Leukocytes, also known as white blood cells, are an integral component of the equine immune system, responsible for defending horses against infections and foreign substances. These cells are produced in the bone marrow and circulate throughout the bloodstream and tissues. In horses, leukocytes are categorized into several types, including neutrophils, lymphocytes, monocytes, eosinophils, and basophils, each with specific functions in immune response. Neutrophils are involved in phagocytosis and the destruction of pathogens, while lymphocytes are key players in adaptive immunity. Monocytes differentiate into macrophages and dendritic cells, contributing to pathogen clearance and antigen presentation. Eosinophils and basophils are associated with allergic reactions and parasitic infections. Variations in leukocyte counts and distribution can indicate underlying health conditions, making them valuable in veterinary diagnostics. This page aggregates peer-reviewed research studies and scholarly articles that explore the physiology, function, and diagnostic relevance of leukocytes in equine health.
Ríos DL, López C, Carmona JU.The aims were as follows: (1) to evaluate the effects at 48 and 96 h of two concentrations (25 and 50%) of leukocyte and platelet-rich gel (L-PRG) and pure PRG (P-PRG) supernatants on the production/degradation in normal equine synovial membrane explants (SME) of platelet derived growth factor isoform BB, transforming growth factor beta-1, tumor necrosis factor alpha, interleukin (IL-) 4 (IL-4), IL-1 receptor antagonist (IL-1ra), and hyaluronan (HA) synthesis and (2) to correlate these molecules with their respective PRG supernatant treatments. SME from 6 horses were cultured for 96 h with...
Drebert Z, Golke A, Cymerys J, Słońska A, Chmielewska A, Tucholska A, Bańbura MW.Equid herpesvirus type 1 (EHV-1) is a prevalent causative agent of equine diseases worldwide. After primary replication in the respiratory epithelium the virus disseminates systemically through a peripheral blood mononuclear cell (PBMC)-associated viraemia. EHV-1 is the only alphaherpes- virus known so far which is capable of establishing latent infection not only in neurons but also in immune system cells (mainly in lymphocytes and macrophages). Since leukocytes are not the target cells for viral replication but are used to transport EHV-1 to the internal organs, the questionremains how the v...
Vallone LV, Neaderland MH, Ledbetter EC, Dubielzig RR.To describe clinical, in vivo confocal microscopic, histopathologic, polymerase chain reaction assay for antigen receptor rearrangement (PARR) and immunohistochemical features of a horse with suspected malignant transformation of corneal B lymphocytes in immune-mediated keratitis (IMMK) and to also report surgical management and adjunctive treatment including topical and radiation therapies. Methods: A 15-year-old Oldenburg gelding was examined for presumptive progressive stromal IMMK of the right eye which became refractory to medical management. Corneal in vivo confocal microscopy revealed...
Kol A, Wood JA, Carrade Holt DD, Gillette JA, Bohannon-Worsley LK, Puchalski SM, Walker NJ, Clark KC, Watson JL, Borjesson DL.Intravenous (IV) injection of mesenchymal stem cells (MSCs) is used to treat systemic human diseases and disorders but is not routinely used in equine therapy. In horses, MSCs are isolated primarily from adipose tissue (AT) or bone marrow (BM) and used for treatment of orthopedic injuries through one or more local injections. The objective of this study was to determine the safety and lymphocyte response to multiple allogeneic IV injections of either AT-derived MSCs (AT-MSCs) or BM-derived MSCs (BM-MSCs) to healthy horses. Methods: We injected three doses of 25 × 10(6) allogeneic MSCs fro...
Gajos K, Kozdrowski R, Nowak M, Siemieniuch MJ.Mares that fail to become pregnant after repeated breeding, without showing typical signs of clinical endometritis, should be suspected of subclinical endometritis (SE). Contact with infectious agents results in altered synthesis and secretion of inflammatory mediators, including cytokines and arachidonic acid metabolites, and disturbs endometrial functional balance. To address the hypothesis that SE affects the immune endocrine status of the equine endometrium, spontaneous secretion of prostaglandin E(2) (PGE(2)), prostaglandin F(2α) (PGF(2α)), 6-keto-PGF(1α )(a metabolite of prostacyclin ...
Kravtsov AL.Compare the content of bactericidal granules (BG) in blood phagocytes of animals, that differ by species sensitivity to plague infection, under the conditions of measuring, that ensure automatic differentiating by this parameter of monocytes and granulocytes of human blood. Methods: Human whole blood leukocytes were studied, as well as from 7 animal species: mice, guinea pigs, golden hamsters, white rats, rabbits, dogs and horses. Acridine orange (AO) was used for supra-vital staining in primary (bactericidal) granule cells. Relative BG content was measured in separate cells in conventional un...
