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.
Dennis VA, Klei TR, Chapman MR.Supernatants generated by stimulation of peripheral blood mononuclear cells (PBMC) from Strongylus vulgaris sensitized or immunized ponies were assayed in vitro for eosinophil chemotactic activity (ECA) using the filter system in blind well chambers. The supernatants from these cultures were chemotactic for eosinophils, but not for neutrophils. Supernates from cultures of unsensitized PBMC stimulated with S. vulgaris antigen were not chemotactic for eosinophils. ECA was first detected in culture supernatants after 1.5 h of incubation and was dependent on both antigen and PBMC concentrations, b...
Ho JX, Holowachuk EW, Norton EJ, Twigg PD, Carter DC.The amino-acid sequence and three-dimensional structure of equine serum albumin have been determined. The amino-acid sequence was deduced from cDNA isolated from equine liver. Comparisons of the primary structure of equine serum albumin with human serum albumin and bovine serum albumin reveal 76.1% and 73.9% sequence identity, respectively. The three-dimensional structure was determined crystallographically by the molecular-replacement method using molecular coordinates from the previously determined structure of human serum albumin, to a resolution of 0.27 nm. In accordance with the primary s...
Scudamore CL, Pemberton A, Watson ED, Miller HR.Studies have demonstrated that as a result of proteolytic inactivation or complex formation (with neutrophil elastase), human alpha-1-proteinase inhibitor (API) becomes a potent chemoattractant for human neutrophils. The present study aimed to investigate the in vitro chemotactic response of equine neutrophils to an equivalent complex of equine API and neutrophil elastase. No evidence of neutrophil migration was observed towards purified complex derived from equine neutrophil elastase and the Spi 1 isoform of equine API, or to crude mixtures of porcine pancreatic elastase and unseparated equin...
Caron JP, Toppin DS, Block JA.Middle carpal cartilage explants from 4 horses with mild osteoarthritis involving that joint were maintained in tissue culture to test the effects of a polysulfated glycosaminoglycan (PSGAG) on proteoglycan synthesis and degradation. Cultures were exposed to 0.025 or 25 mg of PSGAG/ml for 48 hours, after which the medium was replaced with medium containing similar doses of PSGAG and 35S. Subsequently, the sulfated proteoglycan content of the medium and extracts of the explants was measured. Gel filtration chromatography was used to estimate the size and to purify the principal, large proteogly...
Ball BA, Brinsko SP, Thomas PG, Miller PG, Ellington JE.Development of 1- to 2-cell in vivo fertilized equine embryos cultured with or without uterine tubal epithelial cells (UTEC) was studied. One- to 2-cell embryos (n = 26) were collected surgically from the uterine tubes of pony mares 1 day after ovulation. Four- to 8-cell embryos (n = 9) were collected 2 days after ovulation. Presumptive zygotes and 2-cell embryos were cultured with (n = 17) or without (n = 9) UTEC, and all 4- to 8-cell embryos were cocultured with UTEC as positive controls. Uterine tubal epithelial cells were used as cell suspensions within 2 weeks after initiation of cultures...
Kordula T, Dubin A, Schooltink H, Koj A, Heinrich PC, Rose-John S.Horse blood leucocytes contain an elastase inhibitor (HLEI) belonging to the serpin family. Poly(A)+RNA isolated from these cells was used to construct a cDNA library in lambda gt10, which was first screened with a synthetic degenerate oligonucleotide probe corresponding to the amino acid sequence of the reactive centre of the inhibitor. Three clones were obtained covering the entire coding region of the protein. Sequencing of these clones showed identity with the amino acid sequence obtained from Edman degradation of the elastase inhibitor. The coding sequence of the HLEI cDNA was cloned into...
Räsänen LA, Karvonen U, Pösö AR.In situ hybridization was used to localize xanthine dehydrogenase (XDH) mRNA in horse skeletal muscle. Capillary endothelial cells were found to express XDH, but muscle cells did not give any signal. The digoxigenin-labelled probe was produced by PCR with primers based on the cDNA sequence of mouse XDH and horse lung cDNAs. A 4.3 kb mRNA was detected in a Northern blot.
