Topic:Antibodies
Antibodies in horses are specialized proteins produced by the immune system in response to foreign substances, known as antigens. These substances can include pathogens such as bacteria, viruses, and parasites. Antibodies function by recognizing and binding to specific antigens, thereby neutralizing them or marking them for destruction by other immune cells. In equine health, antibodies are integral to both natural immune responses and those induced by vaccinations. The study of antibodies in horses encompasses their production, diversity, and role in disease resistance and management. This page gathers peer-reviewed research studies and scholarly articles that explore the generation, function, and implications of antibodies in equine immunology and disease control.
Equine Influenza Virus and Vaccines. Equine influenza virus (EIV) is a constantly evolving viral pathogen that is responsible for yearly outbreaks of respiratory disease in horses termed equine influenza (EI). There is currently no evidence of circulation of the original H7N7 strain of EIV worldwide; however, the EIV H3N8 strain, which was first isolated in the early 1960s, remains a major threat to most of the world's horse populations. It can also infect dogs. The ability of EIV to constantly accumulate mutations in its antibody-binding sites enables it to evade host protective immunity, making it a successful viral pathogen. C...
Antimicrobial Effects of Equine Platelet Lysate. The development of antimicrobial resistant bacteria and the lack of novel antibiotic strategies to combat those bacteria is an ever-present problem in both veterinary and human medicine. The goal of this study is to evaluate platelet lysate (PL) as a biological alternative antimicrobial product. Platelet lysate is an acellular platelet-derived product rich in growth factors and cytokines that is manufactured via plateletpheresis and pooled from donor horses. In the current study, we sought to define the antimicrobial properties of PL on select gram-positive and gram-negative bacteria. Results ...
Humoral Immune Response Evaluation in Horses Vaccinated with Recombinant Clostridium perfringens Toxoids Alpha and Beta for 12 Months. In horses, Clostridium perfringens is associated with acute and fatal enterocolitis, which is caused by a beta toxin (CPB), and myonecrosis, which is caused by an alpha toxin (CPA). Although the most effective way to prevent these diseases is through vaccination, specific clostridial vaccines for horses against C. perfringens are not widely available. The aim of this study was to pioneer the immunization of horses with three different concentrations (100, 200 and 400 µg) of C. perfringens recombinant alpha (rCPA) and beta (rCPB) proteins, as well as to evaluate the humoral immune response ove...
Serological Evidence of Common Equine Viral Infections in a Semi-Isolated, Unvaccinated Population of Hucul Horses. Huculs () are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal sec...
Serum Antibody Activity against Poly-N-Acetyl Glucosamine (PNAG), but Not PNAG Vaccination Status, Is Associated with Protecting Newborn Foals against Intrabronchial Infection with Rhodococcus equi. Rhodococcus equi is a prevalent cause of pneumonia in foals worldwide. Our laboratory has demonstrated that vaccination against the surface polysaccharide β-1→6-poly-N-acetylglucosamine (PNAG) protects foals against intrabronchial infection with R. equi when challenged at age 28 days. However, it is important that the efficacy of this vaccine be evaluated in foals when they are infected at an earlier age, because foals are naturally exposed to virulent R. equi in their environment from birth and because susceptibility is inversely related to age in foals. Using a randomized, blind experim...
Clinical Presentation and Laboratory Diagnostic Work-Up of a Horse with Tick-Borne Encephalitis in Switzerland. Tick-borne encephalitis is an important viral tick-borne zoonosis in Europe and Asia. The disease is induced by tick-borne encephalitis virus (TBEV). This report describes a 16-year-old Warmblood gelding presenting with sudden onset of lethargy, ataxia, and muscle fasciculations on the nostrils, the lips, and the eye lids as the most important clinical findings. The horse further had a mild facial nerve paralysis with drooping of the right upper and lower lip. Diagnosis was based on paired serum samples using TBEV-ELISAs revealing high serum IgM in the first sample with normal IgM in the secon...
Immune response of adult horses, pregnant mares and foals to an experimental vaccine with recombinant EMA-2 protein of Theileria equi. Equine theileriosis, caused by the Theileria equi protozoan, is a disease of worldwide importance. T. equi expresses surface proteins, of which the EMA-2 protein is a promising antigen for vaccine use. The aim of this study was to evaluate the immune response of adult horses, pregnant mares, and foals to an experimental EMA-2 protein of recombinant T. equi vaccine. A total of 46 horses were used in this study for vaccine trials and challenges. Twelve geldings, 14 pregnant mares, and 14 foals were divided into vaccinated and control groups. Total serum specific anti-rEMA-2 IgG, IgG subclasses, ...
