Dittrich R, Valadão CA, Deconto I, Gonçalves KA, Montiani-Ferreira F, Brum JS, de Brito HF, de Sousa RS.The present study was aimed at identifying laminar lesions and leukocyte infiltration in hoof laminar tissue of horses with colic syndrome and its correlation with the total leukocyte count before death. Six healthy horses were used as control group (CG), and eighteen horses with lethal gastrointestinal disease were divided into two groups: leukopenic group (LG) with seven leukopenic horses, and non-leukopenic group (NLG) with 11 horses with total leukocyte count within reference range for the species. Leukocyte infiltration was examined by immunohistochemistry. Laminar lesions were observed i...
Ríos DL, López C, Carmona JU.The aims were as follows: (1) to evaluate the effects at 48 and 96 h of two concentrations (25 and 50%) of leukocyte and platelet-rich gel (L-PRG) and pure PRG (P-PRG) supernatants on the production/degradation in normal equine synovial membrane explants (SME) of platelet derived growth factor isoform BB, transforming growth factor beta-1, tumor necrosis factor alpha, interleukin (IL-) 4 (IL-4), IL-1 receptor antagonist (IL-1ra), and hyaluronan (HA) synthesis and (2) to correlate these molecules with their respective PRG supernatant treatments. SME from 6 horses were cultured for 96 h with...
Mählmann K, Feige K, Juhls C, Endmann A, Schuberth HJ, Oswald D, Hellige M, Doherr M, Cavalleri JM.Equine melanoma has a high incidence in grey horses. Xenogenic DNA vaccination may represent a promising therapeutic approach against equine melanoma as it successfully induced an immunological response in other species suffering from melanoma and in healthy horses. In a clinical study, twenty-seven, grey, melanoma-bearing, horses were assigned to three groups (n = 9) and vaccinated on days 1, 22, and 78 with DNA vectors encoding for equine (eq) IL-12 and IL-18 alone or in combination with either human glycoprotein (hgp) 100 or human tyrosinase (htyr). Horses were vaccinated intramuscularly, a...
Herd HR, Sula MM, Starkey LA, Panciera RJ, Johnson EM, Snider TA, Holbrook TC.This report describes 2 genetically related paint mares, case Nos. 1 and 2, presented to the Oklahoma State University Boren Veterinary Medical Teaching Hospital for chronic weight loss and abnormal gait, respectively. Notable findings in both cases included marked persistent eosinophilia and multiple intramuscular lateral thoracic masses. Histologic examination of masses revealed eosinophilic, centrally necrotic granulomas and marked eosinophilic myositis. Granulomas in case No. 1 also contained intralesional Sarcocystis sp material, and adjacent muscle fibers contained intact protozoal cysts...
Schauer M, Kleinwort KJH, Degroote RL, Wiedemann C, Kremmer E, Hauck SM, Deeg CA.The GTP-binding protein septin 7 is involved in various cellular processes, including cytoskeleton organization, migration and the regulation of cell shape. Septin 7 function in lymphocytes, however, is poorly characterized. Since the intracellular signaling role of septin 7 is dependent on its interaction network, interaction proteomics was applied to attain novel knowledge about septin 7 function in hematopoietic cells. Our previous finding of decreased septin 7 expression in blood-derived lymphocytes in ERU, a spontaneous animal model for autoimmune uveitis in man, extended the role of sept...
Lunn DP, Holmes MA, Duffus WP.The aim of this study was to produce monoclonal antibodies (mAb) recognizing equine lymphocyte surface antigens. Fusions were conducted using BALB/c mice hyperimmunized with equine thymocytes. Hybridoma supernatants were screened by flow cytometry and positive hybridomas were cloned twice by limiting dilution. These mAb were then characterized for tissue distribution by immunohistology and flow cytometry, and by precipitation and analysis of the lymphocyte antigens which they recognized. Three mAb (CVS5, CVS4 and CVS8) are described which recognize only T lymphocytes in peripheral blood. Two-c...
Tanaka T, Otoguro T, Yamashita A, Kasai H, Fukuhara T, Matsuura Y, Moriishi K.The 5' untranslated region (UTR) of hepatitis C virus (HCV), which is composed of four domains (I, II, III, and IV) and a pseudoknot, is essential for translation and viral replication. Equine nonprimate hepacivirus (EHcV) harbors a 5' UTR consisting of a large 5'-terminal domain (I); three additional domains (I', II, and III), which are homologous to domains I, II, and III, respectively, of HCV; and a pseudoknot, in the order listed. In this study, we investigated the roles of the EHcV 5' UTR in translation and viral replication. The internal ribosome entry site (IRES) activity of the EHcV 5'...
