The immune response in horses involves a complex network of cells, tissues, and molecules that work together to protect the animal from pathogens and other harmful agents. This process includes both innate and adaptive immune mechanisms. Innate immunity provides the first line of defense and involves components such as physical barriers, phagocytic cells, and the complement system. Adaptive immunity, on the other hand, is characterized by the activation of lymphocytes and the production of antibodies, which provide a targeted response to specific antigens. Key components of the equine immune system include T cells, B cells, and various cytokines that facilitate communication between immune cells. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and implications of immune responses in equine health.
Longworth KE, Smith BL, Staub NC, Steffey EP, Serikov VB.To determine whether a detergent can prevent most of the early effects of i.v. infusion with Escherichia coli endotoxin (< 100 ng/kg of body weight) in horses: marked pulmonary hypertension, acute leukopenia, and fever. Methods: 8 healthy adult horses (4 male, 4 female), 415 to 615 kg. Methods: Control and detergent experiments were performed in each horse while it was awake but sedated. In control experiments, 10 to 100 ng of E coli endotoxin/kg was given. In detergent experiments, 100 mg of detergent/kg was given 1 hour before injecting endotoxin, similar to the control experiments. Resul...
Kydd JH, Hannant D, Mumford JA.This study characterised bronchoalveolar leucocytes collected by lavage from five susceptible and two immune ponies before and after nebulised aerosol infection with equid herpesvirus-1 (EHV-1). Leucocyte counts and lymphocyte phenotypic analyses were performed using either differential staining or an indirect immunofluorescence assay with monoclonal antibodies specific for equine (Eq) CD4, CD5, CD8 and B lymphocytes. After EHV-1 infection, significant changes developed: a transient neutrophilia occurred on Day 2, coincident with a reduction in macrophage numbers and an EqCD5+, EqCD4+ and EqCD...
Momoi Y, Kato H, Youn HY, Aida H, Takagi S, Watari T, Goitsuka R, Tsujimoto H, Hasegawa A.Levels of granulocyte-colony stimulating factor (G-CSF) in the blood of horses were measured before and after a long-distance transportation to clarify the pathogenesis of transportation-induced fever. The serum G-CSF level was measured by its ability to stimulate growth in a mouse myeloblastic cell line, NFS-60. Of 26 horses transported for a long distance, 9 had fever more than 39.0 degrees C during or after transportation. After transportation, the serum G-CSF level significantly increased in horses with transportation-induced fever but not in those without fever, and the serum G-CSF level ...
Marr KA, Fairbairn SM, Page CP, Lees P, Cunningham FM.Antigen challenge involving exposure to straw and mouldy hay for 7 h produced lung function changes and neutrophil recruitment to the lungs in horses with chronic obstructive pulmonary disease (COPD). During the challenge, an increase in radiolabelled neutrophils in the lungs occurred, together with increased respiratory rate and pleural pressure. The role of platelet activating factor (PAF) in antigen-induced neutrophil accumulation, and increased pleural pressure and respiratory rate was investigated by administering the PAF receptor antagonist WEB 2086 to asymptomatic COPD horses prior to a...
Knowles DP.Infection of horses with the hemoprotozoan Babesia equi has been reported in southern Florida, US Virgin Islands, part of Asia, Russia, India, the Middle East, Europe, Africa, Australia, South America, Central America, Mexico, Philippine Islands and some Caribbean islands. The restrictions placed on the international movement of infected horses has refocused attention on potential methods to control or eliminate infection. Don Knowles here discusses the primary chemotherapeutic compounds that have been used; the current knowledge concerning immune responses that potentially contribute to contr...
Hines MT, Palmer GH, Byrne KM, Brassfield AL, McGuire TC.Bronchoalveolar lavage fluid (BALF) and peripheral blood were obtained from each of 17 adult Arabian mares and absolute numbers and relative lymphocyte proportions were determined for total T lymphocytes, using CD2 as a marker, CD4 + T lymphocytes, CD8 + T lymphocytes, CD5 + lymphocytes, and sIgM + B lymphocytes. The marked variation in BALF cell recovery resulted in wide variation in absolute values for each lymphocyte subset. The relative proportions of gated BALF lymphocytes were much less variable and provided a basis for comparison of lymphocyte subsets between the BALF and peripheral blo...
