Immunohistochemistry (IHC) is a laboratory technique used to visualize specific antigens in tissue sections of horses through the application of antibodies. This method allows for the detailed examination of the distribution and localization of proteins within equine tissues, providing insights into various physiological and pathological processes. IHC is employed in equine research to study a range of conditions, including infectious diseases, inflammatory responses, and neoplastic disorders. By utilizing specific antibodies that bind to target antigens, researchers can identify cellular and tissue changes, contributing to a better understanding of equine health and disease mechanisms. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and findings of immunohistochemistry in the field of equine research.
Yamate J, Izawa T, Ogata K, Kobayashi O, Okajima R, Kuwamura M, Kotani T, Aoki M.An 11-year-old thoroughbred gelding was euthanatized because of right nasal cavity tumor. The tumor consisted of round to oval cells with a scanty cytoplasm and hyperchromatic nuclei. Homer-Wright rosettes and pseudorosettes, as well as microcysts were seen. Neoplastic cells were immunoreactive to vimentin, S-100 protein, and neuron-specific enolase, glial fibrillary acidic protein and microtube-associated protein in varying degrees, indicating neurogenic nature. Based on these findings, this tumor was diagnosed as an olfactory neuroblastoma. Since this type is an uncommon tumor showing histol...
Weaver RE, Sharif M, Livingston LA, Andrews KL, Fuller CJ.The objective of this study was to assess whether macroscopically normal articular cartilage taken from joints containing focal osteoarthritic lesions is histologically similar to articular cartilage taken from macroscopically normal joints. Metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints were obtained from 10 horses following euthanasia. Gross articular cartilage damage was scored and the cartilage assigned to one of two groups: (1) macroscopically normal cartilage from normal joints (control) and (2) macroscopically normal cartilage from diseased joints in wh...
Herszberg B, Ramos-Barbón D, Tamaoka M, Martin JG, Lavoie JP.Increased airway smooth muscle mass is a prominent feature of asthmatic airway remodeling. Airway smooth muscle hyperplasia occurs in rodent models of experimental asthma, but the relevance of such finding to spontaneously occurring disease in large mammals is unknown. Objective: We examined horses with heaves, a naturally occurring equine asthma related to sensitization and exposure to moldy hay. We hypothesized that airway remodeling occurs in heaves and shares disease mechanisms with asthma. Methods: We quantified the airway smooth muscle mass and the numbers of proliferating and apoptotic ...
Valentine BA, Flint TH, Fischer KA.Serial sections of formalin-fixed, paraffin-embedded muscle biopsy specimens from 28 Quarter Horse, Paint, and draft-related breeds, aged 0.5-23 years, were treated with periodic acid-Schiff (PAS) stain for glycogen and were immunostained to detect ubiquitin expression. On the basis of findings in PAS-stained sections, a diagnosis of equine polysaccharide storage myopathy (EPSSM) was made in 22 horses aged 2-23 years (mean, 9.4 years); samples from 6 horses aged 0.5-15 years (mean, 7.3 years) had a normal PAS staining pattern, with no relevant lesions. Ubiquitin expression was detected in all ...
van Ginneken MM, de Graaf-Roelfsema E, Keizer HA, van Dam KG, Wijnberg ID, van der Kolk JH, van Breda E.To investigate the effects of exercise on activation of mitogen-activated protein kinase (MAPK) signaling proteins in horses. Methods: 6 young trained Standardbred geldings. Methods: Horses performed a 20-minute bout of exercise on a treadmill at 80% of maximal heart rate. Muscle biopsy specimens were obtained from the vastus lateralis and pectoralis descendens muscles before and after exercise. Amount of expression and intracellular location of phosphospecific MAPK pathway intermediates were determined by use of western blotting and immunofluorescence staining. Results: Exercise resulted in a...
Roberto da Costa RP, Ferreira-Dias G, Mateus L, Korzekwa A, Andronowska A, Platek R, Skarzynski DJ.Nitric oxide (NO) plays an important role in angiogenesis and in the regulation of the blood flow. This study was carried out to investigate (i) the effects of endogenous estrogens and progestins and exogenous progesterone (P(4)) (5 ng/ml or 1 microg/ml) or estradiol 17beta (E(2)beta) (50 pg/ml or 1 microg/ml) on in vitro endometrial NO synthesis; (ii) the presence of different isoforms of NO synthase; (iii) and their relationship to microvascular density in the equine endometrium during the estrous cycle. NOS expression was also evaluated in the myometrium. Expression of endothelial and induc...