Investigation of the Bi-Weekly Administration of Diclazuril on the Antibody Kinetics to Sarcocystis Neurona in Healthy Horses. The aim of this study was to determine if bi-weekly administration of diclazuril at half the label dose would reduce seroprevalence and magnitude of titers to S. neurona in healthy horses naturally exposed to the apicomplexan protozoal parasite. 12 healthy adult horses were moved from a low-risk exposure to a farm with high exposure rate to S. neurona in their horse population. The horses were randomly assigned to either a treatment or a control group. Treatment consisted in the administration of half the label dose (0.5 mg/kg) of diclazuril (Protazil) pelleted top dress twice weekly (every 3-...
PD-L1/PD-1 and CTLA-4 Expression in Equine Penile Squamous Cell Carcinomas. In horses, penile squamous cell carcinomas (epSCCs) are among the most common cutaneous neoplastic lesions. These tumors usually arise in benign lesions such as viral plaques and papillomas frequently induced by papillomavirus type 2 (EcPV2) infection. In the last decade, the introduction of immune checkpoint inhibitors (ICI) for the treatment of human cancers has demonstrated promising results. Among the most commonly targeted pathways, there is PD-1/PD-L1 and CTLA-4. The aim of this study is to investigate the expression of the PD-1/PD-L1 pathway and CTLA-4 in the tumor microenvironment of ...
Application of equine herpesvirus-1 vaccine inactivated by both formaldehyde and binary ethylenimine in equine. Equine herpesvirus-1 infection in horses causes a wide range of manifestations affecting the respiratory tract. The virus can cause serious economic losses through sporadic abortion in pregnant mares, perinatal death, respiratory disease in young foals. This study was designed to prepare inactivated equine herpesvirus-1 (EHV-1) vaccine using both 0.005 M binary ethylenimine (BEI) and 0.0006% formaldehyde (FA) to decrease the use of BEI and provide a good immunological response. The efficacy, safety, and duration of immunity of the prepared inactivated EHV-1 vaccine were evaluated. Methods: The...
A Scoping Review of West Nile Virus Seroprevalence Studies among African Equids. West Nile virus (WNV) is an emerging and re-emerging zoonotic flavivirus first identified in and endemic to Africa. The virus is transmitted between birds by biting mosquitoes, with equids and humans being incidental hosts. The majority of infected incidental hosts display no or only mild clinical signs, but a fraction develop encephalitis. The aim of this scoping review was to identify and evaluate primary research on the presence of antibodies to WNV among African equids. Three bibliographic databases and the grey literature were searched. Of 283 articles identified, only 16 satisfied all th...
Sperm-bound antisperm antibodies are associated with poor cryosurvival of stallion spermatozoa. Different stallions exhibit a high level of variation in the ability of their sperm to survive cryopreservation. A large fraction of stallions show poor post-thaw sperm motility, and their semen is not suitable for commercial freezing. In this study, we hypothesized that the presence of sperm-bound antisperm antibodies (ASAs) was associated with poor cryosurvival of stallion sperm. Our objective was to assess the level of ASA binding to stallion sperm, and determine if it was associated with good or poor sperm cryosurvival. In Experiment 1, cooled shipped semen from 27 stallions was frozen usi...
Sero-Monitoring of Horses Demonstrates the Equivac® HeV Hendra Virus Vaccine to Be Highly Effective in Inducing Neutralising Antibody Titres. Hendra virus (HeV) is a high consequence zoonotic pathogen found in Australia. The HeV vaccine was developed for use in horses and provides a One Health solution to the prevention of human disease. By protecting horses from infection, the vaccine indirectly protects humans as well, as horses are the only known source of infection for humans. The sub-unit-based vaccine, containing recombinant HeV soluble G (sG) glycoprotein, was released by Pfizer Animal Health (now Zoetis) for use in Australia at the end of 2012. The purpose of this study was to collate post-vaccination serum neutralising anti...
Sarcocystis neurona, seroprevalence of antibodies in equines and research of oocystis in opossum in Ilhéus – Itabuna microregion, Bahia, Brazil. The aims of this study were to determine the seroprevalence of Sarcocystis neurona antibodies in equines in the Ilhéus-Itabuna microregion (BA), and identify possible factors associated with infection. The presence of sporocysts/oocysts of Sarcocystis spp. was also verified in Didelphis spp. A total of 669 serum samples were collected from equines in 56 properties located in 12 municipalities in the region. Indirect fluorescent antibody test was performed with slides containing merozoites of the S. neurona, using a cut-off titer of 1:80. Occurrence of 7.92% of anti-S. neurona antibodies was o...
