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.
Broström H, Bredberg-Rådén U, England J, Obel N, Perlmann P.Cell-mediated immunity in horses with sarcoid tumor against sarcoid antigens was studied in vitro by means of mixed lymphocyte tumor cell culture assay and lymphocyte-mediated cytotoxicity of 52Cr-labeled target cells. When Mc-1 sarcoid cells were used as stimulatory cells for peripheral blood lymphocytes in the mixed lymphocyte tumor cell assay, a clear difference in the kinetics of the generated lymphocytic proliferative response could be detected between sarcoid and control horses. With sarcoid horses, their proliferative maximum was reached 3 days earlier than that of the control horses, a...
Murphy JR, McPherson EA, Lawson GH.80 mg sodium cromoglycate (SCG) was administered by inhalation to two COPD-affected animals known to have respiratory hypersensitivity to Micropolyspora faeni. SCG treatment 20-30 minutes prior to inhalation challenge with M. faeni prevented exacerbation of respiratory disease, usually seen 4-8 hours after challenge. duration of protection against antigen challenge after a single SCG treatment was 4-5 days. The duration of protection was not prolonged by reducing the frequency of antigen challenge. Multiple antigen challenge, using M. faeni and Aspergillus fumigatus, shortened the protective p...
Brown JE, Corstvet RE, Stratton LG.Two experiments incorporating 13 mares were conducted for the purpose of producing and monitoring intrauterine infection with Klebsiella pneumoniae. In the pilot study, the infection was produced with strains of K pneumoniae type 68 and type 10 isolated from the genital tract of stallions with a history of breeding problems. In the principal study, K pneumoniae type 68 was used to produce the infection. Tampons and guarded culture swabs were used to obtain uterine samples in the pilot study. In comparing the efficacies of isolation of K pneumoniae with the tampons and isolation with standard g...
Splitter GA, Incefy G, Iwata T, McGuire TC.Arabian horses with severe combined immunodeficiency disease (SCID) were evaluated for thymic hormone activities using thymic extracts and sera. Extracts prepared from thymus of SCID horses were able to increase the number of spleen cells responding to sheep red blood cells in irradiated, bone marrow-reconstituted mice. In addition, ultrafiltrates prepared from sera of these immunodeficient horses, which contained material with molecular weight of less than 50,000 Daltons could (a) induce a population of human bone marrow precursor cells to differentiate into cells bearing SRBC receptors and f...
Cline LJ, Crowle AJ.Evans Blue dye binds selectively, but with different avidities, to five major antigens in human serum. The anodic mobility of the antigen-dye complexes is greater than that of the antigens alone in crossed immunoelectrophoresis, which is of practical value for identification. We used this characteristic to show that in some human sera there is a population of alpha1-lipoprotein molecules that migrates electrophoretically in the beta-lipoprotein region, where in conventional zone electrophoresis it could be mistaken for beta-lipoprotein. We also demonstrate that horses, unlike rabbits, rarely m...
Prescott JF, Markham RJ, Johnson JA.Transformation of peripheral blood lymphocytes from pony foals vaccinated and subsequently infected with Corynebacterium equi was studied. Three foals were vaccinated on two occasions using a formalinized C. equi vaccine with aluminum hydroxide as an adjuvant. Three nonvaccinated foals served as controls. Foals were challenged intratracheally with 9 x 10(9) C. equi six weeks after the initial vaccination. Foals survived this infection for one to two weeks. Significant lymphocyte transformation in response to C. equi antigens was detected in two vaccinated foals at the third week after initial ...
Chen CL, Neilson JT, Kumar MS, Estes KS.Highly purified equine prolactin was prepared from equine pituitary glands (hypophysis) by serial extractions with water at pH 5.5, 0.1 M (NH4)2SO4 at pH 4.0, and 0.25 M (NH4)2SO4 at pH 5.5 to remove other hormones, and then finally with 70% ethanol at pH 9.3 to 10.0 to extract prolactin. Preliminary purification of the extract involved salting out other substances with 0.1% NaCl at pH 9.0. Prolactin was precipitated out by adding three times the volume of 95% ethanol at 4 C. This prolactin preparation had a biological potency of 24 IU/mg. Further purification by isoelectric focusing on a pH g...
Worthington RW, Mülders MS.Antibodies against epsilon toxin were isolated from hyperimmune horse serum by affinity chromatography. Purified epsilon prototoxin covalently bound to Affigel 202 was used as immunosorbent, and antibodies were eluted with 6.0 M guanidine chloride. In a single run 80 mg of antibody could be recovered from a 20 microliter column of immunosorbent. The antibody was shown to belong to the IgG(T) class of immunoglobulins.