Evans MJ, Kitson NE, Livesey JH, Donald RA.Perifused equine anterior pituitary cells were used to investigate the effect of cortisol on the ACTH response to pulses of corticotrophin-releasing hormone (CRH; 0.01 nmol/l) and arginine vasopressin (AVP; 100 nmol/l), given for 5 min every 30 min for 690 min and ACTH measured in 5-min fractions. At the fourth pulse of secretagogue (0 min), a constant perifusion with cortisol began (0 nmol/l (control), 100, 200, 500, 5000 and 50,000 nmol/l) and continued until the ninth pulse (150 min). For each pulse of secretagogue, the amount of ACTH (pmol) secreted in response to each pulse (ACTH response...
Coyne CP, Fenwick BW, Iandola J, Williams D, Griffith G.Objectives of this investigation were to extract and isolate protein fractions inhibitory to the cytotoxic properties of tumor necrosis factor-alpha (TNF-alpha). In this context, mixed populations of WBC were harvested from equine blood and were stimulated with a combination of a synthetic chemotactic peptide and a calcium ionophore. Several methods were subsequently applied for the initial preparation of cell-free crude protein extracts, including fractional precipitation with gradient concentrations of ammonium sulfate and preparative-scale isoelectric focusing. In addition, protein fraction...
Fukunaga K, Ninomiya M, Oohara Y, Kusunose K, Okamura Y, Nagasaki H, Ishino S, Kadota K.Lymphoplasmacytic lymphoma found in a 6-year-old Anglo-Arabian stallion was investigated histologically, immunohistochemically and ultrastructurally. The animal showed a large mediastinal mass and generalized lymph node involvement. The neoplastic cells were in various differentiation stages of small lymphocyte, centrocyte, centroblast, immunoblast and plasma cell. Some neoplastic cells showed positive cytoplasmic reactivity for mu and lambda chains. There were well developed rough endoplasmic reticulum (RER) and Golgi complexes in plasmacytoid cells, and slightly developed RER or a few long s...
Joujou-Sisic K, Granérus M, Wetterling H, Wikström K, Engström W, Jeffcott L, Schofield PN, Welin A.The expression of the insulin like growth factor (IGF) II gene has been examined in the developing equine fetus. It was found that IGF II transcripts were present in abundant quantities in third trimester embryonic and extraembryonic tissues as for example the placenta. The expression of the IGF II gene was high in the fetal liver where two prominent transcripts--4.6 and 4.1--kB were produced. However, these transcripts could not be traced in the adult liver. Instead we found two different transcripts with the sizes of 4.0 and 2.9 kB in the adult liver. These findings taken together with the d...
Evans MJ, Marshall AG, Kitson NE, Summers K, Donald RA.The multifactorial control of ACTH is well established. We wished to establish and characterize an in-vitro perifusion system, using equine anterior pituitary cells and physiological concentrations of secretagogues, to investigate factors which affect the dynamics of ACTH secretion. Anterior pituitary tissue was divided for dispersion into cells with collagenase, trypsin or dispase, or by mechanical dispersion. After dispersal followed by 18-h incubation, cells were perifused and the ACTH response to 10-min pulses of arginine vasopressin (AVP; 100 nmol/l), corticotrophin-releasing hormone (CRH...
Tremblay GM, Ferland C, Lapointe JM, Vrins A, Lavoie JP, Cormier Y.Bronchoalveolar lavages (BAL) were performed before and after 3 weeks of housing in 5 horses suffering from COPD and 5 normal horses. In the two groups, the total number of cells recovered remained unchanged after stabling. The most common cell populations in BAL fluid of control animals were alveolar macrophages (46.4%) and lymphocytes (44.9%). The percentage of neutrophils increased after stabling from 8.7% to 27.6%. In COPD horses, lymphocytes predominated (40.7%) in animals at pasture with neutrophils increasing from 29.4% to 71.6% after stabling. After fractionation by Percoll density gra...
Ellington JE, Ball BA, Yang X.The objective of this study was to determine whether coculture of stallion spermatozoa and mare oviductal (uterine tubal) epithelial cells induced sperm cell capacitation in vitro. Capacitation as determined by zona binding and chlortetracycline staining of the sperm cells was compared for stallion spermatozoa: (1) incubated with medium alone (negative control), (2) treated with calcium ionophore A23187 (positive control) or (3) cultured with mare oviductal epithelial cells (OEC) for 4 h. Chlortetracycline staining patterns of sperm cells bound to the zonae were used to group spermatozoa as un...
