The study of cells in horses encompasses the examination of various cell types and their functions within the equine body. Cells are the basic structural and functional units of life, and in horses, they contribute to numerous physiological processes, including growth, repair, and immune responses. Different cell types, such as red blood cells, white blood cells, and muscle cells, each perform specific roles that are vital for maintaining the health and homeostasis of the horse. This topic includes research on cellular mechanisms, cellular responses to disease or injury, and the application of cellular biology in equine medicine. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and significance of cells in equine biology and health.
Okumura M, Fujinaga T.The role of keratan sulphate (KS) as a metabolic marker of cartilage was evaluated using an in vitro model of equine articular cartilage. Articular cartilage was harvested from clinically healthy 6-month-old foals (n = 3). Chondrocytes were centrifuged and cultured as pellets. Chondrocyte pellets were stimulated by insulin-like growth factor-I alpha (IGF-I alpha) or interleukin-1 alpha (IL-1 alpha) for 2 weeks. The concentrations of sulphated glycosaminoglycans (GAG) and KS in the culture media were measured by a 1,9-dimethyl-methylene blue (DMMB) colorimetric assay and an inhibition enzyme-li...
Baskurt OK, Meiselman HJ.To evaluate the rheologic responses of equine versus human RBC to oxidant stress induced by superoxide anions. Methods: Equine blood samples were obtained from 8 healthy, 3- to 6-year-old various breed horses of either sex; human blood samples were obtained from 8 healthy adults. Methods: Washed RBC were exposed to superoxide anions generated by the xanthine oxidase (XO)-hypoxanthine system (XO activity of 0 to 0.1 U/ml). Deformability of RBC was assessed by ektacytometry, and RBC aggregation was measured in autologous plasma or 3% solution of dextran 70 via a defined-shear photometric techniq...
Kingsmill VJ, Gray C, Boyde A.To address possible differences in the resorbability of cranial and postcranial bone, slices of equine frontal bone and leg (first phalanx or third metacarpus) were seeded with embryonic chick bone cells and cultured for 20-24h. After removing the cells and drying the specimens, the areas and volumes of more than 800 resorption pits in each set were measured using a video-rate reflection confocal microscope system. Relative mineralization densities were determined by quantitative electron backscattering analysis. The mean mineralization density was greater in the leg bone, but the mean depths ...
Walters KW, Corbin CJ, Anderson GB, Roser JF, Conley AJ.Estrogen production by the preimplantation equine embryo is presumed to be important in maternal-conceptus communication in the mare. The synthesis of C(18) estrogens from C(19) androgens requires cytochrome P450 aromatase (P450(arom)) in the conceptus, but little information is available on the specific tissue location or potential developmental patterns of expression for the horse. The goal of this research was to localize P450(arom) in the equine conceptus by immunocytochemistry and in situ hybridization. Intact blastocyst-stage embryos were collected by nonsurgical flush on Days 12-15 of p...
Rakestraw PC, Snyder JR, Sanders KM, Shuttleworth WC.To evaluate electrical activity of jejunal circular muscle in horses and characterize electrical responses to stimulation by intrinsic inhibitory neurons. Methods: Portions of jejunum obtained from horses euthanatized for reasons other than gastrointestinal tract disease. Methods: Isolated circular muscle preparations were perfused with oxygenated modified Krebs solution. Glass microelectrodes were used for intracellular recording of membrane potentials from single smooth muscle cells. Electrical activity and responses to electrical field stimulation (EFS) of intrinsic neurons in the presence ...
Okumura M, Tagami M, Fujinaga T.The role of keratan sulphate (KS) as a marker of cartilage metabolism was evaluated by using an in vitro model of equine articular cartilage. Articular cartilage was harvested from clinically healthy 6-month-old foals (n=3). Chondrocytes were centrifuged and cultured as pellets. Chondrocyte pellets were stimulated by insulin-like growth factor (IGF)-Ialpha or interleukin (IL)-1alpha for 2 weeks. The sulfated glycosaminoglycans (GAG) and antigenic KS concentrations in the culture media were measured by a 1,9-dimethyl-methylene blue (DMMB) colorimetric assay and an inhibition ELISA using a 1/14/...
