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.
Nishita T, Matsushita H.Sections of equine thymus were examined for the presence of carbonic anhydrase (CA) isozymes by an immunohistochemical method. Carbonic anhydrase III, a major enzyme of skeletal muscle, was localized in some of the epithelial-reticular cells of the equine thymus. This finding suggests the presence of a new type of cell in the thymic cortex. The concentration of CA-III in the thymus was 17 micrograms/g wet tissue. CA-I and CA-II were not found in equine thymus.
Valpotić I, Kastelan M, Rudolf M, Gerencer M, Jukić B, Basić I.The percentage of T and B lymphocytes in the peripheral blood of horses chronically infected with equine infectious anaemia (EIA) virus was determined and the results were compared with the percentage of these cells in healthy uninfected horses. Cells with membrane receptors for sheep erythrocytes (T and active T lymphocytes) were determined by E and A rosette techniques, while cells with receptors for the C3b component of complement and those with receptors for mouse erythrocytes (B lymphocytes), were determined by the EAC rosette method. The percentage of Fe positive cells was assayed by the...
Derksen FJ, Brown CM, Sonea I, Darien BJ, Robinson NE.Comparisons were made between transtracheal aspirate (TTA) and bronchoalveolar lavage (BAL) cytology obtained from 50 horses with chronic lung disease and from 10 control horses. There was no significant correlation between the TTA cytology and the BAL cytology, suggesting that the cell population in the trachea is not representative of the cell population in the lower airways. In control horses the range of differential cell counts obtained from TTA fluid was remarkably large, whereas the variability in cell populations observed in BAL fluid was smaller. In the principal horses the total and ...
Melrose PA, Knigge KM.The present study describes the topography of immunoreactive (ir) oxytocin (OXY) and vasopressin (AVP) neurons in the forebrain of Equus caballus and the coexistence of ir proopiomelanocortin (POMC)-derived peptides in the same cells. These data are compared to those for other mammalian species and the possible significance of species variations is considered. As expected, magnocellular neurons of the equine hypothalamus, which contain ir OXY or AVP, have prominent discernible projections to the neurohypophysis. Further, as in other mammalian species, the field of ir OXY perikarya generally ex...
Auer DE.The role of oxygen-derived free radicals is considered critical to the etio-pathogenesis of equine inflammatory joint disease. In vivo, the superoxide radical in the joint may be derived either from activated polymorphonuclear leukocytes or from an ischemia/reperfusion cycle. In the presence of ferrous iron, it may generate the highly reactive hydroxyl radical (OH *). Predisposing factors may include synovitis, exercise-induced ischemia and minor traumatic injury to the joints. Unlike other inflammatory mediators, oxygen-derived free radicals may damage tissue directly and these reactive speci...
Bianchi M.In 13 horses from both sexes, between 5 months and 18 years of age, in good nutritional state, statistical evaluations of fat cell sizes were performed in 16 body regions. From direct and indirect measurements referred to the cell diameter and cell number in equivalent areas, carried out on sections from paraffin embedded material and on preparations of dissociated whole cells, it emerged that the adipose cells of the subserous fat of the abdominal floor are consistently the largest, whereas those of the orbital fat body and supraorbital fossa are the smallest. In the other regions the cells h...
López ML, Grez P, Gribbel I, Bustos-Obregón E.The epididymis of stallion castrated during the breeding and non breeding seasons were subdivided into six regions and their ultrastructural and cytochemical characteristics were studied in order to provide a better understanding of the structure-function relationship of this androgen target organ. Even when the stallion has been postulated to be a seasonal breeder, our results do not show significant ultrastructural or cytochemical differences in both seasons. The pseudostratified epithelium is composed mainly of principal and basal cells and intraepithelial lymphocytes. The principal cells s...
Tajima M, Araiso T, Koyama T, Fujinaga T, Otomo K, Koike T.The membrane viscosity of peripheral blood lymphocytes (PBLs) of equine, bovine and canine was measured by the use of time-resolved fluorescence depolarization technique with 1, 6-diphenyl-1,3,5-hexatriene (DPH). The viscosity values were 0.55, 0.59 and 0.50 poise for equine, bovine and canine PBLs, respectively. These values were compared with steady-state anisotropies and order parameters measured from electron spin resonance (ESR) of 5-doxyl stearic acid. Both values were increased with increase of viscosity. The fluid property of the membranes stimulated with phytohemagglutinin-P (PHA) was...
