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.
de Santana Evangelista K, de Castro Barbosa E, de Souza Andrade A, Ardisson L, Martins AA, Boasquivis PF, Duarte MM, de Oliveira Ribeiro B....This study establishes an integrated workflow linking antibody production, neutralization assessment, and epitope mapping, supporting the identification of antigenic regions recognized by polyclonal antibodies generated in vivo. The viral suspension was inactivated with β-propiolactone under biosafety level 3 (BSL-3) conditions, with no cytopathic effect or plaque formation observed, confirming loss of viral replicative capacity. The produced immunogen retained antigenic activity, as demonstrated by reactivity with IgG antibodies from vaccinated and previously infected individuals. Protein an...
Domínguez-Odio A, González LIC, Alfonso DM, Martínez ER, Ríos MÁB, Cala-Delgado DL.The international scientific community continues to promote the development of diagnostic techniques with improved performance and novel capture antigens. On this basis, two synthetic peptides derived from gp45 and gp90 were evaluated to identify the best candidate for the indirect immunodetection of infection. In both assays, 68 serum samples from naturally infected horses in Granma Province (59 seropositive and 9 seronegative), previously classified using the agar gel immunodiffusion (AGID) test, were analyzed. The diagnostic performance of each candidate peptide was assessed by calculating ...
Sánchez A, Sánchez P, Sánchez A, Durán G, Solano G, Villalta M, Gómez A, Gutiérrez JM, León G.Variability in the antibody response of horses used for snake antivenom manufacture is well recognized, yet its statistical structure and implications for industrial productivity remain poorly characterized. In this study, we quantified antivenom antibody titers by ELISA in a cohort of 14 horses immunized with venoms from the clinically most important snakes in sub-Saharan Africa. To integrate antibody levels with plasma availability, we calculated the Cumulative Plasma Productivity (CPP) by converting individual plasma volumes into titer-corrected equivalents and sequentially pooling these vo...
Romanucci M, Baghini S, Canonici F, Canonici P, Di Luzio Paparatti F, Marruchella G.Neck masses may represent a diagnostic challenge for equine veterinarians, since they may involve different structures with a similar clinical appearance. Whereas neck masses in foals mostly result from non-neoplastic conditions, including various congenital abnormalities, neoplastic cervical masses have been rarely documented. This report describes the unusual case of a rapidly growing neck cancer in a four-month-old colt, resulting in a fatal outcome. Gross and immunohistological findings were most consistent with a poorly differentiated thymic carcinoma with sarcomatoid features and multifo...
Carmona JU, López C.Tendinopathy involves a dysregulated inflammatory microenvironment in which cytokines, growth factors (GF) and extracellular matrix components interact dynamically. Platelet-rich plasma (PRP) is widely used as a regenerative therapy, but its mechanisms of action in inflamed tendon remain unclear. This study evaluated whether platelet-rich gel supernatant (PRGS) reprograms the inflammatory-anabolic mediator network in an equine in vitro tendon explant system stimulated with lipopolysaccharide (LPS). Tendon explants were cultured under six experimental conditions, including non-stimulated contro...
Moore L, McLain A, McDowell SH, Ledgerwood CJ, Bailie E, Nesbit MA, Moore T.Equine foals receive IgG from mare colostrum through passive transfer. Failure of passive transfer (FPT) is a significant risk to the foal's life, leaving them vulnerable to infection and sepsis. Radial Immunodiffusion (RID) and immunoturbidimetric assays quantify IgG present in a foal sample but require a laboratory to complete. Accurate, reproducible, stall-side testing to rapidly quantify IgG would allow for expedited clinical decisions, with potential to improve equine foal care and survival. Objective: To evaluate the analytical and clinical performance of a stall-side IgG lateral-flow te...
Kanani Y, Oryan A, Derakhshandeh A.Burkholderia mallei is the causative agent of glanders, a serious zoonotic disease of major concern for both animal and human health. This highly contagious and potentially fatal bacterium is always classified as a biothreat agent. In this review, we covered a comprehensive overview of glanders, including the biology of the pathogen, epidemiology, pathogenesis, diagnosis, control strategies and ongoing eradication programs in Eurasia. We also summarized human case reports, differential diagnosis, treatment and organism's antimicrobial properties. The section on vaccine development is among the...
