RNA, or ribonucleic acid, is a fundamental molecule involved in various biological processes in horses, including gene expression, protein synthesis, and regulation of cellular activities. RNA plays a critical role in translating genetic information from DNA into proteins, which are essential for maintaining cellular function and overall health in horses. There are different types of RNA, such as messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each serving distinct functions within the cell. Research on RNA in horses focuses on understanding its role in development, disease mechanisms, and potential therapeutic applications. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and implications of RNA in equine biology and health.
Dahlgren AR, Knych HK, Arthur RM, Durbin-Johnson BP, Finno CJ.Recombinant human erythropoietin (rHuEPO) is a well-known performance enhancing drug in human athletes, and there is anecdotal evidence of it being used in horse racing for the same purpose. rHuEPO, like endogenous EPO, increases arterial oxygen content and thus aerobic power. Micro-doping, or injecting smaller doses over a longer period of time, has become an important concern in both human and equine athletics since it is more difficult to detect. Horses offer an additional challenge of a contractile spleen, thus large changes in the red blood cell mass occur naturally. To address the challe...
Rudolf Vegas A, Podico G, Canisso IF, Bollwein H, Almiñana C, Bauersachs S.During the period of maternal recognition of pregnancy (MRP) in the mare, the embryo needs to signal its presence to the endometrium to prevent regression of the corpus luteum and prepare for establishment of pregnancy. This is achieved by mechanical stimuli and release of various signaling molecules by the equine embryo while migrating through the uterus. We hypothesized that embryo's signals induce changes in the endometrial gene expression in a highly cell type-specific manner. A spatiotemporal transcriptomics approach was applied combining laser capture microdissection and low-input-RNA se...
Bou T, Han H, Mongke T, Zhao R, La X, Ding W, Jia Z, Liu H, Tiemuqier A, An T, Dugarjaviin M, Bai D.The heterogeneity and plasticity of muscle fibers are essential for the athletic performance of horses, mainly at the adaption of exercises and the effect on muscle diseases. Skeletal muscle fibers can be generally distinguished by their characteristics of contraction as slow and fast type myofibers. The diversity of contractile properties and metabolism enable skeletal muscles to respond to the variable functional requirements. We investigated the muscle fiber composition and metabolic enzyme activities of splenius muscle and gluteus medius muscle from Mongolian horses. The deep RNA-seq analy...
Holl HM, Armstrong C, Galantino-Homer H, Brooks SA.Laminitis results in impaired tissue integrity and Inflammation of the epidermal and dermal lamellae connecting the hoof capsule to the underlying distal phalanx and causes loss-of-use, poor quality of life and euthanasia in horses. Historically, studies to better understand the etiology of laminitis by documenting changes in gene expression were hampered by the paucity of gene annotation specific to hoof tissues. Next-generation sequencing enables improvements to annotation by incorporating equine- and hoof-specific transcripts. Here we characterize the hoof lamellar tissue transcriptome of n...
Faber E, Tshilwane SI, Van Kleef M, Pretorius A.Expanding on our previous work, this study used transcriptome analysis of RNA sequences to investigate the various factors that contributed to either inducing apoptosis that resulted in cell death or promoting the survival of African horse sickness virus serotype 4 (AHSV4)-infected horse peripheral blood mononuclear cells (PBMC) after 24 h. Apoptosis is a host defense mechanism that prevents virus replication, accumulation and spread of progeny viruses. AHSV4-infected PBMC were killed via the intrinsic and the perforin/granzyme pathways of apoptosis during the attenuated AHSV4 (attAHSV4) in v...
Suchan T, Kusliy MA, Khan N, Chauvey L, Tonasso-Calvière L, Schiavinato S, Southon J, Keller M, Kitagawa K, Krause J, Bessudnov AN, Bessudnov AA....DNA hybridization-capture techniques allow researchers to focus their sequencing efforts on preselected genomic regions. This feature is especially useful when analysing ancient DNA (aDNA) extracts, which are often dominated by exogenous environmental sources. Here, we assessed, for the first time, the performance of hyRAD as an inexpensive and design-free alternative to commercial capture protocols to obtain authentic aDNA data from osseous remains. HyRAD relies on double enzymatic restriction of fresh DNA extracts to produce RNA probes that cover only a fraction of the genome and can serve a...
Klein C, Bruce P, Hammermueller J, Hayes T, Lillie B, Betteridge K.The current study used RNA sequencing to determine transcriptional profiles of equine endometrium collected 14, 22, and 28 days after ovulation from pregnant mares. In addition, the transcriptomes of endometrial samples obtained 20 days after ovulation from pregnant mares, and from non-pregnant mares which displayed and failed to display extended luteal function following the administration of oxytocin, were determined and compared in order to delineate genes whose expressions depend on the presence of the conceptus as opposed to elevated progesterone alone. A mere fifty-five transcripts were ...