Duarte PC, Daft BM, Conrad PA, Packham AE, Gardner IA.A serum indirect fluorescent antibody test (IFAT) was compared with a Western blot (WB) and a modified Western blot (mWB) for diagnosis of equine protozoal myeloencephalitis (EPM). Using receiver-operating characteristic (ROC) analysis, the area under the curve of the IFAT was greater than the areaunder the curves of the WB and the mWB (P = 0.025 and P = 0.044, respectively). There was no statistically significant difference between the areas under the curves of the WBs (P > 0.05). On the basis of an arbitrarily chosen cut-off titer for a positive test result of 1:80 for the IFAT and interpret...
Benton CV, Brown BL, Harshman JS, Gilden RV.Equine infectious anemia virus (EIAV) was successfully inoculated onto cell cultures of canine and feline origin, resulting in chronic infections in these cultures. Infection of equine cell cultures, which were the previous sole in vitro source demonstrated for virus production, was also performed for comparative purposes. Determination of the nature of the virus produced in the heterologous as well as the equine cells was accomplished in several ways. SDS-PAGE of purified virus from the different cell lines indicated very similar protein composition. Immunological identity was observed in gel...
Heller MC, Drew CP, Jackson KA, Griffey S, Watson JL.Rhodococcus equi is a facultative intracellular bacterial pathogen of foals and immunocompromised humans that infects and proliferates within host macrophages and dendritic cells (DC). Indoleamine 2,3-dioxygenase (IDO), the initial enzyme in the tryptophan catabolism pathway, is upregulated in R. equi infected equine monocyte-derived DC and alveolar macrophages. Tryptophan requirement of R. equi for extracellular and intracellular growth was assessed. Growth of R. equi in minimal media did not require tryptophan and pharmacologic inhibition of IDO had no effect on intracellular proliferation o...
Florindo HF, Pandit S, Gonçalves LM, Videira M, Alpar O, Almeida AJ.Strangles is an infectious disease caused by Streptococcus equi subspecies equi that affects the upper respiratory tract of the Equidae. The control of this disease seems to be dependent on its earlier detection and prevention, but prolonged animal protection without development of strong and severe side effects has not yet been achieved. Convalescent horses exhibit a protective immune response, mainly against SeM (58 kDa), an antiphagocytic and opsonogenic S. equi M-like protein, known as the major protective antigen against strangles. Purified recombinant SeM and S. equi protein extract-entr...
Zhao S, Smits C, Schuurman N, Barnum S, Pusterla N, Kuppeveld FV, Bosch BJ, Maanen KV, Egberink H.Equine coronavirus (ECoV) is considered to be involved in enteric diseases in foals. Recently, several outbreaks of ECoV infection have also been reported in adult horses from the USA, France and Japan. Epidemiological studies of ECoV infection are still limited, and the seroprevalence of ECoV infection in Europe is unknown. In this study, an indirect enzyme-linked immunosorbent assay (ELISA) method utilizing ECoV spike S1 protein was developed in two formats, and further validated by analyzing 27 paired serum samples (acute and convalescent sera) from horses involved in an ECoV outbreak and 1...
McWilliam HE, Nisbet AJ, Dowdall SM, Hodgkinson JE, Matthews JB.Parasitic nematodes of the group Cyathostominae are an important cause of disease in horses. This group consists of approximately 50 species, all of which have similar life cycles that involve encystment of larval stages in the large intestinal wall. Encysted larvae can persist for months to years and, occasionally, large numbers can accumulate and emerge synchronously to cause severe pathology, resulting in diarrhoea, weight loss, colic and/or oedema. This syndrome, known as larval cyathostominosis, can be fatal in up to 50% of cases, despite treatment. There is no diagnostic method that enab...
Benbarek H, Deby-Dupont G, Caudron I, Grülke S, Deby C, Lamy M, Serteyn D.In horses, the mechanisms of lipopolysaccharide (LPS) stimulation of isolated neutrophils to produce reactive oxygen species remain unknown. We re-investigated this problem by monitoring the luminol-enhanced chemiluminescence (CL) produced by LPS-stimulated equine neutrophils. The neutrophils were isolated from horse blood by discontinuous density gradient centrifugation (> or = 99% neutrophils; viability > or = 98%). Increasing concentrations of Escherichia coli (E. coli) LPS (from 0.01-10 microg ml(-1)) were used to activate the neutrophils. When LPS was used directly, without another ...
Moriyama H, Kasashima Y, Kuwano A, Wada S.To identify morphologically the locations of equine corneal epithelial stem cells (CESCs) and to culture these cells. Methods: We studied the eyes of 12 adult thoroughbred horses. Methods: Eye tissues were immunostained for two positive stem cell markers (p63, CK14) and one negative marker (CK3) to identify the locations of CESCs, so we could compare their immunostaining patterns with those of human stem cells previously reported. We compared the proliferation rates and morphological features of epithelial cells isolated from the corneal limbus and central cornea. Results: Undifferentiated cel...
