The immune system in horses is a complex network of cells, tissues, and organs that work together to protect the body from pathogens, such as bacteria, viruses, and parasites. This system includes both innate and adaptive immune responses, which function to identify and eliminate foreign invaders. The innate immune response provides an immediate, non-specific defense, while the adaptive immune response involves a more targeted and long-lasting protection through the production of antibodies. Key components of the equine immune system include white blood cells, such as lymphocytes and macrophages, as well as various signaling molecules like cytokines. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and regulation of the immune system in horses, with an emphasis on understanding its role in maintaining equine health and its response to diseases.
Ammons DT, Chow L, Goodrich L, Bass L, Larson B, Williams ZJ, Stoneback JW, Dow S, Pezzanite LM.Osteoarthritis (OA) is a major source of pain and disability worldwide. Understanding of disease progression is evolving, but OA is increasingly thought to be a multifactorial disease in which the innate immune system plays a role in regulating and perpetuating low-grade inflammation. The aim of this study was to enhance our understanding of OA immunopathogenesis through characterization of the transcriptomic responses in OA joints, with the goal to facilitate the development of targeted therapies. Unassigned: Single-cell RNA sequencing (scRNA-seq) was completed on cells isolated from the syno...
Craig NM, Munguia NS, Trujillo AD, Chan AM, Wilkes R, Dorr M, Marsella R.This study investigated the effects of recombinant equine IL-31 (eIL-31) in vivo and in vitro. Methods: Equine IL-31 mRNA sequences were verified by sequencing. Recombinant eIL-31 was produced using mammalian and bacterial expression systems. From November 2019 through February 2021, 12 normal horses, 6 to 10 years old with no history or clinical signs consistent with allergic skin disease, were injected ID with eIL-31 and saline in 2 challenge studies. Pruritus-associated behaviors were recorded for a minimum of 15 minutes preinjection and 4 hours postinjection. Adherent monocytes from 3 prur...
In this paper, we report a comprehensive and consistent annotation of the locus encoding the β-chain of the equine T-cell receptor (TRB), as inferred from recent genome assembly using bioinformatics tools. The horse TRB locus spans approximately 1 Mb, making it the largest locus among the mammalian species studied to date, with a significantly higher number of genes related to extensive duplicative events. In the region, 136 TRBV (belonging to 29 subgroups), 2 TRBD, 13 TRBJ, and 2 TRBC genes, were identified. The general genomic organization resembles that of other mammals, with a V cluster o...
Holmes CM, Wagner B.Equine herpesvirus type 1 (EHV-1) enters through the upper respiratory tract (URT). Mucosal immunity at the URT is crucial in limiting viral infection and morbidity. Here, intranasal immune cells were collected from horses (n = 15) during an experimental EHV-1 infection. CD4+ and CD8+ T cells were the major intranasal cell populations before infection and increased significantly by day six and fourteen post-infection, respectively. Nasal mucosal T cells were further characterized in healthy horses. Compared to peripheral blood mononuclear cells (PBMC), mucosal CD8+ T-cell percentages were elev...
Malsa J, Reigner F, Riou M, Gesbert A, Guégnard F, Perrot N, Serreau D, Fleurance G, Sallé G.The increasing emergence of anthelmintic-resistant parasitic isolates prompts us to reassess the management of intestinal strongylosis in horses. Additionally, societal demand is shifting toward reducing the use of chemical treatments, aligning with environmentally-friendly practices and the exploration of natural alternatives. In this context, we provide an initial view of the antiparasitic activity and the effect on immune circulating blood cells of three commercialized plant-based feed additives in ponies. Three treatments, based either on mugwort (Artemisia vulgaris), echinacea (Echinacea ...
Samuels A, Burns TA.Lymphoma and myeloproliferative diseases in horses are relatively uncommon. The clinical signs, prognosis, and treatment options depend upon the anatomic location and subtype. Significant gaps in knowledge remain regarding prevalence, pathogenesis of different subtypes, antemortem diagnostic tests, response to treatment, and standardized treatment protocols. However, treatment options are available, accessible on the farm, and could improve quality of life and prolong survival.