Kankavi O, Ata A, Gungor O.The presence of surface-active material in the lung alveolus has been known for several decades as being essential for normal lung function. Surfactant is essential for reducing the surface tension at the alveolar air-liquid interface. Pulmonary surfactant is composed of 90% lipids and 10% proteins. There are four non-serum proteins surfactant protein-A (SP-A), surfactant protein-B (SP-B), surfactant protein-C (SP-C) and surfactant protein-D (SP-D) named in chronologic order of discovery. Lung SP-A and SP-D belong to a family of collagen-containing C-type lectin family called collectins. The h...
Kankavi O, Ata A, Akif Ciftcioglu M.The presence of surface-active material in the lung alveolus has been known for several decades as being essential for normal lung function. The host defense and controlling inflammatory processes of the lung are the major functions of SP-A and SP-D. SP-A and SP-D were originally demonstrated in alveolar type II cells, but recent studies have shown extrapulmonary expression of SP-A and SP-D indicating systemic roles of these proteins. Present study describes the presence of SP-A and SP-D in the stallion genital tract, prepuce, prostate, testis, and seminal vesicle using Western blotting and im...
Wilson AD, Harwood L, Torsteinsdottir S, Marti E.Immunoglobulin E forms a minor component of serum antibody in mammals. In tissues IgE is bound by FcvarepsilonRI receptors on the surface of mast cells and mediates their release of inflammatory substances in response to antigen. IgE and mast cells have a central role in immunity to parasites and the pathogenesis of allergic diseases in horses and other mammals. This paper describes the production of several novel monoclonal antibodies that detect native equine IgE in immunohistology, ELISA and Western blotting. An antigen capture ELISA to quantify equine IgE in serum has been developed using ...
Rütten M, Lehner A, Pospischil A, Sydler T.Listeria monocytogenes infection, although rare in horses, can lead to septicaemia, gastroenteritis and abortion or stillborn foals. Equine cerebral listeriosis has been reported, but only in newborn animals. This report describes a Freiberger gelding with severe neuronal symptoms of sudden onset. The animal collapsed within 24 h and was humanely killed. Necropsy revealed multiple small brown to reddish foci within the brain stem and pons. Histopathology demonstrated multifocal suppurative meningoencephalitis with microabscesses and occasional intra-lesional, coccoid to rod-shaped, bacteria. T...
Scott P, Witonsky S, Robertson J, Daft B.Equine protozoal myeloencephalitis (EPM), caused by Sarcocystis neurona infection in the central nervous system (CNS), affects up to 1% of all horses during their lifetimes. Neither the protective immune response nor the immunopathology associated with the disease is well understood. To begin to clarify the pathogenesis of the disease, immunohistochemical staining for B and T lymphocytes was performed on spinal cord sections obtained from 17 horses, all of which were all positive for S. neurona based on immunohistochemical staining. Fifteen of the 17 horses included in the study were killed du...
Szeredi L, Molnár T, Glávits R, Takai S, Makrai L, Dénes B, Del Piero F.Rhodococcus equi was isolated from lung, liver, spleen, and stomach content of two aborted equine fetuses of 7 and 8 months gestation from two different farms. Lesions included diffuse pyogranulomatous pneumonia with numerous Gram-positive coccobacilli within the cytoplasm of macrophages, multinucleated Langhans giant cells and neutrophils, and enhanced extramedullary hematopoiesis with megakaryocytosis within the liver and spleen. Detection of R. equi was made by bacteriology and immunohistochemistry for R. equi and VapA, the virulence factor of R. equi. R. equi and VapA were identified withi...
Parlevliet JM, Pearl CA, Hess MF, Famula TR, Roser JF.The presence of steroids and their receptors throughout development, specifically androgen receptor (AR), estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta), in the epididymis of a high estrogen producing species like the stallion has not been determined. Epididymal and testicular samples were collected for analysis of testosterone and estradiol-17beta (E(2)) concentrations and for immunolocalization of AR, ERalpha and ERbeta. The concentration of testosterone in the testis and epididymis were not different among age groups (P>0.05). AR was localized in the principal cell...
Soffler C, Hermanson JW.We studied the forelimb interosseus muscle in horses, Equus caballus, to determine the muscular properties inherent in its function. Some authors have speculated that the equine interosseus contains muscle fibers at birth only to undergo loss of these fibers through postnatal ontogeny. We describe the muscle fibers in eight interosseus specimens from adult horses. These fibers were studied histochemically using myosin ATPase studies and immunocytochemically using several antibodies directed against type I and type II myosin heavy chain antibodies. We determined that 95% of the fibers were type...
