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.
DITCHFIELD J, MACPHERSON LW.From outbreaks of upper respiratory infection of horses in the Toronto area between 1960 and 1963, several viruses have been isolated. The viruses, isolated in tissue cultures or eggs, include an equine strain of Myxovirus parainfluenzae 3; two strains of equine influenza virus, A/equi-1/Prague/56, and A/equi-2/Miami/63; equine rhinopneumonitis virus, and two newly recognized viruses of the horse, equine rhinoviruses. In addition serological evidence suggested a widespread infection with these viruses in the population under study. Because of the identical clinical picture seen and the complex...
Melnick JL, Hampil B.This paper summarizes the results of co-operative studies undertaken by the WHO International Reference Centre for Enteroviruses and a number of WHO Regional Reference Centres for viruses, WHO Virus Collaborating Laboratories, or other laboratories in a comprehensive testing programme of enterovirus equine antisera. The studies were designed to appraise the specificity of immune serum prepared in horses against five representative prototype enteroviruses (poliovirus 1, coxsackieviruses A9 and B3, and echoviruses 4 and 11). Tests for neutralizing antibody were performed not only against the hom...
ROCKEY JH, KLINMAN NR, KARUSH F.Anti-p-azophenyl-beta-lactoside (Lac) antibody has been isolated from equine antiserum by specific precipitation with Lac-HSA (human serum albumin) and Lac-Hy (hemocyanin). Antibody was separated from antigen by chromatography on DEAE cellulose and zone electrophoresis in solvents containing lactose. Six antigenically distinct immunoglobulins have been identified in purified equine anti-Lac antibody: 7S beta(2A)-globulin, 19S gamma-globulin, a 10S gamma(1) globulin, and three antigenically distinct 7S gamma-globulins. The specific hapten-binding activity of the 7S beta(2A)-antibody and of the ...
CASALS J.A study by hemagglutination-inhibition test showed that 19 strains of eastern equine encephalitis virus grouped themselves in two main types, which have been designated North American and South American. The former consists of ten strains from the eastern half of the United States, from Massachusetts to Florida; Jamaica, the Dominican Republic, and, subject to confirmation, Thailand. The South American type comprises nine strains from Panama, Trinidad, British Guiana, Brazil, and Argentina. The strains were isolated from different natural hosts over a period of 30 years.
KAMINSKI M, GAJOS E.TWENTY-THREE fresh and 28 frozen (1–11 years old) samples of horse sera, 62 frozen donkey sera (3–11 years old), 24 frozen mule sera (2–10 years old), and 1 frozen 2-year-old serum sample of a hinny (offspring of a she-ass by a stallion) were studied by starch- and agar-gel electrophoresis (starch gel: horizontal migration, discontinued buffer system; tris-citrate pH 8.7 and borate 0.3 M, pH 8.2; 2 V/cm for 14 h; 10 samples analysed simultaneously; 0.1 ml. serum mixed with soluble starch Merck; agar gel: 0.8 per cent agar in veronal buffer 0.025 M, pH 8.2; 4.5 V/cm; 2½ h; 10 samples on ...
Harman RM, Churchill KA, Jager MC, Van de Walle GR.Equid herpesvirus 1 (EHV-1) outbreaks occur when virus spreads from infected horses to in-contact horses, primarily via nasal shedding. This study evaluated the efficacy of factors secreted by equine peripheral blood derived mesenchymal stromal cells (PB-MSCs), collectively named the secretome, to inhibit the growth of EHV-1 in (i) 2D epithelial cell cultures (RK-13) in vitro, (ii) 3D equine nasal explants in vitro and (iii) an EHV-1 infection mouse model in vivo. The PB-MSC secretome was found to inhibit EHV-1 in RK-13 cells as well as in the epithelium of equine nasal explants. Although the ...
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...