Junuzović M, Troillet A, Burk J.Osteoarthritis (OA) is a cross-species, multifactorial joint disease characterized by the progressive degeneration of articular cartilage, morphological remodeling of the subchondral bone, and inflammatory and fibrotic changes of the joint capsule. These alterations arise from chronic, often subclinical, inflammatory processes and dysregulated cellular homeostasis, leading to profound shifts in the cellular and extracellular composition of the joint organ. Although the mechanisms driving persistent inflammation are only partially understood, their impact on all joint-associated tissues is well...
Utrilla-Trigo S, Jiménez-Cabello L, van Gennip RGP, van Rijn PA, Ortego J, Calvo-Pinilla E.African horse sickness (AHS) is a highly severe, midge-borne disease of equids showing a mortality rate of > 90% in naive domestic horses. Outbreaks are caused by AHS virus (AHSV) and result in devastating economic losses in developing countries as equids play a crucial role in the agricultural industry and many households. The AHSV species encompasses nine serotypes showing no or limited cross protection, which is challenging regarding AHS vaccine development. Recently, and like bluetongue virus (BTV), the AHS Disabled Infectious Single Animal (DISA)-DIVA vaccine platform was developed...
Yang Q, Lopez MJ.Progenitor cell epithelial to mesenchymal transition (EMT) could impact healing in the epidermal-dermal junction of the equine hoof stratum internum (SI). The hypothesis of this study was that K14 + CD105+ equine hoof SI progenitor cells assume a mesenchymal phenotype in the presence of inflammatory interleukins in vitro. Methods: K14 + CD105+ progenitor cell percentages isolated from proliferative scarred (fibrous) and healthy SI were quantified. Decellularized matrix was prepared from and K14 + CD105+ cells localized in healthy SI. Gene expression (CD44, CD105, E-cadherin, N-cadh...
Malsa J, Chereau A, Guégnard F, Serreau D, Gesbert A, Reigner F, Chamoin L, Guillot J, Vernudachi A, Mach N, Fleurance G, Lacroix-Lamandé S....The emergence of anthelmintic-resistant parasite isolates necessitates alternative control strategies. The use of dietary additives with anti-parasitic or immunomodulatory activities has been proposed as a solution, but whether such additives can simultaneously exert dual bioactivities within this context has rarely been explored. Here, we evaluated whether selected terpenes could exert dual bioactivities (anti-parasitic and immunomodulatory) with a view to their use as food additives that can limit strongyle infections in horses. In vitro tests with cyathostomin larval development, larval mig...
Lungren L, Mazzarella J, Mumbauer-Pisano J.This qualitative study explored healthcare students' lived experiences during an interprofessional education (IPE) event incorporating equine-assisted services (EAS). Traditional IPE events often rely on classroom settings that may limit interprofessional engagement, collaboration, and application. Utilizing interpretive phenomenological analysis, researchers examined how the equine environment influenced interprofessional learning among fourteen graduate students from diverse healthcare disciplines at a western United States public university. Participants engaged in experiential demonstratio...
Holmes CM, Babasyan S, Wagner B.Equine herpesvirus type 1 (EHV-1) is a high morbidity and mortality virus that impacts horse populations worldwide. As a respiratory virus, it enters through the upper respiratory tract (URT), where mucosal immunity plays a crucial role in preventing severe disease. In this study, flow cytometry was used to characterize the nasal leukocyte population during EHV-1 infection, and RNA sequencing of nasal secretions was employed to assess transcriptional markers of the mucosal immune response. Horses with distinct immune statuses were compared at four stages: pre-infection, early (day 1 and 3 post...
Gluck-Flynn CR, Han H, Valenzuela M, Routh P, Ostland VE, Pratt-Phillips SE.Hepcidin (Hepc) is a peptide hormone primarily produced by hepatocytes and considered the master regulator of iron homeostasis, with Hepc controlling the release of iron within the circulation. Despite the renewed interest in iron-related research due to Hepc discovery, there is limited data on serum hepcidin in horses. The objective of the study was to develop and partially validate a competitive enzyme-linked immunosorbent assay (ELISA) to quantify serum hepcidin in horses. Precision was evaluated using horse serum samples representing low, medium and high Hepc concentrations, yielding intra...