Cecio A, Vittoria A.Amines and/or peptide-producing cells, deserving to be called paraneurons, were demonstrated in the urethro-prostatic complex of the man, rabbit, buffalo and sheep and in the uterine horns of the pig, horse and mouse, by means of histochemical, immunohistochemical, immunofluorescent and double labeling immunofluorescent techniques. In particular, the urethro-prostatic complex of the sheep contains cells producing serotonin, chromogranin A and somatostatin. Often the amine and the "marker"-protein were colocalized in the same cells. Chromogranin A- and somatostatin-containing cells were found i...
Weiss DJ, Kraemer R, Schmit K.A simple discontinuous Percoll density-gradient technique was adapted for isolation of granulocytes and mononuclear cells from cats, dogs, horses and cattle. Separation was accomplished at low speeds using a standard tabletop centrifuge. Cell purity was 100% for both granulocytes and mononuclear cells and cell viability exceeded 95%. Percent recovery of leukocytes ranged from 69 to 83%.
Björkman C.1. Comparative data are presented of the activities of pyruvate dehydrogenase complex and acetyl-CoA synthetase and of the acetate content in homogenates from ventral grey matter in spinal cord from cows and two non-ruminant species, pigs and horses. The methods used in the study are evaluated and discussed. 2. The total pyruvate dehydrogenase complex activity was 24.9-29.9 mU/mg protein and did not differ between the species. The part of the complex that was in active form at the sampling occasion was 60, 85 and 95% in cows, pigs and horses, respectively. 3. Acetyl-CoA synthetase activity dif...
Schuetz AW, Whittingham DG, Legg RF.Granulosa cells at different stages of differentiation were collected from ovarian follicles and oviducts during the periovulatory period, and their nuclear DNA content was monitored by flow cytometry to establish their cell cycle characteristics (G0 + G1, S, G2 + M). The proportion of cells in the three phases of the cell cycle varied in characteristics patterns depending upon the time they were collected, before or following ovulation. Granulosa (cumulus) cells recovered from ovulated oocytes were mitotically inactive as shown by the large proportion of cells with a 2C amount of DNA and the ...
Dennis VA, Klei TR, Chapman MR, Jeffers GW.Eosinophils and neutrophils from ponies with Strongylus vulgaris-induced eosinophilia (eosinophilic ponies; activated eosinophils and neutrophils) were assayed in vitro for chemotactic and chemokinetic responses to zymosan-activated serum (ZAS) using the filter system in Boyden chambers, for Fc and complement (C) receptors using the EA and EAC-rosette assays, respectively, and for phagocytic and bactericidal activities using opsonized Escherichia coli and the acridine orange method. The responses of activated eosinophils and neutrophils in the above assays were compared with those of eosinophi...
Jacob RJ, Steiner MR.Equine herpesvirus 3 (EHV-3)-infected equine cells display a kinetics of infected cell polypeptide (ICP) synthesis at 34 degrees C that is typical of coordinate cascade gene regulation of herpesviruses. In contrast, when infected cell cultures are incubated at the restricted temperature of 39 degrees C, the shift from early (beta) gene expression to late (gamma) gene expression is perturbed, i.e., there is an accumulation of early (beta) gene products and a decrease in, or absence of, late (gamma) gene products. Some of the affected late (gamma) gene products may be glycoproteins since these I...
Kayar SR, Hoppeler H, Mermod L, Weibel ER.Individual mitochondria were reconstructed from ultrathin serial sections of selected muscle fibers in the M. semitendinosus of a horse, over a length of nearly two sarcomeres. Mitochondria were found to be highly variable, with size and complexity of single mitochondria increasing with the fractional part of a fiber occupied by mitochondria. In fibers with a mitochondrial volume density of less than 4%, corresponding to the mitochondrial content of fast-twitch glycolytic fibers, mitochondria were generally rather simple cylindrical shapes, oriented parallel to the myofibrils. In fibers with a...
Pycock JF, Allen WE.The neutrophil is involved in the defence of the mare's uterus against micro-organisms. The ability of Streptococcus zooepidemicus and its growth products to induce shape changes or directional locomotion (chemotaxis) of equine neutrophils was investigated; no effect was found.