Prieto D, Hernandez M, Rivera L, Ordaz E, Garcia-Sacristan A.The aim of the present study was to determine the distribution and density of catecholaminergic nerve fibres and cells in the equine ureter by using immunohistochemical techniques to localise the enzyme tyrosine-hydroxylase (TH). TH-immunoreactive (TH-IR) nerve fibres entered the wall of the ureter as adventitial nerve trunks accompanying the blood vessels. These trunks repeatedly branched as they coursed through the muscular layer towards the epithelium, forming muscular, perivascular and subepithelial nerve plexuses. TH-IR nerve fibres were especially numerous in the pelvic and intravesical ...
Scepek S, Lindau M.We have investigated the granule fusion events during exocytosis in horse eosinophils by time-resolved patch-clamp capacitance measurements. Stimulation with intracellular GTP gamma S leads to a stepwise capacitance increase by 4.0 +/- 0.9 pF. At GTP gamma S concentrations < 20 microM the step size distribution is in agreement with the granule size distribution in resting cells. Above 80 microM the number of steps is reduced and very large steps occur. The total capacitance increase, however, is unaffected. These results show that at high GTP gamma S concentrations granule--granule fusion o...
Threadgill DS, Steagall WK, Flaherty MT, Fuller FJ, Perry ST, Rushlow KE, Le Grice SF, Payne SL.The putative dUTPase domain was deleted from the polymerase (pol) gene of equine infectious anemia virus (EIAV) to produce a recombinant delta DUpol Escherichia coli expression cassette and a delta DU proviral clone. Expression of the recombinant delta DUpol polyprotein yielded a properly processed and enzymatically active reverse transcriptase, as determined by immunoblot analysis and DNA polymerase activity gels. Transfection of delta DU provirus into feline (FEA) cells resulted in production of virus that replicated to wild-type levels in both FEA cells and fetal equine kidney cells. In con...
Sisken BF, Zwick M, Hyde JF, Cottrill CM.This review covers the development and maturation of the cerebellum of the horse and compares this developmental sequence with that of man, mouse and chicken. These comparisons attempt to correlate morphological and neurochemical features, developmental time and functional performance necessary for survival at birth. Although there is great disparity between these 3 species, the basic anatomical structures of the cerebellum are present as are specific cellular groups, synapses and neurochemical markers. In addition to this structural homogeneity, other attributes of the cerebellum are its easi...
Sasaki K, Igarashi S, Amasaki T, Amasaki H, Nishita T, Kano Y, Asari M.Immunohistochemical localizations of carbonic anhydrase isozymes (CA-I, CA-II and CA-III) in equine and bovine digestive tracts were studied. In the horse, epithelial cells in both the oesophagus and non-glandular part of the stomach lacked all three isozymes. In contrast, surface epithelial and parietal cells in the glandular region of the stomach showed reactivity for CA-II. In the small intestine, absorptive columnar cells covering the villi in the duodenum were positive for CA-II. The epithelium of the jejunum and ileum lacked all three isozymes. In the large intestine, CA-II was detected ...
Inaba M, Goto I, Sato K, Maede Y.This report describes a unique response of the anion transporter in equine erythrocytes to the fluorescent substrate N-(2-aminoethyl sulfonate)-7-nitrobenz-2-oxa-3-diazole (NBD-taurine). Equine erythrocytes showed fluxes of NBD-taurine both inward and outward at rates considerably slower than those in human cells. These fluxes were completely abolished by a typical anion transport inhibitor, 4,4'-diisothiocyanostilbene-2,2'-disulfonate. Furthermore, NBD-taurine competitively inhibited the uptake of phosphate in equine red cells with an inhibition constant of phosphate that was slightly higher ...