Mendoza L, Piquemal D, Lejeune JP, Vander Heyden L, Noguier F, Bruno R, Sandersen C, Serteyn D.Osteochondrosis (OC) is a developmental disease in horses which has a significant impact on the horse's welfare and performance. The early disturbance in the process of endochondral ossification progresses to inflammatory and repair processes in older horses. Previously, differentially expressed genes in leukocytes of OC-affected horses have been identified. The aim of the present study is to detect age-related changes in these differentially expressed genes. Methods: The expression of OC-related genes was analysed by real-time PCR and subsequent statistical analysis (ΔΔCT) in the leukocytes...
Hemberg E, Einarsson S, Kútvölgyi G, Lundeheim N, Bagge E, Båverud V, Jones B, Morrell JM.This study investigated the relationship of the health of the newborn foal and (1) number of polymorphonuclear leukocytes (PMNLs) in the amniotic fluid, (2) bacteria present in the amniotic fluid and the venous umbilical blood, and (3) bacteria present in the uterus of the newly foaled mare. A further aim was to investigate relationships between the bacteriologic findings in the amniotic fluid, umbilical blood, and uterus postpartum. Samples were taken from 50 Standardbred trotter foaling mares from a well-managed stud in Sweden. Parturition was spontaneous in all cases. Length of pregnancy, p...
Schnabel CL, Steinig P, Schuberth HJ, Koy M, Wagner B, Wittig B, Juhls C, Willenbrock S, Murua Escobar H, Jaehnig P, Feige K, Cavalleri JM.Leukocytes and their functional capacities are used extensively as biomarkers in immunological research. Commonly employed indicators concerning leukocytes are as follows: number, composition in blood, response to discrete stimuli, cytokine release, and morphometric characteristics. In order to employ leukocytes as biomarkers for disease and therapeutic monitoring, physiological variations and influencing factors on the parameters measured have to be considered. The aim of this report was to describe the ranges of selected leukocyte parameters in a sample of healthy horses and to analyse wheth...
Nielsen MK, Rubinson EF, Chambers TM, Horohov DW, Wagner B, Betancourt A, Reedy SE, Jacobsen S.Anthelmintics and vaccines are commonly given concurrently in routine equine management, but it is unknown to what extent an interaction between the two exists. Cyathostomins can modulate the local immune response by stimulating a type 2 helper T cell (Th2) response. In addition, anti-inflammatory effects of ivermectin have been found in rodent models. It is unknown whether these anti-inflammatory effects affect the acute phase response elicited by commonly used vaccines. This study evaluated how the acute phase inflammatory response, leukocyte expression of pro-inflammatory cytokines, and vac...
Ramery E, Fraipont A, Richard EA, Art T, Pirottin D, van Delm W, Bureau F, Lekeux P.Inflammatory airway disease (IAD) affects performance and well-being of horses. Diagnosis is primarily reached by bronchoalveolar lavage (BAL) cytology which is invasive and requires sedation. Objective: The purpose of this study was to identify differential gene expression in peripheral blood of horses with IAD using species-specific expression microarrays. Methods: Equine gene expression microarrays were used to investigate global mRNA expression in circulating leukocytes from healthy, IAD-affected, and low-performing Standardbred and endurance horses. Results: Nine genes in Standardbred and...
Janda J, Lehmann M, Luttmann W, Marti E.Interleukin-3 is a growth and differentiation factor for various hematopoietic cells. IL-3 also enhances stimulus-dependent release of mediators and cytokine production by mature basophils. Function of IL-3 has not been studied in horses because of lack of horse-specific reagents. Our aim was to produce recombinant equine IL-3 and test its effect on sulfidoleukotriene and cytokine production by equine peripheral blood leukocytes (PBL). Equine IL-3 was cloned, expressed in E. coli and purified. PBL of 19 healthy and 20 insect bite hypersensitivity (IBH)-affected horses were stimulated with Culi...
Bauquier JR, Tudor E, Bailey SR.Despite the severity and common occurrence of equine endotoxaemia, the available anti-endotoxic treatments do not effectively target key inflammatory mechanisms such as leucocyte activation and cytokine production. In this study, four compounds with potential anti-endotoxic effects, namely rolipram, azithromycin, ethyl pyruvate and metformin, were investigated in vitro using equine whole blood stimulated with bacterial lipopolysaccharide. TNF-α and IL-1β production were measured in plasma. Rolipram was the most potent inhibitor of cytokine production (IC50 0.84 and 4.68 μm for TNF-α and IL...