Bureau F, Bonizzi G, Kirschvink N, Delhalle S, Desmecht D, Merville MP, Bours V, Lekeux P.Asthma is a chronic inflammatory disease of the airways, in which many inflammatory genes are overexpressed. Transcription factor, nuclear factor-kappaB (NF-kappaB), which is thought to control the transcriptional initiation of inflammatory genes, has been poorly investigated in asthma. In the present report, bronchial cells (BCs), recovered by bronchial brushing in healthy and heaves-affected horses (i.e., an animal model of asthma), were assessed for NF-kappaB activity. Small amounts of active NF-kappaB were present in BCs of healthy horses, whereas high levels of NF-kappaB activity was foun...
Gray AW, Davies ME, Jeffcott LB.We report on novel methods to isolate osteoclasts (OC s) and generate osteoclast-like cells (OCL s) from the bone and bone marrow of the equine femur. OC s were successfully isolated from bone scrapings taken from the endosteal surface of the femurs of three horses. OCL s were generated from bone marrow cells taken from the same animals. The validity of using the formation of OCL s as a method for studying OC differentiation and activity was confirmed by the similar characteristics of these two cells. In particular, they both were multinuclear, expressed the enzyme tartrate resistant acid phos...
Rush BR, Flaminio MJ.Nonspecific immunomodulators are substances that induce non-antigen-specific enhancement of the body's native or acquired defense mechanisms. Immunomodulant preparations are most often used for treatment of chronic, viral, or bacterial infection with evidence of secondary immunosuppression. The proposed mechanism of action of these products is macrophage activation and subsequent release of cytokines that enhance humoral and cell-mediated immunity. In equine medicine, nonspecific immunostimulant products are used for prevention and treatment of infectious respiratory disease and treatment of s...
Giguère S, Prescott JF.The remarkable ability of the horse and other animals to prevent infection by most bacterial pathogens encountered is the result of a complex set of distinct but overlapping defense mechanisms. This article summarizes the current state of knowledge on innate and adaptive immunity to bacterial pathogens and reviews various ways in which some bacteria have evolved in order to evade components of the host response.
MacKay RJ.After inflammation is initiated by detection of antigen, plasma components and activated leukocytes are concentrated at the inflammatory site. Cellular and chemical effectors of inflammation are focused on the offending antigen, usually resulting in its destruction and elimination. Activation of endogenous counter-regulatory systems damps down the inflammatory process and is the first stage of repair. In addition to local effects, the inflammatory focus may initiate a continuum of systemic acute phase responses ranging from the systemic inflammatory response syndrome (SIRS) to generalized immu...
Gibson JS, Cossins AR, Ellory JC.Oxygen is essential for all higher forms of animal life. It is required for oxidative phosphorylation, which forms the bulk of the energy supply of most animals. In many vertebrates, transport of O(2) from respiratory to other tissues, and of CO(2) in the opposite direction, involves red cells. These are highly specialised, adapted for their respiratory function. Intracellular haemoglobin, carbonic anhydrase and the membrane anion exchanger (AE1) increase the effective O(2)- and CO(2)-carrying capacity of red cells by approximately 100-fold. O(2) also has a pathological role. It is a very reac...
Corvilain B, Collyn L, van Sande J, Dumont JE.The regulation of thyroid metabolism by iodide involves numerous inhibitory effects. However, in unstimulated dog thyroid slices, a small inconstant stimulatory effect of iodide on H(2)O(2) generation is observed. The only other stimulatory effect reported with iodide is on [1-(14)C]glucose oxidation, i.e., on the pentose phosphate pathway. Because we have recently demonstrated that the pentose phosphate pathway is controlled by H(2)O(2) generation, we study here the effect of iodide on basal H(2)O(2) generation in thyroid slices from several species. Our data show that in sheep, pig, bovine, ...
Bird JL, May S, Bayliss MT.Arthroses are debilitating diseases of articular joints which result in erosion of the cartilage extracellular matrix. Nitric oxide (NO) is a major component of the inflammatory response, and has been implicated as a mediator of some of the effects of the proinflammatory cytokine, interleukin-1 (IL-1). In this study, we investigated the role of NO in the regulation of proteoglycan degradation in equine articular cartilage. NO fully mediated the suppressive effect of IL-1 on proteoglycan synthesis. However, NO was also antagonistic to proteoglycan degradation, irrespective of whether degradatio...