Bolam CJ, Hurtig MB, Cruz A, McEwen BJ.To study osteoarthritis in the equine medial femorotibial (MFT) joint after a single traumatic injury. Methods: 10 mature horses. Methods: In vitro explant cultures were used to determine injury threshold for stifle joint cartilage. Contusive impacts were applied to the medial femoral condyle (MFC), and horses were followed for 84 (n = 5) and 180 days (5). Synovial fluid samples were collected every 14 days for determination of sulphated glycosaminoglycan (sGAG) concentrations. Radiographic and lameness evaluations were performed. Gross and histologic descriptions, and immunohistochemistry, ca...
Staszyk C, Duesterdieck KF, Gasse H, Bienert A.Immunohistochemical detection of lymphatic capillaries was performed in the periodontium of maxillary and mandibular cheek teeth from 6 horses (aged 3-23 years). Tissue sections of the periodontium were taken at 4 different horizontal levels along the long axis of the tooth. The specimens were processed for immunoreaction with anti-Prox1, in order to distinguish lymphatic endothelium from blood vascular endothelium. Lymphatic vessels were detected in all periodontal tissues except for the dental cementum. Lymphatic capillaries were most densely distributed in the gingiva compared to other tiss...
Hejmej A, Wiszniewska B, Kosiniak-Kamysz K, Sadowska J, Bilińska B.Distribution of androgen receptors (ARs) in the epididymal duct and prostate of three entire stallions and one bilaterally cryptorchid horse was studied immunohistochemically using a polyclonal rabbit antiserum against the ARs. In both the healthy stallions and the cryptorchid, the epithelial cells of the epididymides showed nuclear staining for ARs. The intensity of AR-staining in the principal cells of the epididymis was stronger than that of the basal cells. In the prostate, the glandular secretory cells were moderately stained whereas the basal cells expressed weak AR-staining. Immunostain...
Polikepahad S, Paulsen DB, Moore RM, Costa LR, Venugopal CS.To immunohistochemically determine the expression of endothelin (ET) receptors in bronchial smooth muscle and epithelium of healthy horses and horses affected by summer pasture-associated obstructive pulmonary disease (SPAOPD). Methods: Tissue specimens obtained from 8 healthy and 8 SPAOPD-affected horses. Methods: Horses were examined and assigned to healthy and SPAOPD groups. Horses were then euthanatized, and tissue specimens containing bronchi of approximately 4 to 8 mm in diameter were immediately collected from all lung lobes, fixed in zinc-formalin solution for 12 hours, and embedded in...
Kumar P, Timoney JF.The tonsil of the soft palate was an oval, flat structure located centro-rostrally on the oral surface of the soft palate. Its stratified squamous non-keratinized epithelium was perforated by holes or small crypts the deeper parts of which were loosely spongiform inter-digitated with lymphoid tissue. These unusual features have not previously been reported in tonsils of any species. Crypts and reticulated epithelium as found in the lingual and palatine tonsils were not observed. Lectins showed varying affinities for specific layers of the epithelium. M cells were not observed. A few Langerhans...
Fink C, Tatar M, Failing K, Hospes R, Kressin M, Klisch K.Serotonin (5-hydroxytryptamine, 5-HT), a regulatory amine of mucosal enterochromaffin cells plays an important role in the control of gastrointestinal smooth muscle contraction and epithelial secretion. Serotonin has also been associated with gastric ulcers, diarrhoea and abdominal pain. In spite of the high incidence of these gastrointestinal disorders in newborn foals and adult horses, no data are available regarding 5-HT immunoreactive cells (i.c.) in the gastrointestinal tract (GIT) of foals, and for adult horses, data are incomplete and contradictory. In this study, the distribution and r...
Bovell DL, Lindsay SL, Corbett AD, Steel C.Western blot analysis showed that sweat gland cells from freely sweating horses expressed the water channel aquaporin-5 (AQP-5). Immunohistochemistry revealed a strong AQP-5-like activity reaction at the apical membrane of the glandular secretory cells, which was absent from the surrounding myoepithelium and all other skin structures. In anhidrotic horses, AQP-5 was also found at the apical membrane of the luminal sweat gland cells, but the level of expression reduced with the length of time that the animal had displayed anhidrosis. The level of AQP-5 expression was substantially reduced in an...
Spiegel IB, White SD, Foley JE, Drazenovich NL, Ihrke PJ, Affolter VK.Nine horses from ages 5 to 21 years were diagnosed with cutaneous equine sarcoidosis (ES) over an 18-year period. In addition to skin, the lungs were frequently involved, with other organ systems affected less commonly. A predisposition for thoroughbreds and geldings was noted. Cutaneous lesions and signs included crusts, scales, alopecia and pruritus. These were found at various sites, particularly the legs/thighs/elbows, thorax, neck, face and ventral abdomen. Three horses were euthanized shortly after hospitalization; others survived as long as 12 years. Histopathologic stains, immunohistoc...