Goszczynski DE, Tinetti PS, Choi YH, Hinrichs K, Ross PJ.Embryonic genome activation is a critical event in embryo development, in which the transcriptional program of the embryo is initiated. The timing and regulation of this process are species-specific. In vitro embryo production is becoming an important clinical and research tool in the horse; however, very little is known about genome activation in this species. The objective of this work was to identify the timing of genome activation, and the transcriptional networks involved, in in vitro-produced horse embryos. RNA-Seq was performed on oocytes and embryos at eight stages of development (MII,...
Goszczynski DE, Tinetti PS, Choi YH, Ross PJ, Hinrichs K.Embryonic genome activation and dosage compensation are major genetic events in early development. Combined analysis of single embryo RNA-seq data and parental genome sequencing was used to evaluate parental contributions to early development and investigate X-chromosome dynamics. In addition, we evaluated dimorphism in gene expression between male and female embryos. Evaluation of parent-specific gene expression revealed a minor increase in paternal expression at the 4-cell stage that increased at the 8-cell stage. We also detected eight genes with allelic expression bias that may have an imp...
Chen Y, Cai S, Zhang Y, Lai Z, Zhong L, Sun X, Li S, Lu G.Equine hepacivirus (EqHV) is a newly discovered hepatitis C virus-like virus that can infect equines. EqHV strains circulating worldwide have been classified into subtypes 1-3. In previous studies, we detected the presence of EqHV strains of subtype 1 and 3 in China. To determine whether EqHV strains of subtype 2 are prevalent in China, serum samples were collected from 133 racehorses in Guangdong province in 2021 and were tested for EqHV RNA by RT-PCR, and the positive rate was 9% (12/133). Sequencing of the NS3 gene revealed that one field strain (GD2021) had a high degree of genetic similar...
McGregor BL, Rozo-Lopez P, Davis TM, Drolet BS.Vesicular stomatitis (VS) is a reportable viral disease which affects horses, cattle, and pigs in the Americas. Outbreaks of vesicular stomatitis virus New Jersey serotype (VSV-NJ) in the United States typically occur on a 5-10-year cycle, usually affecting western and southwestern states. In 2019-2020, an outbreak of VSV Indiana serotype (VSV-IN) extended eastward into the states of Kansas and Missouri for the first time in several decades, leading to 101 confirmed premises in Kansas and 37 confirmed premises in Missouri. In order to investigate which vector species contributed to the outbrea...
James S, Schuijers J, Daffy J, Cook J, Samiric T.Fluoroquinolones are an effective, broad-spectrum antibiotic used to treat an array of bacterial infections. However, they are associated with an increased risk of tendinopathy and tendon rupture even after discontinuation of treatment. This condition is known as fluoroquinolone-associated tendinopathy, the underlying mechanisms of which are poorly understood. While many factors may be involved in the pathophysiology of tendinopathies in general, changes in tenocyte metabolism and viability, as well as alteration of proteoglycan metabolism are prominent findings in the scientific literature. T...
Liu G, Cao W, Salawudeen A, Zhu W, Emeterio K, Safronetz D, Banadyga L.Vesicular stomatitis virus (VSV), which belongs to the Vesiculovirus genus of the family Rhabdoviridae, is a well studied livestock pathogen and prototypic non-segmented, negative-sense RNA virus. Although VSV is responsible for causing economically significant outbreaks of vesicular stomatitis in cattle, horses, and swine, the virus also represents a valuable research tool for molecular biologists and virologists. Indeed, the establishment of a reverse genetics system for the recovery of infectious VSV from cDNA transformed the utility of this virus and paved the way for its use as a vaccine ...
Higuera A, Herrera G, Jimenez P, García-Corredor D, Pulido-Medellín M, Bulla-Castañeda DM, Pinilla JC, Moreno-Pérez DA, Maloney JG, Santín M.... is frequently reported in fecal samples from animals and humans worldwide, and a variety of subtypes (STs) have been observed in wild and domestic animals. In Colombia, few studies have focused on the transmission dynamics and epidemiological importance of in animals. In this study, we characterized the frequency and subtypes of in fecal samples of domestic animals including pigs, minipigs, cows, dogs, horses, goats, sheep, and llama from three departments of Colombia. Of the 118 fecal samples included in this study 81.4% ( = 96) were positive for using a PCR that amplifies a fragment of t...
Ferreira JRM, Villela SB, Bianconi C, Ormieres M, de Melo GD, Pugliesi G, Gobesso AAO.Different approaches have been used to improve conception rates at foal heat. Omega-3 fatty acids family and derivatives have improved reproductive efficiency in ruminants, but literature lacks studies evaluating these components on equines. The objective of this study was to evaluate effects of mare dietary supplementation with microalgae rich in docosahexaenoic acid (DHA) during peripartum on follicular dynamics and uterine involution in early post-partum. Eighteen pregnant mares, no particular breed, 410 ± 39.5 kg body weight (BW), and 7.83 ± 2.01 yr old were used. Mares were randomly ass...