Watson ED, Stokes CR.Immunoglobulins A, G and M were localised by immunoperoxidase staining of endometrial sections from ovariectomised mares. Treatment with progesterone or oestradiol-17 beta did not significantly affect numbers of cells secreting any of the isotypes. Mares with persistent endometritis did not have significantly greater numbers of endometrial plasma cells than genitally-normal mares.
Cummings JF, Fubini SL, Todhunter RJ.Digital neurectomies, performed to relieve pain and lameness, are often complicated postoperatively by formation of painful neuromas. In this study attempts were made to deliver lethal doses of neurotoxin to the cell bodies of the transected digital nerve fibres via long-distance retrograde axon transport and, thereby, prevent the regenerative changes that lead to neuroma formation. After applying doxorubicin in various ways to the digital nerve stumps of ponies, degenerating or necrotic neurones appeared only sporadically in the spinal ganglia. Although doxorubicin was largely ineffective in ...
Henry MM, Moore JN.Increasing evidence has demonstrated the importance of monocyte procoagulant activity (PCA) in the pathogenesis of coagulopathies in a variety of diseases. Because endotoxin precipitated coagulopathies are common sequelae to intestinal ischemia/endotoxemia in the equine species, we investigated the ability of equine peripheral blood monocytes to express PCA. Monocytes isolated from five healthy adult horses were incubated in vitro with Escherichia coli endotoxin (10 micrograms), and the PCA was measured by the ability of cellular lysates to accelerate the clotting times of equine plasma in a m...
Kelly CM, Hoyer PB, Wise ME.Dispersed horse luteal cells were used to evaluate the ability of horse LH, hCG and PMSG to stimulate progesterone secretion in vitro. Morphological characterization of these cells before gonadotrophin stimulation indicated the presence of two populations of cells based on cell diameters. In luteal cells incubated as suspended cells, horse LH and hCG stimulated (P less than or equal to 0.05) progesterone production at all levels of treatment. Stimulation of progesterone secretion by hCG was greater (P less than or equal to 0.05) than by horse LH over the range of concentrations utilized. When ...
Johnson GC, Kohn CW, Johnson CW, Garry F, Scott D, Martin S.Ultrastructural examination of a mechanobullous disease of probable hereditary nature in Belgian foals, confirmed light microscopic findings that separation of the dermo-epidermal junction occurred through the lamina lucida of the basement membrane, leaving the intact lamina densa adherent to the dermis and the plasmalemma of the basal epithelial cells intact. The location of the cleft and the presence of small hemidesmosomes in adjacent intact skin are additional characteristics which make this condition similar to junctional epidermolysis bullosa of man.
Grosenbaugh DA, Amoss MS, Hood DM, Morgan SJ, Williams JD.Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125I-labeled EGF, indicate the presence of a single class of high-affinity binding sites (apparent KD = 2.8 X 10(-11) M), with an estimated maximal binding capacity of 5,800 sites/cell. EGF stimulated [3H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 X 10(-11) M. Likewise...
Adams R, Calderwood-Mays MB, Peyton LC.Three horses were examined for ulcerative pharyngitis, which had been unresponsive to treatment. Biopsy specimens of the pharyngeal lesions were characterized histologically by a mixed population of lymphocytes and histiocytes, suggesting chronic inflammation. Only when biopsy specimens of regional lymph nodes revealed this cell population disrupting the lymph node architecture was the diagnosis of malignant lymphoma made.
May SA, Hooke RE, Lees P.There is increasing evidence that the proteoglycan-degrading neutral metalloproteinase, stromelysin, is a key enzyme in the pathogenesis of osteoarthrosis. Equine synovial lining cells were stimulated in vitro to produce stromelysin, and phenylbutazone, flunixin, betamethasone, sodium hyaluronate and polysulphated glycosaminoglycan (PSGAG) were tested for their ability to inhibit the action of this enzyme on 14C-labelled casein substrate. Only PSGAG possessed inhibitory activity at concentrations likely to be achieved therapeutically in the equine fetlock joint.
