Neutrophils are a type of white blood cell that play a significant role in the immune system of horses. They are involved in the body's defense mechanisms against infections and are typically one of the first responders to microbial invasion or tissue damage. Neutrophils function by engulfing and destroying pathogens through processes such as phagocytosis and the release of antimicrobial substances. In horses, the number and activity of neutrophils can be indicative of immune status and are often assessed in the context of infectious diseases, inflammation, and other health conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the function, regulation, and clinical implications of neutrophils in equine health.
Boger BL, Manfredi JM, Yob C, Weber PSD, Jacobs CC.Diagnosis of equine septic arthritis is not straightforward, and increasing time between onset, diagnosis, and treatment can have serious consequences for quality of life. Defensins are used in diagnosis of human joint infection. The presence of beta defensins (BDs) in equine synovial fluid and their utility as a biomarker of sepsis has not been investigated; therefore, our objectives were to (1) compare in vitro gene expression of lipopolysaccharide (LPS)-stimulated equine neutrophils to unstimulated neutrophils and (2) compare BD protein expression from normal, aseptically inflamed, and sept...
Janssen P, Tosi I, Hego A, Maréchal P, Marichal T, Radermecker C.Asthma encompasses a spectrum of heterogenous immune-mediated respiratory disorders sharing a similar clinical pattern characterized by cough, wheeze and exercise intolerance. In horses, equine asthma can be subdivided into severe or moderate asthma according to clinical symptoms and the extent of airway neutrophilic inflammation. While severe asthmatic horses are characterized by an elevated neutrophilic inflammation of the lower airways, cough, dyspnea at rest and high mucus secretion, horses with moderate asthma show a milder neutrophilic inflammation, exhibit intolerance to exercise but no...
Protection against infectious diseases can be obtained with vaccines generating immunogenic response through a combination of humoral and cellular immunity. In this study haematological and serum protein electrophoretic profiles of horses vaccinated against herpesvirus 1 (EHV-1) and 4 (EHV-4) were evaluated. Blood samples were collected from 16 horses before (T0), after 24h, 48h, 72h, 1st week, 2nd week and 3rd week (T1I, T2I, T3I, T7I, T14I and T21I) from the first EHV vaccine-dose administration as well as before (TPRE), and after 24h, 48h, 72h, 1st week, 2nd week, 3rd week and 4th week (T1I...
Winther MF, Haugaard SL, Pihl TH, Jacobsen S.Neutrophil gelatinase-associated lipocalin (NGAL) is produced in response to inflammation in horses, but it has not yet been investigated as a biomarker in horses with the abdominal disease. Objective: To investigate NGAL in serum and peritoneal fluid in horses with the abdominal disease. Methods: Retrospective clinical study. Methods: Data from medical records of 270 horses admitted with acute abdominal disease (simple obstructions [n = 43], strangulating obstructions [n = 104], inflammatory abdominal disease [n = 99], non-strangulating intestinal infarction [NSII, n = 24]) and 9 heal...
Bayless RL, Sheats MK, Jones SL.Neutrophils play a major role in many equine conditions, including equine asthma, laminitis, and intestinal ischemia and reperfusion injury, and therefore represent an attractive target for innovative therapeutic approaches. Novel strategies for reducing neutrophilic inflammation include modulation of neutrophil functions and lifespan. Withaferin A (WFA) is a phytochemical with well-established and anti-inflammatory properties, but its direct effects on neutrophils are largely unknown. We hypothesized that WFA would inhibit adhesion, migration, and respiratory burst by equine neutrophils and...
Zandoná Meleiro MC, de Carvalho HJC, Ribeiro RR, da Silva MD, Salles Gomes CM, Miglino MA, de Santis Prada IL.Racehorses are constantly exposed to stress. Aiming to verify the state of blood components and cortisol alterations during their routine and after races, phagocytosis and oxidative neutrophil burst assays, serum cortisol determination, erythrocytes apoptosis evaluation, lymphoproliferation assays, and blood count tests were performed in thirty Thoroughbred racehorses, which were divided in two groups. The samples were taken right after races (moment 0 d), during rest periods (-11 d, +1 d, +3 d), and after training (-8, +2, +5). In both groups, the phagocytosis showed a decrease in percentage ...
Journal of proteomicsMarch 26, 2022
Volume 261 104571 doi: 10.1016/j.jprot.2022.104571
Koziy RV, Bracamonte JL, Yoshimura S, Chumala P, Simko E, Katselis GS.Septic arthritis (SA) is a life-threatening condition in horses, and identifying eradication of infection in equine SA is challenging. This study explored the discovery of putative biomarkers for the eradication of joint infection in horses. We performed proteomics analysis of synovial fluid (SF) and plasma from horses with experimental SA, non-septic lipopolysaccharide-induced arthritis, and controls. The point of eradication of infection in horses with SA was determined previously. We compared spectral intensities between groups as well as before and after the eradication of infection. Twent...