BonenClark GD, MacKay RJ, Ward RE, Sheerin B.To evaluate the humoral response of horses to vaccination, using a murine monoclonal anti-idiotypic antibody (A4) that shares an epitope with lipid A. Methods: Serum concentrations of antilipid A antibody and 1C9 (epitope on murine monoclonal antilipid A antibody) were measured serially during the period of vaccination with A4. Methods: 6 clinically normal adult ponies. Methods: Ponies were inoculated IM 3 times at monthly intervals with A4. Two weeks after each inoculation, serum was obtained and was assayed by ELISA for antilipid A and 1C9 concentrations. Additional vaccinations were given t...
Esser AF, Tarnuzzer RW, Tomlinson S, Tatar LD, Stanley KK.Lack of hemolytic activity of horse serum is an inherent property of horse C9. To understand the molecular reasons for this deficiency we have cloned C9 cDNA from a horse liver cDNA library and have sequenced the cDNA yielding the complete coding sequence for horse C9. Purification of C9 from horse plasma and microsequencing established the N-terminus of the mature protein and verified that the correct horse C9 cDNA clone had been isolated. The deduced amino acid sequence corresponds to a mature protein of 526 amino acids that is 77% identical to human C9. It has the same domain structure as h...
Sanada Y, Noda H, Nagahata H.The blastogenic response of lymphocytes from 16 newborn foals naturally infected with Rhodococcus equi was investigated, in order to evaluate the relationship between R. equi infection and depressed host response. Naturally infected foals showed evidence of R. equi infection at 5-6 weeks of age, as determined by clinical, haematological, bacteriological and serological methods. The blastogenic response of lymphocytes against phytohaemagglutinin was significantly depressed (stimulation index < 1.80; P < 0.01, P < 0.05) in R. equi-infected foals at 5-6 weeks of age compared with those o...
Grund CH, Lechman ER, Pezzuolo NA, Issel CJ, Montelaro RC.Equine infectious anaemia virus (EIAV) provides a model for examining the natural immunological control of a persistent lentivirus infection and for evaluating the efficacy of various vaccine strategies. As an initial characterization of antibody responses associated with protective or enhancing immune responses elicited by experimental infections or vaccinations, we have utilized synthetic peptide ELISA to characterize the fine specificity of antibodies to linear determinants of the EIAV surface glycoprotein, gp90. The data indicated that serum antibodies associated with protective or enhanci...
Jarvis GE, Evans RJ.Endotoxin has previously been shown to induce platelet aggregation in equine heparinised whole blood. This study aimed to determine whether platelet-activating factor or products of cyclo-oxygenase metabolism (thromboxane A2 or prostaglandins) were important in mediating the response of platelets to endotoxin. The effects of the following drugs on endotoxin-induced aggregation were investigated: aspirin, flunixin meglumine and carprofen (non-steroidal anti-inflammatory drugs); CV-3988 and WEB2086 (platelet-activating factor receptor antagonists); quinacrine (phospholipase A2 inhibitor). The ef...
Watson ED, Thomson SR.The density and distribution of MHC Class II positive cells and subpopulations of lymphocytes were studied in the endometrium of genitally normal mares and mares susceptible to endometritis. In genitally normal mares, more MHC Class II positive cells were present in the epithelium and stratum compactum during oestrus than dioestrus. Significantly more CD4+ and CD8+ lymphocytes were present in the stratum compactum than in the stratum spongiosum. CD4+ lymphocytes were present in greater numbers than CD8+ lymphocytes in the stratum compactum but approximately equal numbers were present in the st...
Moore BR, Krakowka S, Cummins JM, Robertson JT.Natural human interferon-alpha (nHuIFN alpha) was administered to actively training Standardbred racehorses with inflammatory airway disease (IAD). Inflammatory airway disease was characterized by poor exercise performance and inflammation and exudate in the upper and lower airway. Placebo, 50, 150, or 450 units(U) of nHuIFN alpha was administered orally for 5 consecutive days to eight horses per treatment group in a double-blind, randomized block design. Response to nHuIFN alpha was monitored by semiquantitative endoscopic examination score and cytologic examination of bronchoalveolar lavage ...