Mok CH, MacLeod JN.Within developing synovial joints, interzone and anlagen cells progress through divergent chondrogenic pathways to generate stable articular cartilage and transient hypertrophic anlagen cartilage, respectively. Understanding the comparative cell biology between interzone and anlagen cells may provide novel insights into emergent cell-based therapies to support articular cartilage regeneration. The aim of this study was to assess the kinetics of gene expression profiles in these skeletal cell lines after inducing chondrogenesis in culture. Interzone and anlagen cells from seven equine fetuses w...
West Nile virus (WNV) is one of the most widely distributed (re-)emerging arboviruses. In Croatia, acute WNV infections as well as seropositivity were detected in humans, horses, birds and poultry. Although serologic evidence of WNV human infections dates back to the 1970s, no clinical cases were reported until 2012. WNV outbreaks, as well as sporadic infections, were continuously recorded in continental Croatian counties from 2012 to 2018. In addition, acute asymptomatic infections (IgM antibodies) in horses have been regularly notified in continental regions since 2012, while seropositive ho...
Drolet BS, Reeves WK, Bennett KE, Pauszek SJ, Bertram MR, Rodriguez LL.In 2006, vesicular stomatitis New Jersey virus (VSNJV) caused outbreaks in Wyoming (WY) horses and cattle after overwintering in 2004 and 2005. Within two weeks of the outbreak onset, 12,203 biting flies and 194 grasshoppers were collected near three equine-positive premises in Natrona County, WY. Insects were identified to the species level and tested by RT-qPCR for VSNJV polymerase (L) and phosphoprotein (P) gene RNA. Collected dipterans known to be competent for VSV transmission included Simulium black flies and Culicoides biting midges. VSNJV L and P RNA was detected in two pools of female...
Jakobsen JR, Schjerling P, Svensson RB, Buhl R, Carstensen H, Koch M, Krogsgaard MR, Kjær M, Mackey AL.The myotendinous junction (MTJ) is a specialized interface for transmitting high forces between the muscle and tendon and yet the MTJ is a common site of strain injury with a high recurrence rate. The aim of this study was to identify previously unknown MTJ components in mature animals and humans. Samples were obtained from the superficial digital flexor (SDF) muscle-tendon interface of 20 horses, and the tissue was separated through a sequential cryosectioning approach into muscle, MTJ (muscle tissue enriched in myofiber tips attached to the tendon), and tendon fractions. RT-PCR was performed...
Ortega Granda O, Valle C, Shannon A, Decroly E, Canard B, Coutard B, Rabah N.Venezuelan equine encephalitis virus (VEEV) is a reemerging arthropod-borne virus causing encephalitis in humans and domesticated animals. VEEV possesses a positive single-stranded RNA genome capped at its 5' end. The capping process is performed by the nonstructural protein nsP1, which bears methyl and guanylyltransferase activities. The capping reaction starts with the methylation of GTP. The generated mGTP is complexed to the enzyme to form an mGMP-nsP1 covalent intermediate. The mGMP is then transferred onto the 5'-diphosphate end of the viral RNA. Here, we explore the specificities of the...
Karagianni AE, Eaton SL, Kurian D, Cillán-Garcia E, Twynam-Perkins J, Raper A, Wishart TM, Pirie RS.Airway inflammation is highly prevalent in horses, with the majority of non-infectious cases being defined as equine asthma. Currently, cytological analysis of airway derived samples is the principal method of assessing lower airway inflammation. Samples can be obtained by tracheal wash (TW) or by lavage of the lower respiratory tract (bronchoalveolar lavage (BAL) fluid; BALF). Although BALF cytology carries significant diagnostic advantages over TW cytology for the diagnosis of equine asthma, sample acquisition is invasive, making it prohibitive for routine and sequential screening of airway ...
Stefanetti V, Pascucci L, Wilsher S, Cappelli K, Capomaccio S, Reale L, Passamonti F, Coletti M, Crociati M, Monaci M, Marenzoni ML.Endogenous retroviruses (ERVs) are proviral phases of exogenous retroviruses, which have coevolved with vertebrate genomes for millions of years. The conservation of ERV genes throughout evolution suggests their beneficial effects on their hosts' survival. An example of such positive selection is demonstrated by the syncytin gene, which encodes a protein with affinity for various mammalian placentas that is involved in the formation of syncytiotrophoblasts. Although the horse has an epitheliochorial placenta, in which the fetal trophoblasts are simply apposed to the intact uterine epithelium, ...