Passamonti F, Vardi DM, Stefanetti V, Marenzoni ML, Prato S, Cévese P, Coletti M, Pepe M, Casagrande Proietti P, Olea-Popelka F.Early diagnosis and prevention of Rhodococcus equi pneumonia in foals represent important goals for equine clinicians. Recent protocols for diagnosis and treatment of Rhodococcosis in foals typically rely on a multimodal approach based on sonographic evidence suggestive of pyogranulomas, sonographic abscess scores and laboratory findings including plasma fibrinogen concentrations, blood biochemistry testing and platelet and leukocyte counts. The aim of this study was to assess the utility of weekly testing of serum amyloid A (SAA) and plasma fibrinogen concentrations in foals to achieve early ...
Battista JM, Tallmadge RL, Stokol T, Felippe MJ.We investigated how the equine fetus prepares its pre-immune humoral repertoire for an imminent exposure to pathogens in the neonatal period, particularly how the primary hematopoietic organs are equipped to support B cell hematopoiesis and immunoglobulin (Ig) diversity. We demonstrated that the liver and the bone marrow at approximately 100 days of gestation (DG) are active sites of hematopoiesis based on the expression of signature messenger RNA (mRNA) (c-KIT, CD34, IL7R, CXCL12, IRF8, PU.1, PAX5, NOTCH1, GATA1, CEBPA) and protein markers (CD34, CD19, IgM, CD3, CD4, CD5, CD8, CD11b, CD172A)...
Patan-Zugaj B, Gauff FC, Plendl J, Licka TF.To investigate effects of endotoxin on leukocyte activation and infiltration of the laminar tissue in isolated perfused equine limbs. Methods: 10 right forelimbs and 3 left forelimbs collected from 10 healthy adult horses after slaughter at a licensed abattoir. procedures: Isolated right forelimbs were randomly assigned to 2 groups (5 forelimbs/group): perfusion of the distal portion for 10 hours with 80 ng of endotoxin/L and perfusion under the same conditions without endotoxin. After perfusion, samples for immunohistochemical detection of leukocytes (by use of antibodies against calprotectin...
Bazzano M, Giannetto C, Fazio F, Rizzo M, Giudice E, Piccione G.The aim of the study was to assess changes in some haematological parameters of periparturient mares from the last three months of pregnancy until the third week after foaling. The study was carried out on 15 healthy pregnant mares (Group A) and 7 healthy non-pregnant non-lactating mares (Group B). Blood samples were collected by jugular venipuncture into EDTA tubes and tested for Haematocrit (Hct), Red Blood Cell (RBC), Haemoglobin (Hb), Platelets (Plt) and White Blood Cell (WBC). Peripheral blood smears were also performed to assess changes in the leucocyte differential count. Group A showed...
Canisso IF, Ball BA, Cray C, Williams NM, Scoggin KE, Davolli GM, Squires EL, Troedsson MH.Currently, placentitis, an important cause of late pregnancy loss in mares, is diagnosed by clinical signs and ultrasonography. Acute phase proteins (APP) are mainly produced and secreted by the liver in response to acute inflammatory stimuli. We hypothesized that APP are increased in mares with placentitis. Methods: Concentrations of serum amyloid A (SAA), haptoglobin (Hp), fibrinogen (Fb), and white blood cell counts (WBC) were determined in plasma of mares with experimentally induced placentitis and gestationally age-matched control mares. Placentitis was induced via intracervical inoculati...
Hessel LN, Bosch G, van Weeren PR, Ionita JC.Autologous platelet concentrates (APCs) are being used increasingly in horses to enhance regeneration in tissues that have poor natural healing capabilities. Numerous APC systems, which are based on different preparation techniques and were originally developed for human patients, are now routinely used in equine cases. However, preliminary process validation and adequate in vitro biochemical characterisation of most of these systems do not exist for horses. Objective: To compare haematological findings and growth factor concentrations of equine APCs obtained with 4 commercially available syst...
Stirn M, Moritz A, Bauer N.Modern automated haematology instruments are capable of performing leukocyte differentials faster, cheaper and with a higher precision than the traditional 100-cell manual differential count. Thus, in human laboratories, criteria are defined for performing a manual review of the blood smear resulting in a marked reduction of manual differential counts. While common in human laboratories, this approach to reducing the number of manual differentials in veterinary laboratories is still not commonly performed. Thus, our aim was to determine the rate and causes of manual leukocyte differentials in ...
Rapacz-Leonard A, Dąbrowska M, Janowski T.During pregnancy in larger mammals, the maternal immune system must tolerate the fetus for months while resisting external infection. This tolerance is facilitated by immunological communication between the fetus and the mother, which is mediated by Major Histocompatibility Complex I (MHC I) proteins, by leukocytes, and by the cytokines secreted by the leukocytes. Fetal-maternal immunological communication also supports pregnancy by inducing physiological changes in the mother. If the mother "misunderstands" the signal sent by the fetus during pregnancy, the fetus will be miscarried or deliver...
