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.
Treffers HP, Heidelberger M, Freund J.1. Two horses were injected subcutaneously with alum-precipitated rabbit serum albumin. 2. The resulting antibody resembled diphtheria antitoxin and anti-egg albumin in the horse in giving a sharp zone of flocculation with antigen, in being water-soluble, in reactivity toward an anti-antibody rabbit serum, and in its electrophoretic properties. 3. The effect of continued immunization, and of variation in volume and temperature on the reactivity of the antibody are discussed. 4. Intravenous injection of the same antigen into horses did not give rise to detectable amounts of antibody of the same...
Todd EW.Antiproteinase sera were prepared by immunizing horses with filtrates from a selected strain of group A streptococcus. This strain, which produced high titred proteinase but no erythrogenic toxin, was selected from forty-two strains of group A streptococci which produced varying amounts of proteinase. A few strains belonging to groups B, C, and G were also tested; they were all proteinase-negative. Methods are described for titrating streptococcal proteinase in crude culture filtrates and for measuring the antiproteinase activity of serum. The antiproteinase titres of sera from immunized horse...
Botía M, Muñoz-Prieto A, Martínez-Subiela S, Martín-Cuervo M, Hansen S, Manteca X, Cerón JJ, López-Arjona M.Equine gastric ulcer syndrome (EGUS) is a frequent disease in horses that comprises two different entities: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). This disease considerably reduces the quality of life of affected horses and can negatively affect performance. Saliva contains biomarkers, such as oxytocin, that have been used as a welfare indicator and can develop a function as a protective factor against stress-induced changes in gastric function due to its gastric antisecretory and antiulcer effects. The objective of this work was to evaluate changes...
Yu H, Raymonda JW, McMahon TM, Campagnari AA.This article reviews the recent development of two solid-phase chemiluminescence-based techniques, fluorogenic-chemiluminescence (FCL) and electro-chemiluminescence (ECL) for detection of biological threat agents. Both techniques entail a labeled sandwich immunoassay. The objectives of this work are to develop advanced techniques for sensitive and effective detection of a target analyte, particularly in cases where the analysis includes complex samples containing multiple contaminating factors. Other important considerations in developing such detection techniques include the ease of use, the ...
Sheahan BJ, Schubert AG, Schubert W, Sheats MK, Schnabel LV, Gilbertie JM.Neutrophil extracellular traps (NETs) play a significant role in response to a variety of infectious and inflammatory stimuli in human and veterinary medicine. Although entrapment of bacteria can be an important function of NETs, the exuberant release of DNA and other intracellular molecules has also been negatively implicated in the pathogenesis of different diseases. Thus, NET formation must be tightly controlled and represents an opportunity for therapeutic interventions. Horses are particularly sensitive to bacterial stimuli that have previously been shown to cause NETs in other species, b...
Sun Y, Yu YT, Castillo XO, Anderson R, Wang M, Sun Q, Tallmadge R, Sams K, Reboul G, Zehr J, Brown J, Wang X, Marra N, Stanhope B, Grenier J....Fever of unknown origin (FUO) without a respiratory component is a frequent clinical presentation in horses. Multiple pathogens, both tick-borne and enteric, can be involved as etiologic agents. An additional potential mechanism is intestinal barrier dysfunction. This case-control study aimed to detect and associate microbial taxa in blood with disease state. Areas known for a high prevalence of tick-borne diseases in humans were chosen to survey horses with FUO, which was defined as fever of 101.5°F or higher with no signs of respiratory illness or other recognisable diseases. Blood samples ...
Talib MT, Nasir A, Kashif M, Rahman A, Rehman AU, Akbar H, Nadeem A, Howe DK, Azam MN.The aim of this study was to determine the prevalence of anti-Neospora (N.) caninum and anti-N. hughesi antibodies in horses and to appraise the associated risk factors in the two central districts (Jhang and Toba Tek Singh) of Punjab Province, Pakistan. A total of 300 horse sera were analyzed for the presence of antibodies to Neospora spp. using a competitive ELISA. The overall prevalence of antibodies against Neospora species in horses was 25 % (75/300; 95 % CI 20.1-29.9). The prevalence of antibodies to N. caninum and N. hughesi species was 12.3 % (37/300; 95 % CI 8.6-16) and 19.3 % (5...