Lee GKC, Kang H, Beeler-Marfisi J, Sears W, Lillie BN, Bienzle D.Salivary scavenger and agglutinin (SALSA) is a secreted protein with various immunomodulatory roles. In humans, the protein agglutinates and inactivates microorganisms, and inhibits the release of pro-inflammatory cytokines. Saliva, which is rich in SALSA, accelerates bacterial phagocytosis, but SALSA's contribution is unclear. In horses, the functions of SALSA in inflammation remain undetermined, so they were investigated through phagocytosis and cytokine assays. Equine SALSA was purified from duodenal tissue, which contains abundant SALSA. To assess phagocytosis, fluorescently-labelled bacte...
Storms N, Medina Torres C, Franck T, Sole Guitart A, de la Rebière G, Serteyn D.Laminitis is a pathology of the equine digit leading to a failure of the dermo-epidermal interface. Neutrophil activation is recognized as a major factor in SIRS-associated laminitis. Less is known about the role of neutrophil activation in laminitis associated with metabolic disorders. The aim of this descriptive study was to observe whether myeloperoxidase is increased in the laminae during early stage laminitis in three horses subjected to a prolonged euglycemic hyperinsulinemic clamp (pEHC). After 48 h of pEHC-treatment, horses were subjected to euthanasia. Two healthy horses are used as c...
Krumrych W, Danek J, Markiewicz H, Gołyński M.The aim of this study was to analyze the chemiluminescence (CL) of peripheral blood in clinically healthy horses of different sexes and ages. The tests were carried out on 119 half- -breed horses, representing various forms of use (66 recreational horses and 53 sport horses). The test material was peripheral blood, which was collected under resting conditions, i.e. before physical activity related to the use of these animals. In the blood samples, spontaneous and stimulated CL with zymosan and phorbol myristate acetate were determined. It has been found that regular training effort increases t...
Ávila ACA, Diniz NC, Serpa RT, Chaves MMBC, Viu MAO, de Oliveira RA.Endometritis is defined as inflammation of the endometrium that may be acute or chronic, infectious, or non-infectious. Endometritis is an important cause of subfertility in mares. Considering the antimicrobial characteristics, immune-stimulating ability, and low cost of ozone (O3) therapy, we aimed to evaluate the effectiveness of intrauterine O3 therapy as an alternative treatment for endometritis in mares. Twenty-five mares with a known reproductive history of uterine infection and inflammation were allocated into three groups: Group 1 (control; n = 7), uterine lavage with Ringer's lactat...
Fingerhut L, Yücel L, Strutzberg-Minder K, von Köckritz-Blickwede M, Ohnesorge B, de Buhr N.Equine recurrent uveitis (ERU) is a common ocular disease of horses and described as a model for human autoimmune uveitis. This immune-mediated, inflammatory condition progressively destroys the eye, ultimately leading to blindness. Genetic and autoimmune factors, next to infections with Leptospira, are discussed as key factors in the pathogenesis. Furthermore, a release of neutrophil extracellular traps (NETs) by activated neutrophils is involved. NETs are composed of decondensed chromatin and proteins that can immobilize invading pathogens. However, if NETs accumulate, they can contribute to...
Niikura T, Tsogtgerel M, Niikura C, Wada H, Kanzawa S, Fujiwara T, Nambo Y.The objective of this study was to examine the effect of prostaglandin F2α (dinoprost) and oxytocin administration on uterine polymorphonuclear neutrophil counts in the Japanese heavy draft mare. To compare polymorphonuclear neutrophil (PMN) counts in the endometrium, a total of 162 samples were collected from 54 estruses of 47 mares (before ovulation, day 0, and day 2) using a double-guarded cytology brush. Dinoprost (PG; 5 mg) was administered intramuscularly (i.m.) only once, on day 0, whereas oxytocin (OT; 20 U i.m.) was administered three times at 12-hr intervals starting on day 0. The p...
Mönki J, Saastamoinen M, Karikoski N, Norring M, Rajamäki M, Mykkänen A.The effects of bedding material on air quality are important amongst horses worldwide. Respiratory diseases, especially equine asthma, are highly prevalent with air hygiene playing a major role on the pathophysiology of these diseases. The objective of our study was to investigate the effects of four bedding materials on the respiratory signs, tracheal mucus score, and tracheal wash (TW) and bronchoalveolar lavage fluid (BALF) cytology in healthy adult horses. The study design was a prospective controlled cross-over study, and the subjects were healthy adult riding school horses ( = 32) from a...
