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.
Jakop U, Hensel B, Czirják GÁ, Quirino M, Schröter F, Jung M, Schulze M.During insemination, bacterial contamination of the ejaculate can lead to reduced sperm quality and transmission of pathogens to the female, thus should be avoided. The semen of a variety of animal taxa possess antimicrobial properties against a wide range of bacterial species through antimicrobial molecules, such as lysozyme, but their variance and the factors influencing it are unknown for most species. In this study, the antibacterial defence (bacterial killing activity (BKA) against Escherichia (E.) coli and Staphylococcus (S.) aureus as well as lysozyme concentration) was studied in semin...
Rudolf Vegas A, Hamdi M, Podico G, Bollwein H, Fröhlich T, Canisso IF, Bauersachs S, Almiñana C.In contrast to other domestic mammals, the embryo-derived signal(s) leading to maternal recognition of pregnancy (MRP) are still unknow in the mare. We hypothesize that these embryonic signals could be packed into uterine extracellular vesicles (uEVs), acting as multi-signal messengers between the conceptus and the maternal tract, and contributing to MRP. To unveil these signals, the RNA and protein cargos of uEVs isolated from uterine lavages collected from pregnant mares (P; day 10, 11, 12 and 13 after ovulation) and cyclic control mares (C; day 10 and 13 after ovulation) were analyzed. Our ...
Bao W, Yu J, He Y, Liu M, Yang X.The intestinal flora has a variety of physiological functions involved in the regulation of host metabolism, immunity and endocrinology, and plays an important role in maintaining the health of the host. In this study, we used high-throughput sequencing technology to analyze the intestinal bacterial diversity and their gene functions in three equine species of the genus Shetland Pony (SP), Mongolian Wild Ass (MA), and Plain Zebra (PZ) in captivity in two wildlife parks in Inner Mongolia Autonomous Region, China. The results showed that only the SP intestinal bacterial abundance index (Chao1) w...
Bigler NA, Bruckmaier RM, Gross JJ.Maternal care is essential to optimally support survival of the offspring. During evolution of mammalian species, different phenotypes have evolved in relation to gestation length, number, size, and maturation stage of the offspring at parturition, as well as colostrum and milk composition. The aim of the present review is to describe relationships between placental function and colostrum and milk composition in different mammalian species. Species covered in this article include humans, rabbits, rodents (rat and mouse), carnivores (cats and dogs), and a variety of ungulate species (cattle, sh...
Even KM, Gaesser AM, Ciamillo SA, Linardi RL, Ortved KF.Joint injury often leads to cartilage damage and posttraumatic inflammation, which drives continued extracellular matrix degradation culminating in osteoarthritis. Mesenchymal stem cells (MSCs) have been proposed as a biotherapeutic to modulate inflammation within the joint. However, concerns have been raised regarding the immunogenicity of MSCs cultured in traditional fetal bovine serum (FBS) containing media, and the potential of xenogenic antigens to activate the immune system causing rejection and destruction of the MSCs. Xenogen-free alternatives to FBS have been proposed to decrease MSC ...
Schmucker S, Preisler V, Marr I, Krüger K, Stefanski V.Domestic horses are currently often subject to management practices that can entail social stressors, which in turn can negatively influence immunocompetence and disease susceptibility. The present study therefore aimed to characterize the number of various blood leukocyte subsets in horses, focusing on two potentially stressful housing environments: changes in group composition and relocation to individual stabling. Immune measurements were conducted before as well as one and eight days after changes were made. They were complemented by an assessment of plasma cortisol concentrations as well ...
Kahn SK, Cohen ND, Bordin AI, Coleman MC, Heird JC, Welsh TH.The bacterium Rhodococcus equi causes pneumonia in foals that is prevalent at breeding farms worldwide. In the absence of an effective vaccine, transfusion of commercial plasma from donor horses hyperimmunised against R. equi is used by many farms to reduce the incidence of pneumonia among foals at farms where the disease is endemic. The effectiveness of hyperimmune plasma for controlling R. equi pneumonia in foals has varied considerably among reports. The purposes of this narrative review are: (1) to review early studies that provided a foundational basis for the practice of transfusion of h...
Sponseller BT, Wong DM, Ruby R, Ware WA, Wilson S, Haynes JS.A 9-year-old Quarter Horse gelding was presented for lethargy, decreased appetite, polyuria and polydipsia (PU/PD), and severe muscle wasting suggestive of immune-mediated myositis. Results: The horse displayed lethargy, fever, tachyarrhythmia, inappetence, PU/PD, and severe epaxial and gluteal muscle wasting. Clinicopathologic findings were consistent with previously reported cases of systemic calcinosis in horses, including increased muscle enzyme activity, hyperphosphatemia, increased calcium-phosphorus product, hypoproteinemia, and an inflammatory leukogram. A diagnosis of systemic calcino...