Fedorka CE, El-Sheikh-Ali H, Scoggin KE, Coleman S, Humphrey EA, Troutt L, Troedsson MHT.The establishment of pregnancy involves a fine-tuned balance between protection and tolerance within the maternal immune system, as the female needs to accept a foreign antigen (the semi-allogenic fetus) while still being able to combat pathogens from the uterus. In the horse, the first uterine exposure to paternal antigens is during mating when sperm is introduced to the tissue and draining lymphatics of the uterus. Additionally, it has been suggested that seminal plasma and its proteins within it play an essential role in preparing the female tract for a suitable immunologic environment but ...
Hobbs KJ, Bayless R, Sheats MK.With the emergence of COVID-19, there is an increased focus in human literature on cytokine production, the implications of cytokine overproduction, and the development of novel cytokine-targeting therapies for use during sepsis. In addition to viral infections such as COVID-19, bacterial infections resulting in exposure to endotoxins and exotoxins in humans can also lead to sepsis, resulting in organ failure and death. Like humans, horses are exquisitely sensitive to endotoxin and are among the veterinary species that develop clinical sepsis similar to humans. These similarities suggest that ...
Preston JF, Mustikka MP, Priestnall SL, Dunkel B, Fischer MC.There is limited literature regarding equine immune mediated keratitis (IMMK) in Europe. North America-based publications describe minimal blepharospasm, rare corneal ulceration and no uveitis; clinical impression suggests these are seen in Europe. Objective: Assess the prevalence of blepharospasm, corneal ulceration and uveitis and their impact on outcome in horses diagnosed with IMMK in Europe (UK and Finland). Methods: Retrospective case series. Methods: Clinical records of 94 horses with IMMK were evaluated. The UK and Finland populations were comparable; therefore, descriptive statistics ...
Laseca N, Molina A, Perdomo-González D, Ziadi C, Azor PJ, Valera M.Vitiligo is a depigmentation autoimmune disorder characterized by the progressive loss of melanocytes leading to the appearance of patchy depigmentation of the skin. The presence of vitiligo in horses is greater in those with grey coats. The aim of this study was therefore to perform a genome-wide association study (GWAS) to identify genomic regions and putative candidate loci associated with vitiligo depigmentation and susceptibility in the Pura Raza Español population. For this purpose, we performed a wssGBLUP (weighted single step genomic best linear unbiased prediction) using data from a ...
Sigurðardóttir H, Ablondi M, Kristjansson T, Lindgren G, Eriksson S.The Icelandic horse and Exmoor pony are ancient, native breeds, adapted to harsh environmental conditions and they have both undergone severe historic bottlenecks. However, in modern days, the selection pressures on these breeds differ substantially. The aim of this study was to assess genetic diversity in both breeds through expected (HE) and observed heterozygosity (HO) and effective population size (Ne). Furthermore, we aimed to identify runs of homozygosity (ROH) to estimate and compare genomic inbreeding and signatures of selection in the breeds. Results: HO was estimated at 0.34 and 0.33...
Woodrow JS, Palmisano M, Kulp J, Hopster K.Complications from general anesthesia, including pneumonia and decreased wound healing, are influenced by changes in immune cell function secondary to sedatives and anesthetics. It was hypothesized that immune cell function would be depressed in the early postanesthetic period. The objective was to investigate airway immune cell function before and after a general anesthetic episode in an equine in vivo model using ex vivo cell stimulations with lipopolysaccharide (LPS) for assessment of immune function. Methods: Prospective experimental study. Methods: Six healthy, adult, institution-owned ...
Leng J, Moller-Levet C, Mansergh RI, O'Flaherty R, Cooke R, Sells P, Pinkham C, Pynn O, Smith C, Wise Z, Ellis R, Couto Alves A, La Ragione R....Gut bacterial communities have a profound influence on the health of humans and animals. Early-life gut microbial community structure influences the development of immunological competence and susceptibility to disease. For the Thoroughbred racehorse, the significance of early-life microbial colonisation events on subsequent health and athletic performance is unknown. Here we present data from a three-year cohort study of horses bred for racing designed to explore interactions between early-life gut bacterial community structure, health events in later life and athletic performance on the race...