Gastal EL, Donadeu FX, Gastal MO, Ginther OJ.The echotextural changes occurring in the follicular wall in association with deviation in diameters were studied in 8 pony mares. Echotextural changes could be useful as a reference point for future studies of the follicle-selection phenomenon. Follicles were examined daily by transrectal ultrasound from 3 d before to 3 d after the beginning of deviation (Day 0). The following echotextural end points were recorded based on a scoring or percentage system: 1) thickness of granulosa, 2) echogenicity of granulosa, 3) prominence of an anechoic layer located beneath the granulosa, and 4) extent of ...
Flores M, Wajnberg E, Bemski G.Electron nuclear double resonance (ENDOR) spectroscopy has been used to study protons in nitrosyl horse heart myoglobin (MbNO). (1)H ENDOR spectra were recorded for different settings of the magnetic field. Detailed analysis of the ENDOR powder spectra, using computer simulation, based on the "orientation-selection" principle, leads to the identification of the available protons in the heme pocket. We observe hyperfine interactions of the N(HisF8)-Fe(2+)-N(NO) complex with five protons in axial and with eight protons in the rhombic symmetry along different orientations, including those of the ...
Dobrinski I, Jacob JR, Tennant BC, Ball BA.Equine oviductal epithelial cells (OEC) were transformed with simian virus 40 large T antigen (SV 40 T-ag) to create a cell line for the study of the interaction of equine spermatozoa with oviductal epithelium. One cell line was established based on the expression of the SV 40 T-ag and extended lifespan in culture. Immortalized equine OEC retained the characteristics of differentiated OEC such as the formation of monolayers with characteristic epithelial morphology and cell polarization as well as expression of cytokeratin and equine major histocompatibility complex I. Monolayers of immortaliz...
Moczygemba C, Guidry J, Wittung-Stafshede P.Native myoglobin (Mb) consists of two populations which differ in the orientation of the heme by 180 degrees rotation (as verified by nuclear magnetic resonance) but have identical absorption spectra and equilibrium-thermodynamic stability. Here, we report that these two fractions of native oxidized Mb (from horse) both unfold and refold (chemical denaturant, pH 7, 20 degrees C) in two parallel kinetic reactions with rate constants differing 10-fold. In accord, the oxidized heme remains coordinated to unfolded horse Mb in up to 4 M guanidine hydrochloride (pH 7, 20 degrees C).
Liberda J, Tichá M, Zralý Z, Svecová D, Vezník Z.The interaction of seminal plasma proteins, sperms and detergent-released sperm proteins of three species with different types of acidic polysaccharides was studied. Heparin-binding activity of boar, bull and stallion seminal plasma proteins, sperms and sperm proteins was compared with their ability to interact with polysaccharides differing in the presence of the sulfate groups or in their saccharide moiety (chondroitin sulfate, dextran sulfate, fucoidan, hyaluronic acid). Bull seminal plasma proteins were characterized by higher affinity to heparin, fucoidan and dextran sulfate, while signif...
Merkies K, Buhr MM.Spermatozoal function is affected by the ability to regulate intracellular calcium concentrations ([Ca2+]i), and may be influenced by epididymal maturation as well as environmental components. Regulation of [Ca2+]i in ejaculated and epididymal stallion spermatozoa was monitored over time in various media. Spermatozoa from each of 5 pony stallions (3 ejaculate samples and 1 caput and cauda sample) were labeled with the fluorescent calcium indicator probe Indo-1 in a calcium-free modified Tyrode's buffer. Fluorescent emissions were monitored by a dual wavelength spectrofluorometer over 5 h. Calc...
Provitera P, Bouamr F, Murray D, Carter C, Scarlata S.Human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) are closely related lentiviruses that infect immune cells, but their pathogenesis differ. Localization to the cytosolic leaflet of the plasma membrane is critical for replication of both viruses. This localization is accomplished through the matrix (MA) domain of the Gag precursor protein. In HIV-1, association of MA to anionic membranes appears to be primarily driven by a linear cluster of basic residues in the MA domain and an N-myristoylation signal. Interestingly, the MA protein of EIAV does not contain either of ...
Molenkamp R, Rozier BC, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the type member of the family Arteriviridae, is a single-stranded RNA virus with a positive-stranded genome of approximately 13 kb. EAV uses a discontinuous transcription mechanism to produce a nested set of six subgenomic mRNAs from which its structural genes are expressed. We have generated the first documented arterivirus defective interfering (DI) RNAs by serial undiluted passaging of a wild-type EAV stock in BHK-21 cells. A cDNA copy of the smallest DI RNA (5.6 kb) was cloned. Upon transfection into EAV-infected BHK-21 cells, transcripts derived from this clo...