Non-primate hepacivirus (NPHV) is a homolog of hepatitis C virus and has been isolated from dogs and horses. Data on NPHV prevalence and distribution are not complete, and there is a particular lack of reports from the African continent. The present study represents the first investigation of NPHV prevalence in horses and dogs in North Africa. Blood was collected from 172 horses and 36 dogs at different locations in Morocco, and screened for NPHV RNA using nested PCR targeting 5'UTR and NS3 regions and analyzed for anti-NPHV NS3 antibody using a Gaussia luciferase immunoprecipitation system-to...
Morris ERA, Boyle AG, Riihimäki M, Aspán A, Anis E, Hillhouse AE, Ivanov I, Bordin AI, Pringle J, Cohen ND.Streptococcus equi subsp. equi (SEE) is a host-restricted bacterium that causes the common infectious upper respiratory disease known as strangles in horses. Perpetuation of SEE infection appears attributable to inapparent carrier horses because it neither persists long-term in the environment nor infects other host mammals or vectors, and infection results in short-lived immunity. Whether pathogen factors enable SEE to remain in horses without causing clinical signs remains poorly understood. Thus, our objective was to use next-generation sequencing technologies to characterize the genome, me...
Tomlinson JE, Wolfisberg R, Fahnøe U, Patel RS, Trivedi S, Kumar A, Sharma H, Nielsen L, McDonough SP, Bukh J, Tennant BC, Kapoor A, Rosenberg BR....Equine hepacivirus (EqHV) is phylogenetically the closest relative of HCV and shares genome organization, hepatotropism, transient or persistent infection outcome, and the ability to cause hepatitis. Thus, EqHV studies are important to understand equine liver disease and further as an outbred surrogate animal model for HCV pathogenesis and protective immune responses. Here, we aimed to characterize the course of EqHV infection and associated protective immune responses. Seven horses were experimentally inoculated with EqHV, monitored for 6 months, and rechallenged with the same and, subsequen...
Jiang Z, Chen JW, Haughan J, Stefanovski D, Soma LR, Robinson MA.Extracorporeal shockwave therapy (ESWT) is a treatment applied to musculoskeletal injuries in equine athletes to alleviate pain and accelerate healing. ESWT also causes acute tissue damage. Therefore, its ability to act as an analgesic and cause tissue damage potentially increases the risk of a catastrophic event if used shortly before a strenuous competition such as horseracing. While ESWT is prohibited by many racing jurisdictions within 10 days prior to competition, a test to detect whether a horse has received ESWT is needed. ESWT changes the protein levels of inflammatory mediators in bl...
Ibrahim S, Hedia M, Taqi MO, Derbala MK, Mahmoud KGM, Ahmed Y, Ismail S, El-Belely M.So far the intimate link between serum microRNA (miRNA) and uterine inflammation in mares is unknown. We aimed (I) to investigate expression profile of eca-miR-155, eca-miR-223, eca-miR-17, eca-miR-200a, and eca-miR-205 (II) and to measure concentrations of interleukin 6 (IL-6), and prostaglandins (PGF and PGE) in serum of mares with healthy and abnormal uterine status (endometritis). This study was conducted on 80 Arabian mares: young (4-7 years), and old (8-14 years). Mares were divided into 48 sub-fertile (endometritis) and 32 fertile (control) at stud farms. Serum was collected for measuri...
Weber KS, Wagener K, Blanco M, Bauersachs S, Bollwein H.Subfertility is a major problem in modern horse breeding. Especially, mares without clinical signs of reproductive diseases, without known uterine pathogens and no evidence of inflammation but not becoming pregnant after several breeding attempts are challenging for veterinarians. To obtain new insights into the cause of these fertility problems and aiming at improving diagnosis of subfertile mares, a comparative analysis of the intrauterine transcriptome in subfertile and fertile mares was performed. Uterine cytobrush samples were collected during estrus from 57 mares without clinical signs o...
Boakari YL, Esteller-Vico A, Loux S, El-Sheikh Ali H, Fernandes CB, Dini P, Scoggin KE, Cray C, Ball BA.Serum amyloid A (SAA) and Haptoglobin (Hp) are acute phase proteins, produced during inflammation, such as placentitis. In horses, SAA and SAA1 are protein coding genes. Objectives were to analyze SAA and Hp concentrations and relative abundance of SAA, SAA1 and Hp mRNA transcript in maternal and fetal tissues after experimental induction of placentitis or mares of a control group. Serum Amyloid A family proteins were in marked abundance in the stroma of the endometrium and chorioallantois associated with inflammatory cells. Maternal plasma SAA concentrations were greater (P = 0.01) in mares w...