Demyda-Peyrás S, Anaya G, Bugno-Poniewierska M, Pawlina K, Membrillo A, Valera M, Moreno-Millán M.Sex chromosome aberrations are known to cause congenital abnormalities and unexplained infertility in horses. Most of these anomalies remain undiagnosed because of the complexity of the horse karyotype and the lack of specialized laboratories that can perform such diagnoses. On the other hand, the utilization of microsatellite markers is a technique widely spread in horse breeding, mostly because of their usage in parentage tests. We studied the usage of a novel combination of diagnostic approaches in the evaluation of a very uncommon case of chromosomal abnormalities in a Spanish purebred col...
Niwa H, Kato H, Hobo S, Kinoshita Y, Ueno T, Katayama Y, Hariu K, Oku K, Senoh M, Kuroda T, Nakai K.Clostridium difficile is an important cause of acute enterocolitis in horses. We describe five cases of C difficile infection occurring postoperatively in Thoroughbred racehorses. Following diarrhoea or colic accompanied by a marked increase in packed cell volume (to ≥60 per cent) and leucopenia (≤4000 cells/μl) within two to four days after surgery in all five horses, four of them died or were euthanased because of colitis or severe diarrhoea. In these four horses, necrotising entero-typhlo-colitis was revealed by postmortem examination, and C difficile was recovered from the contents of...
Mariella J, Pirrone A, Gentilini F, Castagnetti C.The purposes of this study were to determine physiological changes occurring in hematologic and biochemical parameters in mares between the last month of gestation and the first week after parturition. If a significant change was observed with respect to the reference interval of an adult horse, a further aim of the study was to establish different reference intervals. Blood samples were collected from 62 healthy pregnant Standardbred mares. Seventeen nonpregnant and nonlactating mares were used as a control group. In pregnant mares, blood sampling was conducted every three days from 1 month b...
Degroote RL, Hauck SM, Treutlein G, Amann B, Fröhlich KJ, Kremmer E, Merl J, Stangassinger M, Ueffing M, Deeg CA.Autoimmune uveitis is characterized by crossing of blood-retinal barrier (BRB) by autoaggressive immune cells. Equine recurrent uveitis (ERU) is a valuable spontaneous model for autoimmune uveitis and analyses of differentially expressed proteins in ERU unraveled changed protein clusters in target tissues and immune system. Healthy eyes are devoid of leukocytes. In ERU, however, leukocytes enter the inner eye and subsequently destroy it. Molecular mechanisms enabling cell migration through BRB still remain elusive. Previously, we detected decreased talin 1 expression in blood-derived granulocy...
Hemberg E, Einarsson S, Jones B, Mikko S.The objective of this study was to investigate the presence and origin of polymorphonuclear leucocytes (PMNLs) in the amniotic fluid of mares giving birth to healthy foals. Material from 25 mares was included. Amniotic fluid was collected during parturition before breakage of the amniotic vesicle. Manual microscopic cytologic evaluation was made on cytospin preparations after staining. PMNLs were found in all amniotic samples examined. The genomic DNA was extracted from 12 of the amniotic fluid samples and was genotyped. The results indicate that the PMNLs originate from the foetus.
Salciccia A, Sandersen C, Grulke S, de la Rebière de Pouyade G, Caudron I, Serteyn D, Detilleux J.The objectives of this study were to describe and relate perioperative changes in blood leukocyte counts to the outcome of surgical colic horses, determine a cut-off value in the early postoperative period to obtain an indicator of the outcome, and compare the obtained value to a validation population of horses. Fifty-three horses undergoing colic surgery were included in the descriptive part of the study. Total leukocyte counts were performed before, during and serially after surgery. A receiver operating characteristic analysis was performed on the leukocyte counts of 45 of these horses to d...
Vairo S, Favoreel H, Scagliarini A, Nauwynck H.Currently, little is known on the cellular pathogenesis of equine arteritis virus (EAV). The purpose of the present study was to identify the target cells in ponies experimentally inoculated with EAV 08P178 (EU, clade-1). EAV-target organs (respiratory tissues with associated lymphoid tissues and large intestines), collected at 3 and 7 days post inoculation (dpi) and with virus titers≥10(5.0) TCID50/g, were processed with double immunofluorescence staining for the simultaneous detection of EAV N-protein and one of the following cell markers: CD172a (myeloid cells), CD3 (T lymphocytes), IgM (...