Yaneselli K, Ávila G, Rossi A, Rial A, Castro S, Estradé MJ, Suárez G, Algorta A.Platelet lysate (PL) is investigated as a potential replacement for fetal bovine serum (FBS) in cell culture. However, there is limited research on its impact on the immune profile of equine mesenchymal stromal cells (eMSCs). This study aimed to evaluate the effects of different PL formulations on the proliferative capacity, multipotentiality, and immune profile of equine adipose tissue-derived MSCs (eAD-MSCs). growth kinetics and trilineage differentiation of eAD-MSCs ( = 7) were assessed under three culture conditions: medium-concentration PL (MPL), high-concentration PL (HPL), and FBS ...
Bourebaba L, Bourebaba N, Galuppo L, Marycz K.Nowadays, regenerative medicine techniques are usually based on the application of mesenchymal stem cells (MSCs) for the repair or restoration of injured damaged tissues. However, the effectiveness of autologous therapy is limited as therapeutic potential of MSCs declines due to patient's age, health condition and prolonged in vitro cultivation as a result of decreased growth rate. For that reason, there is an urgent need to develop strategies enabling the in vitro rejuvenation of MSCs prior transplantation in order to enhance their in vivo therapeutic efficiency. In presented study, we attemp...
Ringo RS, Choonnasard A, Okabayashi T, Saito A. can establish persistent infections in animals such as equids, pigs, nonhuman primates, rodents, and possums. Some can even cause overt and severe diseases such as Equine Arteritis in horses and Porcine Reproductive and Respiratory Syndrome in pigs, leading to huge economic losses. have evolved viral proteins to antagonize the host cell's innate immune responses by inhibiting type I interferon (IFN) signaling, assisting viral evasion and persistent infection. So far, the role of the glycoprotein 5 (GP5) protein in IFN signaling inhibition remains unclear. Here, we investigated the inhibito...
Jebbawi F, Chemnitzer A, Dietrich M, Pantelyushin S, Lam J, Rhiner T, Keller G, Waldern N, Canonica F, Fettelschoss-Gabriel A.Insect bite hypersensitivity (IBH) is the most frequent skin allergy of horses and is highly debilitating, especially in the chronic phase. IBH is caused by IgE-mediated hypersensitivity reactions to culicoides midge bites and an imbalanced immune response that reduces the welfare of affected horses. Unassigned: In the present study, we investigated the pathological mechanisms of IBH, aiming to understand the immune cell modulation in acute allergic skin lesions of IBH horses with the goal of finding possible biomarkers for a diagnostic approach to monitor treatment success. Unassigned: By qPC...
Da Silva E, Martín-Cano FE, Gómez-Arrones V, Gaitskell-Phillips G, Alonso JM, Rey J, Becerro L, Gil MC, Peña FJ, Ortega-Ferrusola C.Equine endometritis is one of the main causes of subfertility in the mare. Unraveling the molecular mechanisms involved in this condition and pinpointing proteins with biomarker potential could be crucial in both diagnosing and treating this condition. This study aimed to identify the endometritis-induced changes in the endometrial proteome in mares and to elucidate potential biological processes in which these proteins may be involved. Secondly, biomarkers related to bacterial endometritis (BE) in mares were identified. Uterine lavage fluid samples were collected from 28 mares (14 healthy: ne...
Marsella R.Allergy to insects is the most common skin allergy in horses. Pruritus in affected patients can be extreme. Face, ears, mane, and tail area are commonly affected areas. Diagnosis of insect bite hypersensitivity (IBH) is clinical and is based on history, clinical signs, and response to repellents. Allergy tests are not to be used for diagnostic purposes. Currently, there is no specific treatment for IBH other than insect avoidance, treatment of secondary infections, and symptomatic relief of pruritus. Many allergic horses become also sensitized to pollens. For these patients, allergen specific ...
Hart KA, Kimura S.Immunomodulators can stimulate, suppress, or regulate one or many aspects of the immune response. Use of a variety of immunostimulants, immunosuppressors, and anti-inflammatory drugs are described in horses, but the evidence supporting their efficacy is variable. Corticosteroids and nonsteroidal anti-inflammatory drugs are the best characterized immunomodulators in horses, but further study is needed to fully define their ideal dosing protocols and indications and to characterize the efficacy of other immunomodulators in equine medicine.