Yasui T, Tsukise A, Fukui K, Kuwahara Y, Meyer W.The distribution of complex glycoconjugates and antimicrobial substances in the ceruminous glands of the horse (Equus przewalskii f. dom., type: pony) was studied using carbohydrate histochemical and immunohistochemical methods. The epithelial cells and luminal secretion of these glands exhibited considerable amounts of glycoconjugates with various saccharide residues, such as alpha-D-mannose, alpha-L-fucose, beta-D-galactose, beta-N-acetyl-D-glucosamine and sialic acid, including O-acetylated sialic acid. Several sugars (alpha-D-mannose, alpha-L-fucose, and beta-D-galactose) were also detecta...
Geburek F, Ohnesorge B, Deegen E, Doeleke R, Hewicker-Trautwein M.We report the historical, clinical and histopathological characteristics of skin lesions in biopsies from 37 heavy draught horses with chronic pastern dermatitis. The skin lesions were divided into four macroscopic groups: scaling (group I, n=5), hyperkeratotic and hyperplastic plaque-like lesions (group II, n=14), nodular skin masses (group III, n=16) and verrucous skin lesions (group IV, n=2). The principal histological findings were hyperkeratosis and epidermal hyperplasia. There was a gradual increase in epidermal hyperplasia from groups I to IV, suggesting that the lesions represent diffe...
Bertone AL, Bramlage LR, McIlwraith CW, Malemud CJ.To compare articular cartilage from horses with naturally developing osteochondrosis (OC) with normal articular cartilage and healing cartilage obtained from horses with experimentally induced osteochondral fractures. Methods: 109 specimens of articular cartilage from 78 horses. Methods: Morphologic characteristics, proteoglycan (PG), and type II collagen were analyzed in articular cartilage of OC specimens (group 1), matched healing cartilage obtained 40 days after experimentally induced osteochondral fractures (group 2), and matched normal cartilage from the same sites (group 3). Results: 79...
Hosaka Y, Kirisawa R, Ueda H, Yamaguchi M, Takehana K.Tumor necrosis factor (TNF) receptors (TNF-R)-mediated cell survival or apoptosis has been demonstrated in many cells, but little is known about survival or apoptotic signals via TNF-R1 in tendinocytes. In this study, we focused on four signaling factors, TNFalpha, TNF-R1, TNFR-associated factor2 (TRAF2) and caspase-3, in order to elucidate the signaling events in tendinocytes. Samples were obtained from normal, inflamed and scar-formed equine superficial digital flexor tendons. To detect these signaling factors, samples were subjected to immunohistochemistry and Western blot analysis, and som...
Epstein V, Hodge D.Multiple cutaneous lymphosarcomas were diagnosed in an 8-year-old Thoroughbred stallion presented for evaluation of lumps on its scrotum. Histological examination of skin biopsy samples showed a homogenous pattern of lymphoid tissue suggestive of a T-cell lymphosarcoma. Immuno-histochemical tests showed a positive reaction to Rabbit/Anti-Human T-Cell, CD3 antibodies confirming T-cell lymphosarcoma. The animal was not treated and was subsequently euthanased.
Boerboom D, Paquet M, Hsieh M, Liu J, Jamin SP, Behringer RR, Sirois J, Taketo MM, Richards JS.Misregulation of the Wnt/beta-catenin signaling pathway is a hallmark of several forms of cancer. Components of the Wnt/beta-catenin pathway are expressed in ovarian granulosa cells; nevertheless, its potential involvement in granulosa cell tumorigenesis has not been examined. To this end, human (n = 6) and equine (n = 18) granulosa cell tumors (GCT) were analyzed for beta-catenin expression by immunohistochemistry. Unlike granulosa cells of normal ovaries, most (15 of 24) GCT samples showed nuclear localization of beta-catenin, suggesting that activation of the Wnt/beta-catenin pathway plays ...
Fink C, Hembes T, Brehm R, Weigel R, Heeb C, Pfarrer C, Bergmann M, Kressin M.In the glandular stomach, gap junctional intercellular communication (GJIC) plays an important role in the gastric mucosal defense system, and loss of GJIC is associated with ulcer formation. In spite of the high incidence of gastric ulcers in horses, particularly at pars nonglandularis, the presence of gap junctions in the equine stomach has not yet been studied. The objective was to obtain basic data on the distribution of gap junction protein connexin 32 (Cx32) in the different regions of normal equine gastric mucosa. Samples of mucosa were taken from seven horses at cardiac, fundic, and py...