Cian F, Tyner G, Martini V, Comazzi S, Archer J.A 16-year-old, Irish Draft mare was admitted to the referring veterinarian for an annual health check. A mild generalized lymphadenomegaly was noted. Rectal palpation and transrectal ultrasonographic examination revealed prominent mesenteric lymph nodes. A transcutaneous abdominal ultrasonographic evaluation was unremarkable. A CBC revealed a marked leukocytosis (63.06 × 10(3)/μL) and lymphocytosis (58.2 × 10(3)/μL) due to increased numbers of small lymphocytes. No evidence of anemia or thrombocytopenia was found and neutrophil counts were low-normal. Cytologic examination of fine-needle a...
Sarmiento J, Perez B, Morales N, Henriquez C, Vidal L, Folch H, Galecio JS, Morán G.A reduction in inflammatory cell apoptosis is an important concept in the maintenance of inflammation and a potential target for the resolution of inflammation in many inflammatory diseases. Dysregulation of apoptosis has been implicated in a range of diseases, including tumors, neurodegenerative disorders and autoimmunity, and may also be implicated in allergic asthma. In horses, recurrent airway obstruction (RAO) is an asthma-like condition that is characterized increased survival neutrophil bronchial. Tamoxifen is a synthetic, non-steroidal, anti-estrogen agent that is widely used for treat...
Vinther AM, Skovgaard K, Heegaard PM, Andersen PH.In horses, insights into the innate immune processes in acute systemic inflammation are limited even though these processes may be highly important for future diagnostic and therapeutic advances in high-mortality disease conditions as the systemic inflammatory response syndrome (SIRS) and sepsis. Therefore, the aim of this study was to investigate the expression of 31 selected blood leukocyte immune genes in an equine model of acute systemic inflammation to identify significantly regulated genes and to describe their expression dynamics during a 24-h experimental period. Systemic inflammation ...
Smith DJ, Iqbal J, Purewal A, Hamblin AS, Edington N.IL-2 and equine chorionic gonadotrophin (eCG) initiated reactivation of equid herpesvirus-1 (EHV-1) from venous lymphocytes at a frequency of 1/10(-5). Indirect immunofluorescence showed that > 80% of virus-positive leukocytes were CD5+/CD8+ with the remaining 20% being CD5+/CD8-/CD4-. Cocultivation demonstrated that the reactivated virus was infectious. In addition, virus was reactivated in vitro from leukocytes of > 70% of horses by the mitogens phytohaemagglutinin (PHA) and pokeweed mitogen (PWM). Transfer of supernatants showed that IL-2 and eCG acted indirectly by causing the releas...
Durando MM, MacKay RJ, Linda S, Skelley LA.Polymyxin B and an antiserum against an Re mutant Salmonella typhimurium were evaluated for protective effect in an equine model endotoxemia. Six 3- to 5-month-old foals were given endotoxin (0.25 micrograms/kg of body weight) IV after no pretreatment, or pretreatment with polymyxin B (6,000 U/kg, IV) or S typhimurium antiserum (1.5 ml/kg, IV). When given without pretreatment, endotoxin caused transient recumbency and increases in rectal temperature, and heart and respiratory rates. In addition, leukopenia and increases in circulating tumor necrosis factor (TNF) and interleukin 6 (IL-6) activi...
Bullido R, Doménech N, Alvarez B, Alonso F, Babín M, Ezquerra A, Ortuño E, Domínguez J.A set of five monoclonal antibodies (mAb) against porcine major histocompatibility complex (MHC), or swine leukocyte antigens (SLA), class II molecules has been characterized. These mAbs appear to recognize monomorphic determinants on SLA-DR (2F4, 1F12 and 2E9/13) and SLA-DQ (BL2H5 and BL4H2) molecules, as assessed by flow cytometry and immunoprecipitation. By Western blot, the 2F4, 1F12, BL2H5 and BL4H2 epitopes were located on the beta-chains of these molecules. mAbs 2F4 and 1F12 crossreact with leucocytes of dog, cattle, horse and human; mAbs 2E9/13, BL2H5 and BL4H2 bind leucocytes of cattl...
Ibrahim S, Steinbach F.Earlier studies investigating the cross-reactivity of antibodies submitted to the HLDA8 had used flow cytometry as a method of choice to screen mAbs for reactivity with equine leukocytes, including two-color flow-cytometry to characterize the lymphocyte population they detect. In addition, immuno-histochemistry (IHC) was used to detect distribution of positive cells in lymphoid tissue sections. In this study we performed immunoprecipitation (IP) to complement the previous results and add valuable information regarding the molecules detected by the cross-reacting antibodies. Surface molecules f...
