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.
Sahu SP, Pierson RE, Dardiri AH.Actively growing culture of contagious equine metritis (CEM) bacteria or infective exudate (or both) were inoculated intrauterine in pony mares. A direct relationship was observed between (i) appearance and duration of cervicitis and vaginitis and (ii) vaginal exudate. Clinical signs appeared 1 to 3 days after mares were inoculated and lasted 7 to 23 days. In the acute phase of infection, all uterine and cervical samples yielded CEM bacteria. In the asymptomatic stage of infection, CEM bacteria were not isolated from uterine and cervical samples; however, in 33%, 28%, and 20% of the pony mares...
Fernandez C, Möller G.After a primary immune response to the alpha 1-6 epitope of dextran B512, dextran high responder strains exhibit a specific inability to produce IgM and IgG antibodies against this epitope, although they gave an expected secondary response to horse erythrocytes. Spleen cells from dextran-primed and-suppressed mice responded well to dextran after transfer to lethally irradiated previously untreated mice, indicating that tolerance or exhaustive proliferation of dextran reactive B cells is not responsible. Thymus-dependent dextran-protein conjugates also induced specific suppression. Suppression ...
Jansen BC, Knoetze PC.An intramuscular injection of 8-16 Lf tetanus toxoid in water-in-oil emulsion protected adult horses against tetanus for at least 128 weeks. A booster dose of 8 Lf toxoid in aqueous solution protected them for a further period of at least 3 1/2 years. Colostral immunity protected foals for at least 10 weeks. An intramuscular injection of 8 Lf toxoid in water-in-oil emulsion given to foals from immune dams when they were 10-18 weeks old did not elicit any antibody response. They did respond, however, to a booster injection of 8 Lf toxoid in aqueous solution given 12 weeks after the first dose. ...
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...
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 ...
McPherson EA, Lawson GH, Murphy JR, Nicholson JM, Breeze RG, Pirie HM.Micropolyspora faeni and Aspergillus fumigatus were identified as common causes of respiratory hypersensitivity in horses affected with chronic obstructive pulmonary disease (COPD). Rye grass pollen and an Actinomycete evoked respiratory allergy in a few horses. Not infrequently, individual horses were found to have respiratory hypersensitivity to two or more antigens. The methods used to examine for allergy were intradermal testing and inhalation challenge with environmental antigens. An intradermal test using an M faeni extract was demonstrated to be suitable for diagnostic use in horses pre...
Burrows GE.Repeated exposure of ponies in Escherichia coli endotoxin resulted in attenuation of the packed cell volume, beta-glucuronidase, capillary refill time and neutrophil responses usually accompanying endotoxin administration. An overall decrease in severity of clinical response including reduced mortality was also apparent in ponies with repeated endotoxin exposure. Modification of the febrile response was not observed in any of the experimental groups.
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...
Clayton HM, Duncan JL.Following infection with 8000 Parascaris equorum eggs in two- to four-week-old foals reared under worm-free conditions a high percentage of the infective dose completed its tissue migration and returned to the small intestine. Patent infections were establisehd between 81 and 104 days after infection and high faecal egg counts were recorded. A group of six- to 12-month-old foals, which had been either reared under worm-free conditions or exposed to natural ascarid and strongyle infections on pasture, received a similar infection of 8000 P equorum eggs. Compared with the younger foals there was...
Murphy JM, Severin GA, Lavach JD, Hepler DI, Lueker DC.A modified Bacillus Calmette-Guerin (BCG) preparation was used successfully in the treatment of 7 cases of equine sarcoid. The BCG preparation was injected into the lesions. The longest period of remission has been 24 months, and the shortest period of remission has been 9 months, with no signs of recurrence of the tumor in any of the presented cases.
Halliwell RE, Fleischman JB, Mackay-Smith M, Beech J, Gunson DE.Twenty-five horses with chronic pulmonary disease were skin tested with allergenic extracts of 24 molds, 4 thermophilic actinomyces, barn dust, hay dust, soya-bean mill dust, and grain mill dust. The results were compared with those obtained on 25 normal horses. Between the 2 groups of horses, there was a highly significant difference in positive skin test results at 30 minutes and 4 hours.