Aggarwal N, Holmes MA.Despite the importance of IgG Fc receptors in the regulation of various immunological mechanisms, these receptors have not been well characterised in the domesticated animals including equines. This paper describes the production of two monoclonal antibodies (CVS 59 and CVS 61) that recognise equine IgG Fc receptors. Fusions were conducted using BALB/c mice hyperimmunised with equine peripheral blood mononuclear cells. Hybridoma supernatants were screened on the basis of their ability to inhibit the rosetting of equine antibody coated sheep erythrocytes with equine peripheral blood mononuclear...
Fernandez CJ, Scott DW, Erb HN.A retrospective study was performed on skin biopsy specimens from horses and cats having eosinophilic granulomas with 'collagen degeneration', eosinophilic skin diseases without 'collagen degeneration' and pyogranulomas without 'collagen degeneration'. Neither the appearance of collagen fibres nor the dominant polymorphonuclear cells, as seen in H & E-stained sections, were predictive of Masson's trichrome findings. Hence, a Masson's trichrome staining abnormality of collagen fibres was no more likely to be present in lesions with 'collagen degeneration' than in those lesions without 'coll...
Siedek EM, Honnah-Symns N, Fincham SC, Mayall S, Hamblin AS.Monoclonal antibodies (mAbs) recognizing equine macrophages are scarce. The present study compared the immunocytochemical staining of various equine tissues (lymphoid tissue, lung, liver, small intestine, skin and blood leucocytes) by an antibody, Ki-M6, which detects CD68 in human macrophages and dendritic cells, and by a new anti-equine mAb, JB10, with staining produced by two previously described anti-equine macrophage mAbs, CZ2.2 and CZ3.3. Ki-M6 was shown to identify equine macrophages, which had a distribution different from those identified by CZ2.2 and CZ3.3. JB10 identified equine mac...
McKane SA, Slocombe RF.Six horses, free of recent exercise-induced pulmonary haemorrhage (EIPH), each had 8 bronchial segments inoculated with 40 ml of autologous blood lavaged on Days 3, 5, 7, 10, 14 and 21 after inoculation. The bronchoalveolar lavage (BAL) fluid samples were analysed, and total leucocyte counts and differential cell percentages determined. Statistical analysis of the differences between the 8 post inoculation and 1 pre-inoculation (control) lavage sites demonstrated an early neutrophilic response, rising from < 5% of alveolar leucocytes to 10% by 24-48 h post inoculation. As this response wane...
Wille KH, Nakov C.The mucous membrane of the caecum and colon ascendens of adult horses was first studied using light and transmission electron microscopy. In the surface epithelium there was an inconspicuous constellation of organelles, otherwise there was a lot of mitochondria as a source of energy for absorptive performances. Moreover, enlarged intercellular spaces exist as an indication of an increased uptake of water and electrolytes. In the basal region of Lieberkühn's crypts there were single enteroendocrine cells and numerous granules in the apical epithelial cytoplasm. The functional meaning of these ...
Miller CB, Wilson DA, Keegan KG, Kreeger JM, Adelstein EH, Ganjam VK.To determine if there is a difference in in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. To determine the effects of a corticosteroid and monokine on in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. Methods: Growth of fibroblasts from tissues harvested from the trunk and limb were compared from horse and pony samples grown in control media and control media with triamcinolone or monokine added. Methods: Dermal and subcutaneous tissue from 22 horses and 17 ponies of various ages ...
Svistunenko DA, Sharpe MA, Nicholls P, Wilson MT, Cooper CE.A new method of EPR spectral analysis is developed to quantitate overlapping signals. The method requires double integration of a number of spectra containing the signals in different proportions and the subsequent solution of a system of linear equations. The result gives the double integral values of the individual lines, which can then be further used to find the concentrations of all the paramagnetic species present. There is no requirement to deconvolute the whole spectrum into its individual components. The method is employed to quantify different heme species in methemoglobin and metmyo...