Du Cheyne C, Chen Y, De Craene J, Thas O, De Spiegelaere W.Accurate tools to measure RNA integrity are essential to obtain reliable gene expression data. The reverse transcription quantitative PCR (RT-qPCR) based 3':5' assay permits a direct determination of messenger RNA (mRNA) integrity. However, the use of standard curves and the possible effect of PCR inhibitors make this method cumbersome and prone to variation, especially in small samples. Here we developed a triplex digital PCR (dPCR) 3':5' assay for assessing RNA integrity in equine samples as rapid and simple alternative to RT-qPCR. This dPCR assay not only provides a straight forward analysi...
LaPolt PS, Tilly JL, Aihara T, Nishimori K, Hsueh AJ.The actions of gonadotropins on ovarian differentiation are associated with dynamic changes in gonadotropin receptor content, presumably due to modulation of receptor gene expression. The present studies used a reverse transcription-polymerase chain reaction to obtain a rat FSH receptor cDNA fragment, followed by synthesis of a labeled cRNA probe to examine the regulation of FSH receptor mRNA levels during follicular maturation, ovulation, and luteinization. Northern blot analysis of ovarian RNA with the FSH receptor probe revealed two predominant hybridization signals of 7.0 and 2.5 kilobases...
Binz T, Lebelt J, Niemann H, Hagenau K.By reverse transcriptase/PCR amplification and subsequent sequence determination of the p24 gene, the relatedness of Borna disease virus (BDV) in various naturally infected animal species was determined. These results are indicative of a common ancestral virus pool and a remarkably low species barrier of BDV. Comparison of 11 sequences to that of tissue culture adapted virus revealed that the homology among all isolates was at least 96.2% at the nucleotide level, and 97% at the amino acid level. Viral sequences from sheep, donkey and horse were found to be not more distantly related to each ot...
Kishi M, Arimura Y, Ikuta K, Shoya Y, Lai PK, Kakinuma M.A cDNA fragment of the Borna disease virus (BDV) open reading frame II (ORF-II), which encodes a 24-kDa phosphoprotein (p24 [P protein]), was amplified from total RNA of peripheral blood mononuclear cells (PBMC) from three psychiatric inpatients. The amplified cDNA fragments were cloned, sequenced, and analyzed. A total of 15 clones, 5 from each patient, were studied. Intrapatient divergencies of the BDV ORF-II nucleotide sequence were 4.2 to 7.3%, 4.8 to 7.3%, and 2.8 to 7.1% for the three patients, leading to differences of 7.7 to 14.5%, 10.3 to 17.1%, and 6.0 to 16.2%, respectively, in the ...
Salim B, Bakheit MA, Kamau J, Nakamura I, Sugimoto C.This is a molecular epidemiological investigation on Theileria equi, a causative agent of equine piroplasmosis. Blood samples were collected from 127 horses from different geographical locations in Sudan. The small subunit of rRNA gene (18S; ~1,600 bp) was amplified from 20 positive field samples and subsequently subjected to direct sequencing and analysis to reveal possible strain differences and the presence of a novel species or genotypes. Sequences were compared with published sequences mainly from South African and Spanish isolates. Eleven distinct T. equi sequences within 18S rRNA gene w...
Smits K, De Coninck DI, Van Nieuwerburgh F, Govaere J, Van Poucke M, Peelman L, Deforce D, Van Soom A.Although the equine oviduct clearly affects early embryo development and the selective transport of equine embryos through the oviduct indicates a reciprocal interaction, the influence of the embryo on gene expression in the oviduct remains to be determined in the horse. The aim of this study was to examine this by means of RNA sequencing. Four days after ovulation, epithelial cells ipsilateral and contralateral to the ovulation side from five cyclic and five pregnant mares were collected from the oviduct. RNA was extracted, samples were sequenced, and data analysis was performed to determine ...
David F, Farley J, Huang H, Lavoie JP, Laverty S.To evaluate mRNA expression of several proinflammatory and anti-inflammatory cytokines and chemokines in equine unstimulated and interleukin-1beta (IL-1beta)-stimulated chondrocytes. Methods: In vitro experiment using equine chondrocyte cultures. Methods: Whole articular cartilage from metacarpophalangeal joints (n=5 horses; 10 fetlocks). Methods: Chondrocyte monolayer cultures were established from digested adult equine articular cartilage and stimulated with 5 ng/mL of recombinant human IL-1beta. RNA was extracted from the cells 24 hours after stimulation. IL-1beta, IL-4, IL-6, IL-8, tumor n...
Glynn ER, Londono AS, Zinn SA, Hoagland TA, Govoni KE.The use of equine bone marrow mesenchymal stem cells (BMSC) is a novel method to improve fracture healing in horses. However, additional research is needed to identify optimal culture conditions and to determine the mechanisms involved in regulating BMSC differentiation into osteoblasts. The objectives of the experiments were to determine: 1) if autologous or commercial serum is better for proliferation and differentiation of equine BMSC into osteoblasts, and 2) the expression of key transcription factors during the differentiation of equine BMSC into osteoblasts. Equine BMSC were isolated fro...