Lee GKC, Beeler-Marfisi J, Viel L, Piché É, Kang H, Sears W, Bienzle D.Horses with severe equine asthma (SEA), also known as heaves and recurrent airway obstruction, have persistent neutrophilic inflammation of the lower airways. Cytologic evaluation of bronchoalveolar lavage (BAL) fluid is commonly used to confirm the clinical diagnosis of SEA. However, the utility of microscopic assessment of bronchial brushings, endobronchial biopsies, and immunohistochemical detection of disease-associated biomarkers for the diagnosis of SEA remain poorly characterized. Salivary scavenger and agglutinin (SALSA) has anti-inflammatory properties and downregulated gene expressio...
Olave CJ, Ivester KM, Couëtil LL, Franco-Marmolejo J, Mukhopadhyay A, Robinson JP, Park JH.To investigate the role of omega-3 polyunsaturated fatty acids (Ω-3)-derived proresolving lipid mediators (PRLM) in the resolution of mild airway inflammation in horses. Methods: 20 horses with mild airway inflammation. Methods: Horses previously eating hay were fed hay pellets (low Ω-3 content; n = 10) or haylage (high Ω-3 content; 9) for 6 weeks. Dust exposure was measured in the breathing zone with a real-time particulate monitor. Bronchoalveolar lavage (BAL) was performed at baseline, week 3, and week 6. The effect of PRLM on neutrophil apoptosis and efferocytosis was examined in vitro....
Mild-moderate (MEA), severe (SEA) equine asthma and exercise-induced pulmonary hemorrhage (EIPH) are common respiratory disorders in horses. The present retrospective study aims to evaluate the role of ultrasonography and endoscopy in the diagnosis of these conditions. Three hundred and three horses were included and divided into SEA, MEA and MEA + EIPH groups, on the basis of history, clinical examination and bronchoalveolar lavage fluid (BALf) cytology; scores were assigned to lung ultrasonography, pharyngeal lymphoid hyperplasia (PLH), tracheal mucus (TM) and tracheal bifurcation edema (TB)...
Amaral A, Fernandes C, Szóstek-Mioduchowska A, Lukasik K, Rebordão MR, Pinto-Bravo P, Skarzynski DJ, Ferreira-Dias G.Cathepsin G (CAT) is a protease released by neutrophils when forming neutrophil extracellular traps that was already associated with inducing type I collagen (COL1) in equine endometrium in vitro. Endometrosis is a fibrotic condition mainly characterized by COL1 deposition in the equine endometrium. The objective was to evaluate if noscapine (an alkaloid for cough treatment with anti-neoplastic and anti-fibrotic properties) would reduce transcription (evaluated by qPCR) and COL1 protein relative abundance (evaluated by western blot) induced by CAT in equine endometrial explants from follicula...
Kang H, Bienzle D, Lee GKC, Piché É, Viel L, Odemuyiwa SO, Beeler-Marfisi J.Severe equine asthma (SEA) is a common, debilitating lower airway inflammatory disorder of older horses. Alveolar macrophages (AMs) survey inhaled particulates from barn sources causing them to switch from an anti-inflammatory to a proinflammatory phenotype, resulting in neutrophil recruitment to the lung. This proinflammatory switch may contribute to the development and prolongation of SEA. Validated antibodies to identify the cells involved in the pathogenesis of SEA are lacking. In this study, monoclonal antibodies against CD90, CD163, and CD206 were tested for reactivity with equine leukoc...
Barton AK, Gehlen H.The term remodeling describes the process resulting in a tissue that is structurally and architecturally altered compared to its healthy counterpart. At least in severe equine asthma, this occurs mainly, but not exclusively, as a consequence of neutrophilic airway inflammation and is characterized by hypertrophy of the smooth muscle layers in airway and arterial walls as well as fibrosis of the bronchial walls and pulmonary interstitial tissue. To date, much less is known for mild to moderate equine asthma. For a long time it was assumed that these processes are irreversible, and at least for ...
Yánez-Ortiz I, Catalán J, Mateo-Otero Y, Dordas-Perpinyà M, Gacem S, Yeste N, Bassols A, Yeste M, Miró J.Jenny shows a large endometrial reaction after semen influx to the uterus with a large amount of polymorphonuclear neutrophils (PMN) migrating into the uterine lumen. PMN act as a sperm selection mechanism through phagocytosis and NETosis (DNA extrudes and, together with proteins, trap spermatozoa). While a reduced percentage of spermatozoa are phagocytosed by PMN, most are found to be attached to neutrophil extracellular traps (NETs). This selection process together with sperm metabolism produces a large amount of reactive oxygen species (ROS) that influence the reproductive success. The pres...