Carvalho M, Derse D.Equine infectious anemia virus (EIAV) is a lentivirus that causes a chronic disease of horses characterized by cyclic episodes of fever, anemia, and viremia. Although the genome and promoter of EIAV are much less complex than those of its relatives the primate immunodeficiency viruses, the cellular proteins that activate and regulate transcription of EIAV have not yet been identified. In this report, we show by electrophoretic mobility shift assays and DNase I footprinting that the EIAV promoter contains multiple binding sites for ubiquitous, cell type-specific, and inducible cellular proteins...
Wilson DV, Stick JA.The role of platelet-activating factor in mediating the cardiovascular and peripheral cellular responses to large-colon ischemia and reperfusion, was explored in anesthetized ponies. A specific platelet-activating factor (PAF) antagonist (WEB 2086) was administered to a group of 6 ponies, and another 6 ponies (controls) were given an equivalent volume of saline solution, prior to 1 hour of large-colon torsion. After correction of the torsion, ponies were monitored during the reperfusion period. Significant (P < 0.05) hypotension and metabolic acidosis developed in all ponies after correctio...
Richardson DW, Clark CC.Hexosamine concentration (an index of proteoglycan content), DNA content (an index of cellularity), and [35S]sulfate incorporation (an index of proteoglycan synthesis) of articular cartilage were measured in biopsy specimens from medial proximal sesamoid bone, medial condyle of the third metacarpal bone, and proximal dorsal rim of the proximal phalanx in both metacarpophalangeal joints of 6 adult horses. One limb was then placed in a fiberglass cast that extended down from the proximal portion of the metacarpus and enclosed the hoof; the other limb was not casted. After 30 days of stall confin...
Gargiulo AM, Pedini V, Ceccarelli P.The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha-...
Massanyi L, Janisch R.According to the distribution of IMP, three different regions can be recognized on PF of the post-acrosomal plasma membrane of bull, ram, and boar spermatozoa. They are: (1) a region with linear aggregation of IMP, (2) a region with fewer and scattered IMP, and (3) a region with more numerous IMP. In the last two regions IMPs are randomly distributed or a clustering of certain particles is visible. In stallion spermatozoa the last two areas are undistinguishable. There are evident interspecies differences in the arrangement of linear aggregations of IMP which are characteristic for each specie...
Patnaik AK.In a retrospective study, granular cell tumors in six dogs (Nos. 1-6), three cats (Nos. 1-3), one horse (No. 1), and one cockatiel (Nymphicus hollandicus) (No. 1) and a meningioma with a granular cell component in one dog (No. 7) were examined histologically and immunohistochemically. These tumors were identified by histologic examination of surgical biopsy specimens, except in the horse, in which the tumor was an incidental finding at necropsy. These diagnoses were initially made by more than one pathologist. Five of the six granular cell tumors in the dogs were in the oral cavity; one of the...
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...
Bragulla H.The pre- and perinatal development of the hoof cartilage is described concerning the histological structure and surrounding vessels. Beginning in the third month of fetal development, the anlage of the hoof cartilage is still present in typical shape and location. It is built out of mesenchymal connective tissue. During further fetal development, the connective tissue cells will differentiate into two cell populations, fibroblasts and chondroblasts. Vessels, traversing the hoof cartilage, are surrounded by loose connective tissue, which will partially develop fibrocartilage. At birth, hoof car...
von Rotz A, Friess AE.Sinus hairs, which are tactile organs of most mammals, are differentiated into cavernous and sinus types. The horse has the cavernous type. Horse lower lips were perfused in diluted Karnovsky's fixative and sinus hair processed for scanning electron microscopy. Anastomosing trabeculae of different thickness and shape originate from the internal connective tissue layer and extend to the external layer, thus forming a dense meshwork suspending the hair root like a net. However, many of the distal trabeculae do not reach the external wall of the blood sinus but end in a finger-like knob within th...
Podstawski P, Witarski W, Szmatoła T, Bugno-Poniewierska M, Ropka-Molik K.Sarcoids are the most common skin neoplasm in the Equidae family. Sarcoids are benign, but may cause severe damage in affected animals. Due to the high risk of post-treatment recurrence and the lack of an effective method of treatment, it is reasonable to perform studies on the molecular aspects of this neoplasm. Therefore, the present studies analyzed five genes (cell cycle control binding protein alpha, coronin 1b, metalloproteinase 2, tissue inhibitor of metalloproteinases 3 and vimentin) related to cell mobility and invasion traits. Primary healthy fibroblasts and sarcoid cells were obtain...