Deem DA, Traver DS, Thacker HL, Perryman LE.Immunologic deficiency was suspected in an 18-month-old Standardbred horse with persistent fever, multifocal bacterial infection, and neutropenia with a large number of immature neutrophils. Serum protein electrophoresis revealed marked depression of the gamma-globulin fraction (0.2 g/100 ml). Immunologic testing and histologic examination of lymphoid tissues identified the immune deficit as agammaglobulinemia. Serum concentrations of immunoglobulin (Ig)G and IgG(T) were initially low and declined with time; IgM and IgA were not detectable. The horse failed to produce antibodies when inoculate...
Lawson GH, McPherson EA, Murphy JR, Nicholson JM, Wooding P, Breeze RG, Pirie HM.The sera of horses affected and not affected with chronic obstructive pulmonary disease (COPD) were examined for precipitins to Micropolyspora faeni and Aspergillus fumigatus. Precipitins to both antigens were not restricted to COPD cases but occurred more frequently in animals affected with COPD. Many animals without detectable precipitins responded clinically to inhalation challenge with these antigens.
Matthews AG.Three major antiprotease components in equine serum were identified and characterised. These were the acidic prealbumin Pr, the homologue of human alpha-1 antitrypsin and 2 protease binding proteins, the acidic prealbumin Xc and alpha-2 macroglobulin, both capable of inhibiting the proteolytic activity of trypsin, but with only limited inhibitory effect on its esterolytic activity. The possible role of these serum antiproteases in the onset of chronic obstructive pulmonary disease (COPD), analogous to the hereditary dysproteinaemia of alpha-1 antitrypsin in man, was investigated. There was no ...
McDonald TL, Burger D.Initial separation and concentration of Clq from fresh, normal equine serum was accomplished by precipitation in 0.02 M acetate buffer, pH 5.5, at 4 degrees for 24 h. The re-dissolved precipitate was clarified by centrifugation at 80,000 g for 1 h and then dialysed against Tris-HCl buffer (0.05 M, pH 8.0) containing 10-3 M EDTA. The clarified dialysate remained biologically active at 5 degrees for at least 4 weeks. Biological activity of equine Clq was determined by assay of its ability to agglutinate sensitized sheep erythrocytes (EA). Following ammonium sulphate fractionation, Sepharose 4B g...
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...
Science (New York, N.Y.)June 22, 1979
Volume 204, Issue 4399 1317-1319 doi: 10.1126/science.451540
Bailey E, Stormont C, Suzuki Y, Trommershausen Smith A.A system of equine lymphocyte alloantigens designated ELA, is identified, and it is shown that the locus or loci controlling these markers must be closely linked to the locus controlling markers in the A system of horse blood groups. Among 29 offspring in two stallion families there was evidence for one recombinant. Lod scores for linkage between the A and ELA loci in the two families were 3.61 and 3.33, respectively, for theta equal to 0.
Fujimiya Y, Perryman LE, Crawford TB.Antibody-dependent cellular cytotoxicity and direct cytotoxicity assays were performed with equine infectious anemia virus-infected target cells, equine leukocytes, and equine anti-equine infectious anemia virus antibody to determine whether these mechanisms play a role in controlling viral replication in equine infectious anemia. Direct cytotoxicity was observed by using peripheral blood mononuclear cells from 7 of 10 infected horses. Antibody-dependent cellular cytotoxicity was not observed. The antibody-dependent cellular cytotoxicity reaction in horses was then studied by using sheep eryth...
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...
Roumillat LF, Feorino PM, Lukert PD.Infection of a human lymphoblastoid cell line (Jijoye line derived from a Burkitt lymphoma which contains Epstein-Barr virus) with equine herpesvirus 1, maintained and observed for 53 days, was characterized by the continuous production of infectious extracellular and intracellular virus. Maximum virus production correlated with active cell multiplication. Less than 15% of the cells possessed viral capsid antigen at any one time. Five percent of the cells in the Jijoye line possess Epstein-Barr viral capsid antigen; 80% of the Epstein-Barr viral caspid-containing cells also contained equine he...
Leid RW.The investigation of the mast cell-basophil products has progressed from studies directed solely at implicating histamine or serotonin in allergic diseases to molecular definitions of pathways to target cell activation and mediator release. In addition, within the last several years the detection and molecular characterization of the many other mediators of immediate hypersensitivity have begun. This area should continue to prove a fruitful arena in the future. Identification of the physiologic importance of these mediators in the heaves syndrome or other potential equine allergic syndromes ma...
de Boer GF, Osterhaus AD, van Oirschot JT, Wemmenhove R.The prevalence of antibodies to various viruses was investigated in a series of serum samples collected from horses in the Netherlands between 1963 and 1966 and from 1972 onwards. Neutralizing antibodies to equine rhinopneumonitis virus, equine arteritis virus and to equine rhinovirus types 1 and 2 were detected in respectively 76%, 14%, 66% and 59% of the equine serum samples tested. The observed incidence of serum samples positive to equine adenovirus in the complement fixation test was 39%. Precipitating antibodies to equine infectious anaemia virus were detected only in serum samples from ...