The Hendra virus vaccine: perceptions regarding the role of antibody titre testing. To elucidate veterinarians' and horse owners' perceptions towards the use of Hendra virus (HeV) antibody titre testing and how it influences veterinary advice. Methods: Six semi-structured phone interviews were conducted with veterinarians who have submitted samples for HeV antibody titre testing. Interviews were recorded, transcribed and thematically analysed to identify and report common themes within the data. Results: Veterinarians are predominantly using the titre tests as an alternative to vaccination due to clients' fear of vaccine reactions. The high cost of titre testing, the difficul...
West Nile Virus Seroprevalence in a Selected Donkey Population of Namibia. West Nile Virus (WNV) is a mosquito-borne virus enzootically maintained in birds. However, it can incidentally infect other species, leading to sometimes severe clinical consequences like in horses and especially human beings. Despite the topic relevance, the presence and distribution of WNV are currently unknown in Namibia. Several countries implement surveillance systems based on virus detection in birds, mosquitoes, and vertebrate species including horses. The present study aimed to fill this knowledge gap by serologically evaluating WNV exposure in Namibian donkeys, whose population is rem...
Safety, Tolerability, and Pharmacokinetics of NTM-1632, a Novel Mixture of Three Monoclonal Antibodies against Botulinum Toxin B. Botulism is a rare, life-threatening paralytic disease caused by Clostridium botulinum neurotoxin (BoNT). Available treatments, including an equine antitoxin and human immune globulin, are given postexposure and challenging to produce and administer. NTM-1632 is an equimolar mixture of 3 human IgG monoclonal antibodies, B1, B2, and B3, targeting BoNT serotype B (BoNT/B). This first-in-human study assessed the safety, tolerability, pharmacokinetics (PK), and immunogenicity of NTM-1632. This double-blind, single-center, placebo-controlled dose escalation study randomized 3 cohorts of healthy vol...
A leptin sandwich ELISA kit unusable for domestic animals. An instance of hormone assay method flaw is reported. In this journal Chronobiology International, two papers appeared in which an ELISA method for human serum or plasma was utilized for blood serum of horse and sheep, respectively. From our testing, it is resulted that such method does not work at all for equine, sheep and other animal species. The use of commercial hormone assay kits for heterologous species always needs a careful validation procedure. First, the same hormone molecule by different species could not share enough homology to be regognized by and react with antibodies utilized ...
Immunological Cross-Reactivity of Proteins Extracted from the Oomycete Pythium insidiosum and the Fungus Basidiobolus ranarum Compromises the Detection Specificity of Immunodiagnostic Assays for Pythiosis. Pythiosis, a life-threatening disease caused by , has been increasingly diagnosed worldwide. A recently developed immunochromatographic test (ICT) enables the rapid diagnosis of pythiosis. During the 3-year clinical implementation of ICT in Thailand, we collected the laboratory reports of 38 animals with suspected pythiosis and detected ICT false-positive results in three horses and a dog with basidiobolomycosis. and cause infections with indistinguishable clinical and microscopic features. This study investigated cross-reactive antibodies by probing and crude extracts and cell-free synthe...
Pathogenesis, MicroRNA-122 Gene-Regulation, and Protective Immune Responses After Acute Equine Hepacivirus Infection. 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...
Enhanced immune effects and protection conferred by simultaneously targeting GAPDH, SeM, and EAG of S. equi via TLR4. Strangles, which is caused by Streptococcus equi subspecies equi, is one of the most prevalent equine infectious diseases and poses heavy economic losses worldwide. Although various vaccines have been used for decades, they seemed to be sub-optimal to demonstrate effective protection, and the antigen component of vaccines against S. equi remains to be optimized. In the present study, three target antigens (M-like protein, α2-macroglobulin and IgG-binding protein, and glyceraldehyde-3-phosphate dehydrogenase) were selected and expressed. Mice were immunized and challenged, and their immune res...
Serosurvey for equine piroplasms in horses and donkeys from North-Western Nigeria using IFAT and ELISA. Equine piroplasmosis is caused by apicomplexan parasites, namely, and , which are transmitted to equids principally through ticks. To ascertain the exposure of equines to agents of equine piroplasms, we tested serum samples collected from horses (n = 272) and donkeys (n = 170) in North-Western Nigeria for the presence of antibodies against and using IFAT and ELISA. The seroprevalence of in the horses determined using IFAT and ELISA was 48.89% and 45.96%, respectively, while for , it was 6.3% and 0.4%, respectively. For , the seroprevalence based on IFAT and ELISA results in donkeys was...
Prophylactic Efficacy of Equine Immunoglobulin F(ab’)2 Fragments Against Feline Parvovirus. Feline parvovirus (FPV), a type of parvovirus prevalent worldwide, can cause foetal death and acute enteritis in adult cats with severe leukopenia, and yet there are no effective drugs to prevent or treat FPV. Here, the immune effects of two FPV vaccines on horses were compared. IgG was extracted from FPV-immunized horse sera. Equine F(ab') fragments were obtained from pepsin-digested IgG and then purified by protein-G column chromatography. The results showed that the inactivated FPV oil vaccine was more effective than the inactivated FPV propolis vaccine in helping healthy horses to produce ...