Long S, Maleas G, Belacic ZA, Quam VG, Durgam S.To analyze the cellular, growth factor, and cytokine composition of equine sternal bone marrow aspirate (BMA) and laboratory-centrifuged BMA concentrate (BMAC). Unassigned: This was an in vitro experimental study. Cellular composition, growth factors (IGF-I, VEGF, PDGF, TGF-β1), and cytokines (IL-6, IL-10, tumor necrosis factor-α (TNF-α), and IL-1 receptor antagonist protein [IL-1Ra]) were quantified using a standard automated hematology analyzer and ELISA methods, respectively, in donor-matched BMA, BMAC (in-house centrifugation protocol), whole blood, and platelet-rich plasma (E-PET; Pall...
Cheung HW, Wong KS, Choi YC, Kwok WH, So YM, Farrington AF, Bond AJ, Wan TSM, Ho ENM.An increasing number of novel Fc-fusion proteins and monoclonal antibodies (mAbs) are being developed as therapeutic agents for treating various diseases. Among these, there are inhibitors of the activin Type II receptor (ActRIIA and ActRIIB) signaling pathways and mAbs against nerve growth factor (NGF), which may be misused for performance enhancement in horseracing and equestrian sports. This study is aimed at developing a generic detection method for doping control analysis of nine targeted proteins, each containing the Fc domain of human IgG or IgG from other species in equine plasma, name...
Qiu Y, Jiang J, Yi X, Wang S, Sun X.This study investigated the immunoglobulins (IG) gene locus structure and expression diversity in local Chinese horse and donkey breeds, including Ningqiang, Guanzhong horses, and varieties such as Guanzhong, Jiami, and Northern Shaanxi donkey using genome alignment and high-throughput sequencing. The aim was to expand understanding of IG expression patterns in horses, donkeys, and their different breeds. The results revealed that the donkey IGH locus contains 117 VH genes (23 functional), 44 DH genes, and 8 JH genes, arranged in a VH-DH-JH sequence on chromosome 7, spanning approximately 1189...
Di Lucrezia A, Scandurra A, Lotito D, Iervolino V, D'Aniello B, Mastellone V, Lombardi P, Pinelli C.In this study, we assessed the interspecific "social buffering effect" of humans on horses, exploring how human presence influences stress responses in horses in an unfamiliar environment using the "isolation paradigm." We examined nine Haflinger horses under two counterbalanced conditions: with a passive human stranger (social condition) or alone (isolation condition). Stress responses were assessed through cortisol measurements, heart rate monitoring, and behavioral observations. While cortisol levels significantly increased in both conditions, with no notable differences before and after th...
Toy S, Black SR, Pastor AR, Whiteside DP.Acute phase proteins (APPs) are commonly used in domestic equine practice, where they rise rapidly in response to inflammation and decrease soon after resolution. This response provides useful information to identify, monitor, and prognosticate a variety of inflammatory conditions. Asian wild horses (Equus ferus przewalskii) are an endangered relative of the domestic horse, and APP reference intervals (RI) and clinical utility in this species are not well documented. This study used serum samples from clinically healthy Asian wild horses under managed care to establish RI for serum amyloid A (...
Nolen-Walston RD, Kulp JC, Stefanovski D, van Eps AW.Hyperinsulinemia is an important and treatable risk factor for laminitis in horses. Objective: Evaluate the Tosoh AIA-360 automated fluorescence enzyme immunoassay for the measurement of serum insulin concentrations in horses, and compare it to five other immunoassays for insulin quantification. Methods: One hundred serum samples from 83 horses were submitted for insulin measurement. Methods: The Tosoh AIA-360 was assessed against a reference assay (radioactive immunoassay; RIA). Using the same samples, TOS-FEIA, ELISA, and three chemiluminescent immunoassays (CLIA) were assessed for correlati...