Herteman N, Grimes C, Lavoie JP.To investigate indicators of neutrophil activation in the blood of healthy and asthma-affected horses and assess associations between corticosteroid treatment and these variables. Methods: 48 horses (14 with severe equine asthma [SEA], 21 with mild to moderate equine asthma [MEA], and 13 healthy controls). Methods: In a 3-part retrospective study, hematology analyzer data for horses included in previous studies were reviewed. Neutrophil size, neutrophil light absorbance (NLA), and myeloperoxidase (MPO) index were recorded. Data for each variable were compared among groups for the entire study ...
Rocchigiani G, Ricci E, Navarro MA, Samol MA, Uzal FA.Healthy horses and other animals have large numbers of resident leukocytes in the intestinal wall, but there is scant information regarding which and how many leukocytes are normally present in the equine intestinal wall. Our aim was to provide a reference range of leukocytes in the intestinal mucosal and submucosal propria of normal horses. We included in our study intestinal tissues from 22 Thoroughbred racehorses with no clinical intestinal disease, which had been euthanized because of catastrophic musculoskeletal injuries. Neutrophils, lymphocytes, eosinophils, macrophages, and plasma cell...
Mouithys-Mickalad A, Storms N, Franck T, Ceusters J, de la Rebière de Pouyade G, Deby-Dupont G, Serteyn D.Experimental laminitis, characterized by a failure of the dermal-epidermal interface of the foot, can be induced in horses by the oral administration of a black walnut extract (BWE). In the early phase of this severe and painful disease, an activation of neutrophil occurs, with the release of myeloperoxidase (MPO), a pro-oxidant enzyme of neutrophils, in plasma, skin, and laminar tissue. Juglone, a naphthoquinone derivative endowed with redox properties, is found in walnuts and has been incriminated in this neutrophil activation. We report for the first time the inhibitory activity of juglone ...
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...
Pourali Dogaheh S, Boivin R, Lavoie JP.Severe equine asthma is characterized by airway hyperresponsiveness, neutrophilic inflammation and structural alterations of the lower airways. In asthmatic horses with neutrophilic inflammation, there is insensitivity to corticosteroids characterized by the persistence of neutrophils within the airways with therapy. We hypothesized that hypoxia or oxidative stress in the microenvironment of the lung contributes to this insensitivity of neutrophils to corticosteroids in asthmatic horses. Blood neutrophils isolated from horses with severe asthma (N = 8) and from healthy controls (N = 8)...
Taylor SD, Ivester KM, Stewart C, Page AE, Horohov DW, Couetil LL.Immunological mechanisms involved in the pathogenesis of mild to moderate equine asthma (MEA) are not completely understood. There are limited data on bronchoalveolar lavage fluid (BALF) and blood inflammatory cytokine profiles in racehorses with MEA, and the effect of racing on inflammatory cytokines is unknown. Objective: We hypothesized that inflammatory cytokine gene expression in BALF and resting blood would be higher in racehorses with lower airway inflammation compared to healthy controls, and that gene expression in blood collected immediately post-race would be increased compared to r...
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...
Muko R, Matsuda H, Oikawa MA, Shin T, Matsuda K, Sato H, Sunouchi T, Tanaka A.Histidine-rich glycoprotein (HRG) is an abundant plasma protein that has been identified in most mammals. We first identified whole genome sequence of equine HRG (eHRG) and succeeded to purify eHRG from plasma of horses. Since HRG interacts with various ligands, this protein is thought to be involved in immune response, coagulation, and angiogenesis. Systemic inflammatory response syndrome (SIRS) is characterized as a non-specific, clinical, pro-inflammatory immune response that damage organs and tissues in the host. Recent reports revealed that blood HRG levels in human patients with SIRS are...
Couetil L, Ivester K, Barnum S, Pusterla N.Equine asthma is a common cause of poor performance in racehorses but it is unclear if respiratory viruses contribute to its etiology. The objective of the study was to determine if respiratory viruses were associated with clinical signs and bronchoalveolar lavage fluid (BALF) cytology in Thoroughbred racehorses. Equine herpesviruses (EHV-1, 2, 4, 5) and equine rhinitis A and B viruses (ERBV, ERAV) genomes were quantified by qPCR in nasopharyngeal, tracheal, and BALF samples collected after racing. The relationships between virus detection and load and clinical signs, performance, BALF cytolog...
de la Rebière de Pouyade G, Serteyn D.Despite ongoing research and a widening range of treatment options, laminitis remains a severely damaging condition with poorly understood pathophysiology. Results obtained from cytokine regulation studies during the last decade have highlighted the inflammatory nature of laminitis. This review will describe the role of systemic activation and local infiltration of neutrophils in laminar tissues in the induction of laminitis. Particular emphasis is placed on the role of neutrophil activation in subsequent vascular dysfunction and oxidative and proteolysis imbalances that are pathways previousl...