Sjolin E, Zakia LS, Galezowski A, Whitehead AE.Literature on the seroprevalence of antibodies to the causative agents of equine protozoal myeloencephalitis (EPM) in Canada is limited. Objective: To determine the prevalence of serum antibodies against Sarcocystis neurona and Neospora hughesi in apparently healthy horses without signs of neurologic disease which have always resided in Alberta, Canada, using commercially available immunodiagnostic tests. Methods: Samples from 116 healthy horses were obtained from a biobank containing horse serum collected across Alberta in 2021 and 2022. Samples were selected based on owner survey responses, ...
Bruneel E, Hermange T, Casamatta JM, Pereira A, Pimenta J, Caseiro AR.Immune-mediated keratitis (IMMK) is a chronic inflammatory corneal disease in horses. Long-term topical therapy with cyclosporine is often impractical, highlighting the need for sustained-release alternatives. Objective: To assess clinical response, tolerability, and duration of effect of episcleral silicone matrix cyclosporine implants (ESMC) in horses with presumed IMMK. Methods: Medical records of 12 horses (14 eyes) treated between 2019 and 2023 were retrospectively reviewed. IMMK subtypes were classified as epithelial (n = 3 eyes), anterior stromal (n = 9), or mid-stromal (n =...
Naveed A, Eertink LG, Soni S, Kennedy MA, Adam E, Wang D, Li F.Equine rotavirus A (ERVA) poses a significant threat to foal health, necessitating reliable serological tools for assessing protective immune responses. This study focused on the development of an enzyme-linked immunosorbent assay (ELISA) for the measurement of antibodies against the VP8∗ receptor binding core domain of ERVA. Following the expression and purification of VP8∗ receptor binding domain from the bacterial expression system, the ELISA for detecting anti-ERVA VP8∗ antibodies with VP8∗ as a coating antigen was developed and its performance was validated by the comparative anal...
Horikawa T, Maekawa N, Okagawa T, Tiyamanee W, Ganbaatar O, Nakamura H, Ikehata M, Inoue M, Nakanishi T, Tachibana T, Kato Y, Yamamoto K, Suzuki Y....Horses develop spontaneous tumors, typically in old age. Although local tumor control can be achieved using conventional therapies, systemic therapies are required to treat recurrent and/or metastatic tumors. Immune checkpoint inhibitors, such as anti-PD-L1 antibodies, have been approved for the treatment of various tumor types in humans; however, little is known about the immunosuppressive roles of the PD-1/PD-L1 pathway in horses, and the therapeutic potential of these inhibitors remains to be elucidated. Previously, we reported that the rat monoclonal anti-PD-L1 antibody 6C11-3A11 cross-rea...
Soni S, Eertink LG, Shuisong N, Loynachan A, Barnum SM, Adam EN, Kennedy MA, Wang D, Li F.Rotaviral diarrhea in foals is caused by two dominant G3P[12] and G14P[12] genotypes of equine rotavirus A (ERVA). Protection of foals against ERVA infection and disease is achievable by passive antibody transfer through colostrum from mares receiving inactivated monovalent G3P[12] vaccine. Simian rotavirus SA11 G3P[2] is also included in ERVA vaccines to protect foals. Here, we characterized cross-neutralization and protection among three distinctive rotaviruses carrying the same or different G (defined by VP7) or P (defined by VP4) genotype by using a rabbit and equine monospecific antisera ...
Sancler-Silva YFR, Costa LML, Freitas MS, Teixeira CS, Albino MV, García HDM, Fiala-Rechsteiner SMDE, Schultz ÉB, da Fonseca LA, Catalán J.The limited fertility of jennies inseminated with frozen donkey semen remains a major challenge for donkey reproduction and conservation, contrasting with the more favorable outcomes observed in mares. Species-specific differences in post-breeding uterine inflammation have been proposed as a key factor underlying this disparity. This study compared the uterine inflammatory response and pregnancy outcomes of jennies and mares inseminated with frozen donkey semen. Twelve jennies and eleven mares were monitored over 48 and 44 estrous cycles, respectively. Artificial insemination (AI) was performe...