Cummings JF, de Lahunta A, Timoney JF.Four cases of neuritis of the cauda equina (NCE) were studied by light and electron microscopy. Examination of sacral intradural rootlets revealed inflammatory cell infiltrates and an array of myelinated fiber changes which included myelin stripping by invading mononuclear cells and macrophages, as well as splitting and vesiculation of myelin lamellae without obvious participation by leukocytes. More distally in the extradural roots, there was marked granulomatous inflammation, and demyelinative changes were overshadowed by widespread evidence of irreversible axon damage. In all cases, unusual...
Moriarty KM, Brown MF, Sutton RH.Auto-immune, haemolytic anacmias (AHA) of man (Dacie, Citation1963) and domestiicated animals (Schalm, Citation1965; Farrelly et al., Citation1966; Lapras and Oudar, Citation1971) are classified either as idiopathic or secondary to an underlying disease process (Pirofsky, Citation1969). In both categories antibodies active against the indivual's own erythrocytes are formed. These auto-antibodies are of two types being either warm or cold-acting. Warm-acting antibodies are most effective at 37°C, belong to the IgG class of immunoglobulins, and are incomplete in that, generally, they do not cau...
Czernomysy-Furowicz D, Silecka A, Nawrotek P, Jankowiak D, Karakulska J, Furowicz A.The research was conducted on clinically healthy mares (n = 40) and foals (n = 78) during Y. pseudotuberculosis associated enzootics. The animals were divided into groups: I to IV--mares, IA to IVA--their offsprings, IB to IVB--foals which mothers were not treated with any medicaments. The animals in group I, IA and IB were injected with PBS; in group II, IIA and IIB--with Y. pseudotuberculosis strain-based vaccine, in group III, IIIA and IIIB--with P. acnes strain-based immunostimulator; in group IV, IVA and IVB--with P. acnes strain-based immunostimulator and (5 days after the immunostimulat...
Pycock JF, Allen WE.The neutrophil is involved in the defence of the mare's uterus against micro-organisms. The ability of Streptococcus zooepidemicus and its growth products to induce shape changes or directional locomotion (chemotaxis) of equine neutrophils was investigated; no effect was found.
Goto I, Kamada M, Inaba M, Maede Y.A protein A-hemolytic plaque assay was applied to detect immunoglobulin (Ig)-producing cells in horse peripheral blood, using pokeweed mitogen as a B lymphocyte activator. A maximum number of Ig-secreting cells was obtained when horse peripheral blood lymphocytes were cultured in a medium containing horse serum. The number of Ig-secreting cells in young horses (2 years old) was lower than that in adult horses (6 to 23 years old). In addition, the plaque formation was unchanged from blood samples kept at 4 degrees C for 24 hours, while blood samples kept for 72 hours did not yield plaques. Thes...
Edwards KE, Stevens S, Woodward CB, Tweeten KA.Counterimmunoelectrophoresis was evaluated as a method to distinguish urine of human origin from that of equine origin. The procedure used anti-equine serum and anti-human serum antibodies that had been solid-phase absorbed to eliminate species cross-reactivity. Counterimmunoelectrophoresis reliably detected contamination of equine urine by human urine to a level of 10% with a minimum sensitivity to about 2% contamination. Compared with double diffusion, counterimmunoelectrophoresis was approximately 10 to 15 times more sensitive in the detection of urine proteins.
Kawamura S, Hirayama K, Mitsuoka T.Two chromogenic Limulus amebocyte lysate systems were evaluated for the measurement of endotoxic activity in feces of normal horses. Fecal extracts had neither non-specific nor inhibitory effect on the test reaction, and the two systems with different specificity showed equivalent results. Endotoxic activities in feces of healthy horses averaged 5.7 +/- 2.8 microns/g wet weight. Correlation between the endotoxin levels and the fecal microbial flora could not be determined.
Molenda J.Using the indirect hemagglutination test, antibodies against Enterobacteriaceae common antigen (CA) were tested in the sera of 123 horses, 142 cows, 108 sheep, 142 mature pigs and 60 piglets (3-4 weeks of age). Anti CA antibody level and antibody titers for somatic antigens (phenol-water extracts) various serogroups of E. coli (0149, 0138, 0115, 078, 09) and S. typhimurium were compared. Ca antibodies in titer equal or higher than 1:15 were found to occur in 100% of the examined horses and cows, while in the sera of 92% sheep, 80% of mature pigs and 60% of piglets antibodies to the common Ente...