Nieto JE, Aldridge BM, Beldomenico PM, Aleman M, Snyder JR.To determine the nucleotide sequence of the equine intestinal fatty acid binding protein (I-FABP) gene, its expression in various regions of the gastrointestinal tract, and the use of measuring I-FABP in horses with colic. Animals-86 horses with colic. Methods: The mRNA sequence for the I-FABP gene was obtained by use of a rapid amplification of complementary DNA ends technique. Comparative I-FABP gene expression was quantitated by use of a real-time reverse transcription-polymerase chain reaction assay. Amounts of I-FABP in abdominal fluid and plasma were measured by use of an ELISA kit. Asso...
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...
Dawson J, Lees P, Sedgwick AD.Equine polymorphonuclear (PMN) and mononuclear (MN) leucocytes were separated on Percoll gradients and used to study the chemoattractant properties of the polar ether-linked phospholipid, platelet activating factor (PAF). Six concentrations of PAF ranging from 1 ng/ml to 100 micrograms/ml were studied in each of two in vitro assay systems, the agarose microdroplet and a microfilter technique. Very significant (p less than 0.01) increases in the movement of both PMN and MN cells were obtained with most concentrations of PAF. In two instances there was no apparent concentration-response relation...
Evans MJ, Mulligan RS, Livesey JH, Donald RA.Perifused equine anterior pituitary cells were used to investigate the relationships between the secretion of ACTH and substances known to either stimulate (corticotrophin-releasing hormone (CRH), and arginine vasopressin (AVP)) or inhibit (cortisol) ACTH secretion. The experiments were designed to mimic the hormone milieu present in vivo in the horse, with cortisol (0 or 100 nmol/l) and CRH (0 or 0.02 nmol/l) perifused continuously, and pulses of AVP (10 nmol/l) applied for 5 min at 30-min intervals. In columns perifused with 0.02 nmol CRH/l there was no significant overall effect of 100 nmol...
Tura G, Brunetti B, Brigandì E, Rinnovati R, Sarli G, Avallone G, Muscatello LV, La Ragione RM, Durham AE, Bacci B.Sarcoids are among the most common tumors diagnosed in equids; their association with bovine papillomaviruses (BPV) infection has been widely reported, but the mechanism of carcinogenesis has not been fully elucidated. To verify whether BPV infection causes dysregulation of the pRb-Cyclin D1-p16-p53 pathway as reported for human papillomavirus (HPV), the study employed immunohistochemistry to test 55 equine sarcoid biopsies for the expression of pRb, Cyclin D1, and p53 cell cycle regulatory proteins and to evaluate the proliferative rate through Ki67. High Cyclin D1 and pRb expression were obs...
Maeda Y, Ohtsuka H, Tomioka M, Tanabe T, Nambo Y, Uematsu H, Oikawa MA.Escherichia coli(E. coli) isolated from the uterus of a Thoroughbred mare with bacterial endometritis was used to evaluate the effect of progesterone (P(4)) on the immune response of mares. Peripheral blood mononuclear cells (PBMCs) were collected from 10 nonpregnant clinically healthy adult mares (range, 4-12 years) during diestrus, four Thoroughbreds and six Hokkaido native horses. Cell proliferation and expression of cytokine mRNA, including interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-10, of PBMCs stimulated with E. coli and P(4) were examined in vitro. P(4) was...
Johnson L, Amann RP, Pickett BW.Changes within the equine seminiferous tubules during the cycle of the seminiferous epithelium were studied light and scanning electron microscopy (SEM). Once observed with SEM, tubules were sectioned and staged using light microscopy. As viewed by SEM, the weblike, spongy cytoplasm of germ cells or Sertoli cells in stages I and II extended over the entire height of the germinal epithelium. The cytoplasm of the basal portion of the germinal epithelium in stages III to VIII was similar to that in stages I and II. However, the cytoplasm which occupied the luminal third of the epithelium in stage...