Arai KY, Tanaka Y, Taniyama H, Tsunoda N, Nambo Y, Nagamine N, Watanabe G, Taya K.In this study, the expression patterns of inhibins, activins, insulin-like growth factor-I (IGF-I) and steroidogenic enzymes in equine placentae recovered during the latter two-thirds of gestation were examined. Concentrations of inhibin A and inhibin pro-alphaC in endometrial and fetal placental tissue homogenates were very low during the period examined, whereas these tissues contained high concentrations of activin A. In both maternal endometrial and fetal placental tissues, activin A levels decreased as pregnancy progressed. Expression of inhibin alpha-subunit was not observed in the place...
Wilsher S, Gower S, Allen WR.Previous reports documenting progesterone receptors (PR) and oestrogen receptors (ER) in the endometrium of early pregnant mares included specimens only up to Day 20 post ovulation. This study aimed to localise PR and ERα on equine feto-maternal tissues between Days 20 and 68 to encompass the period around fixation of the conceptus, development of the endometrial cups and attachment and initial interdigitation of the allantochorion. During early pregnancy mares had the same pattern of PR in the endometrium as that reported for other mammals; namely, a loss of PR from the endometrial epithelia...
Pollitt CC, Daradka M.Surgical stripping of the hoof wall results in a wound that heals remarkabley well. In contrast, lamellae recovering from laminitis are often deformed. Investigating lamellar wound healing may aid understanding of laminitis. Objective: To document temporal changes in the lamellar basement membrane (BM), dermis and epidermis after surgery. Methods: Wall strips were made in the dorsal hoof wall midline of 6 mature horses. Immunohistochemistry was used to document changes in the basement membrane (BM) and detect proliferation of epidermal cells in lamellar tissues harvested at intervals. A confor...
Jones CJ, Wooding FB, Dantzer V, Leiser R, Stoddart RW.The glycosylation of the equine interhaemal barrier and areola was studied throughout the period of gestation. Placentae of 35, 37, 50, 119, 152, 200, 280 and 300 days gestation were investigated, using semithin plastic embedded sections and a panel of 15 biotinylated lectins with an avidin-peroxidase revealing system. Glycosylation of the trophoblast and maternal epithelium showed the most change during the first 50 days of gestation, being associated with the initial stages of adhesion and attachment. In the trophoblast, non-bisected tri/tetraantennary complex N-glycan was only evident after...
Lydka M, Kotula-Balak M, Kopera-Sobota I, Tischner M, Bilińska B.Specific patterns of cytoskeletal filaments reflect a functional state of the cell. In testicular cells intermediate filaments (IFs) are of the vimentin type. Since it is known that Sertoli cells regulate the spermatogenic function in the male gonad, it became important to propose a system that could quantify the state of seminiferous tubular quality. To date, a Johnsen score system has never been used to equine testes. Objective: To demonstrate the expression pattern of vimentin in testes of mature Arabian stallions and correlate its distribution with grade of seminiferous tubule impairment a...
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...
Cotovio M, Monreal L, Navarro M, Segura D, Prada J, Alves A.Histochemical and immunohistochemical techniques have been used to detect fibrin deposits in different tissues in humans and experimental animal models with disseminated intravascular coagulation (DIC). Fibrin deposits also have been observed in horses with severe ischemic and inflammatory disorders by histochemical stainings (phosphotungstic acid hematoxylin [PTAH]). Objective: Immunohistochemical (IHC) methods can be used to accurately detect fibrin deposits in horses at risk of DIC. Methods: Tissue-organ samples collected on postmortem examination from 87 horses with severe inflammatory and...
Teubner A, Müller K, Bartmann CP, Sieme H, Klug E, Zingrebe B, Schoon HA.The aim of this study was to determine the effect of the anabolic steroid testosterone on the testicular vascularization, angiogenesis and expression of angiogenic factors, and their receptors in testes of peripubertal stallions. Seven peripubertal stallions were treated with Durateston and castrated either 4 (treatment group 1 [TG1]) or 12 weeks (TG2) after the last injection. The castration of seven untreated control stallions (control group [CG]) took place within the same time. In the testicular specimens, volume density (VD), numerical density (ND), and area of vessels were determined mor...