Arai T, Inoue A, Uematsu Y, Sako T, Kimura N.The activities of the enzymes involved in the malate-aspartate shuttle and lactate dehydrogenase (LDH) and the pattern of the isoenzymes of LDH were determined in plasma and peripheral leukocytes of lactating Holstein cows and thoroughbred riding horses as representative herbivorous animals. In the horse plasma, LDH activities were significantly lower and AST activities were significantly higher than those in the cow plasma. The specific activities of cytosolic malate dehydrogenase (MDH), LDH and AST in the horse leukocytes were higher than those in the cows. The cytosolic ratio of MDH/LDH act...
Dubin A, Koj A, Chudzik J.Cytoplasmic granules were isolated from horse blood polymorphonuclear leucocytes by the heparin method and extracted with 0.9% NaCl by repeated freezing. Soluble proteins were separated on a column of Sephadex G-75 followed by chromatography on a column of CM-Sephadex with a NaCl gradient. Gel filtration, density-gradient centrifugation, isoelectric focusing and 0.1% sodium dodecyl sulphate/polyacrylamide-gel electrophoresis at pH 7.0 and at pH 4.5 were used to determine molecular parameters of proteinases. Three enzymes hydrolysing both casein and N-benzyloxycarbonyl-L-alanine nitrophenyl est...
Hart KA, Barton MH, Vandenplas ML, Hurley DJ.Low-dose hydrocortisone (LDHC) therapy modulates inflammatory responses in adults and improves outcomes in some septic adults and neonates, but its immunologic effects have not been evaluated in neonates. The objective of this study was to evaluate effects of LDHC therapy on ex vivo immune function in neonatal horses (foals). We hypothesized that LDHC treatment would dampen proinflammatory responses without impairing neutrophil function. Hydrocortisone (1.3 mg/kg/d i.v.) was administered to foals in a tapering 3.5 d course. Peripheral blood leukocytes were collected from foals before, during, ...
Lucassen A, Finkler-Schade C, Schuberth HJ. () fermentation products (SCFP) are used in animal husbandry as pre- and postbiotic feed supplements. A variety of immunomodulatory effects are noted in many species. The purpose of this study was to test the hypothesis that horses fed with SCFP containing feed additive Olimond BB display a modulated early immune response after influenza vaccination. Six horses received Olimond BB pellets (OLI) and five horses were fed placebo pellets (PLA) for 56 days. On day 40 all horses were vaccinated with a recombinant influenza A/equi-2 vaccine. At the day of vaccination, the groups did not differ in t...
Anton F, Morales C, Aguilar R, Bellido C, Aguilar E, Gaytán F.The existence of a physiological integration between the immune and endocrine systems has long been recognized. In spite of the abundant literature data on the presence of cells of the immune system in the testis, mast cells and eosinophil leukocytes have received little attention. We have studied the presence, distribution and numbers of mast cells and eosinophils in the testes of 12 mammalian species. Mast cells were frequently found in equine (stallion, ass and mule) and human testis, whereas eosinophils were nearly absent. On the contrary, eosinophils were abundant in the hare testis, whil...
Fairbairn SM, Page CP, Lees P, Cunningham FM.Previous studies have shown that bronchoalveolar lavage fluid from horses with allergic respiratory disease and showing clinical symptoms contains increased numbers of neutrophils. In some cases, the eosinophil count is also increased. In this study the time course of changes in lung function and the accumulation of radiolabelled leucocytes and platelets in the lungs of allergic and normal horses has been examined during a 7 hr allergen exposure. Antigen challenge had no effect on pleural pressure or the distribution of radiolabelled neutrophils, eosinophils or platelets in normal horses. In c...
Davis JL, Salmon JH, Papich MG.To determine the pharmacokinetics of itraconazole after IV or oral administration of a solution or capsules to horses and to examine disposition of itraconazole in the interstitial fluid (ISF), aqueous humor, and polymorphonuclear leukocytes after oral administration of the solution. Methods: 6 healthy horses. Methods: Horses were administered itraconazole solution (5 mg/kg) by nasogastric tube, and samples of plasma, ISF, aqueous humor, and leukocytes were obtained. Horses were then administered itraconazole capsules (5 mg/kg), and plasma was obtained. Three horses were administered itraconaz...
Hall JA, Van Saun RJ, Wander RC.The study objective was to determine the effect of feeding corn oil or fish oil to horses on plasma fatty acid profiles and leukotriene B (LTB) synthesis by stimulated peripheral blood neutrophils. Two groups of horses (n = 5) were randomly assigned to diets supplemented with either 3.0% (by weight) corn oil or fish oil for a period of 14 weeks. The ratio of (n-6) to (n-3) fatty acids in oil supplements was 68.1:1 for corn oil and 0.12:1 for fish oil. Production of LTB4 and LTB, by peripheral blood neutrophils stimulated with calcium ionophore A23187 and plasma cholesterol, triacylglycerol, an...