Barlough JE, Madigan JE, DeRock E, Dumler JS, Bakken JS.A Thoroughbred filly that developed clinical signs of equine granulocytic ehrlichiosis following inoculation with the human granulocytotropic ehrlichia was shown to be resistant to challenge with Ehrlichia equi, a closely related agent. This result further substantiates the close and potentially conspecific relationship between these two granulocytotropic ehrlichiae.
Swiderski CE, McClure JJ.The immune system is a complex interactive network. Defects in its function can be characterized broadly as being the result of actual deficiencies in the network or misdirection of normal immunologic functions. The assays that are available to detect deficiencies in the immunologic network barely scrape the surface of the possibilities. These assays primarily evaluate humoral immune function, but undetected defects in innate and cellular immunity are sure to exist. Although assays of humoral immunity have allowed the characterization of a number of immunodeficiency syndromes in horses, closer...
Cargile JL, MacKay RJ, Dankert JR, Skelley L.A monoclonal antibody (MAB) against equine tumor necrosis factor-alpha (Eq TNF) was used to investigate the role of TNF in cytokine, eicosanoid, and metabolic responses of Miniature Horses given endotoxin. Plasma concentrations of interleukin 6 (IL-6), lactate, thromboxane A2 metabolite, and prostacyclin metabolite (6-keto-PGF1 alpha) were measured in 10 Miniature Horses given 0.25 microgram of lipopolysaccharide (LPS; Escherichia coli O55:B5)/kg of body weight. Five horses were given Eq TNF MAB and 5 were given isotype-matched MAB as control. All horses were given 1.86 mg of antibody/kg by IV...
Kato H, Ohashi T, Nakamura N, Nishimura Y, Watari T, Goitsuka R, Tsujimoto H, Hasegawa A.Equine interleukin-1 alpha (IL-1 alpha) and IL-1 beta were molecularly cloned to establish a basis for research on inflammatory and immune responses in the horse. Equine peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS), and cDNA clones of equine IL-1 alpha and IL-1 beta covering the whole coding sequences were isolated from them. These equine IL-1 alpha and IL-1 beta clones contained open reading frames encoding 271 and 269 amino acids, respectively. The deduced amino acid sequence of equine IL-1 alpha showed 71.6% and 60.2% similarity with that of human ...
Wallace FJ, Emery JD, Cripps AW, Husband AJ.The ability of mucosally administered antigen to provide protection against Streptococcus equi ('Strangles') infections in horses was examined. First, an enzyme linked immunosorbent assay (ELISA) was developed to detect the immune status of horses to S. equi. This assay was used to select Strangles-naive horses for the study and also to monitor their response to immunisation. Potential vaccine candidates were: (a) orally administered paraformaldehyde killed S. equi; (b) intraperitoneally (IP) administered paraformaldehyde killed S. equi in a non-inflammatory adjuvant; (c) orally administered l...
Whalley JM, Love DN, Tewari D, Field HJ.A series of recombinant baculoviruses containing genes for glycoproteins C, D, H and L of equine herpesvirus 1 (EHV-1) have been constructed, and the EHV-1 products characterised by gel electrophoresis and immunoblotting. The EHV-1 glycoproteins expressed in insect cells were similar but not identical in apparent sizes to those expressed in EHV-1 infected mammalian cells. Each of the EHV-1 products was recognised by convalescent equine sera, indicating that they were all targets for an equine immune response. Mice immunised with baculovirus-expressed EHV-1 gD and gC acquired an enhanced abilit...
Grünig G, Triplett L, Canady LK, Allen WR, Antczak DF.Invading trophoblasts form endometrial cups in the endometrium of the pregnant mare. In the present study we characterized the maternal leucocyte response to endometrial cups from their formation to their regression. The maternal leucocyte response was correlated with the stages of trophoblast development. (1) Aggregates of CD4+ and CD8+ cells were present between the migrating and differentiating endometrial cup trophoblasts and surrounding the forming endometrial cups. (2) Numbers of CD4+ cells within the mature endometrial cups were much reduced. At the periphery of the endometrial cups CD4...