Kapadia CL, Crook RA, Coleman S, Unger G, Douglas RH, Fedorka CE.Altrenogest is commonly used in equine veterinary medicine for the control of estrus, behavioral modifications, and maintenance of pregnancy. Recent studies have found that altrenogest may impact aspects of the immune system, including altering cytokine production in circulation and within the reproductive tract. Therefore, we hypothesize that this alteration may lead to a deviated immune response to vaccination. Sixteen mares were divided into two groups, with ten mares (n = 10) receiving long-acting injectable altrenogest (100 mg/mL; IM) administered every 10 days, and six mares (n =...
Tehrani AH, Toth K, Osinchuk N, Dufour A, Krawetz R, Sen A, Sparks H.Adult bone marrow-derived mesenchymal stromal cells (BM-MSCs) hold significant therapeutic potential in human and veterinary medicine. Traditionally, BM-MSC cultures use fetal bovine serum (FBS) to promote growth, but this practice introduces batch variability and xenogeneic contamination that complicate clinical translation. While serum-free medium (SFM) alternatives have been optimized for human MSCs, limited options have been explored for alternative or veterinary species. Here, we compared a chemically defined, customizable SFM formulation with conventional serum-containing medium (SCM) fo...
O'Brien K, Mair T, Mudhar HS, Pesavento P, Miller H, Priestnall SL, Suárez-Bonnet A.Equine squamous cell carcinomas (eSCCs) are common, and a proportion are likely induced by papillomavirus 2 (EcPV-2). Accurate prediction of clinical outcomes is challenging with no recognized prognostic criteria or consistent histopathological classification scheme for eSCC. The aims of this study were to histopathologically subtype a large case series of eSCCs (genital and ocular) and correlate them with p16 and HER-2 expression, equine papillomavirus infection status, and various clinical and histopathological parameters to predict tumour behavior and prognosis. One hundred and eighty-five...
Błaszczak A, Olczak K, Stefaniuk-Szmukier M, Tomczyk-Wrona I, Musiał AD, Grzegorczyk J, Długosz B, Szmatoła T, Ropka-Molik K.Insect bite hypersensitivity (IBH) is a prevalent allergic skin disease in horses that significantly affects animal welfare and shows evidence of genetic predisposition. Objective: Understanding the genetic basis of IBH can improve management and breeding strategies. The Equine80K BeadChip microarray was used to identify genomic regions associated with the occurrence of IBH in Hucul horses. Methods: Hair samples were collected from 127 Hucul horses, including both affected individuals and controls. DNA was extracted and genotyped. A genome-wide association study (GWAS) was performed to identif...
An T, Dugarjaviin M.(1) Background: The "Bider marking" on the shoulder of the Dun Mongolian horse represents a unique pigmentation pattern, the molecular formation mechanism of which remains incompletely understood. This study investigates the differential expression and protein localization of pigment-related genes-specifically the core transcription factor , as well as , , and -in the skin. The analysis focuses on three distinct regions: the dark-colored area of the 'Bider marking' shoulder (BIDC), the light-colored area of the 'Bider marking' shoulder (BILC), and the non-Bider-marked shoulder area (NBIS). The...
Boozarjomehri Amnieh S, Ropka-Molik K.The horse is a distinctive translational model for bridging mechanistic discovery and clinically relevant investigation because of its physiological complexity, long lifespan, athletic phenotype, and broad spectrum of naturally occurring conditions that parallel aspects of human health and disease. Its utility extends from musculoskeletal and joint research to immunology, metabolic disorders, and exercise physiology, particularly where naturally developed disease, clinically applicable imaging, and longitudinal sampling are required. Additionally, it offers opportunities to examine both chroni...
Ribeiro MG, Barbosa AN, Pereira JG, Possebon FS, Pinto JPAN, Portilho FVR, Bello TS, Paz PJL, Arabe Filho MF, Panegossi LC, Reznik AU, Zeferino LO....Rhodococcus equi, a versatile and adapted opportunistic in nature bacterium, infects animals and humans. This soil-borne microorganism widely occurs in farms. Its dissemination occurs by feces from domestic animals (particularly horses, cattle, and pigs). In the last decades, bacterial virulence has been strongly attributed to plasmid-encoded virulence-associated proteins (VAPs). To date, three virulence plasmid types have been recognized: pVAPA, pVAPB, and pVAPN, which are considered host- or livestock-adapted. The pVAPA type is related to equine isolates (horse-type), the pVAPB type is assoc...