Smith ML, Chapman CB.An acepromazine (ACP) hapten was synthesised, coupled to bovine serum albumin and injected into a horse to produce antibodies to the drug. A competitive ELISA was developed whereby ACP attached to the solid phase via lysozyme competed with free ACP present in phosphate buffered saline, horse serum or horse urine for limiting amounts of antibody. The assay could detect the presence of ACP and, or, some of its metabolites in horse urine for at least 25 hours after intravenous injection of 0.1 mg kg-1 ACP maleate, but because of non-specific interference, horse serum could not be used. As little ...
Magnarelli LA, Ijdo JW, Van Andel AE, Wu C, Oliver JH, Fikrig E.To test serum samples of dogs and horses by use of class-specific recombinant-based ELISA for establishing a diagnosis of granulocytic ehrlichiosis attributable to infection with organisms from the Ehrlichia phagocytophila genogroup. Methods: Serum samples from 43 client-owned dogs and 131 horses (81 with signs of acute illness and 50 without signs of disease). Methods: Serum samples were analyzed, using ELISA with a recombinant 44-kd protein antigen for IgM and IgG antibodies to the human granulocytic ehrlichiosis (HGE) agent (NCH-1 strain). Western blot analyses, using infected human promyel...
Rółkowski R, Worowski K, Skrzydlewski Z.Antiheparin activity of plasma of different species of vertebrates depends to a large extent on contents of low density lipoproteins (LDL). High antiheparin activity of the blood plasma of chicken and human corresponds to high contents of LDL and low antiheparin activity of the blood plasma of horse, cow, sheep, dog and pig corresponds to decreased contents of these proteins. Differences in the contents of fibrinogen, acid alfa1-glycoproteins, globulins, alkaline proteins and antithrombin III activity have smaller influence on antiheparin activity in the blood plasma of the examined animals.
Thompson NE, Bergdoll MS, Pattee PA.The factor in normal sera primarily responsible for the enhancement of transfection (and transformation) of Staphylococcus aureus was identified as fibronectin. Serum samples which were depleted of fibronectin by affinity chromatography showed a marked decrease in enhancing activity. Fibronectin isolated from sera of several animal species demonstrated enhancing activity.
Kettler MK, Weil MR, Mascotti K, Perryman LE.A group of diseases termed combined immunodeficiency (CID) results in a severe form of immunodeficiency. While CID in humans has two genetics bases, in Arabian it is inherited in an autosomal recessive manner. Kettler et al. (1989) determined that uric acid was significantly (p 0.05) between carrier and non-carrier horse's serum levels of hypoxanthine or xanthine. These data, combined with our previous ones suggest that an enzymatic lesion in the purine salvage pathway may occur at the urate oxidase step. ZUSAMMENFASSUNG: Serum-Hypoxanthin- und -Xanthin-Spiegel in Pferden mit Heterozygotie fÃ...
Kirisawa R, Hashimoto N, Tazaki M, Yamanaka H, Ishii R, Hagiwara K, Iwai H.cDNA generated from lipopolysaccharide-stimulated equine peripheral blood mononuclear cells was used to amplify and clone type I and type II equine interleukin-1 receptors (IL-1RI and IL-1RII) using primers derived from semi-conserved regions between human and mouse IL-1RI and IL-1RII sequences, respectively. 5' and 3' terminal sequences of equine IL-1RI and IL-1RII were amplified by 5' and 3' rapid amplification of cDNA ends. The deduced amino acid sequence of equine IL-1RI demonstrated 77, 64 and 63% similarity with human, mouse and rat sequences, respectively. The predicted amino acid seque...
Wells M, Gaffin SL.Passive immunotherapy with anti-lipopolysaccharide hyperimmune equine plasma (Anti-LPS) is effective in treating experimental Gram-negative bacterial infections. The bactericidal activity of anti-LPS towards five different Pseudomonas species, including two multiresistant Pseudomonas aeruginosa isolates was tested here, as well as the ability of anti-LPS to inhibit the quantitative chromogenic limulus amoebocyte lysate (LAL) assay. Anti-LPS caused a mean reduction of 84.4 +/- 3.2% (P less than 0.001) in the number of colony forming units (cfu) of all isolates, whereas saline and complement ina...