Hurwitz A, Finci-Yeheskel Z, Dushnik M, Milwidsky A, Shimonovitz S, Yagel S, Adashi EY, Mayer M.This study examines the effects of interleukin-1 (IL-1) on plasminogen activator (PA) activity and prostaglandin (PG) E production in pregnant mare serum gonadotropin (PMSG)-primed granulosa cells and the potential involvement of PGE in the regulation of ovarian plasminogen activation. Methods: Granulosa cells were obtained from PMSG-primed rat (27-day-old) ovaries and cultured in serum-free conditions for 48 hours in the absence or presence of IL-1 beta (10 ng/mL) with and without transforming growth factor-beta 1 (10 ng/mL). Cellular PA activity was measured through the conversion of plasmin...
Kampl B, Dominis-Kramaric M, Bacar-Huskic L.The activities of leukocyte alkaline phosphatase (l-AP) and serum gamma-glutamil transferase (gamma-GT), and total leukocyte counts were determined in horses submitted to the production of hyper immune sera against tetanus (Clostridium tetani). The purpose of this work was to investigate the prospective changes of mentioned parameters in horses under the described circumstances. In addition, the suitability of these parameters in assessing the health condition of the same horses had to be evaluated. The average total leukocyte count increased in one month from the values considered as physiolo...
Guo Y, Wang M, Zheng GS, Li WK, Kawaoka Y, Webster RG.In May 1993, a severe epidemic of respiratory disease began in horses in Inner Mongolia and spread throughout horses in China. The disease affected mules and donkeys as well as horses but did not spread to other species, including humans. The severity of the disease raised the question of whether the outbreak might have been caused by the new avian-like influenza viruses detected in horses in China in 1989 or by current variants ofA/equine/Miami/1/63 (H3N8) (equine-2) or by a reassortant between these viruses. Antigenic and sequence analysis established that all gene segments of the influenza ...
Lunn DP, Holmes MA, Schram B, Duffus WP.Equine immunoglobulin G is currently classified as consisting of five sub-isotypes: IgGa, b, and c, IgG(T), and IgG(B). The study of the role of these immunoglobulins in antigen-specific responses, and the examination of their functional properties would be greatly facilitated by the availability of monoclonal antibodies (Mabs) that distinguish between them. The production and characterization of two Mabs that recognize an IgG sub-isotype with the characteristics of IgG(ab) is described. The immunoglobulin identified by these Mabs had a heavy chain weight of 53 kDa, was of rapid cathodal elect...
Kanaly ST, Hines SA, Palmer GH.Rhodococcus equi, a facultative intracellular bacterium, causes chronic, often fatal granulomatous pneumonia in young horses and in humans with AIDS. The inability of host alveolar macrophages to kill intracellular R. equi results in the development of granulomas and progressive loss of pulmonary parenchyma. Clearance of the organism from the lung requires functional CD4+ T cells. The purpose of this study was to identify the cytokine effector mechanisms that mediate clearance of R. equi from the lung. Mice were treated with monoclonal antibodies (MAbs) to either gamma interferon (IFN-gamma) o...
Soutullo A, García MI, Bailat A, Racca A, Tonarelli G, Malan Borel I.Equine infectious anemia virus (EIAV) is a lentivirus causing a persistent infection in horses characterized by recurrent febrile episodes and high levels of viremia associated with a novel antigenic strain of the virus. The virus contains two envelope glycoproteins, gp90 and gp45, and four internal proteins, p26, p15, p11 and p9. Considering that the most infected horses are able to restrict EIAV replication to very low levels and that gp45 and p26 contain highly conserved epitopes among lentiviruses, it would be necessary to identify those conserved epitopes stimulating cellular and humoral ...
Jarvis GE, Evans RJ.Endotoxin has previously been shown to induce platelet aggregation in equine heparinised whole blood. This study aimed to determine whether platelet-activating factor or products of cyclo-oxygenase metabolism (thromboxane A2 or prostaglandins) were important in mediating the response of platelets to endotoxin. The effects of the following drugs on endotoxin-induced aggregation were investigated: aspirin, flunixin meglumine and carprofen (non-steroidal anti-inflammatory drugs); CV-3988 and WEB2086 (platelet-activating factor receptor antagonists); quinacrine (phospholipase A2 inhibitor). The ef...