Yan W, Saleem MH, McDonough P, McDonough SP, Divers TJ, Chang YF.Leptospira immunoglobulin (Ig)-like (Lig) proteins are a novel family of surface-associated proteins in which the N-terminal 630 amino acids are conserved. In this study, we truncated the LigA conserved region into 7 fragments comprising the 1st to 3rd (LigACon1-3), 4th to 7.5th (LigACon4-7.5), 4th (LigACon4), 4.5th to 5.5th (LigACon4.5-5.5), 5.5th to 6.5th (LigACon5.5-6.5), 4th to 5th (LigACon4-5), and 6th to 7.5th (LigACon6-7.5) repeat domains. All 7 recombinant Lig proteins were screened using a slot-shaped dot blot assay for the diagnosis of equine leptospirosis. Our results showed that Li...
de Laat MA, Kyaw-Tanner MT, Nourian AR, McGowan CM, Sillence MN, Pollitt CC.Metalloproteinases have been implicated in the pathogenesis of equine laminitis and other inflammatory conditions, through their role in the degradation and remodelling of the extracellular matrix environment. Matrix metalloproteinases (MMPs) and their inhibitors are present in normal equine lamellae, with increased secretion and activation of some metalloproteinases reported in horses with laminitis associated with systemic inflammation. It is unknown whether these enzymes are involved in insulin-induced laminitis, which occurs without overt systemic inflammation. In this study, gene expressi...
Leigh JA, Hodgkinson SM, Lincoln RA.The activation of plasminogen and the binding of plasmin by bacteria may have many effects which promote infection. The occurrence of such activities in streptococci is well documented; however, these are yet to be demonstrated for S. dysgalactiae. Consequently, the ability of this bacterium to activate mammalian plasminogen and bind either plasmin or its zymogen was investigated. Activation of bovine plasminogen was dependent on both the strain and the growth medium used for cultivation. Eighteen strain were able to activate bovine and ovine plasminogen and some of these also activated plasmi...
Scott S, Molesti E, Temperton N, Ferrara F, Böttcher-Friebertshäuser E, Daly J.Standard assays used for influenza serology present certain practical issues, such as inter-laboratory variability, complex protocols and the necessity for handling certain virus strains in high biological containment facilities. In an attempt to address this, avian and human influenza HA pseudotyped retroviruses have been successfully employed in antibody neutralization assays. In this study we generated an equine influenza pseudotyped lentivirus for serological screening. This was achieved by co-transfection of HEK293T cells with plasmids expressing the haemagglutinin (HA) protein of an H3N8...
Naveed A, Eertink LG, Wang D, Li F.Humans and equines are two dead-end hosts of the mosquito-borne West Nile virus (WNV) with similar susceptibility and pathogenesis. Since the introduction of WNV vaccines into equine populations of the United States of America (USA) in late 2002, there have been only sporadic cases of WNV infection in equines. These cases are generally attributed to unvaccinated and under-vaccinated equines. In contrast, due to the lack of a human WNV vaccine, WNV cases in humans have remained steadily high. An average of 115 deaths have been reported per year in the USA since the first reported case in 1999. ...
Burka JF, Deline TR, Holroyde MC, Eyre P.Horses were sensitized to bovine plasma in Freund's complete adjuvant. Leukocytes, separated from venous blood, yielded histamine upon incubation with bovine plasma. Ioslated lung fragments incubated with bovine plasma liberated histamine and 5-HT, but not SRS-A. Pulmonary veins obtained from the same animals contracted to histamine, 5-HT and to antigen (Schultz-Dale reaction). Histamine and 5-HT probably contribute to immediate-type hypersensitivity in horses whereas the role of SRS-A is not proved.
Verma A, Matsunaga J, Artiushin S, Pinne M, Houwers DJ, Haake DA, Stevenson B, Timoney JF.Screening of an expression library of Leptospira interrogans with eye fluids from uveitic horses resulted in identification of a novel protein, LruC. LruC is located in the inner leaflet of the leptospiral outer membrane, and an lruC gene was detected in all tested pathogenic L. interrogans strains. LruC-specific antibody levels were significantly higher in eye fluids and sera of uveitic horses than healthy horses. These findings suggest that LruC may play a role in equine leptospiral uveitis.
Lunn DP, McClure JT, Schobert CS, Holmes MA.Severe combined immunodeficiency (SCID) is a fatal autosommal disease of Arabian horses that leads to failure of maturation of T- and B-lymphocyte populations, although natural killer (NK) cells are unaffected. Thymic and lymph node tissues from two foals suffering from SCID were examined in an immunohistological study using a panel of monoclonal antibodies recognising equine leucocyte differentiation antigens. In both foals, the majority of cells in lymphoid tissues had an EqCD3-EqCD4-EqCD8+ phenotype, although rare EqCD3+ cells were also detected. The EqCD3-EqCD4-EqCD8+ cells may represent a...