Prudhomme J, Bardet C, Rakotoarivony I, Garros C, Bouhsira É, Lienard E.Insect bite hypersensitivity in horses ("sweet itch") is a common pruritic, chronic, seasonal, and recurrent dermatitis affecting approximately 10% of horses in France and is a major concern for the horse industry and private owners. This dermatitis results from an allergic reaction to the saliva of specific biting flies (Diptera: Nematocera), primarily from the Culicoides genus. Given the frequent occurrence of this health problem and the limited investigation in France, we conducted a field survey in the vicinity of a riding stable in southwestern France with a reported chronic case of recur...
Al-Khaldi KO, Al-Ruzaiqi KH, Babji AS, Lim SJ, Sadiq MB, Yimer N.Exercise-induced oxidative stress and inflammation adversely affect the health and performance of athletic horses. This study aimed to evaluate the safety of edible bird's nest (EBN) supplementation and its potential anti-inflammatory and immunomodulatory effects in Arabian race stallions during exercise. Key objectives included assessing EBN's impact on hepatic and renal function, hematological profiles, and sialic acid (SA) levels. Unassigned: Two experiments were conducted on 18 Arabian stallions. In Experiment 1, six healthy stallions were divided into control (n = 2) and EBN-supplemented ...
Chen X, Gulbahar K, Ding H, Nie C, Gao X.Horse milk is a highly valuable organic food that is a promising alternative to cow milk, exhibiting plenty of healthy and immune benefits to human. However, identification of proteins associated human wellness and underlying molecular mechanism in horse milk remain unclear. Unassigned: Label-free mass spectrometry-based protein quantification technology was employed to investigate protein composition of animal milk, including cow, goat, camel and horse milk. Prokaryotic expression and disk diffusion assay were applied to acquire and evaluate antimicrobial activity of candidate proteins. RAW2...
McNabb L, McMahon A, Woube EG, Agnihotri K, Colling A, Broder CC, Kucinskaite-Kodze I, Petraityte-Burneikiene R, Bowden TR, Halpin K.Hendra virus (HeV) is a bat-borne zoonotic agent which can cause a severe and highly fatal disease and can be transferred from animals to humans. It has caused over 100 deaths in horses since it was discovered in 1994. Four out of seven infected humans have died. Since the release of the HeV vaccine (Equivac® HeV Hendra Virus Vaccine for Horses, Zoetis Australia Pty Ltd., Rhodes, NSW 2138) in Australia, there has been an urgent requirement for a serological test for differentiating infected from vaccinated animals (DIVA). All first-line diagnostic serological assays at the Australian Centre f...
Lan Y, Li Y, Wang Y.In recent years, the importance of gut microbiota in digestive absorption, metabolism, and immunity has garnered increasing attention. China possess abundant horse breed resources, particularly Guizhou horses, which play vital roles in local agriculture, tourism, and transportation. Despite this, there is a lack of comparative studies on the gut microbiota of native Guizhou horses (GZH) and imported Dutch Warmblood horses (WH). To address this gap, fecal samples were collected from both GZH and WH, and 16S rRNA high-throughput sequencing was utilized to analyze the differences in their gut mic...
Stapley ED, Bertin FR.Pituitary pars intermedia dysfunction is diagnosed using immunoreactive ACTH concentrations. Glass reportedly binds ACTH, but the clinical relevance of using glass blood tubes for measuring equine ACTH concentrations is controversial. This study investigates whether the collection of whole blood into glass EDTA tubes and storage for up to 6 hours changes ACTH concentrations compared to plastic EDTA tubes. Unassigned: This was a cohort study. Whole blood was collected into both glass and plastic EDTA tubes from 9 horses > 12 years of age, including 4 with pituitary pars intermedia dysfunction a...