Hu D, Tang Y, Wang C, Qi Y, Ente M, Li X, Zhang D, Li K, Chu H.The microbiota and its metabolites play an important role in regulating the host metabolism and immunity. However, the underlying mechanism is still not well studied. Thus, we conducted the LC-MS/MS analysis and RNA-seq analysis on with and without horse botfly infestation to determine the metabolites produced by intestinal microbiota in feces and differentially expressed genes (DEGs) related to the immune response in blood and attempted to link them together. The results showed that parasite infection could change the composition of microbial metabolites. These identified metabolites could b...
Lucassen A, Hankel J, Finkler-Schade C, Osbelt L, Strowig T, Visscher C, Schuberth HJ.Feed supplements such as fermentation products (SCFP) alter immune responses in horses. The purpose of this study was to analyze whether a prebiotic activity of the SCFP alters the gut microbiome in horses. Racehorses were fed either SCFP (Olimond BB, OLI, = 6) or placebo pellets (PLA, = 5) for 43 days. Fecal microbiota analysis was performed using 16S rRNA gene sequencing. The numbers and function of circulating immune cell subpopulations were analyzed by flow cytometry. SCFP supplementation resulted in non-consistent differences in fecal microbiota between the PLA and OLI during the feedi...
da Cunha Neto CAV, Badial PR, de Oliveira-Filho JP, de Andrade DGA, Araujo JP, Borges AS.Hereditary equine regional dermal asthenia (HERDA) is a genetic disease that alters collagen biosynthesis. Affected horses exhibit fragile, hyperextensible skin, especially over the dorsal region. Although ultraviolet (UV) radiation seems to contribute to the regional distribution of lesions and worsening of clinical signs, the molecular mechanisms involved are largely unknown. Objective: To evaluate the effect of solar radiation on matrix metalloproteinase MMP1, MMP8 and MMP13 gene expression in the dorsal and ventral skin of HERDA-affected and HERDA-unaffected horses [wild-type (WT) horses]....
Cantatore F, Marcatili M, Withers J.Stiff-person syndrome is a well-recognised disease in humans, whilst cases of stiff-horse syndrome (SHS) have been rarely reported in the veterinary medicine literature. SHS is a progressive immunomediated disorder of the central nervous system leading to a disturbance of gamma amino butyric acid transmission at the neuromuscular junction in which antibodies are produced against the enzyme glutamic acid decarboxylase. A 6 year-old Irish Sport Horse was presented for investigation of involuntary violent contraction of hindlimb and back muscles triggered by stress. The diagnosis of SHS was made ...
Elferink AJW, Entiriwaa D, Bulgarelli P, Smits NGE, Peters J.Processed milk and milk products produced from bovine milk, commonly contain β-casein A1 (βCA1) and β-casein A2 (βCA2). Since the presence of βCA1 is linked to milk intolerance and digestion problems, A2A2 milk, which only contains βCA2, is proposed as a healthier alternative. To support this health claim, the purity of A2A2-milk has to be guaranteed. In the presented study, a multiplex immunoassay, able to distinguish between βCA2 and βCA1, was developed and real-life applicability was shown on raw milk samples from genotyped A1A1, A1A2 and A2A2 cows. Because of its ability to discrim...
One health outlookMay 9, 2022
Volume 4, Issue 1 9 doi: 10.1186/s42522-022-00065-y
Gömer A, Puff C, Reinecke B, Bracht S, Conze M, Baumgärtner W, Steinmann J, Feige K, Cavalleri JMV, Steinmann E, Todt D.The Equine Hepacivirus (EqHV) is an equine-specific and liver-tropic virus belonging to the diverse genus of Hepaciviruses. It was recently found in a large donkey (Equus asinus) cohort with a similar seroprevalence (30%), but lower rate of RNA-positive animals (0.3%) compared to horses. These rare infection events indicate either a lack of adaptation to the new host or a predominantly acute course of infection. Methods: In order to analyze the susceptibility and the course of EqHV infection in donkeys, we inoculated two adult female donkeys and one control horse intravenously with purified Eq...