Cao XZ, Lin YZ, Li L, Jiang CG, Zhao LP, Lv XL, Zhou JH.The threshold hypothesis of attenuated lentiviral vaccine considers that the type of host response to infections of lentiviruses depends on the viral load. To evaluate the correlation between viral loads of the attenuated vaccine strain of equine infectious anemia virus (EIAV) and their effects to induce protective immunity, longitudinal plasma viral loads in groups of horses inoculated with either an attenuated EIAV vaccine strain (EIAV(DLV125)) or sub-lethal dose of an EIAV virulent strain (EIAV(LN40)) were compared. Similar levels of plasma viral loads ranging from 10(3)-10(5) copies/mL wer...
Kaur N, Townsend H, Lohmann K, Marques F, Singh B.Rhodococcus equi establishes long-term pulmonary infection, survives in phagolysosomes of alveolar macrophages and causes pneumonia in foals. The failure of the foal to clear R. equi bacteria is believed to be due to its inability to produce IFN-γ and defects in Toll-like receptor(TLR) signaling. Lipid rafts sequester immune receptors such as TLRs and facilitate efficient cell signaling and therefore, a deficiency in accumulation of receptors in lipid rafts may result in failure to activate. We tested whether a Virulence Associated Protein A (VapA)/CpG vaccine against R. equi would impact the...
Nakken G, Kirk J, Fjordbakk CT.Autologous conditioned serum (ACS), i.e serum enriched with anti-inflammatory cytokines and growth factors, is a popular orthobiologic therapy used in equine practice. Costly specialized tubes containing glass beads are commonly used for ACS production. The objective of this in vitro study was to compare cytokine and growth factor levels in equine serum after incubation in three different tubes: commercial plastic ACS tubes (COMM); sterile 50 ml plastic centrifugation tubes (CEN); and 10 ml plastic vacutainer tubes (VAC). Blood from 15 healthy horses was incubated in the different tubes at 3...
Paulino PG, Peckle M, Mendonça LP, Massard CL, Antunes S, Couto J, Domingos A, Guedes Junior DDS, Cabezas-Cruz A, Santos HA. is the only tick species known to serve as a biological vector of for horses and other equids in Brazil. The protozoan is one of the causal agents of equine piroplasmosis, a major threat in horse breeding systems. Vector competence is closely linked to the pathogens' ability to evade tick defense mechanisms. However, knowledge of tick immune response against infections by hemoparasites of the genus is scarce. In the present study, the expression of genes involved in immune signaling pathways of adults' guts when challenged with a high or low parasitic load of was evaluated. This research...
Korhonen PA, Lilius EM, Hyyppä S, Räsänen LA, Pösö AR.Six trained Standardbred trotters exercised on a racetrack on 2 days with a 3-day interval. On both exercise days the horses trotted three different exercise bouts with increasing intensity with 60-min intervals. Exercise-induced stress was manifested as leucocytosis, an increase in the neutrophil:lymphocyte (N:L) ratio, and increased capacity to produce reactive oxygen species in the peripheral blood as indicated by an increase in whole blood chemiluminescence. The leucocytosis was mainly due to neutrophilia, which lasted for 6 h. Production of reactive oxygen species per single neutrophil sh...
Saini S, Singha H, Siwach P, Tripathi BN.Interleukin (IL)-4 and IL-10 activate plethora of immune cells and induce the humoral immune response. However, recombinant version of horse IL-4 and IL-10 has not been investigated to understand their immunomodulating activities. This study aimed to produce recombinant horse mature IL-4 and IL-10 in . Immune-modulating activities of recombinant horse IL-4 and IL-10 were investigated in peripheral blood mononuclear cells (PBMCs). Methods: Equine PBMCs were stimulated with recombinant IL-4 and IL-10. A proliferation of PBMCs was measured by XTT assay and cytokines induction was measured by enzy...
O'Brien MA, Holmes MA, Duffus WP.Anti-tetanus toxoid (TT) antibody (Ig) levels in the supernatant of cultured, pre-immunised equine peripheral blood mononuclear cells (PBMC) were measured by an indirect enzyme-linked immunoabsorbent assay (ELISA). Optimal anti-TT Ig production occurred at concentrations of stimulating, purified TT of between 0.001 and 0.1 micrograms ml-1, which varied depending on the cell concentration. Optimal anti-TT Ig production was most consistently produced when the cell concentration was 5 x 10(6) ml-1. At this cell concentration maximal anti-TT Ig was induced using 0.1 micrograms ml-1 TT. At a cell c...