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...
Wagner B, Babasyan S, Wilford S, Robbin MG, de Mestre AM.CD25, the interleukin-2 receptor α-chain, is expressed on cell surfaces of different immune cells and is commonly used for phenotyping of regulatory T cells (Tregs). CD25 has essential roles in the maintenance of hemostasis and immune tolerance and Treg cell involvement has been shown in human diseases and murine models for allergy, autoimmunity, cancer, chronic inflammation, and many others. In horses, a cross-reactive anti-human CD25 antibody has previously been used for characterizing Tregs. Here, we developed monoclonal antibodies (mAbs) to equine CD25 and compared their staining pattern ...
Marsella R.Autoimmune dermatopathies are not common in horses. These autoimmune diseases can be idiopathic or triggered by an antigen such as drugs, vaccines, or neoplasia. The most common one is pemphigus foliaceus, which manifests as a pustular, crusting eruption. Other more common pustular diseases should be ruled out before considering pemphigus. Vasculitis is relatively common in horses and can be triggered by a variety of antigenic stimulations. Systemic lupus and true idiopathic autoimmune vasculitis are very rare in horses. Every effort should be made to reach a final diagnosis, as the prognosis ...
Knickelbein KE, Lassaline ME.Immune-mediated ocular inflammation is a common clinical diagnosis reached for horses with keratitis and uveitis. This diagnosis is made as a diagnosis of exclusion following a thorough effort to rule out an underlying cause for the inflammation, most importantly infectious and neoplastic disease. Practically, response to ophthalmic and systemic anti-inflammatory or immunomodulatory medications is used to support a diagnosis of immune-mediated ocular inflammation; however, such medications are often contraindicated in the face of infection or neoplasia. This article will summarize our current ...
Bozorgmanesh R.Immune-mediated vasculopathies occur secondary to infection or another noninfectious stimulus. Potential triggers include heterologous antigens including viruses, injected proteins and drugs; or auto-antigens including immunoglobulins or other endogenous proteins. Although these conditions are rare in horses, immune-mediated vasculopathies can cause considerable morbidity, with variable clinical signs depending on severity and organ system affected. Examples include purpura hemorrhagica, systemic lupus erythematosus, drug-induced vasculitis, paraneoplastic vasculitis, and idiopathic immune-med...
Wagner B.Host immune analyses require specific reagents to identify cellular and soluble components of the immune system. These immune reagents are often species-specific. For horses, various immunological tools have been developed and tested by different initiatives during the past decades. This article summarizes the development of well characterized monoclonal antibodies (mAbs) for equine immune cells, immunoglobulin isotypes, cytokines, and chemokines.
Chen L, Li S, Li W, Yu Y, Sun Q, Chen W, Zhou H, Wang C, Li L, Xu M, Khan MZ, Li Y, Wang T.The Nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway has been extensively studied for its role in regulating antioxidant and antiviral responses. The Equid herpesvirus type 8 (EqHV-8) poses a significant threat to the equine industry, primarily manifesting as respiratory disease, abortions, and neurological disorders in horses and donkeys. Oxidative stress is considered a key factor associated with pathogenesis of EqHV-8 infection. Unfortunately, there is currently a dearth of therapeutic interventions available for the effective control of EqHV-8. R...
Rodríguez M, Quiroga J, Cortés B, Morán G, Henríquez C.Tamoxifen (TAM) is widely utilized in the prevention and treatment of human breast cancer and has demonstrated the potential to modulate the immune response. It has been proposed as a therapeutic tool for immune-mediated diseases. TAM has been investigated as a possible treatment for asthma-like conditions in horses, revealing specific impacts on the innate immune system. While the effects of TAM on equine neutrophils are well-documented, its influence on lymphocytes and the modulation of the immune response polarization remains unclear. This study employed peripheral blood mononuclear cells ...
Woodward EM, Christoffersen M, Campos J, Betancourt A, Horohov D, Scoggin KE, Squires EL, Troedsson MH.Transient endometritis after breeding is necessary for clearance of bacteria and spermatozoa; however, in a subpopulation of mares, the inflammation fails to resolve in a timely fashion. The objective of this study was to describe the uterine inflammatory response in mares susceptible or resistant to persistent breeding-induced endometritis (PBIE) during the first 24 h after induction of uterine inflammation.Twelve mares were classified as susceptible (nZ6) or resistant (nZ6) to PBIE. Mares were inseminated over five estrous cycles and endometrial biopsies were collected at one time point per ...