Wilmink JM, van Weeren PR.Second-intention repair is faster in ponies than in horses and faster in body wounds than in limb wounds. To a large extent, the differences between horses and ponies can be explained by differences in the local inflammatory response, which are a result of the functional capacity of leukocytes. In ponies, leukocytes produce more inflammatory mediators,resulting in better local defense, faster cellular debridement, and a faster transition to the repair phases, with more wound contraction. In horses,leukocytes produce fewer mediators, initiating a weak inflammatory response, which becomes chroni...
Cooper CJ, Keller SM, Arroyo LG, Hewson J, Kenney D, Bienzle D.Leukemia is broadly divided into acute and chronic lymphocytic and myeloid types based on the proportion of blasts, morphology of cells, and expression of specific antigens on neoplastic cells. Classifying leukemia in horses can be challenging if blasts predominate and since few antibodies to identify cell types are available. The objective of this study was to describe in detail the clinical and pathologic features of acute leukemia in horses. Twelve horses ranging from 0.2 to 25.9 years of age were diagnosed with acute leukemia. Six cases were classified as acute lymphocytic leukemia (ALL) b...
Ríos DL, López C, Carmona JU.The aims were as follows: (1) to evaluate the effects at 48 and 96 h of two concentrations (25 and 50%) of leukocyte and platelet-rich gel (L-PRG) and pure PRG (P-PRG) supernatants on the production/degradation in normal equine synovial membrane explants (SME) of platelet derived growth factor isoform BB, transforming growth factor beta-1, tumor necrosis factor alpha, interleukin (IL-) 4 (IL-4), IL-1 receptor antagonist (IL-1ra), and hyaluronan (HA) synthesis and (2) to correlate these molecules with their respective PRG supernatant treatments. SME from 6 horses were cultured for 96 h with...
Jiménez-Aristazábal RF, Carmona JU, Prades M.The aims of the present study were (1) to describe the microscopic and ultrastructural appearance of equine platelet-rich fibrin (PRF) clots and (2) to determine the release and degradation of transforming growth factor beta 1 (TGF-β) and insulin-like growth factor type I (IGF-I) from PRF clots incubated over 14 days. Whole blood from six horses was collected into plain tubes and centrifuged at 240 g for 8 minutes. Clots were evaluated by histology and by both transmission and scanning electronic microscopy (TEM and SEM). Growth factor concentrations were measured by ELISA at 48-hour inter...
Forbes G, Church S, Savage CJ, Bailey SR.Endotoxaemia is a major cause of equine morbidity, and plasma from horses immunised against Escherichia coli is used in its treatment. The aim of this study was to determine the effects of hyperimmune plasma on the clinical and leukocyte responses, including production and activity of TNFα, in an in vivo endotoxin challenge model. Pre-treatment with hyperimmune equine plasma had no significant effect on peak total plasma TNFα concentration (occurring 90min after the administration of 30ng/kg LPS). However, the bioavailable (unbound) TNFα measured by bioassay was significantly reduced in pla...
Garrett KS, Bramlage LR, Spike-Pierce DL, Cohen ND.To determine the effects of treatment with platelet- and leukocyte-rich plasma (PRP) on future 2-, 3-, and 4-year-old racing performance of yearling Thoroughbreds with proximal sesamoid bone inflammation and associated suspensory ligament branch (SLB) desmitis. Methods: Randomized clinical trial. Methods: 39 yearling Thoroughbreds. Methods: Yearling Thoroughbreds with radiographic evidence of performance-limiting proximal sesamoid bone inflammation and ultrasonographic evidence of associated SLB desmitis were identified and randomly assigned to undergo PRP (treatment group) or saline (0.9% NaC...
Malinowski K, Shock EJ, Rochelle P, Kearns CF, Guirnalda PD, McKeever KH.Ageing appears to affect immune and neuroendocirne function in horses and response to acute exercise. No studies have examined the combined effects of training and ageing on immune and neuroendocirne function in horses. Objective: To ascertain whether training and age would affect the plasma beta-endorphin (BE) and cortisol (C) as well as immune function responses to acute exercise in Standardbred mares. Methods: Graded exercise tests (GXT) and simulated race tests (SRT) were performed before and after 12 weeks training at 60 % HRmax. BE and C were measured at rest and at 5, 10, 20, 40, 60 and...