Wernery U, Rodriguez Caveney M, Wernery R, Raghavan R, Laroucau K, Syriac G, Thomas SM, John J, Joseph M, Jose S, Joseph S, Woo P.Six horses were challenged experimentally with a strain of Burkholderia pseudomallei isolated from a fatal case of the infection in a dromedary camel years earlier in the Emirate of Dubai. Three horses were inoculated subcutaneously and in 3 the bacterium was administered by the oral route. Four of the horses became serologically positive based on reactions to one or more of the OIE described tests for glanders. B. pseudomallei was re-isolated from the 4 serological positive horses. Only one of the subcutaneously infected horses, developed fever for 3 days. The white blood cell values and the ...
Njoku CJ, Saville WJ, Reed SM, Oglesbee MJ, Rajala-Schultz PJ, Stich RW.Equine protozoal myeloencephalitis (EPM) is a disease of horses that is primarily associated with infection with the apicomplexan Sarcocystis neurona. Infection with this parasite alone is not sufficient to induce the disease, and the mechanism of neuropathogenesis associated with EPM has not been reported. Nitric oxide (NO) functions as a neurotransmitter, a vasodilator, and an immune effector and is produced in response to several parasitic protozoa. The purpose of this work was to determine if the concentration of NO metabolites (NO(x)(-)) in the cerebrospinal fluid (CSF) is correlated with...
Bannai H, Kambayashi Y, Tsujimura K, Nagashima T, Takebe N, Tominari M, Nemoto M, Ohta M.The antibody response in horses inoculated with 2 doses of a live equine herpesvirus type 1 vaccine with different vaccination intervals (1 to 3 months) was evaluated with regard to the persistence of virus-neutralizing (VN) antibodies. The durations for which the geometric mean VN titers were maintained significantly higher than those before the first vaccination (P<0.05) were up to 5 months in horses that received the vaccination with a 1-month interval (n=17) and 7 months for those that received it with a 2-month (n=17) or 3-month interval (n=14 or 17). The vaccination program with the 2...
Köhne M, Mönnig F, Papin J, Schöniger S, Tönissen A, Rohn K, Martinsson G, Schoon HA, Sieme H.The effects of standard uterine body and hysteroscopic insemination on endometrial health were investigated. For this purpose, 33 mares were assigned to five different protocols: control (no insemination; n = 7), sham AI (sham uterine body insemination; n = 6), sham HysAI (sham hysteroscopic insemination; n = 7), standard AI (standard uterine body insemination, 300 × 106 progressively motile sperms (PMS); n = 7) and HysAI (hysteroscopic insemination, 100 × 106 PMS; n = 6). Sampling included uterine swabbing for microbiological examination, cytology for determination of polymorphonucle...
Wong DM, Buechner-Maxwell VA, Manning TO, Ward DL.To evaluate the precision of intradermal testing (IDT) in horses. Methods: 12 healthy adult horses. Methods: IDT was performed on the neck of each horse by use of 2 positive control substances (histamine and phytohemagglutinin [PHA]) and a negative control substance. An equal volume (0.1 mL) for each injection was prepared to yield a total of 20 syringes ([4 concentrations of each positive control substance plus 1 negative control substance] times 2 positive control substances times 2 duplicative tests) for each side of the neck. Both sides of the neck were used for IDT; therefore, 40 syringes...
Milillo P, Traversa D, Elia G, Otranto D.Larvae of Rhinoestrus spp. (Diptera, Oestridae) infect nasal and sinus cavities of horses, causing a nasal myiasis characterized by severe respiratory distress. Presently, the diagnosis of horse nasal botfly relies on the observation of clinical signs, on the post mortem retrieval of larvae or on molecular assays performed using pharyngeal swabs. The present study was carried out to characterize larval somatic proteins and salivary glands of Rhinoestrus spp. in a preliminary assessment towards the immunodiagnosis of equine rhinoestrosis. Out of the 212 necropsied horses 13 were positive for th...
Bailey SR, Cunningham FM.To compare adherence of stimulated and unstimulated eosinophils from allergic and normal ponies to cultured equine vascular endothelial cells (equine digital vein endothelial cells; EDVEC) and examine the effect of eosinophil-derived factor(s) on cell adherence. Methods: Eosinophil adherence to unstimulated EDVEC or EDVEC pretreated with IL-1beta or supernatants from stimulated eosinophils was measured. Supernatants were also assayed for TNFalpha and IL-1beta-like bioactivity. Results: Adherence of unstimulated and rhIL-5 (10 ng/ml)-stimulated eosinophils from allergic ponies to rhIL-1beta-tre...