Abd-Elnaeim MM, Derar IR, Wilsher S, Allen WR, Leiser R, Schuler G.The functions of placental oestrogens during equine pregnancy are still unclear. Yet, they may act predominantly as local regulators of growth and differentiation in the microplacentomes. Thus, expression patterns of oestrogen receptors (ERs) alpha and beta were investigated in the microcotyledonary placenta from pregnant mares at 110, 121, 179, 199 and 309 days of gestation by immunohistochemistry. In microplacentomes, both the ER isoforms were detected in trophoblast (T) cells, chorionic villous stroma (FS), microcaruncular epithelium (ME) and microcaruncular stroma (MS). Proportions of posi...
Bell SC, Savidge C, Taylor P, Knottenbelt DC, Carter SD.A putative immunodeficiency, causing mortality in UK Fell pony foals (Fell pony syndrome), was studied in affected foals and compared with healthy, age-matched foals. Differential cell counts of peripheral blood indicated that the syndrome foals were lymphopenic (P<0.05). Flow cytometric analysis of circulating leucocytes showed a reduced MHC II expression (P<0.01) on lymphocytes but not on polymorphonuclear cells in affected foals. There were no changes in the percentages of CD4+ or CD8+ T cells. There was an increased (P<0.05) expression of CD11a/18 by the lymphocytes of the syndrom...
Salinas C, Barriga K, Albornoz A, Alarcon P, Quiroga J, Uberti B, Sarmiento J, Henriquez C, Ehrenfeld P, Burgos RA, Moran G.Neutrophils display an array of biological functions including the formation of neutrophil extracellular traps (NETs), web-like structures specialized in trapping, neutralizing, killing and preventing microbial dissemination within the host. However, NETs contribute to a number of inflammatory pathologies, including severe equine asthma. Tamoxifen (TX) is a selective estrogen receptor modulator which belongs to the triphenylethyllenes group of molecules, and which is used as a treatment in all stages of estrogen-positive human breast cancer. Our previous results suggest that tamoxifen can modu...
Seethanathan P, Bottoms GD, Schafer K.Direct effects of endotoxin (lipopolysaccharide [LPS]) on equine WBC are known to stimulate the release of a variety of mediators including thromboxane, prostacyclin, and leukotrienes. In this study, 0.1 microgram of LPS/ml stimulated an early increase in tumor necrosis factor, succeeded by an increase in interleukin-1, but concentrations of LPS up to 5.0 micrograms/ml caused no significant increase in superoxide anion release. The concentration of LPS (0.1 microgram/ml) used in this experiment was in the range of concentrations measured in plasma of some horses with gastrointestinal problems....
Jenner F, van Osch GJ, Weninger W, Geyer S, Stout T, van Weeren R, Brama P.Articular cartilage regeneration is the focus and goal of considerable research effort. Since articular chondrocytes descend from a distinct cohort of progenitor cells located in embryonic nascent joints (interzones), establishing the timing of equine interzone formation is an essential first step towards understanding equine joint and articular cartilage development. Objective: To establish the time frame during which the equine femorotibial interzone forms. Methods: Descriptive anatomical study. Methods: Equine embryos were harvested at 37 (E37), 40, 42, 45, 50 and 65 days' gestation. The fe...
Piuko K, Bravo IG, Müller M.In the present study we describe the isolation and characterization of putative equine granzyme B for which we propose the designation 'eqGrzmB'. Sequence analysis revealed characteristic features of a GrzmB protease such as the presence of a signal (leader-) peptide and an activation di-peptide. The isolated eqGrzmB is functionally active when expressed in human or in insect cells. Furthermore, exchange of any of three putative active site amino acids, which are highly conserved along granzyme B enzymes, led to a complete loss of enzymatic activity in the newly identified eqGrzmB. Phylogeneti...
Sandersen C, Mouithys-Mickalad A, de la Rebière G, Deby G, Serteyn D, Franck T.To investigate the effect of acepromazine (ACP) on reactive oxygen species (ROS) production by stimulated equine neutrophils. Methods: Ex vivo biochemical experiments. Methods: Isolated neutrophils from healthy untreated horses. Methods: Neutrophils were incubated with ACP at concentrations of 10(-4), 10(-5) or 10(-6) M and then stimulated with phorbol-myristate-acetate (PMA) before measurement of lucigenin-enhanced chemiluminescence (CL). In a second experiment neutrophils were incubated in the presence of α-keto-γ methylthiobutyric acid (KMB) and treated with ACP at concentrations of 10(-4...