Balasuriya UB, MacLachlan NJ.The members of the family Arteriviridae, genus Arterivirus, include equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), lactate dehydrogenase-elevating virus (LDV) of mice, and simian hemorrhagic fever virus (SHFV). PRRSV is the newest member of the family (first isolated in North America and Europe in the early 1990s), whereas the other three viruses were recognized earlier (EAV in 1953, LDV in 1960, and SHFV in 1964). Although arterivirus infections are strictly species-specific, the causative agents share many biological and molecular properties, inclu...
Richt JA, Pfeuffer I, Christ M, Frese K, Bechter K, Herzog S.The geographic distribution and host range of Borna disease (BD), a fatal neurologic disease of horses and sheep, are larger than previously thought. The etiologic agent, Borna disease virus (BDV), has been identified as an enveloped nonsegmented negative-strand RNA virus with unique properties of replication. Data indicate a high degree of genetic stability of BDV in its natural host, the horse. Studies in the Lewis rat have shown that BDV replication does not directly influence vital functions; rather, the disease is caused by a virus-induced T-cell mediated immune reaction. Because antibodi...
Hernández-Avalos I, Mota-Rojas D, Mendoza-Flores JE, Casas-Alvarado A, Flores-Padilla K, Miranda-Cortes AE, Torres-Bernal F, Gómez-Prado J....Pain and anxiety are two of the most important concerns in clinical veterinary medicine because they arise as consequences of multiple factors that can severely affect animal welfare. The aim of the present review was to provide a description and interpretation of the physiological and behavioral alterations associated with pain and anxiety in equines. To this end, we conducted an extensive review of diverse sources on the topic. The article begins by describing the neurophysiological pathway of pain, followed by a discussion of the importance of the limbic system in responses to pain and anxi...
Pfaender S, Walter S, Grabski E, Todt D, Bruening J, Romero-Brey I, Gather T, Brown RJ, Hahn K, Puff C, Pfankuche VM, Hansmann F, Postel A, Becher P....Hepatitis C virus (HCV) displays a restricted host species tropism and only humans and chimpanzees are susceptible to infection. A robust immunocompetent animal model is still lacking, hampering mechanistic analysis of virus pathogenesis, immune control, and prophylactic vaccine development. The closest homolog of HCV is the equine nonprimate hepacivirus (NPHV), which shares similar features with HCV and thus represents an animal model to study hepacivirus infections in their natural hosts. We aimed to dissect equine immune responses after experimental NPHV infection and conducted challenge ex...
Berglund AK, Fisher MB, Cameron KA, Poole EJ, Schnabel LV.Allogeneic mesenchymal stem cells (MSCs) are a promising cell source for treating musculoskeletal injuries in horses. Effective and safe allogeneic therapy may be hindered, however, by recipient immune recognition and rejection of major histocompatibility complex (MHC)-mismatched MSCs. Development of strategies to prevent immune rejection of MHC-mismatched MSCs in vivo is necessary to enhance cell survival and potentially increase the efficacy and safety of allogeneic MSC therapy. The purposes of this study were to evaluate if transforming growth factor-β2 (TGF-β2) downregulated MHC expressi...
Ahlers LRH, Goodman AG.Vector-borne diseases, including arboviruses, pose a serious threat to public health worldwide. Arboviruses of the flavivirus genus, such as Zika virus (ZIKV), dengue virus, yellow fever virus (YFV), and West Nile virus (WNV), are transmitted to humans from insect vectors and can cause serious disease. In 2017, over 2,000 reported cases of WNV virus infection occurred in the United States, with two-thirds of cases classified as neuroinvasive. WNV transmission cycles through two different animal populations: birds and mosquitoes. Mammals, particularly humans and horses, can become infected thro...