Zandoná Meleiro MC, de Carvalho HJC, Ribeiro RR, da Silva MD, Salles Gomes CM, Miglino MA, de Santis Prada IL.Racehorses are constantly exposed to stress. Aiming to verify the state of blood components and cortisol alterations during their routine and after races, phagocytosis and oxidative neutrophil burst assays, serum cortisol determination, erythrocytes apoptosis evaluation, lymphoproliferation assays, and blood count tests were performed in thirty Thoroughbred racehorses, which were divided in two groups. The samples were taken right after races (moment 0 d), during rest periods (-11 d, +1 d, +3 d), and after training (-8, +2, +5). In both groups, the phagocytosis showed a decrease in percentage ...
Birdwhistell KE, Hurley DJ, Heins B, Peroni JF.Allogeneic solid organ transplantation is currently the only treatment option for end stage organ disease. The shortage of available donor organs has driven efforts to utilize xenogeneic organs for transplantation. In vitro methods for evaluating immune-compatibility are a quick and low cost means of screening novel tissue products prior to more involved, expensive, and invasive live animal studies. Recently, a new analog of the DNA base thymidine, 5-ethynyl-2'-deoxyuridine (EdU), was developed. It may be used in a fast, efficient and specific means of evaluating cell proliferation via flow cy...
Muñoz-Prieto A, Contreras-Aguilar MD, Cerón JJ, Ayala I, Martin-Cuervo M, Gonzalez-Sanchez JC, Jacobsen S, Kuleš J, Beletić A, Rubić I, Mrljak V....Changes in the salivary proteome in 12 horses with the two diseases included in equine gastric ulcer syndrome (EGUS), equine glandular gastric disease (EGGD) (n = 6) and equine squamous gastric disease (ESGD) (n = 6), were evaluated using a high-resolution LC-MS/MS analysis of TMT-labelled peptides and compared to 10 healthy control horses. Serum was also analysed for comparative purposes. The comparison between the horses with EGGD and controls showed significant changes in 10 salivary proteins, whereas 36 salivary proteins were differently abundant between ESGD and control groups. The most u...
Li Y, Lan Y, Zhang S, Wang X.Increasing evidence reveals the importance of gut microbiota in animals for regulating intestinal homeostasis, metabolism, and host health. The gut microbial community has been reported to be closely related to many diseases, but information regarding diarrheic influence on gut microbiota in horses remains scarce. This study investigated and compared gut microbial changes in horses during diarrhea. The results showed that the alpha diversity of gut microbiota in diarrheic horses decreased observably, accompanied by obvious shifts in taxonomic compositions. The dominant bacterial phyla (, and )...
Rosa GDS, Krieck AMT, Padula ET, Stievani FC, Rossi MC, Pfeifer JPH, Basso RM, Braz AMM, Golim MA, Alves ALG.Allogeneic mesenchymal stem cells (MSC) are widely used in clinical routine due to the shorter expansion time and reliability of its quality. However, some recipients can produce alloantibodies that recognize MSCs and activate the immune system, resulting in cell death. Although antibody production was already described after MSC injection, no previous studies described the immune response after intra-articular MSC injection in acute synovitis. This study aimed to evaluate the influence of inflammation on immune response after single and repeated intra-articular injections of synovial membrane...
Cequier A, Romero A, Vázquez FJ, Vitoria A, Bernad E, Fuente S, Zaragoza P, Rodellar C, Barrachina L.Immunomodulation and immunogenicity are pivotal aspects for the therapeutic use of mesenchymal stem cells (MSCs). Since the horse is highly valuable as both a patient and translational model, further knowledge on equine MSC immune properties is required. This study analysed how inflammation, chondrogenic differentiation and compatibility for the major histocompatibility complex (MHC) influence the MSC immunomodulatory-immunogenicity balance. Equine MSCs in basal conditions, pro-inflammatory primed (MSC-primed) or chondrogenically differentiated (MSC-chondro) were co-cultured with either autolo...
Alberghina D, Statelli A, Monteverde V, Vazzana I, Cascone G, Panzera M.The values for basal serum cortisol concentrations of horses are available in many studies. However, there are limited data about serum cortisol in donkeys. The present study aimed to determine the baseline values for serum cortisol, to evaluate the influence of age and pregnancy on its levels, and to correlate its values with leucocyte profile, serum cholesterol, and triglycerides. Serum samples were collected from 97 healthy donkeys. Cortisol was analyzed by chemo-luminescent assay. The median and the 2.5th and 97.5th percentiles of serum cortisol measured and calculated in all donkeys were ...