Corradin G, Chiller JM.Murine T-lymphocyte specificity was determined in a system of antigen driven in vitro T-cell proliferation using cytochrome c molecules from different species, their derived peptides and reconstituted hybrid proteins. It was observed that primed T cells could discriminate between peptide fragments which differed from each other at a single amino acid residue. These conclusions were substantiated by the pattern of cross-reactivity noted in the response of closely related cytochrome c proteins as well as when artificial hybrid molecules reconstituted by the covalent linkage of peptide fragments ...
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...
Jörg A, Portmann P, Fellay G, Dreyer JL, Meyer J.An improved and short method is described for the isolation of intact eosinophilic leukocytes from horse blood with high yield (1--1.5 g/20 l). Viability and purity of the preparations were verified by light and electron microscopy and by the trypan blue exclusion test. Isolated eosinophils were 98--100% pure, intact and viable, and they could be shown to phagocytise immune-complexes.
Bennett D.The gross and histological features of multiple bone infection in two foals are described. In both cases the lesions were confined to the region of the growth plate. Bone and, in some cases, growth plate cartilage destruction has occurred associated with an extensive inflammatory cell infiltration. The significance of the pathological observation is discussed in relation to the pathogenesis of bone infection in the foal.
Veldman JE, Keuning FJ, Molenaar I.Two times sublethal total body-X-irradiation with weekly local thymus irradiation established a T-cell deprived experimental model in rabbits. Humoral immunity reactions in draining lymph nodes have been analyzed histologically and at the submicroscopical level after challenge with Salmonella Java vaccine, horse spleen ferritin, horse-gamma-globulin, a chemical sensitizer oxazolone (2 phenyl-4-ethoxymethylene-5-oxazolone) and after skin allografting respectively. The time sequence studies in these animals with an 'isolated B-cell system' are compared with similar experiments in normal non-irra...
Baker EF, Sasso DR, Maness K, Prichard WD, Parker RL.In 1971, more than 370 horses in south Texas were studied with respect to their clinical, virologic, and neutralizing antibody responses to vaccination with Venezuelan equine encephalomyelitis (VEE) strain TC-83. This study confirms reported findings that the vaccine used in the 1971 epizootic in the lower Rio Grande Valley of Texas was safe and efficacious. Vaccinal virus viremia titers were generally below the postulated infection threshold of epizootic vectors. In general, reactions to the vaccine were minimal and transient, with no observed abortions or deaths attributable to use of the va...
Woode GN, Bew ME, Dennis MJ.Inoculation at birth with a live attenuated strain of a bovine rotavirus isolated in the USA (scourvax-reo) induced protection in five gnotobiotic calves seven to 21 days later against a UK isolate of pathogenic bovine rotavirus. However, no protection was induced in three calves challenged three to five days after vaccination. There was a close antigenic relationship demonstrated between the two bovine rotavirus isolates. In contrast only one of three gnotobiotic calves inoculated with foal rotavirus, and one of three with human rotavirus, were protected against bovine rotavirus challenge. Pr...
Hodgin EC, McGuire TC, Perryman LE, Grant BD.Delayed hypersensitivity (DH) responses of normal and immunodeficient horses were evaluated with antigens [dinitrochlorobenzene (DNCB), keyhole limpet hemocyanin (KLH)] and phytolectins [phytohemagglutinin (PHA), concanavalin A (Con A)]. Immunologically normal horses sensitized with 5 daily applications of 2 mg of DNCB developed positive skin reactions upon challenge with 0.4 mg of DNCB. The delayed onset of the reaction and the predominately mononuclear cell infiltration at the test site indicated these were DH reactions. Normal horses sensitized with 500 microgram of KLH and challenged with ...