Mair TS, Stokes CR, Bourne FJ.An indirect immunoperoxidase technique was used to demonstrate both free immunoglobulin and immunoglobulin-containing plasma cells of IgG, IgA, and IgM classes in the mucosa of the equine respiratory tract. IgA-producing plasma cells predominated in the upper airways, whereas IgG-producing cells predominated in the lower respiratory tract. IgM-secreting cells were uncommon, but present in their highest numbers in the nasopharynx. Plasma cells specific for all of the immunoglobulin classes were identified in the surface epithelium, lamina propria connective tissue, glandular tissue and organise...
Magro AM, Rudofsky UH, Schrader WP, Prendergast J.In vitro IgE-mediated histamine release by equine blood basophils was characterised as the basis for a screening test for immediate hypersensitivity responses in horses. The responses are initiated by inducing agents that are capable of crosslinking or bridging the membrane-bound IgE molecules. The release process is complete within 40 mins. In vitro histamine release is dose-dependent, with a submaximal response at less or greater than the optimal dose of inducing agent. Exogenous calcium is required but not magnesium; the optimal release calcium concentration is 1.0 to 1.5 mM. If an IgE-medi...
Snijder EJ, Ederveen J, Spaan WJ, Weiss M, Horzinek MC.From 380S particles of Berne virus (proposed family Toroviridae) one species of polyadenylated RNA was isolated. Using agarose gel electrophoresis its length was estimated as 20 kb or greater. When assayed under hypertonic transfection conditions genomic RNA was found to be infectious; RNase treatment destroyed the infectivity. The positive polarity of the molecule was confirmed by filter spot hybridization using cDNA prepared against poly(A)-selected RNA from infected cells. In embryonic mule skin cells infected with Berne virus the presence of five virus-specific, polyadenylated RNA species ...
Gopal D, Wilson GS, Earl RA, Cusanovich MA.The ion binding properties of horse, bovine, and tuna cytochrome c (both oxidized and reduced) have been measured using a combination of ultrafiltration, neutron activation, and ion chromatography. The ions investigated were chloride, phosphate, and Tris-cacodylate. Ion chromatography and neutron activation analysis techniques were employed to determine the concentration of free anions. Binding constants are obtained from modified Scatchard plots (in the range of 10-2000 M-1). The redox potentials for cytochrome c at different ionic strengths, pH 7.0, have been determined. In this paper we rep...
de Kok PM, Beijer NA, Buck HM, Sluyterman LA, Meijer EM.The geometry of seven NAD+ analogues bound to horse liver alcohol dehydrogenase (LADH) modified only in their nicotinamide group, have been studied using AMBER molecular mechanics energy-minimization procedures. Starting geometries were taken from X-ray crystallographic data for NAD+/Me2SO/LADH reported by Eklund and co-workers. In this study the NAD+ analogues were encaged by the constituent amino acids of the enzyme within a range of 0.6 nm from the initial NAD+/Me2SO/Zn2+ complex. The calculational method used is able to rationalize individual substituent effects and to evaluate the essenti...
Wichtel MG, Anderson KL, Johnson TV, Nathan U, Smith L.Functional activities (phagocytosis and killing) of neutrophil leucocytes (NL) and immunoglobulin G concentrations were evaluated in six healthy foals from birth to 6 months of age. Peripheral blood NL were reacted with Streptococcus equisimilis in 20 per cent pooled equine serum for 30, 60 and 90 mins and functional activities of NL were determined using a fluorochrome microassay. Values for foal NL function were compared with those of healthy adult horses (n = 28). Foal neutrophil function was influenced by age. Killing capacity of NL decreased, whereas phagocytic capacity increased, until 1...
Wilson DC, Corbett AD, Steel C, Pannirselvam R, Bovell DL.The causal factors of equine anhidrosis have not yet been elucidated but defective electrolyte transport mechanisms in the gland are likely to be involved. To investigate this possibility, experiments were performed on cultured equine sweat gland epithelia from five free-sweating UK horses (3 intact males, 2 mares, aged 2-4 years) and from three free-sweating Singapore horses (1 intact male, 2 mares, aged 3-5 years) and three anhidrotic (Singapore) horses (1 intact male, 1 gelding, 1 mare, aged 3-6 years). Cultured cells from each animal were grown on permeable supports and loaded into Ussing ...