Pfannkuche H, Maus J, Engel KM, Schiller J, Schneider MR.Skin sebaceous glands (SGs) synthesize and secrete sebum, a mixture of lipids and cellular debris that defends the external body surface against physicochemical challenges. Recent data define the SG as a dynamic entity with potential functions beyond skin protection, including immunomodulatory actions and the regulation of energy metabolism. We postulate that the SG also has important, unrecognized roles in physiological and pathological processes in domestic animals. Conversely, data derived from domestic animals may have translational relevance for humans. This review article summarizes SG s...
Connor RJ, Kawaoka Y, Webster RG, Paulson JC.The receptor specificity of 56 H2 and H3 influenza virus isolates from various animal species has been determined to test the relevance of receptor specificity to the ecology of influenza virus. The results show that the receptor specificity of both H2 and H3 isolates evaluated for sialic acid linkage specificity and inhibition of hemagglutination by horse serum correlates with the species of origin, as postulated earlier for H3 strains based on a limited survey of five human, three avian, and one equine strain. Elucidation of the amino acid sequence of several human H2 receptor variants and a...
Suzuki Y, Ito T, Suzuki T, Holland RE, Chambers TM, Kiso M, Ishida H, Kawaoka Y.The distribution of sialic acid (SA) species varies among animal species, but the biological role of this variation is largely unknown. Influenza viruses differ in their ability to recognize SA-galactose (Gal) linkages, depending on the animal hosts from which they are isolated. For example, human viruses preferentially recognize SA linked to Gal by the alpha2,6(SAalpha2,6Gal) linkage, while equine viruses favor SAalpha2,3Gal. However, whether a difference in relative abundance of specific SA species (N-acetylneuraminic acid [NeuAc] and N-glycolylneuraminic acid [NeuGc]) among different animal...
Majorek KA, Porebski PJ, Dayal A, Zimmerman MD, Jablonska K, Stewart AJ, Chruszcz M, Minor W.Serum albumin (SA) is the most abundant plasma protein in mammals. SA is a multifunctional protein with extraordinary ligand binding capacity, making it a transporter molecule for a diverse range of metabolites, drugs, nutrients, metals and other molecules. Due to its ligand binding properties, albumins have wide clinical, pharmaceutical, and biochemical applications. Albumins are also allergenic, and exhibit a high degree of cross-reactivity due to significant sequence and structure similarity of SAs from different organisms. Here we present crystal structures of albumins from cattle (BSA), h...
den Boon JA, Snijder EJ, Chirnside ED, de Vries AA, Horzinek MC, Spaan WJ.The nucleotide sequence of the genome of equine arteritis virus (EAV) was determined from a set of overlapping cDNA clones and was found to contain eight open reading frames (ORFs). ORFs 2 through 7 are expressed from six 3'-coterminal subgenomic mRNAs, which are transcribed from the 3'-terminal quarter of the viral genome. A number of these ORFs are predicted to encode structural EAV proteins. The organization and expression of the 3' part of the EAV genome are remarkably similar to those of coronaviruses and toroviruses. The 5'-terminal three-quarters of the genome contain the putative EAV p...
Lykkesfeldt J, Svendsen O.Important infectious diseases in farm animals, such as pneumonia and enteritis, are thought to be associated with the so-called oxidative stress, i.e. a chemical phenomenon involving an imbalance in the redox status of the individual animal. The specifics of oxidative stress and how it may result in disease or be prevented are complex questions with no simple answers. However, the considerable literature on the subject suggests that many researchers consider oxidative stress-related mechanisms to be important early events in disease development. A particularly intriguing aspect is that, at lea...
Prescott JF.Recent isolations of Rhodococcus equi from cavitatory pulmonary disease in patients with AIDS have aroused interest among medical microbiologists in this unusual organism. Earlier isolations from humans had also been in immunosuppressed patients following hemolymphatic tumors or renal transplantation. This organism has been recognized for many years as a cause of a serious pyogranulomatous pneumonia of young foals and is occasionally isolated from granulomatous lesions in several other species, in some cases following immunosuppression. The last decade has seen many advances in understanding o...