Desantis S, Ventriglia G, Zizza S, Guaricci AC, Losurdo M, Zarrilli A, Albrizio M.The presence of the mu-opioid receptor (MOR) was investigated in the mare oviduct during oestrus and anoestrus, by means of immunoblotting and immunohistochemistry. Immunoblotting analysis showed that the MOR protein is expressed as 65, 50 and 30 kDa forms in the infundibulum and ampulla both in oestrus and anoestrus, while the 30 kDa form is absent in the isthmus. Moreover, different levels of expression were observed along the ampulla in the two periods examined. Immunohistochemistry revealed MOR in the mucosal epithelium, stromal cells, myocytes and blood vessels. Ciliated cells expressed M...
Ryan PL, Klonisch T, Yamashiro S, Renaud RL, Wasnidge C, Porter DG.Immunoreactive, chromatographic and molecular techniques were used to study the expression of relaxin in mare ovaries at different stages of the oestrous cycle. Relaxin in follicular fluid ranged from 1.6 to 2.5, from 1.4 to 5.2, from 1.2 to 6.7 and from 1.0 to 3.5 ng ml-1 in small ( 2 3 4 cm) follicles, respectively, and total content of fluid relaxin per follicle increased (P < 0.05) with follicular size. When subjected to reverse phase HPLC analysis, follicular fluid yielded absorbance profiles corresponding closely to those of purified relaxin, and immunoreactive peaks in follicular f...
Sonea IM, Bowker RM, Robinson NE, Broadstone RV.Immunohistochemical methods were used to determine the distribution of pulmonary nerves containing either an enzymatic marker of adrenergic nerves, dopamine beta hydroxylase, or the putative neurotransmitter neuropeptide Y in 7 equids with healthy lungs. Nerves immunoreactive for these substances were found on airway smooth muscle in nearly all the samples of healthy equine lung examined. These nerves were generally more numerous in the larger airways but could be detected even in noncartilaginous bronchioles. Pulmonary and bronchial vessels also contained numerous immunoreactive nerves. On th...
Meyerholz DK, Caston SS, Haynes JS.An Appaloosa filly was born with a ventral midline, approximately 8 x 12 x 15 cm subcutaneous cervical mass. The nonencapsulated mass was composed of interlacing and haphazard bundles of spindle cells on moderate to abundant loose myxomatous stroma. A moderate number of cells showed cross striations with minor nuclear variation and a low mitotic rate. Immunohistochemical staining for myoglobin, desmin, actin, vimentin, and S-100 was positive and negative for glial fibrillar antigen and keratin. Rhabdomyomas are rare benign tumors of striated muscle. Rhabdomyomas described previously in the vet...
Burns TA, Watts MR, Weber PS, McCutcheon LJ, Geor RJ, Belknap JK.In EMS-associated laminitis, laminar failure may occur in response to energy failure related to insulin resistance (IR) or to the effect of hyperinsulinemia on laminar tissue. 5'-Adenosine-monophosphate-activated protein kinase (AMPK) is a marker of tissue energy deprivation, which may occur in IR. Objective: To characterize tissue AMPK regulation in ponies subjected to a dietary carbohydrate (CHO) challenge. Methods: Twenty-two mixed-breed ponies. Methods: Immunohistochemistry and immunoblotting for total AMPK and phospho(P)-AMPK and RT-qPCR for AMPK-responsive genes were performed on laminar...
Rendle DI, Durham AE, Thompson JC, Archer J, Mitchell M, Saunders K, Millere J, Paillot R, Smith KC, Kydd JH.Lymphoid leukaemia (LL) is rare in equids. In man, immunophenotypic classification identifies distinct leukaemic types with different treatment strategies. Improved understanding and classification of equine LL may allow similar advances. Objective: To document the clinical, immunophenotypic and functional characteristics in 6 cases of equine LL of T-cell origin. Methods: The clinical records and pathological findings from 6 cases of equine LL were analysed. Immunohistochemistry to identify T or B lymphocytes was performed on paraffin embedded tissues in 4 cases. Peripheral blood mononuclear c...
Taya K, Nagata S, Tsunoda N, Nagamine N, Tanaka Y, Nagaoka K, Taniyama H, Nambo Y, Watanabe G.In this study, clear seasonal changes in the circulating concentrations of immunoreactive inhibin were observed in stallions throughout the year. The highest plasma concentrations of immunoreactive inhibin were observed during the breeding season and the lowest concentrations were observed during the nonbreeding season. There was positive correlation between the circulating concentrations of immunoreactive inhibin, steroid hormones and gonadotrophins. Inhibin alpha subunit positive staining was observed in Sertoli cells and more clearly in Leydig cells. Both cell types also stained positively ...