Feughelman M, Lyman DJ, Willis BK.Recent Fourier transform infrared spectroscopy (FTIR) with attenuated total reflection technique (ATR) has been applied to alpha-keratin fibers (horse-hair) extended in water both at 21 and 95 degrees C. Infrared absorption bands in the Amide 1 region indicated that at extensions to 40-50% strain in water at 21 degrees C alpha-helices had completely disappeared and parallel beta-sheets were formed [Appl. Spectrosc. 55 (2001) 552]. However, when the hair fibers were extended to the same strain at 95 degrees C in water the result was the formation of anti-parallel beta-sheets. These results sugg...
Stokes SM, Burns TA, Watts MR, Bertin FR, Stefanovski D, Medina-Torres CE, Belknap JK, van Eps AW.Continuous digital hypothermia (CDH) prevents lamellar failure in the euglycemic hyperinsulinemic clamp (EHC) model of laminitis, but the protective mechanisms are unclear. Objective: To determine if CDH inhibits lamellar inflammatory signaling in the EHC model of laminitis. Methods: Eight Standardbred horses. Methods: Prospective experimental study. Horses underwent an EHC, with 1 forelimb treated with CDH and the other kept at ambient temperature (AMB). Horses were euthanized 48 hours after initiation of the EHC and lamellar tissue was analyzed via polymerase chain reaction (pro-inflammato...
Khatibzadeh SM, Menarim BC, Nichols AEC, Werre SR, Dahlgren LA.Extracellular matrix (ECM) is responsible for tendon strength and elasticity. Healed tendon ECM lacks structural integrity, leading to reinjury. Porcine urinary bladder matrix (UBM) provides a scaffold and source of bioactive proteins to improve tissue healing, but has received limited attention for treating tendon injuries. The objective of this study was to evaluate the ability of UBM to induce matrix organization and tenogenesis using a novel in vitro model. We hypothesized that addition of UBM to tendon ECM hydrogels would improve matrix organization and cell differentiation. Hydrogels se...
Garma-Aviña A.A cytologic study of the choroid plexi of animals and humans was carried out using impression smears (imprints, imp) to understand better the cellular changes that occur in the cerebrospinal fluid in the case of disease. The samples, totaling 756 imp were from 11 dogs (239 imp), 10 horses (219 imp), 1 mule (23 imp), 3 cattle (69 imp), 1 sheep (19 imp), 2 pigs (39 imp), 1 deer (20 imp), 4 monkeys (22 imp), and 7 humans (106 imp). The samples came from individuals clinically free of neurologic disease, as well as from a few abnormal cases. Six of the 7 humans had no history of neurologic disease...
da Silva CMB, Cano FEM, Gaitskell-Phillips G, Vega FJP.Flow cytometry is a powerful tool for the analysis of cell samples formed of multipopulations, such as spermatozoa. In recent years, multiparametric cytometers have evolved, allowing the study of different cellular characteristics, such as protein expression, DNA analysis, or mitochondrial activity. Whether using traditional fluorescent dyes or fluorophore-conjugated antibodies, each cell or cellular component is individually stained, the sample is analyzed at high velocities, and then is displayed and interpreted in a dot-plot. We hereby describe the procedure to perform a multiparametric flo...
Frost ML, Colton SW, Wertz PW, Downing DT.The C34, C36, and C38 dienoic omega-lactones were isolated from sebum of the horse (Equus caballus) and the double bond positions were determined by stepwise chemical dissection and analysis of the fragments. The structures found could be formed by delta 9-desaturation at the C18-stage of fatty acid biosynthesis followed by a second delta 9-desaturation when the chains reached C24, C26, C28, C30, or C32 and then addition of one to seven 2-carbon units. These findings provide insight into the dimensions and organization of the endoplasmic reticulum in cells of the sebaceous glands.
Bush JM, Powers BE.In horses, giant-cell tumors of soft parts are rare neoplasms, with the majority of reported cases occurring within the hind limb muscles and soft tissues in older horses. The following article documents 21 cases of equine giant-cell tumors of soft parts clinically examined within the state of Colorado from 2000 to 2007. The majority of cases occurred in male horses aged 10 years or older. Nine (43%) arose within the hind limbs. Key histologic features included numerous multinucleated giant cells and hemosiderin-laden macrophages admixed with a spindle-cell proliferation. The majority demonstr...