Muñoz A, Riber C, Trigo P, Castejón F.In order to assess which laboratorial parameters need specific age- and/or gender-related reference values, hematological and biochemical profiles (including hormones) were performed in 205 Spanish foals of 5 groups: A (1-2 months; 20 fillies, 10 colts), B (2-3 months; 24 fillies, 18 colts), C (3-6 months; 25 fillies, 16 colts), D (6-9 months; 20 fillies, 23 colts) and E (9-12 months; 25 fillies, 15 colts). Additionally, 120 adult horses were sampled in order to establish baseline data for this breed in our laboratory. Group E had lower red blood cell number and mean cell volume than B, C and ...
Fortier G, Richard E, Hue E, Fortier C, Pronost S, Pottier D, Lemaitre L, Lekeux P, Borchers K, Thiry E.The aim of this trial was to investigate the putative involvement of equid herpesvirus 2 (EHV-2) in airway inflammation of adult horses. Six horses received corticosteroid treatment, before either mock infection (n=2) or EHV-2 strain LK4 inoculation (n=4). These four horses were also submitted to immunosuppression 84 days post inoculation. EHV-2 was detected by quantitative PCR in respiratory samples up to respectively 21 days and 14 days. Nested PCR, cloning and sequencing allowed the detection of five different 'field' strains throughout the trial. Neutrophils proportions were transiently in...
McKane SA, Canfield PJ, Rose RJ.Sixty-two Thoroughbred horses aged between 1 and 7 years in training in Sydney had bronchoalveolar lavage (BAL) samples collected for cytological examination. All horses, except the yearlings and those with a cough, had raced at the time of the examination and the trainers reported satisfactory performance. Free erythrocytes were found in 73% of samples and haemosiderophages in 90% of the samples, indicating immediate or past occurrences of exercise-induced pulmonary haemorrhage (EIPH). Bronchoalveolar fluid from the yearlings contained significantly less (P < 0.05) erythrocytes and haemosi...
Rettmer H, Hoffman AM, Lanz S, Oertly M, Gerber V.In clinical practice, veterinarians often depend on owner-reported signs to assess the clinical course of horses with recurrent airway obstruction (RAO). Objective: To test whether owner-reported information on frequency of coughing and observation of nasal discharge are associated with clinical, cytological and bronchoprovocation findings in RAO-affected horses in nonstandardised field conditions. Methods: Cross-sectional study comparing healthy and RAO-affected horses. Methods: Twenty-eight healthy and 34 RAO-affected Swiss Warmblood horses were grouped according to owner-reported 'coughing ...
Skarzynski DJ, Szóstek-Mioduchowska AZ, Rebordão MR, Jalali BM, Piotrowska-Tomala KK, Leciejewska N, Łazarczyk M, Ferreira-Dias GM.The innate and adaptive immune mechanisms are key components of regulation of reproductive physiological function and uterine disorders in equine uterus. The predominant immunological response in equine endometrium, characterized by an innate immune response, occurs under estrogens influence, in the follicular phase. Although, the increase in immune-related genes in equine endometrium during estrus has been suggested to play a role in uterine clearance after mating, immune cells and their product, i.e. cytokines play also mandatory role in the luteal development and maintenance, regression of ...
Orard M, Depecker M, Hue E, Pitel PH, Couroucé-Malblanc A, Richard EA.The aim of the study was to determine whether instillation of either 250 mL or 500 mL of saline for bronchoalveolar lavage (BAL) would influence cytological confirmation of inflammatory airway disease (IAD). Thirty client-owned Standardbred racehorses were sampled via endoscopy with 250 mL of saline in one lung and 500 mL in the contralateral lung. The procedure was repeated 72 h later, reversing the volume per lung. The proportions of BAL fluid (BALF) recovered were significantly higher and neutrophil percentages significantly lower with the larger volume. A poor agreement was found between m...