Heidenberger J, Reihs EI, Strauss J, Frauenlob M, Gültekin S, Gerner I, Tögel S, Ertl P, Windhager R, Jenner F, Rothbauer M.Osteoarthritis (OA) is a prevalent degenerative joint disorder characterized by cartilage degradation, chronic inflammation, and progressive joint dysfunction. Despite rising incidences driven by ageing and increasing obesity, potent treatments remain elusive, exacerbating the socioeconomic burden. OA pathogenesis involves an imbalance in extracellular matrix (ECM) turnover, mediated by inflammatory cytokines and matrix-degrading enzymes, leading to oxidative stress, chondrocyte apoptosis, and ECM degradation. Additionally, synovial inflammation (synovitis) plays a critical role in disease pro...
Labens R, Saba C, Williams J, Hollis A, Ensink J, José-Cunilleras ELV, Jordana-Garcia M, Bergvall K, Ruppin M, Condon F, Spelta C, Elce Y....Intralesional chemotherapeutic administration represents an important treatment option for equine cutaneous neoplasia. Tigilanol-tiglate (TT), a novel molecule extracted from Fontainea picrosperma, an Australian rainforest plant, is registered for intratumoural treatment of canine MCT, leading to rapid oncosis and tumour slough. Evidence from horses is limited but suggests that efficacy may be similar. Objective: To evaluate the response to intratumoural TT treatment in horses with sarcoids (fibroblastic/nodular) and cutaneous melanomas. Methods: Two noncontrolled prospective multicentre clini...
Levasseur A, Paré J, Aubry P, Iwasawa S, Leung D, Arsenault J.Vaccination is the most efficient tool for preventing West Nile virus (WNV) disease in horses. The objectives of this retrospective study were to: i) estimate the provincial and national horse population in Canada; ii) estimate the annual vaccination coverage for WNV in each province; and iii) compare estimates of provincial annual vaccination coverage. Horse population data (2006-2023) and the number of vaccine doses sold in Canada (2016-2020) were obtained by province. Based on these data and expert consultations, the annual number of vaccine doses administered, and provincial horse populati...
Akçay S, Gurkok-Tan T, Ekici S.Intense physical activity in endurance horses triggers complex immune and inflammatory responses, yet the molecular mechanisms underlying these adaptations remain unclear. This study investigated immune-related transcriptomic changes following a 160 km endurance ride, focusing on sex-based differences. Using a bioinformatics approach, differentially expressed genes (DEGs), pathways, microRNAs (miRNAs), and transcription factors (TFs) were analyzed before (T0) and after (T1) the ride. A protein-protein interaction (PPI) analysis was conducted to identify key regulatory genes. Pathway enrichment...
Conley HE, Davis KU, Adler KB, Lavoie JP, Sheats MK.Asthma is a chronic inflammatory airway disease that affects millions of people worldwide. Horses develop asthma spontaneously and serve as a relevant model for multiple phenotypes and endotypes of human asthma. In horses with equine asthma (EA), environmental organic dust triggers increased inflammatory cytokines, excess airway mucus, reversible bronchoconstriction, and airway inflammation. In horses with severe EA (sEA), lower airway inflammation is invariably neutrophilic, making sEA a potential model for severe neutrophilic asthma in humans. Alveolar macrophages (AM) and airway neutrophils...
Battistin L, Moya LFA, Ferreira LVO, Braz AMM, Carvalho M, Golim MA, Amorim RM.Cell-based therapy using mesenchymal stem cells (MSCs) shows promise for treating several diseases due to their anti-inflammatory and immunomodulatory properties. To enhance the therapeutic potential of MSCs, in vitro priming strategies have been explored. Cannabidiol (CBD), a non-psychoactive compound derived from cannabis, may influence MSC proliferation, differentiation, and immunomodulatory properties. This study evaluates the immunomodulatory potential of equine adipose tissue-derived MSCs (EqAT-MSCs) primed with a CBD-rich cannabis extract. EqAT-MSCs (P3) were primed with CBD concentrati...