Bordin AI, Huber L, Sanz MG, Cohen ND.Pneumonia in foals caused by the bacterium Rhodococcus equi has a worldwide distribution and is a common cause of disease and death for foals. The purpose of this narrative review was to summarise recent developments pertaining to the epidemiology, immune responses, treatment, and prevention of rhodococcal pneumonia of foals. Screening tests have been used to implement earlier detection and treatment of foals with presumed subclinical R. equi pneumonia to reduce mortality and severity of disease. Unfortunately, this practice has been linked to the emergence of antimicrobial-resistant R. equi i...
Simões J, Batista M, Tilley P.Severe equine asthma is a chronic respiratory disease of adult horses, occurring when genetically susceptible individuals are exposed to environmental aeroallergens. This results in airway inflammation, mucus accumulation and bronchial constriction. Although several studies aimed at evaluating the genetic and immune pathways associated with the disease, the results reported are inconsistent. Furthermore, the complexity and heterogeneity of this disease bears great similarity to what is described for human asthma. Currently available studies identified two chromosome regions (ECA13 and ECA15) a...
Gupta SK.Mammalian zona pellucida (ZP) is composed of three to four glycoproteins, which plays an important role during fertilization. Mutations in the genes encoding zona proteins are reported in women with empty follicle syndrome, degenerated oocytes and those with an abnormal or no ZP further emphasizing their relevance during fertility. Immunization with either native or recombinant ZP glycoproteins/proteins leads to curtailment of fertility in various animal species. Observed infertility is frequently associated with ovarian pathology characterized by follicular atresia and degenerative changes in...
Lee GKC, Kang H, Beeler-Marfisi J, Sears W, Lillie BN, Bienzle D.Salivary scavenger and agglutinin (SALSA) is a secreted protein with various immunomodulatory roles. In humans, the protein agglutinates and inactivates microorganisms, and inhibits the release of pro-inflammatory cytokines. Saliva, which is rich in SALSA, accelerates bacterial phagocytosis, but SALSA's contribution is unclear. In horses, the functions of SALSA in inflammation remain undetermined, so they were investigated through phagocytosis and cytokine assays. Equine SALSA was purified from duodenal tissue, which contains abundant SALSA. To assess phagocytosis, fluorescently-labelled bacte...
Jasiński T, Zdrojkowski Ł, Kautz E, Juszczuk-Kubiak E, Ferreira-Dias G, Domino M.Endometritis is an important issue decreasing mares' fertility. In the case of endometritis, both inflammatory cells infiltration and proinflammatory molecules production are regulated by various cellular and gene regulatory mechanisms, including the nuclear factor-κB (NF-κB)-dependent pathway. NF-κB-signalling pathway has been recently studied in the equine endometrium in the context of endometrosis. Thus, this study aimed to determine gene transcription of NF-κB subunits (RelA; NF-κB1; NF-κB2), proinflammatory molecules (MCP-1; IL-6) and hyaluronan synthases (HAS 1; HAS 2; HAS 3) in en...
Baakhtari M, Imaizumi N, Kida T, Yanagita T, Ramah A, Ahmadi P, Takebe N, Iwamoto Y, Korosue K, Tsuzuki N, Yasuda M.High-intensity exercise and competition are associated with depressed immune function. Young horses, which participate in high-intensity exercise and competitions, are at increased risk for the development of infectious disease due to depression of immune function. The effects of branched-chain amino acid (BCAA) supplementation on the immune status of young racing horses were evaluated, determining whether BCAA might help to avoid or reduce immune suppression during exercise and competitions. Twenty horses (10 male and 10 female) were treated with BCAA supplementation; another twenty untreated...
Theuerkauf K, Obach-Schröck C, Staszyk C, Moritz A, Roscher KA.In humans, activated platelets contribute to sepsis complications and to multiple organ failure. In our prospective analytical study of cases of the equine systemic inflammatory response syndrome (SIRS), we adapted a standard human protocol for the measurement of activated platelets and platelet-leukocyte aggregates (PLAs) in equine platelet-leukocyte-rich plasma (PLRP) by flow cytometry, and we investigated the hypothesis that activated platelets and PLAs are increased in clinical cases of SIRS. We included 17 adult horses and ponies fulfilling at least 2 SIRS criteria, and 10 healthy equids ...
Domańska D, Trela M, Pawliński B, Podeszewski B, Domino M.The somatic cell count in milk (SCC) and electrical conductivity of milk (ECM) are indicators of the health status of the mammary gland. Among somatic cells, mainly polymorphonuclear neutrophils (PMN), macrophages (MAC), and lymphocytes (LYM) are rated. This study aimed to determine the SCC, PMN, MAC, LYM, ECM, and bacteriological index (BII) in milk collected from mares with (CM) and without (NCM) clinical symptoms of mastitis concerning mares with (SM) and without (NSM) subclinical mastitis. Milk samples were collected from 27 mares divided into NCM (n = 12) and CM (n = 15) groups. In sample...