Ma J, Zhang Z, Yao Q, Su C, Yin X, Wang X.Rev, an important accessory protein of equine infectious anaemia virus (EIAV), induces the nuclear export of incompletely spliced viral mRNAs. Rev is translated from the tat-rev mRNA through leaky scanning of the tat CUG. In this study, the function of the Kozak sequence at the beginning of the rev ORF was investigated. Deletion or attenuation of the Kozak sequence resulted in expression of an N-terminal 11 aa-truncated Rev in addition to WT Rev. Truncated Rev displayed weaker promotion of Gag expression and processing than WT Rev. Furthermore, EIAV rescued from an infectious molecular clon...
Hansson E, Skiöldebrand E.To treat osteoarthritic chondrocytes and thereby reduce the inflammation with a drug combination that primarily affects 5-HT- and ATP-evoked Ca2+ signaling. In osteoarthritic chondrocytes, Ca2+ signaling is elevated, resulting in increased production of ATP and inflammatory mediators. The expression of TLR4 and Na+/K+-ATPase was used to evaluate the inflammatory status of the cells. Methods: Equine chondrocytes were collected from joints with mild structural osteoarthritic changes and cultured in monolayers. The cells were treated with a combination of bupivacaine (1 pM) and sildenafil (1 ...
Álvarez C, González N, Luño V, Gil L.The aim of this study was to evaluate the effect of trehalose and lactose extenders on ejaculated and epididymal stallion sperm vitrification. Ejaculated semen samples were collected from seven fertile stallions, and cauda epididymis samples were collected from ten stallion carcasses after slaughter. Both the ejaculated and the epididymis samples were diluted and vitrified using INRA 96® and bovine serum albumin as well as trehalose or lactose. As a control, ejaculated and epididymal samples were collected and frozen using the conventional method. Vitrification was performed by immersing sper...
Black JB, Frampton AR.Equine herpesvirus type 1 (EHV-1) is a highly transmissible pathogen that leads to a variety of clinical disease outcomes in infected horses. A major sequela that can occur after an EHV-1 infection is a neurological disease termed equine herpesvirus myeloencephalopathy (EHM). Clinical manifestations of EHM include fever, ataxia, incontinence, and partial to full paralysis, which may ultimately lead to the euthanization of the infected horse. To develop an effective treatment strategy for EHM, it is critical that the specific virus-host interactions that lead to EHM be investigated so that safe...
Katayama Y, Oikawa M, Kaneko M, Yoshihara T, Yoshikawa H, Yoshikawa T.Three monoclonal antibodies capable of individually recognizing chondrocytes, osteoblasts and osteocytes were prepared. EB-1 reacted with a 55-kDa antigen on the chondrocyte membrane, EB-2 with a 110-kDa antigen on the membrane of osteoblasts and/or partial osteocytes, and EB-3 with a 130-kDa antigen on the membrane of osteocytes. These monoclonal antibodies may be useful probes for studying the differentiation and maturation of osteogenic cells.
Asmis R, Jörg A.Horse eosinophils preincubated with 3H-labelled acetate and stimulated with the Ca2+ ionophores ionomycin or A23187 form a radioactive compound, which we have shown to be 1-O-alkyl-2-[3H]acetyl-sn-glycero-3-phosphocholine (platelet-activating factor). We could detect no 1-O-acyl-2-[3H]acetyl-glycero-3-phosphocholine in the radioactive fraction. The formation of platelet-activating factor was strongly correlated to the generation of leukotriene C4, the main arachidonate metabolite in horse eosinophils, suggesting that platelet-activating factor and leukotriene C4 have a common precursor pool (1...
Warme PK, Scheraga HA.The reported X-ray structure of horse-heart ferricytochrome c has been refined by conformational energy calculations, using a three-stage computational procedure. In stage I, the atomic positions are adjusted to conform to idealized bond lengths and bond angles characteristic of small amino acid derivatives, while yet remaining as close as possible to the X-ray coordinates. In stage II, atomic overlaps are eliminated by adjusting the backbone and side-chain dihedral angles to minimize the nonbonded energy, hydrogen-bonded energy, and rotational energy contributions. In the final stage of refin...