McFarlane JR, Coulson SA, Papkoff H.This study describes the presence of immunoactive and bioactive eCG-like material in full-term placentas of both domestic horses and zebras. Term placental extracts were immunoreactive in an LH monoclonal antibody RIA, and methods successfully used previously for the purification of eCG and eLH were employed to further concentrate the immunoreactive materials to the point where additional characterization studies could be performed. Sufficient equine material was obtained to perform a final fractionation on a concanavalin A Sepharose column yielding an unadsorbed fraction, e17A, and an adsorbe...
Metenier L, Grosclaude J, Meriaux JC.The chief application of blood typing in domestic animals is in the verification of parentage. However, the acquisition of good standardized reagents in sufficient quantity remains an obstacle for the development of this work. The production of monoclonal antibodies directed against blood group determinants offers an attractive means of improving both the quality and quantity of serological reagents, and could facilitate the definition of new specificities. Fusions between a mouse myeloma line and splenocytes from mice immunized with horse red cells have resulted in four hybridomas producing a...
Shivers CA, Liu IK.Sera and follicular fluid from mares previously determined as having antibodies to the zona pellucida were exposed to porcine ovarian oocytes before insemination with boar spermatozoa in vitro. There was a dramatic decline in the number of spermatozoa bound to zonae compared to treatments with sera and follicular fluid from mares negative for zona antibodies. These data suggest that antibodies reactive with the zona pellucida may be responsible for reduced or even complete infertility in some mares. In a group of 50 randomly selected mares tested for antizona antibodies, 2 pregnant mares were ...
Eichhorn W.Infections and clinical diseases caused by equine 2 influenza A viruses are observed worldwide. The frequency of these outbreaks supports the hypothesis that antigenic variation of the surface proteins may play an important role. For the demonstration of these variations, monoclonal antibodies (Mabs) were prepared. They are directed against the hemagglutinin or the neuraminidase of the prototype strain a/eq/Miami/1/63. In hemagglutination-inhibition assays with Mabs two reaction patterns were observed: four Mabs inhibited 14 out of 17 strains tested. Another Mab recognized the hemagglutinin of...
Hobo S, Niwa H, Anzai T, Jones JH.In this study, to evaluate the influence of strangles vaccination on serological test results, we investigated the changes in strangles serum antibody levels in horses after vaccination and subsequent intranasal challenge with S. equi. The horses were vaccinated for strangles with either a component vaccine (Group C) or a live vaccine (Group L). We measured changes in strangles serum antibody levels weekly for 20 weeks after vaccinating horses twice for strangles over a 3-week interval, and for 7 weeks after intranasal challenge with S. equi in the same horses. Serum antibody responses to the ...
Word TA, Larsen RW.Treatment of horse heart Cytochrome-c (Cc) with N-chloro-4-toluosulfonamide (Chloramine-t, CT) results in the oxidation of methionine (Met) residues to the corresponding sulfoxide including the distal heme ligand, Met80. The resulting Fe-sulfoxide coordination is sufficiently labile in the ferrous form to be displaced by gaseous ligands, including CO. Photolysis of the CO-CT-Cc complex provides an opportunity to examine ligand binding dynamics that are associated with a relatively rigid distal heme pocket. In this work, photoacoustic calorimetry (PAC) was utilized to obtain the kinetics as wel...
Adeyefa CA, McCauley JW, Tomori O.The complete amino acid sequences of the hemagglutinin (HA) glycoprotein of three equine-2 influenza viruses from tropical Africa are presented in comparison with that of a well characterized European equine-2 virus (Suffolk/89) and a consensus sequence from the database. The sequences of the tropical African viruses were deduced from the complete nucleotide sequences of their HA genes reported earlier. Mutational changes in the nucleotide sequences resulted in amino acid changes in the HA which led to the introduction of a new asparagine-linked (N-linked) glycosylation site in two viruses. Th...