Couëtil LL, Cardwell JM, Gerber V, Lavoie JP, Léguillette R, Richard EA.The purpose of this manuscript is to revise and update the previous consensus statement on inflammatory airway disease (IAD) in horses. Since 2007, a large number of scientific articles have been published on the topic and these new findings have led to a significant evolution of our understanding of IAD.
Quinlivan M, Zamarin D, García-Sastre A, Cullinane A, Chambers T, Palese P.Equine influenza is a common disease of the horse, causing significant morbidity worldwide. Here we describe the establishment of a plasmid-based reverse genetics system for equine influenza virus. Utilizing this system, we generated three mutant viruses encoding carboxy-terminally truncated NS1 proteins. We have previously shown that a recombinant human influenza virus lacking the NS1 gene (delNS1) could only replicate in interferon (IFN)-incompetent systems, suggesting that the NS1 protein is responsible for IFN antagonist activity. Contrary to previous findings with human influenza virus, w...
Pawelek KA, Huynh GT, Quinlivan M, Cullinane A, Rong L, Perelson AS.Influenza virus infection remains a public health problem worldwide. The mechanisms underlying viral control during an uncomplicated influenza virus infection are not fully understood. Here, we developed a mathematical model including both innate and adaptive immune responses to study the within-host dynamics of equine influenza virus infection in horses. By comparing modeling predictions with both interferon and viral kinetic data, we examined the relative roles of target cell availability, and innate and adaptive immune responses in controlling the virus. Our results show that the rapid and ...
Puffer BA, Parent LJ, Wills JW, Montelaro RC.We have previously demonstrated that the Gag p9 protein of equine infectious anemia virus (EIAV) is functionally homologous with Rous sarcoma virus (RSV) p2b and human immunodeficiency virus type 1 (HIV-1) p6 in providing a critical late assembly function in RSV Gag-mediated budding from transfected COS-1 cells (L. J. Parent et al., J. Virol. 69:5455-5460, 1995). In light of the absence of amino acid sequence homology between EIAV p9 and the functional homologs of RSV and HIV-1, we have now designed an EIAV Gag-mediated budding assay to define the late assembly (L) domain peptide sequences con...
Woldehiwet Z.Anaplasma phagocytophilum is the recently designated name replacing three species of granulocytic bacteria, Ehrlichia phagocytophila, Ehrlichia equi and the agent of human granulocytic ehrlichiosis, after the recent reorganization of the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales. Tick-borne fever (TBF), which is caused by the prototype of A. phagocytophilum, was first described in 1932 in Scotland. A similar disease caused by a related granulocytic agent was first described in horses in the USA in 1969; this was followed by the description of two distinct granulocy...
Burbelo PD, Dubovi EJ, Simmonds P, Medina JL, Henriquez JA, Mishra N, Wagner J, Tokarz R, Cullen JM, Iadarola MJ, Rice CM, Lipkin WI, Kapoor A.Genetic and biological characterization of new hepaciviruses infecting animals contributes to our understanding of the ultimate origins of hepatitis C virus (HCV) infection in humans and dramatically enhances our ability to study its pathogenesis using tractable animal models. Animal homologs of HCV include a recently discovered canine hepacivirus (CHV) and GB virus B (GBV-B), both viruses with largely undetermined natural host ranges. Here we used a versatile serology-based approach to determine the natural host of the only known nonprimate hepacivirus (NPHV), CHV, which is also the closest p...
Jahrling PB, Geisbert TW, Geisbert JB, Swearengen JR, Bray M, Jaax NK, Huggins JW, LeDuc JW, Peters CJ.A passive immunization strategy for treating Ebola virus infections was evaluated using BALB/ c mice, strain 13 guinea pigs, and cynomolgus monkeys. Guinea pigs were completely protected by injection of hyperimmune equine IgG when treatment was initiated early but not after viremia had developed. In contrast, mice were incompletely protected even when treatment was initiated on day 0, the day of virus inoculation. In monkeys treated with one dose of IgG on day 0, onset of illness and viremia was delayed, but all treated animals died. A second dose of IgG on day 5 had no additional beneficial e...