Lambert JL, Fernandez NJ, Roy MF.Band cells and toxic neutrophils are thought to indicate acute and severe systemic illness but no studies have investigated their importance in adult equine emergency admissions. Objective: The objective of this study was to evaluate the association of band cells and toxic neutrophils with systemic inflammatory response syndrome (SIRS) and outcome in horses. Methods: One hundred and five adult horses admitted on emergency basis to a private primary referral practice. Methods: Prospective observational study with sample collection. All horses admitted on emergency basis over the study period we...
Davis KU, Sheats MK.Asthma is a common and debilitating chronic airway disease that affects people and horses of all ages worldwide. While asthma in humans most commonly involves an excessive type 2 immune response and eosinophilic inflammation, neutrophils have also been recognized as key players in the pathophysiology of asthma, including in the severe asthma phenotype where neutrophilic inflammation predominates. Severe equine asthma syndrome (sEAS) features prominent neutrophilic inflammation and has been increasingly used as a naturally occurring animal model for the study of human neutrophilic asthma. This...
Little D, Tomlinson JE, Blikslager AT.Post operative ileus (POI) remains an important cause of post operative morbidity and mortality in the horse. However, clinical progression of naturally occurring cases of POI in both horse and man does not entirely support the 'neurogenic' hypothesis as the sole mechanism of POI; and the hypothesis that inflammation plays a major role at 12-24 h after surgery requires validation. Objective: An inflammatory infiltrate in the muscularis externa and myenteric plexus of equine jejunum is present 18 h following a period of ischaemia. Methods: Samples of normal jejunum, jejunum from the proximal re...
Sanchez-Teran AF, Bracamonte JL, Hendrick S, Burguess HJ, Duke-Novakovski T, Schott M, Hoff B, Rubio-Martínez LM.To evaluate the effect of arthroscopic lavage on systemic serum amyloid A (SAA) and SAA, total protein, nucleated cell count, and percentage of neutrophils in synovial fluid in healthy horses. Methods: Prospective experimental study. Methods: Healthy adult horses (n = 6). Methods: Middle carpal joints were randomly assigned to 1 of 2 treatments: arthrocentesis (controls) or arthroscopic lavage, with 30 day washout period between treatments. Synovial fluid and blood samples were collected at 0, 24, 48, 72, 96, and 120 hours. Measurements included systemic and synovial fluid SAA, as well as ...
Jackson CA, Berney C, Jefcoat AM, Robinson NE.Recurrent airway obstruction (RAO) or heaves is a manifestation of a hypersensitivity to dust, moulds, and spores in the environment of a susceptible horse. Although in the majority of RAO-affected horses, clinical remission can be achieved by keeping horses at pasture to reduce their allergen exposure, this often is not practicable. For this reason, we investigated if changing the environment of a single stall in a 4 stall stable was sufficient to improve lung function and reduce inflammation in RAO-affected horses. In addition, we determined if addition of oral prednisone provided additional...
Berndt A, Derksen FJ, Venta PJ, Ewart S, Yuzbasiyan-Gurkan V, Robinson NE.Recurrent airway obstruction (RAO) is characterized by neutrophilic airway inflammation and obstruction, and stabling of susceptible horses triggers acute disease exacerbations. Stable dust is rich in endotoxin, which is recognized by Toll-like receptor (TLR) 4. In human bronchial epithelium, TLR4 stimulation leads to elevation of interleukin (IL)-8 mRNA expression. The zinc finger protein A20 negatively regulates this pathway. We hypothesized that TLR4 and IL-8 mRNA and neutrophil numbers are elevated and that A20 mRNA is not increased in RAOs during stabling compared with controls and with R...
Mild-moderate (MEA), severe (SEA) equine asthma and exercise-induced pulmonary hemorrhage (EIPH) are common respiratory disorders in horses. The present retrospective study aims to evaluate the role of ultrasonography and endoscopy in the diagnosis of these conditions. Three hundred and three horses were included and divided into SEA, MEA and MEA + EIPH groups, on the basis of history, clinical examination and bronchoalveolar lavage fluid (BALf) cytology; scores were assigned to lung ultrasonography, pharyngeal lymphoid hyperplasia (PLH), tracheal mucus (TM) and tracheal bifurcation edema (TB)...
Anzai T, Timoney JF, Kuwamoto Y, Fujita Y, Wada R, Inoue T.The glossy non-encapsulated strain of Steptococcus equi, NCTC 9682, was compared with the matt strain Hidaka/95/2 which expresses a medium sized capsule and with the mucoid CF32 which expresses a large sized capsule in phagocytosis assays and for virulence in inoculated horses. The three strains, NCTC 9682, Hidaka /95/2 and CF32 produced 2.0, 3.1, and 5.3 mg/g wet cells respectively after 3 h incubation, but similar amounts of M-like proteins, cytotoxin and mitogen. NCTC 9682 showed no resistance to phagocytosis by equine neutrophils regardless of the presence of opsonin while strains Hidaka /...