Medica AJ, Gibb Z, Sheridan A, Harrison N, Aitken RJ.MTT is a commonly used cell vitality probe, due to its ability to form insoluble formazan deposits at cellular locations of intense oxidoreductase activity. Although this response is considered a reflection of mitochondrial redox activity, extra-mitochondrial sites of MTT reduction have been recognized within the spermatozoa of several mammalian species. Therefore, the aim of this study was to determine the major sites and causative mechanisms of MTT reduction in stallion spermatozoa. Our results show that stallion spermatozoa displayed substantial mitochondrial formazan deposition, as well as...
Ceusters JD, Serteyn DA, Minguet G, de la Rebière de Pouyade G, Romainville J, Deby-Dupont GP, Mouithys-Mickalad AA, Franck TJ.Horses are particularly sensitive and exposed to excessive inflammatory responses evolving toward an important stimulation of polymorphonuclear neutrophils (PMNs). The aim of this work was to stimulate equine neutrophils in whole blood and to evaluate their response by measuring the release of total and active myeloperoxidase (MPO) and total elastase, considered as markers of neutrophil stimulation and degranulation. Because of the critical importance of the concomitant presence of LPS and TNF-α in equine pathological situations, we combined these two natural mediators to stimulate PMN and co...
Ortiz I, Felix M, Resende H, Ramírez-Agámez L, Love CC, Hinrichs K.To define the effect of sperm agglutination, associated with incubation under capacitating conditions, on accuracy of membrane assessment via flow cytometry and to develop methods to mitigate that effect. Methods: Sperm motility was measured by CASA. Sperm were stained with PI-PSA or a novel method, LD-PSA, using fixable live/dead stain and cell dissociation treatment, before flow-cytometric analysis. Using LD-PSA, acrosome reaction and plasma membrane status were determined in equine sperm treated with 10 μm A23187 for 10 min, followed by 0, 1, or 2 h incubation in capacitating conditions. R...
Goudet G, Belin F, Młodawska W, Bézard J.The effect of epidermal growth factor (EGF) on the in vitro maturation rate of equine oocytes was examined. Oocytes were collected from an abattoir (Expt 1) or using ultrasound-guided follicular puncture in vivo (Expt 2). All oocytes with a compact or expanded cumulus at recovery were cultured for 30 h in: medium 1 (TCM199 + fetal calf serum (FCS) + crude equine gonadotrophin (CEG) + oestradiol + antibiotics); medium 2 (TCM199 + EGF); medium 3 (medium 1 without FCS + EGF); or medium 4 (medium 1 without CEG + EGF). In Expt 1, 84% (37/44) and 87% (40/46) cumulus expansion (P > 0.05), and 39% ...
Milne EM, Fintl C, Hudson NP, Pearson GT, Mayhew IG, Hahn CN.This paper describes the histopathological and immunohistochemical changes in the central, autonomic and enteric nervous systems in a well-documented case of equine dysautonomia (ED), after the animal had recovered without significant residual clinical signs. Evidence of neuronal degeneration, such as neuronal chromatolysis, glial scars or a decrease in density of neurons, was not observed in the midbrain, pons, medulla oblongata or spinal cord, including the nuclei of cranial nerves III, V, VII, X and XII. In addition, no evidence of muscle denervation or re-innervation, such as group atrophy...
Figueroa RJ, Koch TG, Betts DH.To investigate the osteogenic differentiation potential of equine umbilical cord blood-derived multipotent mesenchymal stromal cells (CB-MSC) within coralline hydroxyapatite scaffolds cultured in osteogenic induction culture medium. Methods: Scaffolds seeded with equine CB-MSC were cultured in cell expansion culture medium (control) or osteogenic induction medium (treatment). Cell viability and distribution were confirmed by the MTT cell viability assay and DAPI nuclear fluorescence staining, respectively. Osteogenic differentiation was evaluated after 10 days using reverse transcription polym...
Srivastava SK, Barnum DA.Streptococcus equi was found to adhere to tongue, cheek and nasal epithelial cells of ponies, in vitro. Maximum adherence was observed at pH 7.5 after one hour of incubation of bacteria with epithelial cells. This adherence was more on epithelial cells from adult animals than from foals. Streptococci exposed to heat (60 degrees C for 10 min) or treated with pepsin or trypsin showed a reduced adherence, whereas an increase occurred on treatment with hyaluronidase. Antibodies against whole S. equi cells or M-like protein blocked the adherence, whereas antibodies against group-specific carbohydra...