Li B, He X, Zhao Y, Bai D, Du M, Song L, Liu Z, Yin Z, Manglai D.Horse testis development and spermatogenesis are complex physiological processes. To study these processes, three immature and three mature testes were collected from the Mongolian horse, and six libraries were established using high-throughput RNA sequencing technology (RNA-Seq) to screen for genes related to testis development and spermatogenesis. A total of 16,237 upregulated genes and 8,641 downregulated genes were detected in the testis of the Mongolian horse. These genes play important roles in different developmental stages of spermatogenesis and testicular development. Five genes with ...
Padoan E, Ferraresso S, Pegolo S, Castagnaro M, Barnini C, Bargelloni L.The goal of the present study was to investigate mRNA expression levels of several cytokines and inflammatory mediators in broncho-alveolar lavage (BAL) fluid and respiratory epithelium in recurrent airway obstruction (RAO)-affected horses. RAO, also called heaves, is a common, performance-limiting, equine respiratory disease with clinical signs and pathophysiological similarities to human asthma, and characterized by bronchospasm, neutrophilic infiltration and increased mucus in the airways. Six RAO-affected horses were examined twice within 15 days and seven clinically healthy horses were ex...
Pacholewska A, Jagannathan V, Drögemüller M, Klukowska-Rötzler J, Lanz S, Hamza E, Dermitzakis ET, Marti E, Leeb T, Gerber V.Recurrent airway obstruction (RAO) is a common and potentially debilitating lower airway disease in horses, which shares many similarities with human asthma. In susceptible horses RAO exacerbation is caused by environmental allergens and irritants present in hay dust. The objective of this study was the identification of genes and pathways involved in the pathology of RAO by global transcriptome analyses in stimulated peripheral blood mononuclear cells (PBMCs). We performed RNA-seq on PBMCs derived from 40 RAO affected and 45 control horses belonging to three cohorts of Warmblood horses: two h...
Hughes KJ, Nicolson L, Da Costa N, Franklin SH, Allen KJ, Dunham SP.Inflammatory airway disease (IAD) is a common disorder of performance horses and is associated with poor performance and accumulation of mucus and inflammatory cells in lower airway secretions. Horses with IAD frequently have increased relative counts of neutrophils in bronchoalveolar lavage fluid (BALF); less commonly relative counts of eosinophils and/or mast cells may be increased. The aetiopathogenesis of IAD is unknown and may involve innate and/or acquired immune responses to various factors including respirable dust constituents, micro-organisms, noxious gases and unconditioned air. The...
Ellis SA, Martin AJ, Holmes EC, Morrison WI.Nineteen horse MHC class I specificities have been serologically identified previously at a single locus (ELA-A), and two other specificities appear to be coded at other loci. Biochemical studies indicate that there are at least two expressed loci. In order to establish the number of transcribed horse MHC class I genes, we made a cDNA library from a heterozygous animal (ELA-A3/A7), and screened for positive clones using a bovine class I probe. More than 200 class I clones were isolated in this way, and so far seven unique full length sequences have been identified. All of the sequences are pre...
Nichols AEC, Settlage RE, Werre SR, Dahlgren LA.Tendinopathies are common and difficult to resolve due to the formation of scar tissue that reduces the mechanical integrity of the tissue, leading to frequent reinjury. Tenocytes respond to both excessive loading and unloading by producing pro-inflammatory mediators, suggesting that these cells are actively involved in the development of tendon degeneration. The transcription factor scleraxis (Scx) is required for the development of force-transmitting tendon during development and for mechanically stimulated tenogenesis of stem cells, but its function in adult tenocytes is less well-defined. ...
Leise BS, Faleiros RR, Watts M, Johnson PJ, Black SJ, Belknap JK.There is a need to assess the laminar inflammatory response in a laminitis model that more closely resembles clinical cases of sepsis-related laminitis than the black walnut extract (BWE) model. Objective: To determine if a similar pattern of laminar inflammation, characterised by proinflammatory cytokine expression, occurs in the CHO model of laminitis as has been previously reported for the BWE model. Methods: Sixteen horses administered 17.6 g of starch (85% corn starch/15% wood flour)/kg bwt via nasogastric (NG) tube were anaesthetised either after developing a temperature>38.9°C (DEV ...
Rakic R, Bourdon B, Hervieu M, Branly T, Legendre F, Saulnier N, Audigié F, Maddens S, Demoor M, Galera P.As in humans, osteoarthritis (OA) causes considerable economic loss to the equine industry. New hopes for cartilage repair have emerged with the matrix-associated autologous chondrocyte implantation (MACI). Nevertheless, its limitation is due to the dedifferentiation occurring during the chondrocyte amplification phase, leading to the loss of its capacity to produce a hyaline extracellular matrix (ECM). To enhance the MACI therapy efficiency, we have developed a strategy for chondrocyte redifferentiation, and demonstrated its feasibility in the equine model. Thus, to mimic the cartilage microe...