Barber TL, Walton TE, Lewis KJ.Twenty-nine horses were vaccinated with a trivalent (Venezuelan, eastern, and western) inactivated equine encephalomyelitis virus vaccine. The vaccine purchased for this study was the only one licensed and commercially available in May, 1975. Plaque-neutralizing and hemagglutinin-inhibiting antibodies in response to each of the 3 equine encephalomyelitis viruses were determined after vaccination. Horses had rising levels of plaque-neutralizing and hemagglutinin-inhibiting antibodies shortly after injection with the 1st and 2nd doses of the vaccine (given 3 weeks apart) and were refractory to c...
Moorthy AR, Spradbrow PB.Two strains of Chlamydia psittaci were isolated from the nasal tract of horses with acute respiratory disease. These 2 isolates (NS 121 and NS 172) were characterized as chlamydia on the basis of their morphology, tinctorial property, growth in chicken embryos, inability to grow on bacterial media and their possession of chlamydial common complement fixing group antigen. They were identified as C. psittaci on the basis of resistance to sodium sulphadiazine. The present strains were not pathogenic to mice and guinea pigs and non-toxigenic. They induced antibodies and caused latent infection in ...
Semrad SD, Moore JN.Previous work has shown repeated low doses of flunixin meglumine (FM) inhibit thromboxane production in normal horses. Enhanced concentrations of thromboxane in serum occurred after the drug therapy was discontinued. Our study was performed to evaluate the effects of low doses of FM in horses repeatedly challenged with endotoxin. Group I horses received E. coli endotoxin (0.1 microgram/kg IV) at 0 and 90 h. Group II horses received endotoxin and were also treated with FM (0.25 mg/kg IV) at 2, 10, 18, 26, 34, and 42 h after the initial administration of endotoxin. Clinical signs of endotoxemia ...
Lunn DP, Soboll G, Schram BR, Quass J, McGregor MW, Drape RJ, Macklin MD, McCabe DE, Swain WF, Olsen CW.Equine influenza virus infection remains one of the most important infectious diseases of the horse, yet current vaccines offer only limited protection. The equine immune response to natural influenza virus infection results in long-term protective immunity, and is characterized by mucosal IgA and serum IgGa and IgGb antibody responses. DNA vaccination offers a radical alternative to conventional vaccines, with the potential to generate the same protective immune responses seen following viral infection. Antigen-specific antibody isotype responses in serum and mucosal secretions were studied i...
Gilger BC.This review, which is part of the "Currents in One Health" series, describes the importance of the study of immune-mediated ocular disease in the development of innovative therapeutics, such as cell and gene therapy for the eye. Recent examples of cell and gene therapy studies from the author's laboratory are reviewed to emphasize the importance of One Health initiatives in developing innovative therapies for ocular diseases. Spontaneous immune-mediated corneal disease is common in horses, cats, dogs, and humans. Autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) injected subconju...
Gilger BC, Malok E, Cutter KV, Stewart T, Horohov DW, Allen JB.Equine recurrent uveitis (ERU), a chronic, recurrent inflammation primarily of the anterior uveal tract, is the most common cause of blindness in horses. Recently, T-lymphocytes have been found to be the most numerous cell type to infiltrate the anterior uveal of horses with ERU. In the present study, we characterized the T-lymphocyte population in the anterior uveal tract of eyes of horses with chronic ERU by evaluating the microscopic appearance (histopathologic features), the T-lymphocyte subsets, and the relative levels and amounts of T-lymphocyte cytokine mRNA in the anterior uvea. Seven ...
Bailey E, Albright DG, Henney PJ.Foals with the Ca blood group antigen on their RBC were given colostrum with anti-Ca antibodies (6 foals) or colostrum without anti-Ca antibodies (6 foals). The PCV were determined at birth and 2, 4, and 6 days after birth for the foals in each group. Significant differences were not observed for the PCV between the 2 groups, indicating that foals were not adversely affected by ingesting colostrum with the anti-Ca antibody. Standardbred mares without the Aa blood group antigen were evaluated to determine whether production of anti-Ca antibodies influenced production of anti-Aa antibodies. Of 2...