Martin EM, Duck FA, Winlove CP.We have previously shown that MHz frequency ultrasound causes contraction of the carotid artery in vitro. We now extend this investigation to equine mesenteric arteries and investigate the cellular mechanisms. In vitro exposure of the large lateral cecal mesenteric artery to 4-min periods of 3.2 MHz continuous wave ultrasound at acoustic powers up to 145 mW induced reversible repeatable contraction. The magnitude of the response was linearly dependent on acoustic power and, at 145 mW, the mean increase in wall stress was 0.020 ± 0.017 mN/mm(2) (n = 34). These results are consistent with our p...
Bulak K, Łopuszyński W, Lutnicki K, Pomorska-Zniszczyńska A, Śmiech A, Jodłowska-Jędrych B.Granular cell tumor (GCT) is a soft tissue neoplasm characterized by abundant intracellular eosinophilic granules. The majority of GCTs are benign, although some display malignant behavior. Furthermore, GCTs may mimic other neoplasms. The clinical course and biology of GCTs are poorly understood. Regarding the histogenesis of GCT, a Schwann cell origin is currently favored in light of immunohistochemical and ultrastructural analyses. However, based on literature data, some of the primitive GCTs show non-neural origin; therefore, the histogenesis of this tumor has remained enigmatic. Granular c...
Hudson NP, Mayhew IG, Pearson GT.Intracellular microelectrode recordings were made from smooth muscle cells in cross-sectional preparations of equine ileum, superfused in vitro. Membrane potential oscillations and spike potentials were recorded in all preparations, but recordings were made more readily from cells in the longitudinal muscle layer than from cells in the circular layer. The mean (se) resting membrane potential (RMP) of smooth muscle cells in the longitudinal muscle layer was -51.9 (1.2) mV, and the membrane potential oscillations in this layer had a mean amplitude of 4.8 (0.4) mV, a frequency of 9.0 (0.1) cycles...
Kato H, Seidel GE, Squires EL, Wilson JM.In vitro matured horse oocytes with a first polar body (n = 68) were each injected with a single spermatozoon and divided into 2 groups: Group 1 oocytes were treated with 10 microM calcium ionophore A23187 for 5 min while Group 2 oocytes received no activation treatment. After culture in vitro for 2 days, significantly more oocytes treated with A23187 (5/24, 21%) cleaved than oocytes without activation treatment (2/44, 5%, P<0.05). All 7 cleaved zygotes from both treatment groups were transferred to recipient mares but no pregnancies resulted.
Mair TS, Stokes CR, Bourne FJ.Mast cells in the equine respiratory mucosa were studied at both light--and transmission electron--microscope levels. Mast cells were identified at all levels of the tract, with the greatest cell density in the nasopharynx. The majority (57 to 94 per cent) of this cell population were located within the connective tissue of the lamina propria. Up to 20 per cent of these cells were associated with the mucosal glandular tissue, whilst small numbers were present within the surface epithelium and in association with nodular lymphoid tissue. In the peripheral lung tissue 20 per cent of the mast cel...
Peters GJ, Oosterhof A, Veerkamp JH.1. Adenosine inhibits thymidine and uridine incorporation of PHA-stimulated lymphocytes of man and horse at concentrations higher than 50 and 10 microM, respectively. Deoxyadenosine is inhibitory at concentrations higher than 100 microM. Thymidine and uridine incorporation of porcine lymphocytes are elevated 5-7-fold by 25-100 microM adenosine, deoxyadenosine, inosine and hypoxanthine. Leucine incorporation of PHA-stimulated lymphocytes was affected by adenosine and deoxyadenosine in the same way, but to a lower extent. 2. Effects of adenosine and deoxyadenosine were more pronounced at shorter...
González-Fernández L, Macedo S, Lopes JS, Rocha A, Macías-García B.Equine in vitro fertilization (IVF) is still inconsistent. In the present work, we studied how modified Whitten's (MW) medium and Tissue Culture Medium 199 (TCM) added with Foetal Bovine Serum (FBS; 10% v/v) or Bovine Serum Albumin (BSA; 7 mg/ml) affected equine gametes to subsequently run IVF trials. Compact (Cp) and expanded (Ex) cumuli equine oocytes were matured and placed in TCM or MW supplemented with BSA or FBS for 18-20 h (no sperm added). In Ex oocytes, TCM-199 added with FBS or BSA resulted in higher metaphase II (MII) rates (75.7% and 62.7%, respectively) than MW added with BSA (54%...