Attoui H, Sailleau C, Mohd Jaafar F, Belhouchet M, Biagini P, Cantaloube JF, de Micco P, Mertens P, Zientara S.The complete nucleotide sequence of Middelburg virus (MIDV) was determined for strain MIDV-857 from Zimbabwe. The isolation of this virus in 1993 from a horse that died showing severe clinical signs represents the first indication that MIDV can cause severe disease in equids. Full-length cDNA copies of the viral genome were successfully synthesized by an innovative RT-PCR amplification approach using an 'anchor primer' combined with the SMART methodology described previously for the synthesis of full-length cDNA copies from genome segments of dsRNA viruses. The MIDV-857 genome is 11,674 nt, ex...
Matsuu A, Hobo S, Ando K, Sanekata T, Sato F, Endo Y, Amaya T, Osaki T, Horie M, Masatani T, Ozawa M, Tsukiyama-Kohara K.Non-primate hepacivirus (NPHV) is a recently discovered homolog of the hepatitis C virus in horses. The frequency and distribution of NPHV infections among horses in Japan is unknown. In this study, serum samples from 453 horses across Japan were screened for NPHV RNA using real-time RT-PCR and anti-nonstructural 3 protein (NS3) antibodies using the Gaussia luciferase immunoprecipitation system assay. In order to monitor the course of NPHV infection in horses, we examined 31 stored samples (9 adult horses and 22 young horses) obtained one year ago and compared the results to the recent data. S...
Tung JT, Arnold CE, Alexander LH, Yuzbasiyan-Gurkan V, Venta PJ, Richardson DW, Caron JP.To determine the effects of prostaglandin E2 (PGE2) on recombinant equine interleukin (IL)-1beta-stimulated expression of matrix metalloproteinases (MMP 1, MMP 3, MMP 13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP 1) in vitro. Methods: Cultured equine chondrocytes. Methods: Stationary monolayers of first-passage chondrocytes were exposed to graduated concentrations of PGE2 with or without a subsaturating dose (50 pg/ml) of recombinant equine IL-1beta (reIL-1beta) to induce expression of MMP 1, MMP 3, MMP 13, and TIMP 1, followed by RNA isolation and northern blotting. In subseque...
Vandewege MW, Platt RN, Ray DA, Hoffmann FG.PIWI proteins and PIWI-interacting RNAs (piRNAs) are part of a cellular pathway that has evolved to protect genomes against the proliferation of transposable elements (TEs). PIWIs and piRNAs assemble into complexes that are involved in epigenetic and post-transcriptional repression of TEs. Most of our understanding of the mechanisms of piRNA-mediated TE silencing comes from fruit fly and mouse models. However, even in these well-studied animals it is unclear how piRNA responses relate to variable TE expression and whether the strength of the piRNA response affects TE content over time. Here, w...
Figueiredo MD, Salter CE, Andrietti AL, Vandenplas ML, Hurley DJ, Moore JN.Quantification of gene expression using real-time reverse transcription quantitative PCR (RT-qPCR) is a reliable method to monitor cellular responses to pro-inflammatory stimuli. The main objective of this study was to validate a set of equine primer pairs that can be routinely used to monitor expression of genes that are central to inflammatory and immune responses. This paper describes the steps used to optimize and validate 29 equine primer pairs for RT-qPCR assays using SYBR Green detection. To validate these assays, monocytes were isolated from three horses and stimulated with Escherichia...
Molenkamp R, Rozier BC, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the type member of the family Arteriviridae, is a single-stranded RNA virus with a positive-stranded genome of approximately 13 kb. EAV uses a discontinuous transcription mechanism to produce a nested set of six subgenomic mRNAs from which its structural genes are expressed. We have generated the first documented arterivirus defective interfering (DI) RNAs by serial undiluted passaging of a wild-type EAV stock in BHK-21 cells. A cDNA copy of the smallest DI RNA (5.6 kb) was cloned. Upon transfection into EAV-infected BHK-21 cells, transcripts derived from this clo...
Mienaltowski MJ, Huang L, Frisbie DD, McIlwraith CW, Stromberg AJ, Bathke AC, Macleod JN.Full-thickness articular cartilage lesions that reach to the subchondral bone yet are restricted to the chondral compartment usually fill with a fibrocartilage-like repair tissue which is structurally and biomechanically compromised relative to normal articular cartilage. The objective of this study was to evaluate transcriptional differences between chondrocytes of normal articular cartilage and repair tissue cells four months post-microfracture. Methods: Bilateral one-cm2 full-thickness defects were made in the articular surface of both distal femurs of four adult horses followed by subchond...