Hiemstra PS, Maassen RJ, Stolk J, Heinzel-Wieland R, Steffens GJ, Dijkman JH.Antileukoprotease (ALP), or secretory leukocyte proteinase inhibitor, is an endogenous inhibitor of serine proteinases that is present in various external secretions. ALP, one of the major inhibitors of serine proteinases present in the human lung, is a potent reversible inhibitor of elastase and, to a lesser extent, of cathepsin G. In equine neutrophils, an antimicrobial polypeptide that has some of the characteristics of ALP has been identified (M. A. Couto, S. S. L. Harwig, J. S. Cullor, J. P. Hughes, and R. I. Lehrer, Infect. Immun. 60:5042-5047, 1992). This report, together with the catio...
MacDonald GH, Johnston RE.The initial steps of Venezuelan equine encephalitis virus (VEE) spread from inoculation in the skin to the draining lymph node have been characterized. By using green fluorescent protein and immunocytochemistry, dendritic cells in the draining lymph node were determined to be the primary target of VEE infection in the first 48 h following inoculation. VEE viral replicon particles, which can undergo only one round of infection, identified Langerhans cells to be the initial set of cells infected by VEE directly following inoculation. These cells are resident dendritic cells in the skin, which mi...
de Vries AA, Chirnside ED, Horzinek MC, Rottier PJ.We have recently shown that the genome of equine arteritis virus (EAV) contains seven open reading frames (ORFs). We now present data on the structural proteins of EAV and the assignment of their respective genes. Virions are composed of a 14-kDa nucleocapsid protein (N) and three membrane proteins designated M, GS, and GL. M is an unglycosylated protein of 16 kDa, and GS and GL are N-glycosylated proteins of 25 and 30 to 42 kDa, respectively. The broad size distribution of GL results from heterogeneous N-acetyllactosamine addition since it is susceptible to digestion by endo-beta-galactosidas...
Pallister J, Middleton D, Wang LF, Klein R, Haining J, Robinson R, Yamada M, White J, Payne J, Feng YR, Chan YP, Broder CC.The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are two deadly zoonotic viruses for which no vaccines or therapeutics have yet been approved for human or livestock use. In 14 outbreaks since 1994 HeV has been responsible for multiple fatalities in horses and humans, with all known human infections resulting from close contact with infected horses. A vaccine that prevents virus shedding in infected horses could interrupt the chain of transmission to humans and therefore prevent HeV disease in both. Here we characterise HeV infection in a ferret model and show that it closely mirror...
van Kasteren PB, Bailey-Elkin BA, James TW, Ninaber DK, Beugeling C, Khajehpour M, Snijder EJ, Mark BL, Kikkert M.Protein ubiquitination regulates important innate immune responses. The discovery of viruses encoding deubiquitinating enzymes (DUBs) suggests they remove ubiquitin to evade ubiquitin-dependent antiviral responses; however, this has never been conclusively demonstrated in virus-infected cells. Arteriviruses are economically important positive-stranded RNA viruses that encode an ovarian tumor (OTU) domain DUB known as papain-like protease 2 (PLP2). This enzyme is essential for arterivirus replication by cleaving a site within the viral replicase polyproteins and also removes ubiquitin from cell...
Hauck SM, Dietter J, Kramer RL, Hofmaier F, Zipplies JK, Amann B, Feuchtinger A, Deeg CA, Ueffing M.Autoimmune uveitis is a blinding disease presenting with autoantibodies against eye-specific proteins as well as autoagressive T cells invading and attacking the immune-privileged target tissue retina. The molecular events enabling T cells to invade and attack the tissue have remained elusive. Changes in membrane protein expression patterns between diseased and healthy stages are especially interesting because initiating events of disease will most likely occur at membranes. Since disease progression is accompanied with a break-down of the blood-retinal barrier, serum-derived proteins mask the...
Patel JR, Heldens J.This review concentrates on the epidemiology, latency and pathogenesis of, and the approaches taken to control infection of horses by equine herpesvirus types 1 (EHV-1) and 4 (EHV-4). Although both viruses may cause febrile rhinopneumonitis, EHV-1 is the main cause of abortions, paresis and neonatal foal deaths. The lesion central to these three conditions is necrotising vasculitis and thrombosis resulting from lytic infection of endothelial cells lining blood capillaries. The initiation of infection in these lesions is likely to be by reactivated EHV-1 from latently infected leukocytes. Howev...