Sheats MK, Pescosolido KC, Hefner EM, Sung EJ, Adler KB, Jones SL.Neutrophil infiltration is a prominent feature in a number of pathologic conditions affecting horses including recurrent airway obstruction, ischemia-reperfusion injury, and laminitis. Cell signaling components involved in neutrophil migration represent targets for novel anti-inflammatory therapies. In order to migrate into tissue, neutrophils must respond to chemoattractant signals in their external environment through activation of adhesion receptors (i.e. integrins) and reorganization of the actin cytoskeleton. Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS), a highly conserved actin...
Menarim BC, Gillis KH, Oliver A, Mason C, Werre SR, Luo X, Byron CR, Kalbfleisch TS, MacLeod JN, Dahlgren LA.Synovial inflammation is a central feature of osteoarthritis (OA), elicited when local regulatory macrophages (M2-like) become overwhelmed, activating an inflammatory response (M1-like). Bone marrow mononuclear cells (BMNC) are a source of naïve macrophages capable of reducing joint inflammation and producing molecules essential for cartilage metabolism. This study investigated the response of BMNC to normal (SF) and inflamed synovial fluid (ISF). Equine BMNC cultured in autologous SF or ISF (n = 8 horses) developed into macrophage-rich cultures with phenotypes similar to cells native to no...
Wagner B, Wimer C, Freer H, Osterrieder N, Erb HN.The recent increase in incidence, morbidity, and mortality of neurological disease induced by equine herpesvirus type 1 (EHV-1) has suggested a change of virulence of the virus. The exact mechanisms by which EHV-1 induces neurologic disease are not known. Environmental, viral, and host risk factors might contribute to neurological manifestation. Here, we investigated innate interferon-α (IFN-α), interleukin-10 (IL-10) and IL-4 responses after infection of equine peripheral blood mononuclear cells (PBMC) with EHV-1 using an available cytokine multiplex assay. Three viral strains representing ...
Staiger EA, Tseng CT, Miller D, Cassano JM, Nasir L, Garrick D, Brooks SA, Antczak DF.The common equine skin tumors known as sarcoids have been causally associated with infection by bovine papillomavirus (BPV). Additionally, there is evidence for host genetic susceptibility to sarcoids. We investigated the genetic basis of susceptibility to sarcoid tumors on a cohort of 82 affected horses and 270 controls genotyped on a genome-wide platform and two custom panels. A Genome Wide Association Study (GWAS) identified candidate regions on six chromosomes. Bayesian probability analysis of the same dataset verified only the regions on equine chromosomes (ECA) 20 and 22. Fine mapping us...
Angulo-Valadez CE, Scholl PJ, Cepeda-Palacios R, Jacquiet P, Dorchies P.Larvae causing obligatory myiasis are numerous and they may affect cutaneous and subcutaneous tissues, wounds, nasopharyngeal cavities (nasal bots), internal organs and the digestive tract (bots) of domestic and wild animals and humans as well. Nasal bots belong to the Family Oestridae, Subfamily Oestrinae, which includes several important genera: Oestrus, Kirkioestrus, and Gedoelstia infecting Artiodactyla (except Cervidae) in Africa and Eurasia, Cephenemyia and Pharyngomyia infecting Cervidae, Rhinoestrus infecting horses, Cephalopina infecting camels, Pharyngobolus infecting African elephan...
Capomaccio S, Cappelli K, Spinsanti G, Mencarelli M, Muscettola M, Felicetti M, Verini Supplizi A, Bonifazi M.Horses and humans share a natural proclivity for athletic performance. In this respect, horses can be considered a reference species in studies designed to optimize physical training and disease prevention. In both species, interleukin-6 (IL-6) plays a major role in regulating the inflammatory process induced during exercise as part of an integrated metabolic regulatory network. The aim of this study was to compare IL-6 and IL-6 receptor (IL-6R) mRNA expression in peripheral blood mononuclear cells (PBMCs) in trained and untrained humans and horses. Results: Nine highly trained male swimmers (...