Puff C, Herder V, Philipp A, Baumgärtner W.A 15-year-old Haflinger gelding presented with a mass in the left nictitating membrane. Two biopsies and the excised nictitating membrane were taken at different time points as a result of reoccurrence of the mass and submitted for histopathologic evaluation. The horse was euthanized as a result of poor prognosis following the reoccurrence of the mass after surgical removal. Histologically, the mass consisted of dilated, thin-walled vascular clefts and channels, lined by flattened to cuboidal endothelial cells with moderate cellular pleomorphism. There was up to 1 mitotic figure per high power...
Méndez A, Martín de las Mulas J, Bautista MJ, Chacón F, Millán Y, Fondevila D, Pumarola M.The presence and distribution of S100 protein (alpha and beta subunits), cytokeratin polypeptides, glial fibrillary acidic protein, neurofilaments, vimentin, neuron specific enolase, synaptophysin, HLA class II DR antigen, and pituitary hormones (prolactin, adrenocorticotropic hormone and human chorionic gonadotrophin) in stellate cells were studied immunohistochemically in four normal canine pituitary glands, five canine pituitary adenomas, two canine pituitary carcinomas and two equine pituitary adenomas (with surrounding normal glandular tissue). Stellate cells of the pars distalis and pars...
El-Gameel SM, Al-Mokaddem AK, Salaeh NMK, Attia MM.Equine gastrointestinal tract is infected with () which is highly pathogenic parasite for its harmful effect on cranial mesenteric artery during its migration. So, this study was applied for identification of in donkeys ultramorphologically and molecularly. In addition to, detection of the pathological effect of larval stage of on the mesenteric arterial system using histopathology and immunohistochemistry. During the period from September to December; 2019, 60 male and 20 female donkeys at the Giza Zoo was postmortem examined. adults and larvae were collected from the large intestine and ...
Gauff FC, Patan-Zugaj B, Licka TF.To determine the effect of short-term hyperinsulinemia on the localization and expression of endothelin receptor (ETR)-A and ETR-B in lamellar tissue of the forelimbs of horses. Methods: Distal portion of 15 cadaveric forelimbs from healthy adult horses (1 limb/horse) obtained immediately after slaughter at an abattoir. Methods: Each forelimb was assigned to 1 of 3 treatment groups (perfused with autologous blood for 10 hours [control perfusion; n = 5], perfused with an insulin [142 ± 81 μU/mL] perfusate for 10 hours [insulinemic perfusion; 5], or not perfused [unperfused control; 5]). Immun...
IJzer J, van den Ingh TS.A 15-year-old Dutch Warmblood mare presented with respiratory distress and anorexia. Clinical examination revealed liquothorax and an abdominal mass. At necropsy, an infiltrating tumour was found in the visceral trunk, continuing through the diaphragm into the mediastinum. Histopathology, immunohistochemistry and electronmicroscopy showed empty channels lined by atypical endothelial cells, and neoplastic cells in a disorganized pattern, consistent with the diagnosis of a lymphangiosarcoma.
Knowles S, Blas-Machado U, Butler AM, Gomez-Ibañez SE, Lowder MQ, Fayrer-Hosken RA.An 11-year-old Oldenburg mare presented with a 3-month history of weight loss and swelling of the posterior right mandible. Physical examination and radiographs showed a soft-tissue mass in the right mandible with foci of mineralization, periosteal proliferation, and a retained molar. The tumor increased in size over several weeks, and the mare was euthanized. On necropsy, a 24 cm × 15 cm × 15 cm firm, white mass had obliterated the posterior right mandible. The mass was multinodular with discrete clusters of blood-filled cystic spaces. Histologically, the mass was composed of neoplastic ...
Sutton GA, Viel L, Carman PS, Boag BL.Equine herpesvirus-1 (EHV-1) causes respiratory disease, neonatal death, abortion and neurologic disease. The main purpose of this study was to identify viral antigen in respiratory tract samples by immunoperoxidase staining. Six pony foals were selected on the basis of demonstrating seronegativity to EHV-1 by virus neutralization and housed in isolation. They were infected experimentally by administering EHV-1 nebulized ultrasonically through a face mask. Successful infection was clinically apparent as each of the foals had febrile responses, nasal discharge, and enlarged submandibular lymph ...
Watson ED, Buckingham J, Björkstén T, Nikolakopoulos E.The presence of oxytocin in the mare uterus was determined by radioimmunoassay of tissue extracts and uterine lavage fluid, and by immunohistochemistry. Samples were obtained from mares during the oestrous cycle and on day 14 of pregnancy. Immunoreactive oxytocin was detected in extracts of endometrium and myometrium, and in uterine lavage fluid. In tissue sections, the luminal epithelium, the epithelium of the superficial, but not deep, glands, blood vessel walls and myometrium all stained positively for oxytocin, whereas only the luminal epithelium and epithelium of the superficial glands st...