Thorsteinsdóttir L, Torsteinsdóttir S, Svansson V.Due to the slow growth of equine gammaherpesviruses, isolation of these viruses requires cells that can be propagated long term and show clear cytopathy following infection. Equine cell lines with extended lifespan were established from primary cells originating from equine fetal kidney and lung by transfecting the cells with the retroviral vector LXSN116E6E7 containing the human papilloma virus oncogenes 16 E6 and E7. The transfected equine kidney cell line and equine lung cell line can be propagated for more than 40 passages, whereas the corresponding primary cells only for 10-12 passages. T...
Mifune H, Richter R, Forssmann WG.The distribution of immunoreactivity (IR) for cardiodilatin/atrial natriuretic peptide (CDD/ANP) and brain natriuretic peptide (BNP) was examined immunohistochemically and immuno-electron-microscopically in the equine atrium, using specific antibodies. In the immunohistochemical studies, IR-CDD/ANP and IR-pBNP-26 (porcine BNP-26 immunoreactivity) was detected in the cytoplasm of the auricular cardiocytes, but IR-hBNP-32 (human BNP-32 immunoreactivity) was not. The double immunogold labelling method for IR-hBNP-28 and IR-pBNP-26 revealed that gold particles of different sizes were located in th...
Macleod KD, Scott DW, Erb HN.A retrospective study was performed to assess the prevalence of apoptotic epidermal keratinocytes in biopsy specimens from 226 horses with inflammatory dermatoses and from 27 normal specimens. One or more apoptotic keratinocytes were found in specimens from 28 of 226 (12%) horses with various dermatoses, and in one of 27 (4%) specimens from normal horses. The prevalence (proportion of cases with apoptotic epidermal keratinocytes) of apoptotic keratinocytes in the group composed of discoid lupus erythematosus, erythema multiforme, photodermatitis, and systemic lupus erythematosus was significan...
Schumacher J, Spano JS, Moll HD.Peritoneal fluid was collected from 15 clinically normal horses and was analyzed for nucleated cell (NC) counts and specific gravity. Six horses (controls, group 1) were subjected to abdominocentesis only, with a teat cannula, every 24 hours for 5 days. There were no marked changes in the peritoneal fluid of these horses over the 5-day period. Peritoneal fluid was collected from 6 other horses (group 2) with an 8.89-cm 18-gauge needle. The needle was then advanced until intestinal fluid was obtained. Peritoneal fluid was then collected with teat cannulas at 24-hour intervals for an additional ...
Jeffrey SC, Murray MJ, Eichorn ES.Growth factors are important in healing and restoration of injured gastrointestinal tissues and, therefore, we characterised temporally the distribution and density of epidermal growth factor receptor (EGFr) in normal and peptic-injured gastric squamous epithelium of horses. Lesions were induced in the equine gastric squamous epithelium using a feed deprivation protocol that results in prolonged increased gastric acidity. Fifteen mature horses, 9 geldings and 6 mares, age 3 to 20 years, were used and divided into 3 groups: Group 1 (n = 5) were subjected to euthanasia for problems unrelated to ...
May SA, Hooke RE, Lees P.Prostaglandin E2 (PGE2) and stromelysin are produced by equine chondrocytes and synovial cells in vitro in response to recombinant human (rh) interleukin-1 (IL-1) alpha and beta, and equine mononuclear cell supernatants (MCS) containing IL-1. However, culture conditions are important. PGE2 concentrations increase in proportion to the concentration of fetal calf serum (FCS) in the culture medium, whereas stromelysin concentrations are inversely proportional to the concentration of FCS. Equine MCS, containing a lower concentration of IL-1 than the concentration of rhIL-1 used in these experiment...
Frean SP, Bryant CE, Fröling IL, Elliott J, Lees P.Recent research in several species has suggested nitric oxide (NO) as a mediator of articular cartilage damage and an inhibitor of cartilage matrix neosynthesis. This study investigated NO production by cultured equine articular chondrocytes in response to 2 arthritogenic molecules, namely lipopolysaccharide (LPS) and interleukin-1 beta (IL-1 beta), and compared NO production by cultured equine synoviocytes stimulated with LPS. Synoviocytes exhibited a low basal level of NO synthesis (measured as nitrite, a NO metabolite) that was neither significantly increased nor decreased by exposure to LP...