Bowling AT, Ewalt-Evans R.Family data are presented for a new allele (Aabdg) in the A system of horse erythrocyte alloantigens which includes factors Aa and Ab traditionally thought to be products of allelic genes. Evidence for incorrect assignment of the codominant factor Ae in the presence of Ab and Ac and the absence of Aa is discussed.
Dyson DA, Smith GR.When incorporated in solid medium at a concentration of 15 per cent, the defibrinated blood of certain horses strongly suppressed the growth of some, but not all, strains of Mycoplasma mycoides subsp mycoides so that many colonies failed to develop to a visible size. Blood from a single rabbit was tested and found to exert a similar effect. There was striking variation in the degree of inhibition produced by different samples of horse blood and, of five strains of the organism examined, the T1 vaccine strain was the most susceptible. The results suggested that the effect was not due to antibod...
The Journal of hygieneDecember 1, 1982
Volume 89, Issue 3 529-538 doi: 10.1017/s0022172400071102
Corbel MJ, Brewer RA.Immunoelectrophoresis of ultrasonically disrupted Haemophilus equigenitalis (contagious equine metritis organism) cells against rabbit and equine antisera disclosed at least 11 precipitating antigens. Two of these, a polysaccharide and a lipopolysaccharide-protein complex, were of high molecular weight and located on the cell surface. The remaining antigens were intracellular and were small- to medium-sized proteins. The surface antigens were the most significant in relation to the serological response in infected horses. They also reacted with sera from apparently healthy cattle, but the reas...
Tatarov G, Martinov S, Panova M.It was established that the complement binding reaction (CBR) is a suitable and very fast method for horse rhino-pneumonitis diagnostics. Cell cultural virus produced in cell cultures of pig kidneys was used as antigen. The antigen lots tested have no anticomplementary properties. Highest complement binding activity was evident in the non-diluted antigen, which discovered specific antibodies in immune serums. The CBR specificity was tested by the aid of homologous and heterologous serums and antigens. The titers of complement binding antibodies in the serums of 255 horses recovered from the di...
Liberatori J, Morisio Guidetti L, Conti A.By double diffusion in agarose gel, in well defined experimental conditions, cross reactions were observed between porcine beta-lactoglobulins and anti-bovine beta-lactoglobulin antisera. The immunological reactivity between these beta-lactoglobulins from a monogastric and the ruminant anti beta-lactoglobulin antiserum thus implies a certain degree of similarity between the monomeric beta-lactoglobulins examined and the dimeric of the ruminants. With the same antisera it also proved possible to demonstrate the presence of beta-lactoglobulins in the mammary secretions of another monogastric, na...
Nic An Ultaigh S, Ryan MF.Proteinases released during the in vitro maintenance of asynchronous cultures of the free-living nematode Caenorhabditis elegans were characterized on the basis of subunit composition, fluorogenic substrate specificity, inhibitor sensitivity and pH optima. Cysteine proteinases are present in the excretory-secretory products (ESP) as indicated by the hydrolysis of cathepsin fluorogenic substrates and confirmed by immunoblotting. Serine proteinases were predominant as indicated by substrate gel analysis and inhibitor studies. The presence of metallo-proteinases was also indicated by inhibitor st...
Magnuson NS, Perryman LE.The effect of adenosine on the mitogenic response of peripheral blood lymphocytes (PBL) and on the nucleotide pools of erythrocytes from normal horses, horses heterozygous for the combined immunodeficiency (CID) trait (carriers), and foals with CID was studied. When PBL from normal, carrier, and CID horses were stimulated by phytohemagglutinin (PHA), concanavalin A, or pokeweed mitogen, [3H]thymidine uptake was inhibited by adenosine (0.1 microM) to 1.0 mM) in a dose-dependent manner. Adenosine (100 microM) mediated inhibition of [3H]thymidine uptake was prevented in both normal and carrier ho...