Chopineau M, Martinat N, Marichatou H, Troispoux C, Auge-Gouillou C, Stewart F, Combarnous Y, Guillou F.Horse LH/chorionic gonadotrophin (eLH/CG) exhibits, in addition to its normal LH activity, a high FSH activity in all other species tested. Donkey LH/CG (dkLH/CG) also exhibits FSH activity in other species, but about ten times less than the horse hormone. In order to understand the molecular basis of these dual gonadotrophic activities of eLH/CG and dkLH/CG better, we expressed, in COS-7 cells, hybrids between horse and donkey subunits, between horse or donkey alpha-subunit and human CG beta (hCG beta), and also between the porcine alpha-subunit and horse or donkey LH/CG beta. The resultant r...
Chopineau M, Martinat N, Gibrat JF, Galet C, Lecompte F, Foulon-Gauze F, Pourchet C, Guillou F, Combarnous Y.To identify amino-acids in the alpha-subunit important for expression of heterospecific FSH activity of horse (e) LH/choriogonadotropin (CG) (eLH) and donkey (dk) LH/CG (dkLH) (FSH/LH ratio ten times higher for eLH than for dkLH); this FSH activity absolutely requires an equid (donkey or horse) alpha-subunit combined with an equid beta-LH subunit. Methods: Chimeric alpha-subunits possessing the first 63 amino-acids of the porcine (p) and the last 33 amino-acids of the donkey alpha-subunit (alphap-dk) and the inverse (alphadk-p) were constructed. Porcine-specific amino-acids were introduced by ...
Grosenbaugh DA, Hood DM, Amoss MS, Williams JD.Epidermal growth factor (EGF) receptors were detected in plasma membrane preparations of equine hoof wall laminar tissue at concentrations comparable to that of equine liver. Scatchard analysis of the equilibrium binding data suggested the presence of two classes of EGF binding sites in most of the controls (plasma membranes from clinically normal horses); a high-affinity class and a more numerous low-affinity class. The dissociation constant of the low-affinity class of EGF-specific receptors (KD = 1 x 10(-9)M) is in reasonable agreement with other values established for the EGF receptor. The...
Xijier , Mori Y, Fukuoka M, Cairangzhuoma , Inagaki M, Iwamoto S, Yabe T, Kanamaru Y.Native alpha-lactalbumins (α-LA) from equine, bovine, and human milk were not cytotoxic. However, after treatment with trifluoroethanol (TFE), all three α-LAs exhibited cytotoxicity. Toxic potencies were distinctly different among them. Equine α-LA was the most robust, bovine α-LA was moderate, and human α-LA was weak. There were no significant structural changes as between the native and the TFE-treated α-LAs.
Damasceno Teixeira TV, Fry RC, McKinnon A, Fry KL, Kelly JM, Verma PJ, Burden C, Salamone DF, Gambini A.Epigenetic perturbations during the reprogramming process have been described as the primary cause of the low efficiency of somatic cell nuclear transfer (SCNT). In this study, we tested three strategies targeting nuclear reprogramming to investigate effects on equine SCNT. First, we evaluated the effect of treating somatic cells with chetomin, a fungal secondary metabolite reported to inhibit the trimethylation on histone 3 lysine 9 (H3K9 me3). Second, caffeine was added to the culture medium during the enucleation of oocytes and before activation of reconstructed embryos as a protein phospha...
Pavone S, Mandara MT.The interstitial cells of Cajal (ICC) play a key role in the control of intestinal motility and have been implicated in several human gastrointestinal dysmotility syndromes, in equine grass sickness and in other intestinal disorders where a significant reduction in ICC density was observed. Objective: To investigate the density of ICC in clinically normal horses, ICC c-Kit expression was evaluated by image analysis in order to obtain numerical data. Methods: Intestinal samples from the jejunum to small colon from 5 clinically normal horses were studied. Immunohistochemical labelling of ICC was...