Henderson LL, Warren JC.Estradiol 17 alpha-dehydrogenase (EC 1.1.1.148) and estradiol 17 beta-dehydrogenase (EC 1.1.1.62) from horse placenta have been purified to homogeneity. Both enzymes are localized in the microsomal fraction and are solubilized in 1.5% sodium cholate. The 17 alpha- and 17 beta-dehydrogenases are separated by selective elution from hydroxylapatite with 0.5 and 1.0 M potassium phosphate, respectively. Subsequent purification is achieved by two affinity-absorption steps using reactive blue 2-agarose and estriol hemisuccinate-Sepharose. Homogeneous estradiol 17 alpha-dehydrogenase has a specific ac...
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 (...
Spiers S, May SA, Harrison LJ, Bennett D, Edwards GB.Significant amounts of collagenase and caseinase activity were detected in infected synovial fluid samples. Partial characterisation of the enzymes by gel filtration suggested that synovial fluid from cases of infectious arthritis may contain enzymes from both the synovial cells and neutrophils. This finding was also supported by analysis of sequential synovial fluid samples from 4 infected joints. In 3 joints the concentration of caseinase and in 1 joint collagenase paralleled the decline in total nucleated cell count. However, in 3 joints the concentration of collagenase remained high after ...
Pereira BC, Ortiz I, Dorado J, Consuegra C, Diaz-Jimenez M, Demyda-Peyras S, Gosalvez J, Hidalgo M.DNA fragmentation of granulosa cells might be related to developmental competence of the equine oocyte. Granulosa cells are commonly stored before DNA fragmentation assessment, but the effect of preservation methods on this parameter remains unexplored. The aim of this study was to evaluate whether or not cryopreservation of granulosa cells affects the DNA damage. Equine oocytes were recovered from postmortem ovaries of five mares. Granulosa cells were washed by centrifugation and then analyzed (control) or stored in cryovials following four different protocols: P1 = directly plunged in liqui...
Kumar P, Timoney JF.The tubal tonsil of the horse surrounds the pharyngeal opening of the eustachian tube and is lined by pseudostratified columnar ciliated epithelium interspersed with areas of follicle-associated epithelium (FAE) heavily infiltrated by lymphocytes but devoid of goblet and ciliated cells. Scanning and transmission electron microscopy revealed microvillous cells and cells with features characteristic of M cells such as reduced microvilli or depressed bare surface, more numerous mitochondria, small vesicles and lysosomes, as well as vimentin filaments and epitopes specific for GS 1-B4 as previousl...
Mathes RL, Reber AJ, Hurley DJ, Dietrich UM.To evaluate the effects of topical antifungal drugs and delivery vehicles on the morphology and proliferation rate of cultured equine keratocytes. Methods: 16 corneas obtained from 8 apparently ophthalmologically normal horses < 0.5 hours after euthanasia for reasons unrelated to the study. Methods: Primary cultures of equine keratocytes were obtained from corneal stroma and were exposed to several concentrations of 3 commonly used, topically applied antifungals: natamycin, itraconazole, and miconazole. In addition, effects of drug delivery vehicles DMSO, benzalkonium chloride, and carboxym...
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...
Cohen L, Bousfield GR, Ben-Menahem D.The pituitary LHβ and placental CGβ subunits are products of different genes in primates. The major structural difference between the two subunits is in the carboxy-terminal region, where the short carboxyl sequence of hLHβ is replaced by a longer O-glycosylated carboxy-terminal peptide in hCGβ. In association with this structural deviation, there are marked differences in the secretion kinetics and polarized routing of the two subunits. In equids, however, the CGβ and LHβ subunits are products of the same gene expressed in the placenta and pituitary (LHβ), and both contain a carboxy-te...
Baker JM, Bamford AI, Carlson ML, Mcculloch CE, Antczak DF.A cytotoxic T-lymphocyte assay was used to determine whether equine chorionic girdle cells are susceptible to lysis by CD8+ cytotoxic T cells primed in vitro against allogeneic lymphocytes. Classical cytotoxic T-lymphocyte activity against fresh or cultured trophoblast targets was demonstrated using peripheral blood lymphocytes from nonpregnant mares. Lysis of allogeneic (horse) and xenogeneic (donkey) lymphocyte targets was used as a control for trophoblast lysis. The major histocompatibility complex (MHC) class I specificity of the cytotoxic T-lymphocyte reactions was determined using panels...