Li X, Hu S, Yu Z, He F, Zhao X, Liu R.Nanoplastics (NPs) are emerging pollutants worldwide. Particularly worrisome is that although studies have reported that NPs can amplify the biotoxicity of environmental pollutants, the specific mechanism remains unclear. Here, we found that NPs, even without significant toxicity (cell survival: 99.11%), amplified the hepatocyte toxicity of Cd. Mechanistically, higher Cd uptake (Δ = 23.80%) combined with crucial intracellular desorption behavior of Cd loaded in NPs (desorption rate: 82.70%) were identified as prerequisites for NPs amplifying Cd cytotoxicity. As for toxigenic pathways, the inf...
Jung Y, Yoon M.Therapeutic programs involving human-horse interactions are gaining popularity as a means of enhancing human well-being. Understanding the physiological responses of both humans and horses during these interactions is essential for evaluating the effectiveness of such programs. This study examined the effects of specific interactive activities on both humans and horses by monitoring changes in oxytocin and cortisol levels. Six participants and six horses took part in the study. The participants engaged in three distinct activities, each lasting 15 min: (1) resting alone without the horse (rest...
Kamutzki CJ, Emmerich IU.In 2024, there was no release of a novel pharmaceutical agent for horses and food-producing animals or an extension of existing active ingredients to other animal species on the German veterinary medicinal products market. Formic acid is now available for a new form of treatment, the short-term treatment of honeybees, and clenbuterol is available in a new dosage form, as an oral solution for horses. In the field of immunological veterinary medicinal products, three new vaccines were launched on the German veterinary medicinal products market. For the first time, a vaccine against in cattle, a...
da Silva-Álvarez E, Gómez-Arrones V, Correa-Fiz F, Martín-Cano FE, Gaitskell-Phillips G, Carrasco JJ, Rey J, Aparicio IM, Peña FJ, Alonso JM....This study aims to unveil potential differences in the vaginal and uterine microbiomes in mares and jennies, and to identify possible mechanisms involved in uterine immune homeostasis. The microbiota was characterized using 16S rRNA sequencing, and the uterine proteome was analyzed using UHPLC/MS/MS in 18 samples from healthy mares and 14 from jennies. While taxonomic analysis revealed high interspecies similarities, β-diversity analysis showed distinct clustering, with only two vaginal taxa and five uterine taxa differing between species. Despite compositional differences, PICRUSt analysis s...
Liu D, Zhao X, Wang X.Equine herpesvirus 1 (EHV-1), EHV-4, EHV-8, and EHV-9, are classified within the subfamily and are recognized as causative agents of respiratory, urogenital, and neurological disorders in horses. These viruses, collectively referred to as αEHVs, exhibits both unique and shared characteristics in terms of host interaction, pathogenesis, epidemiology, and immune evasion, which arise from both the identities and discrepancies among respective genomic homologs. The genomic architecture of αEHVs is similar to other members of the same subfamily, such as well-known HSV-1, VZV, and PRV. However, r...
The objective of the present study was to investigate the influence of daily rhythms on the immune and inflammatory systems in horses, considering white blood cell count (WBCs), leukocyte subpopulations (neutrophils, basophils, eosinophils, lymphocytes, and monocytes), CD4+, and CD8+ lymphocyte populations, interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Ten Italian Saddle horses (7-12 years old, body weight 480 ± 30 kg) underwent blood sampling every 4 h over a 24-h period. The COSINOR method was used to identify rhythms and their parameters. A one-way ...
Gao X, Liu J, Xu K, Hu J, Xiao C, Wang D, Li C, Ji C, Yao X, Wang PG, Jing Y, He Y, Shen CK.Typically, the antigen-specific antibodies constitute a small fraction-often estimated to be around 2-10 %-of the total IgG in the serum after immunization. This low percentage necessitates the use of purification techniques to enrich the antigen-specific antibodies for therapeutic or research purposes. This study introduces an affinity chromatography column using NHS-activated Sepharose as a matrix and the tetanus toxin subunit C, TeNT-Hc-C869A, as a ligand, enabling the purification of polyclonal antibodies with high specificity. This process improves antitoxin purity to over 95 %, effecti...