Lunn DP, Holmes MA, Duffus WP.This paper describes the characteristics of a monoclonal antibody (CVS10) that reacts with an equine leukocyte antigen. On the basis of tissue distribution and biochemical characteristics, this antigen is equine MHC II. The equine MHC II antigen was found on a large subset of T-lymphocytes in addition to all B-lymphocytes, as has been reported previously. In addition MHC II was found to be present on a large proportion of both the mutually exclusive equine T-lymphocyte subpopulations which express either the equine homologues of CD4, or CD8. In a study of changes in equine MHC II expression wi...
Battista JM, Tallmadge RL, Stokol T, Felippe MJ.We investigated how the equine fetus prepares its pre-immune humoral repertoire for an imminent exposure to pathogens in the neonatal period, particularly how the primary hematopoietic organs are equipped to support B cell hematopoiesis and immunoglobulin (Ig) diversity. We demonstrated that the liver and the bone marrow at approximately 100 days of gestation (DG) are active sites of hematopoiesis based on the expression of signature messenger RNA (mRNA) (c-KIT, CD34, IL7R, CXCL12, IRF8, PU.1, PAX5, NOTCH1, GATA1, CEBPA) and protein markers (CD34, CD19, IgM, CD3, CD4, CD5, CD8, CD11b, CD172A)...
Higgins AJ, Lees P, Sedgwick AD.Two experimental models of acute non-immune inflammation have been developed to enable studies of the biochemical composition and cellular content of exudates to be undertaken. Both are based on the creation of a mild, reproducible and reversible inflammatory reaction, which is free from uncontrolled incidental factors and which causes minimal distress to the experimental animals. The polyester sponge model involves the insertion of small polyester sponge strips soaked in sterile carrageenan solution into subcutaneous neck pouches and their serial removal. The tissue-cage model is based on the...
Katila T.The uterus of domestic animals, including the horse, has a dual role in the interaction of the uterus and sperm. On one hand, uterine contractions carry sperm toward the oviduct, and on the other hand the uterus eliminates excessive sperm. The selection of sperm for the small numbers of "good" cells that gain access to the oviduct and for the majority of sperm that will be destroyed takes place in the uterus. The sperm-uterine interaction works both ways; sperm and seminal plasma also have several effects on the uterus. Sperm and seminal plasma probably provoke uterine contractions. Sperm indu...
Lavoie JP, Fiset L, Laverty S.A retrospective study of 40 horses with primary lung abscesses without pleuropneumonia showed that lung abscesses occurred predominantly in young horses, usually in foals aged < or = 6 months. Hyperfibrinogenaemia was present in all but 2 horses, and other common clinical and haematological findings were hyperthermia, tachycardia, polypnoea, and neutrophilic leucocytosis. The most common bacterial species isolated from transtracheal aspirates were Streptococcus zooepidemicus (20/34) and Rhodococcus equi (13/34). Most horses (23/27) discharged from the hospital were long term survivors. Of t...
Evans KS, Carpenter SL, Sevoian M.The enzyme-linked immunosorbent assay (ELISA) antigen-positive and agar-gel immunodiffusion test (AGID)-negative horses do not have infective equine infectious anemia (EIA) virus. The ELISA testing of horse leukocyte culture (HLC) supernatants did detect EIA virus in a HLC that was infected with the Wyoming strain of EIA virus and in HLC derived from horses in febrile, acute, or subacute stages of EIA infection. In supernatants of HLC derived from chronic and inapparent carrier horses, EIA virus was not detected with ELISA. Direct fluorescent antibody tests detected EIA virus in HLC infected w...
Ushimi C, Henson JB, Gorham JR.Primary horse leukocyte cultures were inoculated with 2 or 10 50% tissue culture infective doses (TCID(50)) of equine infectious anemia (EIA) virus per cell, and the titer of cell-associated and fluid-phase virus was determined from 1 to 72 hr postinoculation (PI). Cover slips were collected from 4 to 72 hr PI and stained for EIA viral antigen by the indirect immunofluorescent (FA) technique. Viral replication was detected after a latent period of approximately 18 to 24 hr and reached peak titers of approximately 10(4.5) to 10(6) TCID(50)/0.5 ml from 48 to 72 hr PI. The fluid phase contained 1...
Cook VL, Neuder LE, Blikslager AT, Jones SL.The effect of lidocaine on in vitro migration and adhesion of equine neutrophils was evaluated. Neutrophils were isolated from equine whole blood using a Percoll-gradient centrifugation protocol. Purified neutrophils were incubated with lidocaine at concentrations from 0.1 to 1000 microg/ml for 30 min at 37 degrees C, after calcein loading. Neutrophil integrin-mediated adhesion in response to stimulation with 100 nM LTB(4), 100 nM PAF, or 100 ng/ml IL-8, or integrin-mediated migration in response to stimulation with 100 nM LTB(4), 150 nM PAF, or 100 ng/ml IL-8 was assessed. Statistical signifi...