Timoney JF.Streptococci pathogenic for the horse include S. equi (S. equi subsp. equi), S. zooepidemicus (S. equi subsp. zooepidemicus), S. dysgalactiae subsp. equisimilis and S. pneumoniae capsule Type III. S. equi is a clonal descendent or biovar of an ancestral S. zooepidemicus strain with which it shares greater than 98% DNA homology and therefore expresses many of the same proteins and virulence factors. Rapid progress has been made in identification of virulence factors and proteins uniquely expressed by S. equi. Most of these are expressed either on the bacterial surface or are secreted. Notable e...
Guy JS, Breslin JJ, Breuhaus B, Vivrette S, Smith LG.A coronavirus was isolated from feces of a diarrheic foal and serially propagated in human rectal adenocarcinoma (HRT-18) cells. Antigenic and genomic characterizations of the virus (isolate NC99) were based on serological comparison with other avian and mammalian coronaviruses and sequence analysis of the nucleocapsid (N) protein gene. Indirect fluorescent-antibody assay procedures and virus neutralization assays demonstrated a close antigenic relationship with bovine coronavirus (BCV) and porcine hemagglutinating encephalomyelitis virus (mammalian group 2 coronaviruses). Using previously des...
Snijder EJ, Wassenaar AL, Spaan WJ.To study the proteolytic processing of the equine arteritis virus (EAV) replicase open reading frame 1a (ORF1a) protein, specific antisera were raised in rabbits, with six synthetic peptides and a bacterial fusion protein as antigens. The processing of the EAV ORF1a product in infected cells was analyzed with Western blot (immunoblot) and immunoprecipitation techniques. Additional information was obtained from transient expression of ORF1a cDNA constructs. The 187-kDa ORF1a protein was found to be subject to at least five proteolytic cleavages. The processing scheme, which covers the entire OR...
Rogers GN, Pritchett TJ, Lane JL, Paulson JC.Human and animal (avian and equine) influenza A virus isolates of the H3 serotype exhibit marked differences in their ability to bind specific sialyloligosaccharide sequences that serve as cell surface receptor determinants (G. Rogers and J. Paulson, 1983, Virology 127, 361-373). Whereas human isolates of this subtype strongly agglutinate enzymatically modified human erythrocytes containing the terminal SA alpha 2,6Gal sequence, avian and equine isolates preferentially agglutinate erythrocytes bearing the SA alpha 2, 3Gal sequence. As shown in this report, a glycoprotein found in horse serum, ...
Dutkiewicz J, Mackiewicz B, Kinga Lemieszek M, Golec M, Milanowski J.Pantoea agglomerans, a bacterium associated with plants, is not an obligate infectious agent in humans. However, it could be a cause of opportunistic human infections, mostly by wound infection with plant material, or as a hospital-acquired infection, mostly in immunocompromised individuals. Wound infection with P. agglomerans usually follow piercing or laceration of skin with a plant thorn, wooden splinter or other plant material and subsequent inoculation of the plant-residing bacteria, mostly during performing of agricultural occupations and gardening, or children playing. Septic arthritis ...
Garmashova N, Atasheva S, Kang W, Weaver SC, Frolova E, Frolov I.The encephalitogenic New World alphaviruses, including Venezuelan (VEEV), eastern (EEEV), and western equine encephalitis viruses, constitute a continuing public health threat in the United States. They circulate in Central, South, and North America and have the ability to cause fatal disease in humans and in horses and other domestic animals. We recently demonstrated that these viruses have developed the ability to interfere with cellular transcription and use it as a means of downregulating a cellular antiviral response. The results of the present study suggest that the N-terminal, approxima...
Ewers C, Bethe A, Stamm I, Grobbel M, Kopp PA, Guerra B, Stubbe M, Doi Y, Zong Z, Kola A, Schaufler K, Semmler T, Fruth A, Wieler LH, Guenther S.To discern the relevance of ST648 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli as a putative new group of multiresistant and extraintestinal pathogenic strains in animals, its frequency, ESBL types, antimicrobial resistance patterns and virulence gene (VG) profiles should be determined and compared with ST131 strains from the same collection of strains. Methods: ESBL-producing E. coli isolates (n = 1152), consecutively sampled from predominantly dogs, cats and horses between 2008 and 2011, were assigned to a phylogenetic group by PCR. Partial multilocus sequence typing was ...