Oladunni FS, Oseni SO, Martinez-Sobrido L, Chambers TM.Equine influenza virus (EIV) is a constantly evolving viral pathogen that is responsible for yearly outbreaks of respiratory disease in horses termed equine influenza (EI). There is currently no evidence of circulation of the original H7N7 strain of EIV worldwide; however, the EIV H3N8 strain, which was first isolated in the early 1960s, remains a major threat to most of the world's horse populations. It can also infect dogs. The ability of EIV to constantly accumulate mutations in its antibody-binding sites enables it to evade host protective immunity, making it a successful viral pathogen. C...
Peroni JF, Borjesson DL.The recent interest in equine stem cell biology and the rapid increase in experimental data highlight the growing attention that this topic has been receiving over the past few years. Within the field of stem cell biology, the relevance of immunobiology is of particular intrigue. It appears that optimal and effective stem cell therapy for equine patients will require a thorough analysis of the immune properties of stem cells as well as their response to immune mediators. The main goal of this review is to discuss the biology of adult mesenchymal stem cells in the context of immunology.
Scanlen M, Paweska JT, Verschoor JA, van Dijk AA.We previously demonstrated that soluble baculovirus-expressed African horsesickness virus (AHSV) serotype 5 VP2 protein (AHSV5 rVP2) elicits neutralising antibodies in guinea pigs. We have now determined the immunogenicity of soluble AHSV5 rVP2 in horses when administered in three different adjuvant types, ISA-50, aluminium phosphate and different saponin preparations. Doses of 10 and 50microg of rVP2 administered with saponin induced full protection to a lethal challenge, albeit with dose-related side effects. The results establish that soluble rVP2 is the biologically active form and that it...
Clark KC, Kol A, Shahbenderian S, Granick JL, Walker NJ, Borjesson DL.Mesenchymal stem cell (MSC) therapy is being increasingly used to treat dogs and horses with naturally-occurring diseases. However these animals also serve as critical large animal models for ongoing translation of cell therapy products to the human market. MSC manufacture for clinical use mandates improvement in cell culture systems to meet demands for higher MSC numbers and removal of xeno-proteins (i.e. fetal bovine serum, FBS). While serum-free media (SFM) is commercially available, its affects on MSC phenotype and immunomodulatory functions are not fully known. The objective of this study...
Minke JM, Audonnet JC, Fischer L.The increasing international movement of horses combined with the relaxation of veterinary regulations has resulted in an increased incidence of equine infectious diseases. Vaccination, along with management measures, has become the primary method for the effective control of these diseases. Traditionally modified live and inactivated vaccines have been used and these vaccines have proven to be very successful in preventing disease. However, there are a number of equine infectious diseases for which conventional technology has shown its limitations. The advent of recombinant technology has sti...
Gryspeerdt AC, Vandekerckhove AP, Garré B, Barbé F, Van de Walle GR, Nauwynck HJ.Equine herpesvirus 1 (EHV1) replicates in the respiratory tract of horses, after which infected leukocytes transport virus throughout the body, resulting in abortion or nervous system disorders. Two EHV1 strains circulate in the field: neurovirulent and non-neurovirulent. To investigate differences in replication in the upper respiratory tract (URT), an experimental inoculation study in ponies was performed with both strains. Two groups of six ponies, were inoculated intranasally with 10(6.5) TCID(50) of either strain. Clinical signs, nasal shedding and viremia were evaluated. At early time po...
Toribio RE, Kohn CW, Capen CC, Rosol TJ.Parathyroid hormone (PTH) is secreted by the chief cells of the parathyroid gland in response to changes in ionized calcium (Ca(2+)) concentrations. In this study, we measured PTH secretion, and PTH mRNA and calcium-sensing receptor (CaR) mRNA expression by equine parathyroid chief cells in vitro. We also evaluated the effects of interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha on PTH secretion, and PTH and CaR mRNA expression. The relationship between PTH and Ca(2+) was inversely related. PTH secretion decreased from 100% (day 0) to 13% (day 30). PTH mRNA expression decline...
MacDonald ES, Barrett JG.One hallmark of mesenchymal stem cells (MSCs) is the ability to differentiate into multiple tissue types which assists in tissue regeneration. Another hallmark of MSCs is their potent anti-inflammatory and immunomodulatory properties and the potential to treat inflammatory, immune-mediated, and ischemic conditions. In equine practice, MSCs have shown efficacy in the treatment of musculoskeletal disorders such as tendinopathy, meniscal tears and cartilage injury. However, there are many equine disease processes and conditions that may benefit from the immunomodulatory properties of MSCs. Exampl...