Massoco C, Palermo-Neto J.Benzodiazepines (BDZ) are among the most frequently used class of psychotropic drugs employed in veterinary medicine in Brazil and worldwide due to their anxiolytic, muscle relaxant and anticonvulsant effects [J. Clin. Pharmacol. 33 (1993) 124]. Peripheral benzodiazepine receptor (PBR) sites were described in peripheral organs, endocrine steroidogenic tissues and immune organs and cells. Midazolam is a mixed-type agonist of PBRs. The present study is focused on the effects of midazolam on equine peripheral blood neutrophils, peritoneal macrophages and cortisol levels in plasma. Adult horses we...
O'Neill T, Kydd JH, Allen GP, Wattrang E, Mumford JA, Hannant D.The frequency of antigen-specific, genetically restricted cytotoxic T lymphocyte precursors (CTLp) was measured in peripheral blood mononuclear cells (PBMC) of ponies before and after infection with equid herpesvirus 1 (EHV1). Split-well limiting dilution analysis (LDA) was developed to measure CTLp frequency using EHV1-infected 51Cr-labelled lymphoblasts as targets. Extensive characterisation showed that recombinant human interleukin-2, autologous antigen presenting cells and equine serum containing virus neutralising antibody were necessary for maturation of CTLp into effector CTL in vitro. ...
Armstrong RA, Lawrence RA, Jones RL, Wilson NH, Collier A.1. This study describes attempts to compare prostacyclin (IP-) receptors in human, pig, horse, rabbit and rat platelets and in circular muscle of human, rabbit and dog mesenteric and pig gastroepiploic arteries. Three stable prostacyclin analogues, iloprost, cicaprost and 6a-carba-prostacyclin (6a-carba-PGI2) and a prostaglandin endoperoxide analogue EP 157 (previously shown to mimic prostacyclin on human platelets) were used. 2. Our main conclusion is that prostacyclin receptors on human, pig and horse platelets are similar in nature, but distinct from those on rabbit and rat platelets. Funct...
Arfuso F, Giudice E, Panzera M, Rizzo M, Fazio F, Piccione G, Giannetto C.The monitoring of endocrine and immunologic markers during exercise is of paramount importance to assess and/or maintain the physical well-being of athletes as well as to optimize the athletic performance. This study aimed to investigate the linkage between acute stress response and immune status in Thoroughbred horses competing in an official 1300-m race. From 10 horses blood was collected 1 week before the day of the race (1W-BEFORE), before (REST) and immediately after the race to assess the cortisol, Interleukin-1 receptor antagonist (IL-1Ra), total proteins, white blood cells (WBC), red b...
Hedrick PW, Parker KM, Miller EL, Miller PS.The major histocompatibility complex (MHC) is a fundamental part of the vertebrate immune system, and the high variability in many MHC genes is thought to play an essential role in recognition of parasites. The Przewalski's horse is extinct in the wild and all the living individuals descend from 13 founders, most of whom were captured around the turn of the century. One of the primary genetic concerns in endangered species is whether they have ample adaptive variation to respond to novel selective factors. In examining 14 Przewalski's horses that are broadly representative of the living animal...
Simões J, Batista M, Tilley P.Severe equine asthma is a chronic respiratory disease of adult horses, occurring when genetically susceptible individuals are exposed to environmental aeroallergens. This results in airway inflammation, mucus accumulation and bronchial constriction. Although several studies aimed at evaluating the genetic and immune pathways associated with the disease, the results reported are inconsistent. Furthermore, the complexity and heterogeneity of this disease bears great similarity to what is described for human asthma. Currently available studies identified two chromosome regions (ECA13 and ECA15) a...
Watson ED.Post-breeding endometritis is a major cause of subfertility in the mare. Endometritis is a normal event in the immediate period after mating, but the presence of ultransonographically visible uterine fluid more than 12 h later is thought to be evidence of uterine pathology. In mares that are free of venerally transmitted endometritis, treatment is aimed at removing the intraluminal fluid. If the endometritis persists past day 5, when the embryo enters the uterine lumen, the cytotoxic environment will not be compatible with pregnancy. Reproductive anatomy, defective myometrial contractility, lo...
Davis AB, Schnabel LV, Gilger BC.Equine immune-mediated keratitis (IMMK) leads to increased corneal opacity and inflammation secondary to an alteration of the local immune system. Bone marrow-derived mesenchymal stem cells (BM-MSC) have been shown to modulate the immune system by downregulating inflammation. Four horses with unilateral IMMK poorly responsive to traditional medical treatments underwent novel, autologous subconjunctival BM-MSC therapy. Bone marrow was harvested and processed as previously described for equine orthopedic disease. Horses received autologous subconjunctival BM-MSC injections approximately every 3-...
