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.
Péterfy F, Varró R, Fatrai Z, Barna I, Kiss I.Horse immune sera do not give satisfactory results in immunochemical techniques based on electrophoresis of antigens through antibody-containing agarose gel. As the majority of precipitating horse antibodies belongs to the beta globulins, they migrate in the gel during electrophoresis. After enzymatic treatment the pepsin fragments work well in all electroimmunodiffusion methods.
McGuire TC, Poppie MJ, Banks KL.Measurement of serum immunoglobulins in 46 foals less than 2 weeks old revealed 9 foals with hypogammaglobulinemia. The hypogammaglobulinemia was attributed to failure in transfer of immunoglobulins from dam to foal via colostrum. Three of the affected foals did not nurse at all, or only slightly, and 2 of these died of infections within a few days after birth, whereas the 3rd foal did not grow as well as normal foals. Six of the affected foals nursed in an apparently normal manner, and 5 of these had nonfatal respiratory infections between 2 and 5 weeks of age. Analysis of serum samples from ...
Chua MM, Morgan DO, Karush F.The immune response to a bacterial vaccine of Streptococcus faecalis (strain N) was characterized in all of the seven horses studied by the sustained production of about 90% IgM anti-lactose antibody over a period of 44 weeks with maximum values of the total antibody ranging from 4 mg/ml of serum to 12 mg/ml of serum. With respect to the binding of a lactose-containing ligand the association constants of the antibodies purified from sera obtained between 5 and 44 weeks fell in the range of 1 times 10-5 M-1 to 2 times 10-5 M-1. Not only was there no significant indication of maturation of a-fin...
Fontaine M, Fontaine M.In the first part of this paper the conditions for a specific titration of antibodies against the neuraminidase (N) of each of the two horse virus subtypes are defined. The antigens used are: the H72Neq 1 recombining agent to measure the anti Neq1 antibodies and the A/Duck/Ukraine/63 strain for the anti Neq2 antibodies. The immunity response to neuraminidase appears after the natural disease; this response is studied in two foci, one due to a virus belonging to the A equi I subtype (Loire 73 strain), the other to a virus of the A equi 2 subtype (SHN 73 strain). The kinetics of apparition of an...
Milgrom F, Loza U, Kano K.Double diffusion tests in gel were employed for studies of reactions between infectious mononucleosis sera and extracts of bovine, sheep and equine erythrocyte stromata. The extracts were obtained by ultrasonication of stromata prepared from trypsin-digested erythrocytes. The reaction with bovine stroma extract was composed, in many instances, of two lines. A single line was observed in reactions with sheep and equine stroma extracts. This line merged into a reaction of partial or complete identy with one of the lines formed with bovine stroma extract. Evidence was obtained that some infectioo...
Oeding P, Hájek V, Marsálek E.Out of 70 S. aurew strains isolated from the anterior nares of horses, 48 (69 per cent)
belonged to the E biotype. Approximately one third of these isolates were typed with factor
sera, the 6 (35 per cent) that were typable showing 5 different patterns. All strains but one
were non-typable with the basic sets of phages for typing human and bovine staphylococci
even at RTD x 100. Without any exception the equine staphylococci of the E biotype
contained polysaccharide Aa. Sixteen biochemically different strains belonged to the biotype A, B or C. A number of different serological patterns an...
Nakajima H, Yoshino T, Ushimi C.Equine infectious anemia virus was purified from infected horse serum samples. Electron microscope observation on negatively stained preparations of purified virus showed roughly spherical particles sized between 100 and 200 nm in diameter. In disrupted particles, an envelope was visible but no internal structure could be resolved. Since the purified virus fraction had a strong antigenic activity to antiserum in immunodiffusion reaction, these particles are thought to be the causative virus of equine infectious anemia.
Williams MR.Rats were injected intradermally with rabbit anti-ovalbumin serum and 3 hours later were challenged intravenously with ovalbumin and Evans Blue dye. Inflammatory lesions were produced within 20 minutes and their size was markedly dose-dependent. Attempts were made to interfere with this passive cutaneous anaphylaxis (PCA) by admixture of normal IgG with the rabbit anti-ovalbumin to measure the relative tissue binding affinities of IgG from various species. It was found that normal IgG from any of the species tested had an enhancing effect on PCA in rats. These immunoglobulins serially arranged...
Tabel H, Charlton KM.A horse showing clinical signs of a neurological disorder was killed and various diagnostic tests for rabies were carried out. Histopathlogy revealed a nonsuppurative encephalitis. Fluorescent antibody test and mouse inoculation test were negative. A positive diagnosis of rabies was based on a high antibody titer (1:10,000) to rabies virus in brain tissue.
Woolcock JB.A cell wall component of Streptococcus equi analogous to the M protein of group A streptococci has been identified and purified. A highly purified product has been obtained from cells by hot acid extraction, followed by acid precipitation, ammonium sulfate fractionation, and column chromatography. This product reacts with S. equi antiserum. The existence of this fraction in S. equi has been confirmed by the failure of trypsin-treated cells and their extracts to remove the long-chaining capacity of S. equi antiserum. The antigenicity of this M-like protein when incorporated in adjuvant has been...