Broström H, Hellström U, Ziverts I, Obel N, Perlmann P.In a preceding report we have shown that the lectin Helix pomatia A hemagglutinin (HP) binds to two subpopulations of neuraminidase-treated equine peripheral blood lymphocytes (PBL), constituting about 20% and 75% of PBL, respectively. The aim of the present study was to further characterize these HP+ cells in regard to other surface markers such as receptors for guinea pig erythrocytes (GPR+ cells), membrane-bound immunoglobulins (sIg+ cells), receptors for activated complement (C3R+ cells) and receptors for IgG (Fc alpha R+ cells). This was done by double marker analysis and by lymphocyte fr...
Mckelvie J, Foster AP, Hamblin AS, Cunningham FM.Intradermal injection of a Culicoides antigen extract (CAgX) induces T lymphocyte and eosinophil accumulation in the skin of horses with sweet itch. Blood mononuclear (BMN) cells from normal ponies proliferate when stimulated by mitogen (phytohaemagglutinin, PHA) or antigen (tetanus toxoid, TT) and, as shown here, release soluble factor(s) that induce eosinophil adherence. CAgX also caused concentration dependent proliferation of BMN cells from sweet itch and normal ponies [stimulation index: 29 (13) and 17 (7) for BMN cells from sweet itch and normal ponies, respectively during the active pha...
Wu D, Murakami K, Liu N, Konishi M, Muneta Y, Inumaru S, Kokuho T, Sentsui H.The equine interleukin-18 (IL-18) cDNA that contains the coding sequence was cloned and a recombinant baculovirus, named AcEIL-18, was constructed. The recombinant protein of the equine IL-18 was expressed by AcEIL-18 and its expression was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Insect cells infected with AcEIL-18 secreted a precursor IL-18 with 24 kilo dalton (kDa) into the culture supernatant. Western blot analysis showed that mature equine IL-18 about 18 kDa was also confirmed without co-expression of caspase-1. Culture supern...
Romantsov MG, Galimzianov KhM, Lokteva OM, Kovalenko AL, Stepanov AV.Search for drugs efficient in prophylaxis and treatment of dangerous infections (especially arboviral ones) is rather actual, since no specific therapy is available. Many-year investigations of interferon inductors showed that they had immunomodulating, antiviral and antiinflammatory effects and were low toxic. The present study demonstrated that the protective effect was the following: Venezuelan equine encephalitis (VEE)--cycloferon > amixin = ridostin, Rift Valley fever (RVF)--cycloferon > amixin > ridostin, predator pox (PP)--cycloferon > amixin = ridostin, that was obvious tha...
HORI J, AOKI K.Electrophoretic studies were made of normal horse and human serum albumins over the pH range 3.6–6.8 and at 25 °. The ionic strength of acetate or phosphate buffer used was 0.1, and the concentration of protein was 0.5% (g./100 ml.). Patterns were usually enantiographic and there were two (N and F1) or three (N, F1, and F2) boundaries in the pH range 3.6–5.2. The areas of the N and F1 boundaries changed continuously with pH, and the area of F2 was almost constant. The results were interpreted, in the same way as was previously done in the case of bovine serum albumin, by the isomerization...
Steinhardt J, Hiremath CB.Many of the stability characteristics of horse ferrihemo-globin (Hb+) in acid solutions, such as pH dependence and susceptibility to stabilization by iron ligands, are shared by human ferrihemoglobin, but striking differences between the two proteins exist. The most noticeable is the much greater rate of denaturation of the human protein at all pH values. Other differences include a shift to higher pH in the equi-librium between native and acid-denatured forms, differ-ences in the temperature at which the temperature effect on the equilibrium-pH curve reverses, a complete absence in human Hb+ ...