Gurusinghe S, Hilbert B, Trope G, Wang L, Bandara N, Strappe P.Immortalization of chondrocytes enables long term in vitro culture; however, the chondrogenic capacity of transformed cells varies, thus highlighting the need to develop a proliferative and tuneable chondrocyte cell line where hypertrophic differentiation can be controlled. In this study the SV40 large T antigen and human telomerase reverse transcriptase were employed to immortalize pooled equine chondrocytes through lentiviral vector mediated transduction either singly or on combination. Transformed chondrocytes proliferated stably over multiple passages, but resulted in significantly lower e...
García-Rubio I, Fittipaldi M, Trandafir F, Van Doorslaer S.In this work, we show the extreme power of multifrequency HYSCORE (hyperfine sublevel correlation spectroscopy) techniques to unravel the hyperfine interactions of the electron spin with the remote nuclei in the heme site of high-spin ferric heme proteins. Horse heart aquo-metmyoglobin was used as a model system to demonstrate the power of these techniques. Experimental evidence was collected and assigned to protons of the proximal histidine ligand, to the mesoprotons of the heme ligand, and to two different protons of the distal water ligand. The latter difference relates to the stabilization...
Allen GP, Cohen JC, Randall CC, O'Callaghan DJ.The replication of equine herpesvirus type 1 (EHV-1) and type 3 (EHV-3) was unimpeded in three different cell types-equine epithelial cells, equine fibroblasts, and mouse fibroblasts-which had been blocked in their capacity to synthesize host DNA by 2.5 mM hydroxyurea (HU) or 2 mM thymidine (TdR). The rate of DNA synthesis in uninfected or equine herpesvirus-infected cells in the presence of HU or TdR was measured by pulse-labeling cell samples with a labeled DNA precursor at different times after infection. DNA synthesis in uninfected cultures was completely inhibited by both compounds. Howev...
Müller T, Chavaillaz PA, Jörg A, Grob M, Peterhans E.It was shown in several cell types that the dual lipoxygenase and cyclooxygenase inhibitor eicosatetraynoic acid but not the cyclooxygenase inhibitor acetylsalicylic acid suppressed luminol-dependent chemiluminescence. Since lipoxygenase is known to generate chemiluminescence in vitro, these observations were interpreted as evidence for a direct contribution of the lipoxygenase pathway to light emission in intact cells. We have investigated a possible contribution of the lipoxygenase to the chemiluminescence of horse eosinophils by directly comparing the formation of the byproduct chemilumines...
Wang Z, Takezawa Y, Aoyagi H, Abe S, Hikage T, Watanabe Y, Kitagawa S, Ueno T.Apo-ferritin (apo-Fr) mutants are used as scaffolds to accommodate palladium (allyl) complexes. Various coordination arrangements of the Pd complexes are achieved by adjusting the positions of cysteine and histidine residues on the interior surface of the apo-Fr cage.
Lorenzo PL, Liu IK, Illera JC, Picazo RA, Carneiro GF, Illera MJ, Conley AJ, Enders AC, Illera M.Epidermal growth factor (EGF) has been reported to promote different functions in mammalian ovaries, including oocyte maturation. The aim of the present study was to establish: that EGF influences oocyte maturation in ovine and equine, that a tyrosine kinase-dependent intracellular mechanism mediates EGF effect and, that EGF-R receptor is detectable in ovarian follicles by immunohistochemistry methods. Selected ovine and equine oocytes were aspirated from 2-5 mm (ovine) or 25 mm (equine) follicles and cultured in TCM 199 for 22 (ovine) or 36 hours (equine). They are then subjected to culture w...
Wang Z, Yu M, Robinson NE, Broadstone RV, LeBlanc PH, Derksen FJ.The modulatory role of prostaglandin E2 (PGE2) was examined in pony tracheal smooth muscle strips. Although exogenous PGE2 inhibited the contractile response to both electrical field stimulation (EFS) and acetylcholine (ACh) in a dose-dependent manner, the concentration required to inhibit the response to EFS (10 nM) was less than that required to inhibit the response to ACh (0.1 microM). Cyclooxygenase inhibition with aspirin or meclofenamate had no effect on either the response to EFS or to ACh even though PGE2 production was inhibited. Our results demonstrate that in ponies as in other spec...