Serological Survey of Leptospira Infection in Arabian Horses in Poland. Leptospirosis is one of the most common zoonotic infections worldwide, including in most livestock, some companion animals, horses, wildlife, and humans. Epidemiological estimation of its prevalence in all species is difficult due to the variety of clinical presentations and challenges regarding laboratory diagnosis. The purpose of this study was to measure the seroprevalence of leptospiral infection in Arabian horses kept in the largest breeding farms in Poland, representing over 15% of the Polish Arabian horse population. Leptospira antibodies were detected by MAT (cut-off 1:100) in 33.2% of...
Decreased Virus-Neutralizing Antibodies Against Equine Herpesvirus type 1 In Nasal Secretions of Horses After 12-hour Transportation. This study evaluated the effects of 12-hour transportation on immune responses to equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4). Possible replication of EHV-1 and EHV-4 was monitored by real-time PCR of nasal swabs and peripheral blood mononuclear cells (PBMCs), and changes in systemic and mucosal antibodies were investigated. Six healthy Thoroughbreds with transport experience were transported in commercial trucks, repeating the same three-hour route four times. Blood samples for cortisol measurement were taken before departure and every three hours. Nasal swabs, PBMCs, nasal wash and ...
Seroprevalence of Theileria equi, Babesia caballi, and Trichinella spp. infections in horses and donkeys from Nigeria, West Africa. The protozoan parasites Theileria equi and Babesia caballi, transmitted by ticks, cause equine piroplasmosis, the most prevalent tick-borne disease in equids. Trichinellosis is a worldwide food-borne zoonosis caused by helminth Trichinella spp. that can lead to serious disease in humans, with fatal outcome. Although the infection is rare in horses, it deserves attention due to the increasing use of horse meat as a source of protein for humans. Horse trichinellosis is caused by several Trichinella species, most commonly by T. spiralis. The aim of the study was to determine the prevalence of ant...
Seroepidemiology of Sarcocystis neurona and Neospora spp. in horses, donkeys, and mules from Colombia. Sarcocystis neurona and Neospora spp. are related protozoa that can cause equine protozoal myeloencephalitis (EPM). The present study aimed to determine the frequency of antibodies to these parasites in 649 equids (351 horses, 267 donkeys, and 31 mules) from six departments in the North and Northwest of Colombia. For this purpose, the indirect fluorescent antibody test (IFAT) was used for detecting antibodies against S. neurona and Neospora spp. with a cut-off point of 1:20 and 1:50, respectively. A binomial logistic regression model was selected to predict variables associated with exposure. ...
Microbial Prevalence and Antimicrobial Sensitivity in Equine Endometritis in Field Conditions. Endometritis is one of the main causes of infertility in mares. In the present study, 363 mares with a history of repetitive infertility, and positive endometrial cytology and/or vaginal discharge were included. An endometrial swab for microbiological purposes plus sensitivity test was obtained from each mare. A positive culture was obtained in 89% of mares. The main isolated genera were (25.1%), (18.2%), (17.3%) and (12.1%). With regard to species, the most isolated microorganism was (17.3%), spp. (15.6%) and spp. (13.5%). Sensitivity tests showed that the most efficient antimicrobial ...
In vitro Inhibitory Activity of IgY Antibodies Against Salmonella Ser. Newport Isolated from Horses. Equine salmonellosis is caused by several Salmonella serotypes, including Salmonella Newport, which cause enterocolitis and diarrhea. Treatment usually includes the administration of antibiotics. However, since multidrug-resistant Salmonella is commonly detected, alternative options to control the pathogen are needed. One of these options is the use of specific egg yolk antibodies (IgY) for passive immunotherapy. Thus, the aim of our work was to produce IgY antibodies against an equine S. Newport strain and assess their in vitro inhibitory activity. To this end, laying hens were immunized with...
Development and characterization of two equine formulations towards SARS-CoV-2 proteins for the potential treatment of COVID-19. In the current global emergency due to SARS-CoV-2 outbreak, passive immunotherapy emerges as a promising treatment for COVID-19. Among animal-derived products, equine formulations are still the cornerstone therapy for treating envenomations due to animal bites and stings. Therefore, drawing upon decades of experience in manufacturing snake antivenom, we developed and preclinically evaluated two anti-SARS-CoV-2 polyclonal equine formulations as potential alternative therapy for COVID-19. We immunized two groups of horses with either S1 (anti-S1) or a mixture of S1, N, and SEM mosaic (anti-Mix) ...