Paterson YZ, Rash N, Garvican ER, Paillot R, Guest DJ.Autologous mesenchymal stem cells (MSCs) are an attractive concept in regenerative medicine, but their mechanism of action remains poorly defined. No immune response is reported after in vivo injection of allogeneic equine MSCs or embryo-derived stem cells (ESCs) into the equine tendon, which may be due to the cells' immune-privileged properties. This study further investigates these properties to determine their potential for clinical application in other tissues. Methods: Mitomycin C-treated MSCs, ESCs, or differentiated ESCs (dESCs) were cultured with allogeneic equine peripheral blood mono...
Sánchez MD, Pierson TC, Degrace MM, Mattei LM, Hanna SL, Del Piero F, Doms RW.A major neutralizing epitope (here referred to as the T332 epitope) located on the lateral surface of domain III (DIII) of the West Nile virus (WNV) envelope protein has been identified based on the analysis of murine monoclonal antibodies. However, little is known about the humoral immune response against WNV in a natural host or whether DIII in general or the T332 epitope in particular are important targets of neutralizing antibodies in vivo. To characterize the types of antibodies produced during infection with WNV, we studied a group of naturally infected horses. Using immune adsorption as...
Bruhn O, Grötzinger J, Cascorbi I, Jung S.Antimicrobial peptides play a pivotal role as key effectors of the innate immune system in plants and animals and act as endogenous antibiotics. The molecules exhibit an antimicrobial activity against bacteria, viruses, and eukaryotic pathogens with different specificities and potencies depending on the structure and amino-acid composition of the peptides. Several antimicrobial peptides were comprehensively investigated in the last three decades and some molecules with remarkable antimicrobial properties have reached the third phase of clinical studies. Next to the peptides themselves, numerou...
Horohov DW.The modern horse, Equus caballus has historically made important contributions to the field of immunology, dating back to Emil von Behring's description of curative antibodies in equine serum over a century ago. While the horse continues to play an important role in human serotherapy, the mouse has replaced the horse as the predominant experimental animal in immunology research. Nevertheless, continuing efforts have led to an improved understanding of the equine immune response in a variety of infectious and non-infectious diseases. Based on this information, we can begin to identify specific ...
Taylor S.Sepsis is defined as an exaggerated, systemic inflammatory response to infection and is a common condition in horses. Systemic inflammatory response syndrome (SIRS) associated with bacterial infection is a hallmark of sepsis. Sepsis in neonatal foals is a common sequela of failure of passive transfer and, in addition to development of SIRS, may be characterised by bacteraemia, pneumonia, enterocolitis, omphalophlebitis, meningoencephalitis or arthritis. Sepsis in mature horses is most commonly observed secondary to gastrointestinal lesions that result in disrupted mucosa and bacterial transloc...
Contreras-Aguilar MD, Tvarijonaviciute A, Monkeviciene I, Martín-Cuervo M, González-Arostegui LG, Franco-Martínez L, Cerón JJ, Tecles F....Measurement of adenosine deaminase (ADA) can provide information about cell-mediated immunity. This report's objective was to study the enzymatic activity of total ADA (tADA) and its isoenzymes ADA1 and ADA2 in canine, equine, porcine, and bovine serum and saliva and their changes in different inflammatory situations in each species. Besides, an automated method for ADA2 measurement was developed and validated. Results: tADA was present in serum and saliva of healthy animals of the four species. Erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA) concentration of 0.47 mM was needed for ADA1 inhibit...
Summerfield A, Auray G, Ricklin M.Dendritic cells (DC) have a main function in innate immunity in that they sense infections and environmental antigens at the skin and mucosal surfaces and thereby critically influence decisions about immune activation or tolerance. As professional antigen-presenting cells, they are essential for induction of adaptive immune responses. Consequently, knowledge on this cell type is required to understand the immune systems of veterinary mammals, including cattle, sheep, pigs, dogs, cats, and horses. Recent ontogenic studies define bona fide DC as an independent lineage of hematopoietic cells orig...