Bright LA, Dittmar W, Nanduri B, McCarthy FM, Mujahid N, Costa LR, Burgess SC, Swiderski CE. Pasture-associated severe equine asthma is a warm season, environmentally-induced respiratory disease characterized by reversible airway obstruction, persistent and non-specific airway hyper-responsiveness, and chronic neutrophilic airway inflammation. During seasonal exacerbation, signs vary from mild to life-threatening episodes of wheezing, coughing, and chronic debilitating labored breathing. In human asthma, neutrophilic airway inflammation is associated with more severe and steroid-refractory asthma phenotypes, highlighting a need to decipher the mechanistic basis of this disease chara...
Amaral A, Fernandes C, Rebordão MR, Szóstek-Mioduchowska A, Lukasik K, Gawronska-Kozak B, Telo da Gama L, Skarzynski DJ, Ferreira-Dias G.Neutrophil extracellular traps (NETs) fight endometritis, and elastase (ELA), a protease found in NETs, might induce collagen type I (COL1) accumulation in equine endometrium. Metallopeptidases (MMPs) are involved in extracellular matrix balance. The aim was to evaluate the effects of ELA and sivelestat (selective elastase inhibitor) on MMP-2 and MMP-9 expression and gelatinolytic activity, as well as the potential inhibitory effect of sivelestat on ELA-induced COL1 in equine endometrium. Endometrial explants from follicular (FP) and mid-luteal (MLP) phases were treated for 24 or 48 h with ELA...
Stucchi L, Alberti E, Stancari G, Conturba B, Zucca E, Ferrucci F.Mild-moderate equine asthma (MEA) is a common disease of young racehorses characterized by inflammation of the lower airways diagnosed by cytological examination of bronchoalveolar lavage fluid (BALF), and it is considered an important cause of poor performance. The most common parameter of athletic capacity associated with horse performance is the speed at 4 mmol/L of lactate (VLA4). The aim of the present work was to evaluate the relation between the different BALF inflammatory cells and VLA4 in racehorses affected by MEA. A population of Standardbred racehorses that underwent an accurate pr...
Stull CL, Spier SJ, Aldridge BM, Blanchard M, Stott JL.Little information exists on the immunological effects of transport or the use of supplements to minimise transport stress. Objective: To establish baseline ranges and evaluate immunophenotypic and functional changes associated with transport and a nutritional 'adaptogen' supplement. Methods: Horses received either supplement (n = 10) or placebos (n = 9) during the 30 day study. After 28 days in stalls, 12 horses (6 supplement; 6 placebo) were transported for 24 h, then unloaded and recovered. Venous blood samples were collected on Days 1, 14 and 28 to establish baselines, and on Days 28, 29 a...
Loftus JP, Belknap JK, Black SJ.We sought to determine whether a correlation exists between neutrophil infiltration and tissue matrix metalloproteinase-9 (MMP-9) content in digital laminae collected during the prodromal and acute phases of laminitis in horses treated with an aqueous black walnut heartwood extract (BWE). Hoof laminar tissue was obtained at the onset of leukopenia and at the onset of clinical signs of lameness from BWE-treated horses and at equivalent times from control horses. Thin sections of laminae were screened for neutrophils by immunohistochemistry with an anti-CD13 monoclonal antibody and extracts of t...
Ferris RA, Frisbie DD, McCue PM.Current treatments for Persistent mating-induced endometritis such as uterine lavage and oxytocin therapy focus on aiding the uterus in removal of inflammatory products, but these treatments do not modulate the inciting inflammatory response. Biological treatments, such as autologous conditioned serum (ACS) and mesenchymal stem cells (MSCs), have been used in human and veterinary medicine for immunomodulation for over 10 years. The objectives of this project were to evaluate the ability of ACS or MSCs to modulate the inflammatory response to spermatozoa after breeding. Two experiments were pe...
Pirie RS, Dixon PM, McGorum BC.Mould extract inhalation challenges have been used extensively in the investigation of heaves. Such challenges have induced pulmonary neutrophilic inflammation and dysfunction, consistent with, but less severe than the natural disease. However, the method of mould extract production is likely to result in endotoxin contamination. Objective: To investigate whether insufficient dose delivery was responsible for the shortfall in response to inhaled extract compared with natural disease, and whether endotoxin contamination of mould extract contributed to the pulmonary inflammation and dysfunction....