Srivastava SK, Barnum DA.Lymphocyte stimulation was observed in whole equine blood in the presence of phytohaemagglutinin and M protein extracted from a typical strain of Streptococcus equi. Blood samples were collected from several healthy horses and horse and pony foals and cultured in vitro with varying concentrations of phytohaemagglutinin and M protein for several days. Phytohaemagglutinin was found to induce lymphocyte stimulation in these animals. Highest mean stimulation indices in horse foals (49.3 +/- 24.4) and pony foals (54.7 +/- 32.0) were observed with 0.625 and 1.25 micrograms/mL phytohaemagglutinin, re...
Balasuriya UB, Heidner HW, Davis NL, Wagner HM, Hullinger PJ, Hedges JF, Williams JC, Johnston RE, David Wilson W, Liu IK, James MacLachlan N.Replicon particles derived from a vaccine strain of Venezuelan equine encephalitis (VEE) virus were used as vectors for expression in vivo of the major envelope proteins (G(L) and M) of equine arteritis virus (EAV), both individually and in heterodimer form (G(L)/M). The immunogenicity of the different replicons was evaluated in horses, as was their ability to protectively immunize horses against intranasal and intrauterine challenge with a virulent strain of EAV (EAV KY84). Horses immunized with replicons that express both the G(L) and M proteins in heterodimer form developed neutralizing ant...
Tsunoda RH, Serrano-Recalde EC, Arruda RP, Oliveira BMM, Pinto SCC, Celeghini ECC.The aim was to evaluate effects of addition of pentoxifylline to skimmed milk semen extender on uterine inflammatory response. Thirty-six estrous cycles of 15 mares were randomly divided into five groups for artificial insemination (AI): Control: mimicking the AI procedure (n = 7); Extender: deposition of skimmed milk based extender (n = 7); Extender + PTX: skimmed milk based extender plus pentoxifylline (7.18 mM; n = 8); Semen: semen diluted with extender without pentoxifylline (n = 7), and Semen + PTX: semen diluted with extender containing pentoxifylline (n = 7). M...
Hamouzová P, Drábková Z, Stehlíková Š, Řeháková K, Čížek P, Dobešová O, Jahn P, Doubek J.This study determined Tregs and inflammatory cytokines in BALF and peripheral blood (PB) of adult horses with mild and severe asthma and different BALF cytological inflammation profiles. Horses of diverse breeds with asthma (age range: 2-20 years, n = 24) were divided into groups according to the number of points obtained in a standardized clinical scoring system (mild-moderate equine asthma - MEA, severe equine asthma - SEA) and according to the inflammation type based on cytological finding. Plasma levels of IFN-γ, IL-4, IL-10, IL-17 and MMP-9 in the BALF were determined by ELISA. Tregs ...
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...
Go YY, Zhang J, Timoney PJ, Cook RF, Horohov DW, Balasuriya UB.Extensive cell culture passage of the virulent Bucyrus (VB) strain of equine arteritis virus (EAV) to produce the modified live virus (MLV) vaccine strain has altered its tropism for equine CD3(+) T lymphocytes and CD14(+) monocytes. The VB strain primarily infects CD14(+) monocytes and a small subpopulation of CD3(+) T lymphocytes (predominantly CD4(+) T lymphocytes), as determined by dual-color flow cytometry. In contrast, the MLV vaccine strain has a significantly reduced ability to infect CD14(+) monocytes and has lost its capability to infect CD3(+) T lymphocytes. Using a panel of five re...
Segabinazzi LGTM, Canisso IF, Podico G, Cunha LL, Novello G, Rosser MF, Loux SC, Lima FS, Alvarenga MA.Microorganisms, including pathogenic or opportunistic bacteria and fungi, may gain access to the uterus during breeding, and infectious endometritis plays a major role in equine subfertility. This study aimed to assess the post-breeding inflammatory response, endometrial culture, and embryo recovery of mares susceptible to persistent breeding-induced endometritis (PBIE) treated with plasma-rich (PRP) or -poor (PPP) plasma. Mares (n = 12) susceptible to PBIE had three cycles randomly assigned to receive intrauterine infusions of lactate ringer solution (LRS, control), or autologous PRP or PPP p...