Jensen-Jarolim E, Pacios LF, Bianchini R, Hofstetter G, Roth-Walter F.Owners and their domestic animals via skin shedding and secretions, mutually exchange microbiomes, potential pathogens and innate immune molecules. Among the latter especially lipocalins are multifaceted: they may have an immunomodulatory function and, furthermore, they represent one of the most important animal allergen families. The amino acid identities, as well as their structures by superposition modeling were compared among human lipocalins, hLCN1 and hLCN2, and most important animal lipocalin allergens, such as Can f 1, Can f 2 and Can f 4 from dog, Fel d 4 from cats, Bos d 5 from cow's...
Lange-Consiglio A, Lazzari B, Perrini C, Pizzi F, Stella A, Cremonesi F, Capra E.Cell-derived microvesicles (MVs) are a recently discovered mechanism of cell-to-cell communication. Our previous data show that MVs secreted by equine amniotic mesenchymal-derived cells (AMCs) are involved in downregulation of proinflammatory genes in lipopolysaccharide-stressed equine tendon and endometrial cells. The aim of the present study was to evaluate whether AMC-MVs contain selected microRNAs (miRNAs) involved in inflammation. Two pools of cells, derived from 3 amniotic membranes each, and their respective MVs were collected. Small RNAs were extracted and deep sequenced, followed by m...
Neuder LE, Keener JM, Eckert RE, Trujillo JC, Jones SL.Endotoxemia occurs when bacterial lipopolysaccharide (LPS) in the blood induces a dysregulated inflammatory response, resulting in circulatory shock and multi-organ failure. Laminitis is a common complication in endotoxemic horses and is frequently the reason for humane euthanasia of these cases. Blood leukocytes are a principal target of LPS in endotoxemia leading to activation of multiple signal transduction pathways involved in the induction of a number of pro-inflammatory genes. In other animal models, the p38 mitogen activated protein kinase (MAPK) pathway has been associated with induced...
Witkowska-Piłaszewicz O, Pingwara R, Winnicka A.Physical activity has an influence on a variety of processes in an athlete's organism including the immune system. Unfortunately, there is a lack of studies regarding racehorse immune cells, especially when the horse model is compared to human exercise physiology. The aim of the study was to determine changes in immune cell proliferation, lymphocyte populations, and monocyte functionality in trained and untrained racehorses after exercise. In this study, field data were collected. The cells from 28 racehorses (14 untrained and 14 well-trained) were collected before and after exercise (800 m at...
Martens RJ, Martens JG, Fiske RA, Hietala SK.The immunoprophylactic capacity of specific immune plasma was evaluated in pony foals infected experimentally with Rhodococcus equi. Immune plasma, produced by repeated parenteral administration of viable R. equi to adult horses, was harvested and frozen. Group I (six control foals) and Group II (six principal foals) received lactated Ringers solution and immune plasma respectively at three and five days of age. R. equi were aerosolised into a caudal lung lobe of all foals at seven days of age. Clinical signs, haematological alterations, immune responses, thoracic radiographs and technetium99m...
Barrachina L, Cequier A, Romero A, Vitoria A, Zaragoza P, Vázquez FJ, Rodellar C.Antibody production after allogeneic administration of mesenchymal stem cells (MSCs) could impact their clinical application. Proinflammatory priming of MSCs can potentiate their regulatory ability in vivo but increased expression of major histocompatibility complex (MHC) might augment their immunogenicity, potentially leading to immune memory thus limiting repeated allogeneic administration. This study aimed at evaluating the production of cytotoxic allo-antibodies directed against donor's ELA (equine leukocyte antigen) in mismatched and halfmatched horses receiving repeated intraarticular ad...
Noronha LE, Antczak DF.The horse has proven to be a distinctively informative species in the study of pregnancy immunology for several reasons. First, unique aspects of the anatomy and physiology of the equine conceptus facilitate approaches that are not possible in other model organisms, such as non-surgical recovery of early stage embryos and conceptuses and isolation of pure trophoblast cell populations. Second, pregnant mares make strong cytotoxic antibody responses to paternal major histocompatibility complex class I antigens expressed by the chorionic girdle cells, permitting detailed evaluation of the antigen...