Pfeiffenberger M, Bartsch J, Hoff P, Ponomarev I, Barnewitz D, Thöne-Reineke C, Buttgereit F, Gaber T, Lang A.Fractures in horses-whether simple fractures with just one clean break, or incomplete greenstick with stress fractures, or complications such as shattered bones can all be either minimal or even catastrophic. Thus, improvement in fracture healing is a hallmark in equine orthopedics. The fracture healing process implements a complex sequence of events including the initial inflammatory phase removing damaged tissue, re-establishment of vessels and mesenchymal stromal cells, a soft and hard callus phase closing the fracture gap as well as the remodeling phase shaping the bone to a scar-free tiss...
Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a uniquely dynamic system in which to study the mechanism and role of genomic variation in lentiviral persistence and pathogenesis. We have used a Shetland pony model of infection to investigate the association of specific long terminal repeat (LTR) and env gene genomic sequences with the initiation of infection and the onset of disease. We analyzed viral RNA isolated from a pathogenic stock of virus (EIAV PV) and from plasma taken during the first disease episode from two ponies infected with EIAV PV. Overall sequence variation within gp90 was lo...
Bogaert L, Van Poucke M, De Baere C, Dewulf J, Peelman L, Ducatelle R, Gasthuys F, Martens A.Equine sarcoids, the most common skin tumours in horses, are induced by bovine papillomavirus (BPV). Their clinical appearance varies from small stable patches to aggressively growing masses. Differences in BPV load and mRNA expression and Ki67 and p53 immunostaining among four clinical types (fibroblastic, occult, nodular and verrucous sarcoids) were evaluated to test the hypothesis that the clinical behaviour of equine sarcoids correlates with BPV activity. Viral load and expression of the BPV E2, E5, E6 and E7 genes were determined using quantitative real-time PCR. The proliferative fractio...
Buechli ME, Lamarre J, Koch TG.MicroRNAs are a class of short noncoding RNAs that are involved in various biological processes, including differentiation. MicroRNA-140 (miR-140) has been identified as a cartilage-specific microRNA with several targets involved in cartilage development and homeostasis. The aim of this study was to investigate the expression of miR-140 during chondrogenic differentiation of equine cord blood-derived mesenchymal stromal cells (eCB-MSCs). We demonstrate both that miR-140 is highly expressed in normal equine articular cartilage and that eCB-MSCs express significantly higher levels of this microR...
Beisel CE, Edwards JF, Dunn LL, Rice NR.Transcription of pathogenic equine infectious anemia virus (EIAV) in an acutely infected horse was examined by using the polymerase chain reaction and nucleotide sequencing. Four spliced transcripts were identified in liver tissue, in contrast to the multiplicity of alternatively spliced messages reported for in vitro-propagated human immunodeficiency virus, simian immunodeficiency virus, and, to a lesser extent, EIAV. Nucleotide sequence analysis demonstrated that three of these mRNAs encode known viral proteins: the envelope precursor, the product of the S2 open reading frame, and the regula...
Bauersachs S, Wolf E.Different reproductive strategies evolved in various mammalian groups to achieve recognition, establishment and maintenance of pregnancy. The complexity of these processes is reflected by a high incidence of embryonic loss during this critical period in many mammalian species. Besides studies in mice and humans a number of transcriptome studies of endometrial tissue samples and also of early embryos have been performed during the pre-implantation phase in cattle, swine and horse to identify genes associated with embryo-maternal interaction. Results of these studies are reviewed and compared be...
Kojima K, Taniguchi K, Kobayashi N.We have sequenced gene 5 encoding NSP1 for three human, two porcine, two bovine, one feline, and five equine rotavirus strains, and compared the nucleotide and deduced amino acid sequences with the published sequences for other various strains. Subgroup I human strains L26, 69M, and DS-1 were found to have a similar NSP1 sequence despite their different G serotypes, VP4 genotypes, and RNA patterns. The NSP1 sequence of the human strain K8 showed a high degree of homology to those of porcine strains OSU and YM. A high degree of homology was found among three equine strains (H2, FI-14, and FI23)...
Mienaltowski MJ, Huang L, Stromberg AJ, MacLeod JN.Articular cartilage undergoes an important maturation process from neonate to adult that is reflected by alterations in matrix protein organization and increased heterogeneity of chondrocyte morphology. In the horse, these changes are influenced by exercise during the first five months of postnatal life. Transcriptional profiling was used to evaluate changes in articular chondrocyte gene expression during postnatal growth and development. Methods: Total RNA was isolated from the articular cartilage of neonatal (0-10 days) and adult (4-5 years) horses, subjected to one round of linear RNA ampli...