Chaiyabutr N, Wattanaphansak S, Tantilerdcharoen R, Akesowan S, Ouisuwan S, Naraporn D.African horse sickness (AHS) is a non-contagious, high mortality, and insect-borne disease caused by a double-stranded RNA virus from the genus Orbivirus. The study aimed to develop inactivated vaccines serotype 1 inactivated AHS vaccine (IAV) and to compare the effect of IAV on antibody responses in young naïve horses and adult horses pre-immunized with live-attenuated AHS virus (AHSV) serotypes 1, 3, and 4 live-attenuated vaccine (LAV). Unassigned: A total of 27 horses were vaccinated in two trials. Twelve AHS naïve young horses and 15 adult horses were divided into three groups of 4 and 5...
Raidal SL, Bailey GD, Love DN.Flow cytometric techniques were developed for the evaluation of oxidative burst activity in equine peripheral blood neutrophils and lymphocytes, as well as bronchoalveolar lavage derived pulmonary alveolar macrophages and lymphocytes. The oxidation of dichlorofluorescin was measured by the increased fluorescence of cells stimulated with phorbol myristate acetate or a variety of other stimulants. Flow cytometry was a suitable method for the evaluation of the intracellular oxidation in all cell populations evaluated. Analysis was rapid and cell separation before analysis was not required. Hetero...
Bergmann T, Lindvall M, Moore E, Moore E, Sidney J, Miller D, Tallmadge RL, Myers PT, Malaker SA, Shabanowitz J, Osterrieder N, Peters B, Hunt DF....Quantitative peptide-binding motifs of MHC class I alleles provide a valuable tool to efficiently identify putative T cell epitopes. Detailed information on equine MHC class I alleles is still very limited, and to date, only a single equine MHC class I allele, Eqca-1*00101 (ELA-A3 haplotype), has been characterized. The present study extends the number of characterized ELA class I specificities in two additional haplotypes found commonly in the Thoroughbred breed. Accordingly, we here report quantitative binding motifs for the ELA-A2 allele Eqca-16*00101 and the ELA-A9 allele Eqca-1*00201. Uti...
Wong DM, Young L, Dembek KA.Sepsis is common in foals and several treatments are used to facilitate recovery. Evidence in people suggests an association between low blood concentrations of thiamine, ascorbic acid, and cortisol and sepsis, with further evidence suggesting that administration of hydrocortisone, thiamine, and ascorbic acid may improve outcome. No information is available with regard to these treatments in foals. Objective: To compare blood concentrations of thiamine, ascorbic acid, and cortisol in healthy and ill foals. Methods: Fifteen healthy and 27 ill (septic and sick-nonseptic [SNS]) foals were evaluat...
Atwal OS, McDonell W.The pulmonary intravascular macrophages (PIMs) of equines contain a unique electron-dense surface coat that is predominantly composed of lipoproteins. A single exposure of inhalatory halothane causes mobilization of the surface coat into the endocytotic system of the PIMs, followed by expansion of the Golgi apparatus and its enrichment with acid phosphatase. Simultaneously, the cells of the lymphocytic series show hyperplasia in the form of mitotic changes inside the microvascular compartment of the lung. Halothane is known to cause acute and chronic hepatotoxicity because of its biotransforma...
Nikolakopoulos E, Kindahl H, Watson ED.Mares resistant (n=7) and susceptible (n=9) to persistent mating-induced endometritis were artificially inseminated (AI) during oestrus with chilled extended semen. Blood samples were collected from 30 min before AI, for 2 h after AI and again between 16 and 18 h after AI. Samples were assayed for oxytocin and the PGF2alpha metabolite 13,14-dihydro-15-keto PGF2alpha (PGFM). AI caused a significant increase in oxytocin concentrations in both the resistant and susceptible mares and there was no significant difference in oxytocin release between the two groups of mares. Mean PGFM concentrations w...