Granstrom DE, Alvarez O, Dubey JP, Comer PF, Williams NM.Schizonts of Sarcocystis neurona were identified microscopically in hematoxylin-eosin-stained spinal cord sections from 2 native Panamanian horses that exhibited clinical signs of equine protozoal myelitis (EPM). Spinal cord homogenate from a third Panamanian horse with EPM was inoculated onto monolayers of cultured bovine monocytes (M617). Intracytoplasmic schizonts containing merozoites arranged in rosette forms surrounding a central residual body first were observed 13 wk postinoculation. Parasites divided by endopolygeny and lacked rhoptries. Schizonts from each horse reacted with Sarcocys...
Kydd JH, Hannant D, Mumford JA.This study characterised bronchoalveolar leucocytes collected by lavage from five susceptible and two immune ponies before and after nebulised aerosol infection with equid herpesvirus-1 (EHV-1). Leucocyte counts and lymphocyte phenotypic analyses were performed using either differential staining or an indirect immunofluorescence assay with monoclonal antibodies specific for equine (Eq) CD4, CD5, CD8 and B lymphocytes. After EHV-1 infection, significant changes developed: a transient neutrophilia occurred on Day 2, coincident with a reduction in macrophage numbers and an EqCD5+, EqCD4+ and EqCD...
Gressler AE, Lübke S, Wagner B, Arnold C, Lohmann KL, Schnabel CL.Equine asthma (EA) is a highly relevant disease, estimated to affect up to 20% of all horses, and compares to human asthma. The pathogenesis of EA is most likely immune-mediated, yet incompletely understood. To study the immune response in the affected lower airways, mixed leukocytes were acquired through bronchoalveolar lavage (BAL) and the cell populations were analyzed on a single-cell basis by flow cytometry (FC). Samples of 38 horses grouped as respiratory healthy or affected by mild to moderate (mEA) or severe EA (sEA) according to their history, clinical signs, and BAL cytology were ana...
Laing G, Christley R, Stringer A, Aklilu N, Ashine T, Newton R, Radford A, Pinchbeck G.Pathogens are frequently implicated in equine respiratory disease. In Ethiopia, respiratory disease is a frequent cause for presentation at veterinary clinics and a priority concern for users of working horses. However, there is little existing literature on possible aetiologies. Objective: Determine prevalence of respiratory signs and exposure to major respiratory pathogens through a serological survey. Methods: Cross-sectional. Methods: Systematically selected horses from 19 sites in central Ethiopia were examined clinically and sampled once (August-December 2013). A face-to-face interview c...
Rocha JN, Dangott LJ, Mwangi W, Alaniz RC, Bordin AI, Cywes-Bentley C, Lawhon SD, Pillai SD, Bray JM, Pier GB, Cohen ND.Prescottella equi (formerly Rhodococcus equi) is a facultative intracellular bacterial pathogen that causes severe pneumonia in foals 1-6 months of age, whereas adult horses are highly resistant to infection. We have shown that vaccinating pregnant mares against the conserved surface polysaccharide capsule, β-1 → 6-linked poly-N-acetyl glucosamine (PNAG), elicits opsonic killing antibody that transfers via colostrum to foals and protects them against experimental infection with virulent. R. equi. We hypothesized that equine IgG might be more important than IgG for mediating protection...
van der Meulen KM, Favoreel HW, Pensaert MB, Nauwynck HJ.Equine herpesvirus (EHV)-1 is a pathogen of horses, well known for its ability to induce abortion and nervous system disorders. Clinical signs may occur despite the presence of a virus-specific immune response in the horse. The current review will summarize the research, on how, EHV-1-infected cells can hide from recognition by the immune system. Research findings on immune evasion of EHV-1 will be compared with those of other herpesviruses of veterinary importance.
Barbosa Costa G, Marinho PES, Vilela APP, Saraiva-Silva AT, Crispim APC, Borges IA, Dutra AGS, Lobato ZIP, Dos Reis JKP, de Oliveira DB, Drumond BP....Saint Louis encephalitis virus (SLEV) is a mosquito-borne flavivirus that occurs throughout the Americas, and is considered a public health threat. In Brazil, SLEV has been detected from human cases associated with dengue-like disease, but no neurological symptoms were reported. Furthermore, the epidemiology of SLEV in human populations is still poorly explored in the country. We reported serological and molecular detection of SLEV in a healthy population of equids and humans from rural areas in Southeast Brazil. A plaque reduction neutralization test was applied, and neutralizing antibodies w...