Klier J, Geis S, Steuer J, Geh K, Reese S, Fuchs S, Mueller RS, Winter G, Gehlen H.New therapeutic strategies to modulate the immune response of human and equine allergic asthma are still under extensive investigation. Immunomodulating agents stimulating T-regulatory cells offer new treatment options beyond conventional symptomatic treatment or specific immunotherapy for human and equine allergic airway diseases, with the goal of a homoeostatic T-helper cell balance. The aim of this study was to evaluate the effects of a nebulized gelatin nanoparticle-CpG formulation (CpG-GNP) with and without specific allergens for the treatment of spontaneous allergic equine asthma as a mo...
Bordin AI, Liu M, Nerren JR, Buntain SL, Brake CN, Kogut MH, Cohen ND.Rhodococcus equi is an intracellular bacterium that causes pneumonia in foals and immunocompromised adult horses. Evidence exists that foals become infected with R. equi early in life, a period when innate immune responses are critically important for protection against infection. Neutrophils are innate immune cells that play a key role in defense against this bacterium. Enhancing neutrophil function during early life could thus help to protect foals against R. equi infection. The objective of our study was to determine whether in vitro incubation with the TLR9 agonist CpG 2142 would enhance d...
Lecoq L, Vincent P, Lavoie-Lamoureux A, Lavoie JP.Glucocorticoids have potent anti-inflammatory properties and are frequently used for the treatment of domestic animal species, including horses. They induce a down-regulation of multiple inflammatory pathways through both genomic and non-genomic effects. Currently, little is known on the effects of glucocorticoids on equine peripheral blood neutrophils. Objective: Dexamethasone (DEX), a potent synthetic glucocorticoid, inhibits the functions of equine peripheral blood neutrophils through both genomic and non-genomic effects. Methods: Six healthy adult mixed breed female horses. Methods: To ass...
Holcomb KE, Tucker CB, Stull CL.Housing recommendations for horses invariably include providing access to shade on hot, sunny days, but the potential benefits have not been scientifically studied. This experiment measured physiological, behavioral, and serological responses of horses confined individually to completely shaded (SH) or completely unshaded (SUN) drylot pens during the summer in Davis, CA. Twelve healthy adult horses in a crossover design experienced both treatments for 5 d each. Rectal temperature, respiration rate, skin temperature, and sweat scores were recorded hourly from 1230 to 1730 h daily. Observations ...
Walter J, Neuberg KP, Failing K, Wehrend A.Aim of this study was to compare uterine smears made using the Knudsen catheter, the cytology brush and a uterine culture swab with regard to diagnostic usefulness and the occurrence of neutrophils. Additionally correlation between culture results and the occurrence of neutrophils in uterine smears was investigated. Samples were collected from 340 mares, 81.5% of which were in estrus. Smears made using the cytology brush yielded more endometrial cells per high-power field than those made using the other two instruments (p<0.0001), and a larger proportion had PMNs compared with smears made u...
Naylor JM, Clark EG, Clayton HM.We examined 18 horses with clinical signs of chronic obstructive pulmonary disease (COPD) using physical examination, cytological and bacteriological evaluation of bronchoalveolar fluid, and percutaneous lung biopsy. In 16 cases, histological examination of lung tissue confirmed the diagnosis of COPD. Two horses were excluded: one had uncomplicated bacterial pneumonia and in the other a satisfactory lung biopsy could not be obtained. In horses with COPD, the most common historical complaint was coughing, which was reported in 88%. The most frequently detected abnormal finding on physical exami...
Espinosa G, Plaza A, Schenffeldt A, Alarcón P, Gajardo G, Uberti B, Morán G, Henríquez C.Polymorphonuclear neutrophils (PMN) are the largest leukocyte population in the blood of most mammals including horses, and play an important defensive role in many infectious diseases. However, the mechanisms that increase PMN as one of the main cellular subsets in the defense against pathogens could also be involved in the pathophysiology of dysregulated inflammatory conditions. Mesenchymal stem/stromal cells (MSCs) are a heterogeneous population with a modulatory potential on the inflammatory response and are known to interact with nearly all cells of the immune system, including PMN. In th...
Schwarz BC, van den Hoven R, Schwendenwein I.The myeloperoxidase index (MPXI) was investigated as a diagnostic indicator of systemic inflammation in a retrospective study using data from 859 hospitalised horses. A reference interval of 8.5-10.4 for the MPXI was established. In horses with systemic inflammatory response syndrome (SIRS), the MPXI was significantly lower than in healthy horses, those with localised inflammation and those with sepsis. The MPXI in horses with sepsis was also significantly lower than in healthy animals and those with localised inflammation. Horses in the SIRS group with leucopenia, white blood cell (WBC) count...