Fumuso EA, Aguilar J, Giguère S, Rivulgo M, Wade J, Rogan D.Our objective was to characterize immune parameters in susceptible (SM) and resistant (RM) mares, with and without artificial insemination (AI) and immunomodulation. Eight RM and eight SM were selected based on their reproductive history and functional tests. Both groups of mares were evaluated during three consecutive cycles: Cycle 1, untreated cycle (control); Cycle 2, AI with dead semen; Cycle 3, AI with dead semen and immunomodulation. Endometrial biopsies were taken during the three cycles as follows: Cycle 1--at estrus, when follicles > or =35mm and at diestrus (7+/-1 days after ovula...
Perryman LE.Severe combined immunodeficiency (SCID) is an inherited disorder of humans, mice, horses, and dogs, in which affected individuals are incapable of generating antigen-specific immune responses. It occurs when lymphocyte precursors fail to differentiate into mature lymphocytes because of mutations within recombinase-activating genes 1 and 2 or within the genes encoding deoxyribonucleic acid (DNA)-dependent protein kinase (DNA-PK). It also occurs when differentiated lymphocytes are incapable of completing signal transduction pathways because of defects in cell surface receptors for interleukins (...
Wimer CL, Schnabel CL, Perkins G, Babasyan S, Freer H, Stout AE, Rollins A, Osterrieder N, Goodman LB, Glaser A, Wagner B.The equine herpesvirus type 1 (EHV-1) ORF1 and ORF71 genes have immune modulatory effects in vitro. Experimental infection of horses using virus mutants with multiple deletions including ORF1 and ORF71 showed promise as vaccine candidates against EHV-1. Here, the combined effects of ORF1 and ORF71 deletions from the neuropathogenic EHV-1 strain Ab4 on clinical disease and host immune response were further explored. Three groups of EHV-1 naïve horses were experimentally infected with the ORF1/71 gene deletion mutant (Ab4ΔORF1/71), the parent Ab4 strain, or remained uninfected. In comparison t...
Rapacz-Leonard A, Dąbrowska M, Janowski T.During pregnancy in larger mammals, the maternal immune system must tolerate the fetus for months while resisting external infection. This tolerance is facilitated by immunological communication between the fetus and the mother, which is mediated by Major Histocompatibility Complex I (MHC I) proteins, by leukocytes, and by the cytokines secreted by the leukocytes. Fetal-maternal immunological communication also supports pregnancy by inducing physiological changes in the mother. If the mother "misunderstands" the signal sent by the fetus during pregnancy, the fetus will be miscarried or deliver...
Prescott JF, Nicholson VM, Patterson MC, Zandona Meleiro MC, Caterino de Araujo A, Yager JA, Holmes MA.To evaluate use of the virulence-associated protein of Rhodococcus equi in immunizing foals against R equi pneumonia. Methods: Eight (experimental group) and 6 (controls) mares with their foals. Methods: Virulence-associated protein extracted from R equi was used to prepare an acetone-precipitated. Triton X-extracted (APTX) antigen. After determination of the efficacy of passive immunization, in untreated foals or in foals given plasma from a horse vaccinated with APTX antigen or from a nonvaccinated horse, a field trial was done to evaluate the efficacy of vaccination of 8 mares, twice with A...
Romeike A, Brügmann M, Drommer W.Despite extensive clinical research, the etiology of equine recurrent uveitis (ERU) is still unknown. After an immunologic pathogenesis was established in recurrent uveitis in humans, a similar pathogenic mechanism was assumed to exist in ERU. To investigate whether immunopathologic mechanisms are involved in ERU, 20 eyes of 15 horses with ERU were examined immunohistochemically with a T cell marker, B cell marker, and anti-major histocompatibility complex (MHC) class II antibodies. Twenty-six eyes of 20 horses were used for investigation of MHC class II antigen expression in normal equine eye...
Fernández-Bellon H, Solano-Gallego L, Bardagí M, Alberola J, Ramis A, Ferrer L.Leishmania infantum infection has recently been described in horses in Europe. We report the results of a study on the immune response to L. infantum in horses living in an area endemic for leishmaniosis in NE Spain. Two ELISAs using protein A and anti-horse IgG conjugates were adapted to measure specific antibodies to L. infantum in horse sera. A lymphocyte proliferation assay (LPA) of peripheral blood mononuclear cells to L. infantum antigen was also performed to detect specific cellular immune response to Leishmania. Anti-L. infantum antibodies were detected in the serum of 16 of the horses...