Zhang CH, Donaldson WL, Antczak DF.A surface antigen of equine B lymphocytes was identified using the Equine Leucocyte Antigen Workshop antibody WS 65. This marker was expressed on almost all equine B cells, but not on T cells, granulocytes or thymocytes. WS 65 strongly stained cells in the follicular areas of lymph nodes and cells in the splenic nodules when tested on frozen tissue sections by immunohistochemistry. Equine leukemic T cells were not labeled by WS 65, and neither were the cells from a horse with B cell leukemia, although these latter cells carried surface immunoglobulin. Immunoprecipitation of lymphocyte membrane...
Poole AW, Heath MF, Evans RJ.Pre-incubation of equine platelets in platelet-rich plasma with adenosine 5'-diphosphate (ADP) induced a reduction in aggregation responsiveness to subsequent additions of ADP. The desensitisation was shown to be homologous since the responsiveness to platelet-activating factor, thrombin, collagen, 5-hydroxytryptamine or ionomycin remained unchanged. Adenosine 5'-(beta-thio)-diphosphate (ADP beta S), a non-hydrolysable analogue of ADP, was shown to act as an agonist inducing aggregation by interaction with the ADP receptor. ADP beta S was then used in the desensitisation studies in which resid...
Guthrie AJ, Short CR, Swan GE, Mülders MS, Killeen VM, Nurton JP.This paper describes the use of subcutaneously-placed tissue chambers as a sterile soft-tissue inflammation model in Thoroughbred horses. Acute, non-immune inflammation was initiated by injecting a sterile lambda carrageenan solution into a tissue chamber. This model was used to study the temporal changes in oxygen and carbon dioxide tensions, pH, bicarbonate, protein, albumin, prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) concentrations, cell counts and differential counts in tissue fluid from inflamed tissue chambers and control chambers. Skin temperatures over control and inflamed chamb...
Campos-Junior PH, Costa GM, de Avelar GF, Segatelli TM, Lacerda SM, Aponte PM, de França LR.Morphometry is a classical quantitative method often used in biology to provide a data basis for functional interpretations/interactions of a particular organ or system. Herein we took advantage of this valuable approach to evaluate the spermatogonial stem cell niche using the horse testis and immunocytochemical localization of GFRA1 [glial cell line-derived neurotrophic factor receptor produced by Sertoli cells)] as an example. Using the NIH ImageJ free software, we describe in detail all the necessary steps to investigate this specific and crucial microenvironment. Based on several recently ...
Leach D, Oliphant L.Incidental to studies of keratinization of the equine hoof wall, annular gap junctions were found in the stratum spinosum of the intertubular horn of the stratum medium. Adjacent cells of the stratum spinosum showed extensive gap junctions, and often local invaginations of one cell into another were bound by gap junctions. It is proposed that these invaginations become detached from the cell surface to form the annular gap junctions. Formation of annular gap junctions may be a means of disposing of plasma membrane in response to changes in cell volume or shape occurring in keratinization. Inte...
Hurwitz A, Finci-Yeheskel Z, Dushnik M, Milwidsky A, Shimonovitz S, Yagel S, Adashi EY, Mayer M.This study examines the effects of interleukin-1 (IL-1) on plasminogen activator (PA) activity and prostaglandin (PG) E production in pregnant mare serum gonadotropin (PMSG)-primed granulosa cells and the potential involvement of PGE in the regulation of ovarian plasminogen activation. Methods: Granulosa cells were obtained from PMSG-primed rat (27-day-old) ovaries and cultured in serum-free conditions for 48 hours in the absence or presence of IL-1 beta (10 ng/mL) with and without transforming growth factor-beta 1 (10 ng/mL). Cellular PA activity was measured through the conversion of plasmin...
McCandless EE, Rai SK, Mwangi D, Sly L, Franz LC.Hydrocortisone is widely accepted as an anti-inflammatory agent and there are many products available containing hydrocortisone as an active ingredient. Surprisingly, there is little data available specifically on the immunological effects of hydrocortisone in large animals. Glucocorticoids are well-characterized for their ability to repress inflammation via a wide variety of mechanisms including suppression of cytokine production. In this study the effects of hydrocortisone on IFN-γ production by equine, bovine, and ovine PBMCs were assessed using flow cytometric or ELISpot analysis. Hydroco...