Mizukoshi N, Sakamoto K, Iwata A, Ueda S, Kamada M, Fukusho A.The reverse transcription followed by the polymerase chain reaction (RT-PCR) technique was applied to the detection of African horsesickness virus (AHSV) using primers specific for attenuated AHSV serotype 4 segment 5 (NS1 gene). Total RNA which contains both messenger RNA and genomic dsRNA was extracted by the acid guanidinium-phenol-chloroform method from the AHSV infected Vero cells and was used as templates to optimize the RT-PCR. A pair of primer (NP2-NP32) amplified the product of the expected size from all serotypes of attenuated AHSV when four pairs of primers were tested. Using this p...
Alm H, Hinrichs K.The period of protein synthesis necessary for meiotic maturation in horse oocytes initially having compact or expanded cumulus cells was studied. Oocytes incubated in the presence of cycloheximide after 0, 4, 8, 12 or 16 h maturation in vitro (total incubation time 24 h) were matured for 24 h, or were incubated with cycloheximide for 24 h and then matured for 24 h. Incubation with cycloheximide from 0 h was effective in suppressing maturation (no significant increase in maturing oocytes compared with controls fixed directly after removal from the follicle) in both expanded and compact groups a...
Doyle DG.During an electron and light microscopic study of the equine intestinal epithelium, it was observed that some secretory granules of the undifferentiated crypt epithelium were incorporated into the nucleus during mitosis. A study was made of the chemical nature of the granules, using standard histochemical techniques: PAS-Alcian blue, Deamination-PAS, and Ninhydrin-Schiff reactions. The granules contained a neutral protein-polysaccharide complex with many terminal amino groups, possibly an antibody (IgA). The intranuclear granules underwent coalescence and degeneration during differentiation. T...
Moussa M, Bersinger I, Doligez P, Guignot F, Duchamp G, Vidament M, Mermillod P, Bruyas JF.Vitrification using open pulled straw (OPS) has provided encouraging results with embryos from other species. The aim of this study was to compare the survival of 6.5- and 6.75-day-old equine embryos after OPS vitrification and slow-cooling. Eighteen embryos were frozen using a slow-cooling method. Embryos were placed in modified PBS with increasing glycerol concentration (2.5%, 5%, 7.5% and 10% (v/v) 5 min each). Embryos were loaded into 0.25 ml straws then placed in a programmable freezer and subsequently plunged into liquid nitrogen. After thawing, cryoprotectant was removed by five steps w...
Fitzpatrick JL, Bailey M, Harbour DA, Stokes CR.Adult ponies which were fed ovalbumin (OVA) daily for 2 weeks had significantly greater serum anti-OVA IgG (P = 0.001) and antigen specific lymphocyte responses (P = 0.031) after intramuscular injection with OVA given with saponin than control ponies which had not been fed the antigen. This suggests that, despite the lack of evidence of B- or T-cell activation in peripheral blood during the period of OVA feeding, the animals were primed for an active secondary immune response. Adult ponies were challenged with equine rotavirus, strain H-2, but no statistically significant differences were foun...
Garland A, Wierenga C, McCrae P, Pearson W.The purpose of this study was to determine anti-inflammatory and/or chondroprotective effects of Equine Omega Complete (EOC) on cartilage explants stimulated with lipopolysaccharide (LPS). Explants were aseptically prepared from the intercarpal joints of 17 market-weight pigs and placed in culture at 37°C for a total of 120 hours. For the final 96 hours, explants were conditioned with a simulated digestion extract of EOC (0, 36 or 180 μL/mL), and for the final 48 hours explants were stimulated with LPS (0 or 15µg/mL). Media was removed and replaced every 24 hours. Samples from the final 48 ...
Woodward MC, Andrews FM, Kearney MT, Del Piero F, Hammerberg B, Pucheu-Haston CM.To characterize the response of skin of nonallergic horses following ID injection of polyclonal rabbit anti-canine IgE (anti-IgE) and rabbit IgG. Methods: 6 healthy horses. Methods: Skin in the cervical area was injected ID with anti-IgE and IgG. Wheal measurements and skin biopsy specimens were obtained before and 20 minutes and 6, 24, and 48 hours after injection. Tissue sections were evaluated for inflammatory cells at 4 dermal depths. Immunohistochemical analysis for CD3, CD4, and CD8 was performed, and cell counts were evaluated. Results: Anti-IgE wheals were significantly larger than IgG...