Diethelm AG, Aldrete JS, Shaw JF, Cobbs CG, Hartley MW, Sterling WA, Morgan JM.Equine antithymocyte globulin combined with azathioprine and prednisone as immunosuppressive therapy in 50 transplant recipients prolonged allograft survival and seemed to modify the severity of rejection episodes. Although nine patients died from a variety of causes, only three kidneys were lost to rejection, one of which was hyperacute. There were no serious untoward hematologic or systemic effects caused by the ATG, and all patients completed the course of therapy. Infection, a serious and frequent complication of transplant patients, was encountered no more often than in other transplant s...
Matthews AG.This paper overviews some recent developments in mammalian corneal immunobiology, and discusses how these may act as pointers towards understanding the immunology underlying some common corneal diseases in the horse, including infectious ulceration and presumptively immune-mediated non-ulcerative disease. Specifically, three aspects of corneal immunobiology are examined: the role of Toll-like receptors in surface immunity and in the etiogenesis of microbial ulceration, the relationship between conjunctiva associated lymphoid tissue (CALT) and immunoprotection of the corneal surface, and the me...
Blancquaert AB, Colgan SP, Bruyninckx WJ.To identify the influence of technical factors on the in vitro motility of equine neutrophils towards streptococcus culture supernatant in an under-agarose assay, we studied the changes in eight cell migration parameters. The distances the phagocytes travelled by directed, random and spontaneous migration increased with incubation time, cell concentration and the gelatin and serum contents of the migration plates. The contribution of chemotaxis to the phagocyte migrations, however, decreased simultaneously. The directed and random, though not the spontaneous, migrations of the phagocytes incre...
Jennings SH, Wise AG, Nickeleit V, Maes RK, Cianciolo RE, Del Piero F, Law JM, Kim Y, McCalla AC, Breuhaus BA, Roberts MC, Linder KE.Polyomaviruses produce latent and asymptomatic infections in many species, but productive and lytic infections are rare. In immunocompromised humans, polyomaviruses can cause tubulointerstitial nephritis, demyelination, or meningoencephalitis in the central nervous system and interstitial pneumonia. This report describes 2 Standardbred horses with tubular necrosis and tubulointerstitial nephritis associated with productive equine polyomavirus infection that resembles BK polyomavirus nephropathy in immunocompromised humans.
Keller C, Schulz R.To determine the full-length complementary DNA (cDNA) sequence of equine retinal and pineal gland phosducin (PHD) and to clone these sequences. Methods: Samples of equine retinal RNA. Methods: A primer set was designed for use in identifying a fragment of the equine PHD nucleotide sequence, derived from retinal RNA samples, and subsequently for use to deduce specific primers for additional examination. The full-length cDNA was determined by the method of rapid amplification of cDNA ends (RACE). For full-length cDNA, newly designed primers were used. Nucleotide sequences were analyzed by use of...
Giguère S, Prescott JF.The remarkable ability of the horse and other animals to prevent infection by most bacterial pathogens encountered is the result of a complex set of distinct but overlapping defense mechanisms. This article summarizes the current state of knowledge on innate and adaptive immunity to bacterial pathogens and reviews various ways in which some bacteria have evolved in order to evade components of the host response.
Rosendal S, Blackwell TE, Lumsden JH, Physick-Sheard PW, Viel L, Watson S, Woods P.Mycoplasma felis has been isolated from horses with pleuritis, and limited research indicates that mycoplasma pleuritis can be reproduced in horses. The serodiagnostic potential of the indirect hemagglutination and the metabolism-inhibition tests was evaluated by testing 177 horses for antibodies to M felis. Seven horses with M felis pleuritis developed antibodies, and 6 horses with sterile or bacterial pleuritis had high titers suggesting a previous M felis infection. Six horses with pleuritis (one sterile and five bacterial) had low or no titers to M felis. Only one of 30 horses with conditi...
Mugg PA, Hill A.The failure of N. gonorrhoeae to grow on isolation media was found to be due to inhibitory substances present in commercially available horse sera. Subsequent investigations indicated that the inhibitory action of the horse serum may have been due to antibodies to N. gonorrhoeae, H. influenzae, H. parainfluenzae and beta hemolytic streptococci. This experience highlights the need for media quality control programmes in laboratories which prepare microbiological culture media.
Kumar S, Yokoyama N, Kim JY, Bork-Mimm S, Inoue N, Xuan X, Igarashi I, Sugimoto C.Theileria equi is a tick-transmitted intraerythrocytic protozoan parasite in equids. Equine merozoite antigen (EMA)-1 and EMA-2 of T. equi have been identified as immunodominant proteins co-expressed on the surface of extra-erythrocytic merozoites. Additionally, only the EMA-2 is shed into the cytoplasm of infected erythrocyte or inside the erythrocytic membrane during their early developmental stage. In this study, we initially performed West-Western blot analysis on Triton X-100-insoluble erythrocytic skeleton collected from a healthy horse, using a glutathione S-transferase (GST)-tagged rec...
Liau MY, Huang RJ, Chen SW.As the conventional hyperimmunization schedule in horses introduced by Tanaka could not produce enough neutralizing antibody against Naja naja atra venom, the mixture of Carboxymethyl cellulose (CMC)-Cobra venom incorporated with adjuvant was used for immunization. The neutralizing antibody produced (30 LD50) seemed to be increased but still not to reach the satisfactory level. By using CMC-Cobratoxin adjuvant mixture as an immunizing agent, highly potent antivenin (220 LD50) was obtained.