Chiaradia E, Gaiti A, Terracina L, Avellini L.Physical exercise induces a reduction of immune defences and an imbalance of red-ox status. In this study plasma levels of cysteine and homocysteine (Hcy) were determined in horses before and after submaximal treadmill exercise as well as the effect on horse lymphocyte proliferation. The exercise induced a significant increase in plasma Hcy levels, which remained high both after the 20 min recovery period and after 2 h of rest. Moreover, a reduction of lymphocyte responsiveness to the proliferative stimulus induced by Concanavalin A was observed. The effects of different Hcy concentrations on ...
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...
Fumuso E, Giguère S, Wade J, Rogan D, Videla-Dorna I, Bowden RA.Endometrial mRNA expression of the pro-inflammatory cytokines interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha) was assessed in mares resistant (RM) or susceptible (SM) to persistent post-breeding endometritis (PPBE). Eight RM and eight SM, were selected based on reproductive records and functional tests out of a herd of 2,000 light cross-type mares. Three experiments were done to study transcription patterns in (i) basal conditions; (ii) after artificial insemination (AI); and (iii) after administration of an immunomodulator at time of artificial ...
Watson ED, Sertich PL, Zanecosky HG.Ovulation has been likened to an inflammatory process. Inflammatory cells accumulate in the ovulating follicle, presumably because of chemotactic factors. Chemotactic activity was measured in fluid aspirated from follicles of estrous mares 0, 12, 24, and 36 hours after ultrasonographic detection of a 35-mm follicle and IV treatment with 2,500 IU of human chorionic gonadotropin. Chemotaxis was assessed by measuring directional migration of equine neutrophils under agarose. Follicular fluid acted as a chemoattractant for neutrophils, but there was no significant difference in chemotactic activit...
du Toit N, McGorum BC, Pemberton AD, Brown J, Dacre KJ.Cyathostomins (Cyathostominae) are regarded as the most pathogenic equine nematode worldwide. These nematodes are difficult to control in equine populations due to emerging anthelmintic resistance and evasion of encysted larval cyathostomins to regular modern anthelmintics. Mast cells and their proteinases have been shown to play a role in the mammalian immune response to nematode infections. Involvement of mast cells and mast cell proteinases in the equine immune response to cyathostomin infection is proposed. A technique was established to perform immunohistochemical staining using polyclona...
Mateo-Otero Y, Zambrano F, Catalán J, Sánchez R, Yeste M, Miro J, Fernandez-Fuertes B.In several mammalian species, acute endometritis driven by the recruitment of polymorphonuclear cells (PMN) occurs in response to semen. These PMNs release DNA to form neutrophil extracellular traps (NETs) in cattle, horse and human, leading to sperm entrapment. While there is no evidence of this phenomenon occurring in donkeys, artificial insemination (AI) with frozen-thawed semen, which results in very poor pregnancy rates, leads to a large PMN recruitment to the uterus. Objective: To investigate whether donkey semen can trigger NET release (NETosis) and if excessive NETosis occurs in respon...
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...
Saeidi E, Mansoori Yarahmadi H, Fakhraei J, Mojahedi S.The objectives of this study were to determine the effects of dietary prebiotic fructooligosaccharides (FOS) from inulin and Enterococcus faecium on nutrient digestibility, fecal pH, and some blood parameters. In this experiment, twelve adult Kurdish horses with average bogy weight of 416 ± 43.3 kg and age averaging 6 ± 1.8 year were used in a replicated 4 × 4 Latin Square experiment with a 2 × 2 factorial design during 4 periods of 28 days, including 21 days for dietary adaptation and 7 days for sampling. Horses were offered 1 of 4 treatments: (1) no FOS or 2.5 × 10 colony forming ...
Watson ED.The ability of equine endometrium to release prostaglandin (PG) F, PGE2, and leukotriene (LT) B4 was studied in vitro, using endometrial tissue from diestrous mares. Because of the high cross-reactivity of the PGF antiserum with PGF1 alpha and with PGF2 alpha, results were quoted as total immunoreactive PGF. Significant concentrations of these arachidonate metabolites were released into tissue culture medium between 1 and 24 hours of incubation. Significantly higher concentrations of PGE, but not of PGE2 or LTB4, were released from endometria of mares with chronic endometritis than from genita...