Rozario C, Martínez-Sobrido L, McSorley HJ, Chauché C.Influenza A viruses (IAVs) are important respiratory pathogens of horses and humans. Infected individuals develop typical respiratory disorders associated with the death of airway epithelial cells (AECs) in infected areas. Virulence and risk of secondary bacterial infections vary among IAV strains. The IAV non-structural proteins, NS1, PB1-F2, and PA-X are important virulence factors controlling AEC death and host immune responses to viral and bacterial infection. Polymorphism in these proteins impacts their function. Evidence from human and mouse studies indicates that upon IAV infection, the...
Santos AC, Nogueira CEW, Dos Santos Suñe Moraes B, Müller V, Mousquer MA, Leite FPL.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, ...
Lepage OM, Laverty S, Marcoux M, Dumas G.The effect of triamcinolone acetonide (0.09 mg/kg of body weight, IM) on serum osteocalcin concentration was studied. Two groups of horses were investigated and included clinically normal horses (group 1, n = 5) and horses with chronic obstructive pulmonary disease (group 2, n = 5). Before treatment, results of a t-test did not reveal any significant difference in serum osteocalcin concentration between the 2 groups. After treatment, a significant (P < 0.05) decrease in serum osteocalcin concentration was observed for both groups. Osteocalcin concentration in individual horses reached a min...
Palmer JE, Whitlock RH, Benson CE.Equine ehrlichial colitis was experimentally induced in 18 ponies, using Ehrlichia risticii-infected blood. Four ponies (group 1) were treated with oxytetracycline (6.6 mg/kg of body weight, IV, q 12 h), beginning 14 hours before inoculation and continuing for 5 days after inoculation. Four additional ponies (group 2) were treated similarly for 10 days after inoculation. The remaining 10 ponies were used as nontreated, infected controls. Clinical disease was delayed in 3 group-1 ponies and in 4 group-2 ponies. Protective immunity developed in the remaining pony that did not develop clinical di...
Hammond A, Bailey SR, Marr CM, Cunningham FM.Platelets contribute to the pathogenesis of human allergic airway disease. The aim of this study was to compare platelet activating factor (PAF)-induced platelet aggregation and thromboxane (Tx) production, plasma Tx and 5-hydroxytryptamine (5-HT) in ponies with recurrent airway obstruction (RAO), an hypersensitivity to inhaled antigens, and normal ponies, before and after antigen exposure. Plasma 5-HT was significantly higher in ponies with RAO but was not further increased by antigen challenge. There was no difference between PAF-induced platelet aggregation or Tx production, or in plasma Tx...
Catunda APN, Alves GES, Paes Leme FO, Carvalho AM, Leise BS, Johnson PJ, Faleiros RR.Inflammation and apoptosis in the hoof lamellar interface both contribute to the early stages of sepsis-associated laminitis, but it is not clear whether apoptosis is occurring before the onset of inflammation or is being provoked by inflammation. Apoptosis and inflammation were therefore measured in lamellar tissues obtained at different time points throughout the early stages of experimentally induced laminitis. Apoptotic cells and leukocyte were enumerated in archived paraffin embedded lamellar tissue samples from previous experiments in which acute laminitis was induced using Black Walnut ...
Rodrigues MA, Figueiredo L, Padrela L, Cadete A, Tiago J, Matos HA, Gomes de Azevedo E, Florindo HF, Gonçalves LM, Almeida AJ.Strangles is an extremely contagious and sometimes deadly disease of the Equidae. The development of an effective vaccine should constitute an important asset to eradicate this worldwide infectious disease. In this work, we address the development of a mucosal vaccine by using a Supercritical Enhanced Atomization (SEA) spray-drying technique. Aqueous solutions containing the Streptococcus equi extracts and chitosan were converted into nanospheres with no use of organic solvents. The immune response in a mouse model showed that the nanospheres induced a well-balanced Th1 and Th2 response charac...
Foster AP, Cunningham FM.Equine eosinophils and neutrophils are believed to play an important part in the protection of horses against parasitic and bacterial invasion. Eosinophils may also play a key role in the pathogenesis of equine inflammatory conditions such as the allergic skin disease, insect hypersensitivity. The factors which stimulate the respiratory burst of equine eosinophils and neutrophils are poorly understood. The first aim of the present study was to determine the effects of the phorbol ester, phorbol myristate acetate (PMA), which is believed to activate intracellular protein kinase C, and opsonised...