Bigler NA, Bruckmaier RM, Gross JJ.Maternal care is essential to optimally support survival of the offspring. During evolution of mammalian species, different phenotypes have evolved in relation to gestation length, number, size, and maturation stage of the offspring at parturition, as well as colostrum and milk composition. The aim of the present review is to describe relationships between placental function and colostrum and milk composition in different mammalian species. Species covered in this article include humans, rabbits, rodents (rat and mouse), carnivores (cats and dogs), and a variety of ungulate species (cattle, sh...
Sciorsci RL, Lillo E, Occhiogrosso L, Rizzo A.Ozone (O) is a triatomic form of oxygen. As O rapidly dissociates into water and releases a reactive form of oxygen that may oxidize cells, the gas mixture of O/O is used in medicine. ATP is widely available for cellular activity. O can be administered via the systemic and local routes. Although O is known as one of the most powerful oxidants, it also promotes antioxidant enzymes. Additionally, it stimulates some of the cells of the immune system and inactivates pathogens, including bacteria, fungi, yeasts, protozoa, and viruses. Owing to these activities, O is used to improve several diseases...
Hines MT, Schott HC, Bayly WM, Leroux AJ.Exercise has been recognized as a stress, which can significantly alter the host's immune response and, therefore, its susceptibility to disease. Whereas research in this area has previously focused primarily on human subjects and laboratory animals, it has more recently extended to domestic animals, especially the equine athlete. Despite several studies, defining the relationship among exercise, the immune response, and disease has proven difficult due to a number of factors, including the complexity of the immune system and the variable nature of exercise itself. It now appears that exercise...
Karagianni AE, Lisowski ZM, Hume DA, Scott Pirie R.The mononuclear phagocyte system (MPS) is a family of cells of related function that includes bone marrow progenitors, blood monocytes and resident tissue macrophages. Macrophages are effector cells in both innate and acquired immunity. They are a major resident cell population in every organ and their numbers increase in response to proinflammatory stimuli. Their function is highly regulated by a wide range of agonists, including lymphokines, cytokines and products of microorganisms. Macrophage biology has been studied most extensively in mice, yet direct comparisons of rodent and human macro...
Franck T, Grulke S, Deby-Dupont G, Deby C, Duvivier H, Peters F, Serteyn D.Equine inflammatory disease is accompanied by a neutrophil activation resulting in the release of granulocytic enzyme myeloperoxidase (MPO). To measure MPO in horse plasma as marker of neutrophil activation, the authors purified equine neutrophil MPO and developed a specific enzyme immunoassay using 2 specific polyclonal antibodies obtained from rabbit (primary antibody) and guinea pig (secondary antibody). The sandwich complex "primary antibody-MPO-secondary antibody" was detected using a goat anti-guinea pig immunoglobulin antibody conjugated to alkaline phosphatase. The enzyme-linked immuno...
Patton KM, McGuire TC, Fraser DG, Hines SA.The goal of this research was to examine the role of cytotoxic T lymphocytes (CTL) in the control of Rhodococcus equi and specifically to determine if R. equi-specific CD8+ CTL occurred in the blood of immune horses. Equine peripheral blood mononuclear cells stimulated with antigen-presenting cells either infected with R. equi or exposed to soluble R. equi antigen lysed R. equi-infected target cells. Lysis was decreased to background by depletion of either CD2+ or CD3+ cells, indicating that the effector cell had a T-lymphocyte, but not NK cell, phenotype. Stimulation induced an increased perc...
Castagnolli KC, de Figueiredo LB, Santana DA, de Castro MB, Romano MA, Szabó MP.Acquired immunity of horses to larvae, nymphs and adults of the Amblyomma cajennense tick was evaluated through three consecutive experimental infestations of tick-bite naïve hosts. Data from these infestations were compared to those from field-sensitized horses and donkeys. It was observed that tick-bite naïve horses developed a low level of resistance after two infestations as shown by a significant decrease in larval yield and a tendency for lower engorged weight of nymphs during third infestation. Ticks fed on field-sensitized horses had a similar biological performance to that observed ...
van der Meulen KM, Nauwynck HJ, Pensaert MB.Equine herpesvirus-1 (EHV-1) may cause abortion in vaccination- and infection-immune horses. EHV-1-infected peripheral blood mononuclear cells (PBMCs) play an important role in virus immune evasion. The mechanisms by which infected PBMCs can avoid destruction by EHV-1-specific antibody and equine complement were examined. The majority of EHV-1-infected PBMCs (68.6 %) lacked surface expression of viral antigens and these cells were not susceptible to complement-mediated lysis. In infected PBMCs with surface expression of viral antigens, 63 % showed focal surface expression, whereas 37 % showed ...