Peroni JF, Borjesson DL.The recent interest in equine stem cell biology and the rapid increase in experimental data highlight the growing attention that this topic has been receiving over the past few years. Within the field of stem cell biology, the relevance of immunobiology is of particular intrigue. It appears that optimal and effective stem cell therapy for equine patients will require a thorough analysis of the immune properties of stem cells as well as their response to immune mediators. The main goal of this review is to discuss the biology of adult mesenchymal stem cells in the context of immunology.
Yates AC, Stewart AA, Byron CR, Pondenis HC, Kaufmann KM, Constable PD.To determine the effects of sodium hyaluronate (HA) in combination with methylprednisolone acetate (MPA) on interleukin-1 (IL-1)-induced inflammation in equine articular cartilage pellets. Methods: Chondrocytes collected from 7 horses euthanatized for problems unrelated to the musculoskeletal system. Methods: Chondrocyte pellets were treated with medium (negative control); medium containing IL-1 (positive control); or medium containing IL-1 with MPA only (0.05 or 0.5 mg/mL), HA only (0.2 or 2 mg/mL), or MPA (0.05 or 0.5 mg/mL) and HA (0.2 or 2 mg/mL) in combination. Proteoglycan (PG) synthesis...
Hamouzová P, Dobešová O, Řeháková K, Stehlíková Š, Čížek P, Drábková Z, Jahn P, Doubek J.This study is the first to provide information on the lymphocyte subpopulations in peritoneal effusions in horses. Peritoneal transudates (n = 12), peritoneal exudates (n = 6) and a pleural exudate (n = 1) were analyzed. The total nucleated cell count (TNCC), total protein (TP) and matrix metalloproteinase-9 (MMP-9) concentration determined by ELISA were measured and routine cytological evaluation was performed. CD3, CD4, CD8 and CD21 positive cells were detected by flow cytometry. A higher percentage of neutrophils (P < 0.05) and higher MMP-9 (P < 0.01) levels were found in ex...
Ramsay JD, Evanoff R, Wilkinson TE, Divers TJ, Knowles DP, Mealey RH.Equine hepacivirus (EHCV; nonprimate hepacivirus) is a hepatotropic member of the Flaviviridae family that infects horses. Although EHCV is the closest known relative to hepatitis C virus (HCV), its complete replication kinetics in vivo have not been described, and direct evidence that it causes hepatitis has been lacking. In this study, we detected EHCV in 2 horses that developed post-transfusion hepatitis. Plasma and serum from these horses were used to experimentally transmit EHCV to 4 young adult Arabian horses, two 1-month-old foals (1 Arabian and 1 Arabian-pony cross), and 2 foals (1 Ara...
Giese M, Bahr U, Jakob NJ, Kehm R, Handermann M, Müller H, Vahlenkamp TH, Spiess C, Schneider TH, Schusse G, Darai G.Equine arteritis virus (EAV) is the causative agent of the equine viral arteritis. It is a small RNA virus with a linear, non-segmented plus RNA genome. EAV is a member of the Arteriviridae family that includes porcine reproductive and respiratory syndrome virus (PRSSV), simian haemorrhagic fever virus (SHFV) and lactate dehydrogenase virus (LDV). The viral transmission is via respiratory and reproductive routes. Clinical signs in horses vary, and severe infection can lead to abortions in pregnant mares or neonatal foal death. The aim of this study was to investigate the development of the imm...
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, ...
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...
Palmer JE, Benson CE, Whitlock RH.Fourteen ponies and 3 horses were inoculated with Ehrlichia risticii 2 to 20 months after a similar initial inoculation. Although all 17 had clinical signs of equine ehrlichial colitis after the first inoculation, 16 of 17 remained clinically normal following the second inoculation. The remaining pony had a transient fever and developed signs of depression. Before the initial inoculation, none of the animals had a detectable antibody titer to E risticii. All animals developed titers after the initial infection; however, a significant change of titer did not develop after reinoculation in most ...
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...