Bogaert L, Heerden MV, Cock HE, Martens A, Chiers K.Ten equine skin tumors that had been classified as schwannomas on routine histological examination were analyzed by polymerase chain reaction for bovine papillomavirus DNA. All 10 were positive for bovine papillomavirus 1 or 2, and all 10 were immunohistochemically negative for S-100 protein and strongly positive for vimentin. Nine tumors were moderately positive for laminin and 8, for smooth muscle actin. Five tumors were variably and weakly positive for type IV collagen. The lack of S-100 protein expression made Schwann cells an unlikely cell of origin, as opposed to peripheral nerve sheath ...
Wohlsein P, Pohlenz JF, Davidson FL, Salt JS, Hamblin C.The distribution of viral antigen was studied in various tissues of three ponies, aged 3-4 years, infected experimentally with a virulent strain of African horse sickness virus (AHSV) serotype 4. Tissues were collected from the animals in the terminal stage of the peracute form of the disease and from one noninfected horse, included as a control. A polyclonal antibody with specificity for AHSV, plus the nonstructural protein NS2, was used in a sensitive avidin-biotin-peroxidase-complex (ABC) method performed on formalin-fixed, paraffin-embedded tissue sections. AHSV antigen was located primari...
Miesner T, Wilkie D, Gemensky-Metzler A, Weisbrode S, Colitz C.At The Ohio State University from 1994-2006 six of seven horses evaluated for primary orbital disease were diagnosed with extra-adrenal paraganglioma (EAPG). The horses ranged in age from 14 to 24 years, with a mean of 16.8 years. Duration of clinical signs was 1.5 years to 5 years, with a mean of 2.8 years. Clinical signs varied, but all six had non-painful exophthalmus of the right eye. Five horses had complete ocular exams reported; three of five had decreased to absent vision, two of five had pale optic nerves, and in three of five, difficulty of retropulsion of the globe was noted. Diagno...
Ramery E, Fievez L, Fraipont A, Bureau F, Lekeux P.The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses' airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immunohistochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cell...
Watson ED, Thomson SR.Aromatase P-450 (P-450arom) is a crucial regulatory enzyme that is necessary for conversion of androgens to oestrogens. Corpora lutea and follicles were obtained from the ovaries of cyclic mares and from mares at day 20 and days 40-70 of pregnancy. The presence of P-450arom within specific cell types was investigated by immunostaining to determine potential sites of oestrogen synthesis. Immunoreactivity for P-450arom was confined to the granulosa layer of non-atretic follicles > 5 mm in diameter and to corpora lutea at all stages of the oestrous cycle and during pregnancy. These findings co...
Williams JM, Lin YJ, Loftus JP, Faleiros RR, Peroni JF, Hubbell JA, Ravis WR, Belknap JK.Laminitis is a serious complication of horses suffering from sepsis/endotoxaemia-related events. Laminitis in horses and organ injury in human sepsis are both reported to involve inflammatory injury to the laminae/organs including early activation of endothelium and leucocytes leading to emigration of neutrophils into the tissue interstitium. In the black walnut extract (BWE) model, systemic inflammatory events coincide with marked increase in laminar mRNA concentrations of inflammatory genes including proinflammatory cytokines (i.e. IL-1beta, IL-6), COX-2, chemokines (i.e. IL-8) and endotheli...
Klomkleaw W, Kasashima Y, Fuller GA, Kobayashi A, Yoshihara T, Oikawa MA, Izumisawa Y, Yamaguchi M.An anatomical study of horse lumbrical muscle (Lm) was carried out by light and electron microscopy in combination with immunochemical and cytochemical methods. Paraffin sections were subjected to haematoxylin and eosin (H & E) and Masson's trichrome staining for morphometric analysis. Paraffin sections were also used for immunostaining by anti-PGP 9.5 for reaction with nerve-protein associated-structures, anti-heat-shock protein 70 (hsp 70) for detection of gene expression changes, anti-fast myosin for the determination of muscle fibre types, and for detection of apoptotic gene expression...
Hopster-Iversen C, Hopster K, Staszyk C, Rohn K, Freeman D, Rötting AK.Large intestinal diseases in horses are characterised by inflammation, which could arise from the disease process with some contribution from intestinal manipulation. The effects of the latter are unknown but important to surgeons and could contribute to post operative complications. Objective: To characterise type and degree of intestinal inflammation induced by various mechanical stimuli in the equine ascending colon. Methods: Laparotomy was performed in 12 horses, the left dorsal colon exteriorised and 3 segments randomly exposed to different mechanical manipulations: 1) enterotomy, 2) ente...
