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.
Wensvoort P, Steenbergen-Botterweg WA.When adipose tissues of horses and ponies affected with generalized steatitis were extracted by acetone, methanol and chloroform, non-extractable lipids were found to be present, which had become insoluble as a result of peroxidation and polymerization and had acquired autofluorescent characteristics. The origin of these lipids varies. Peroxidation occurs in three different lipid compartments, namely in the cytoplasm of the necrotized adipose cells, in the macrophagess and in the fat globules present in stroma.
Carter EI, Valli VE, McSherry BJ.The peripheral blood cells from Standard bred horses were subjected to procedures which will separate equine peripheral blood cells with good precision and efficiency into red cell, leukocyte, and platelet fractions. The separated cells have normal morphology and the differential count of the separated granulocytes and lymphocytes is unchanged from that of the original sample.
England JJ, Watson RE, Larson KA.On electron microscopic examination of a cell line derived from an equine sarcoid, intracytoplasmic oncornavirus-like particles were seen. Cells treated with idoxuridine-dimethyl sulfoxide (idu-dmso) had a two- to four-fold increase in the number of particles as compared with nontreated cells or cells treated with dmso alone. The intracytoplasmic virus-like particles were double membrane structures measuring 80 to 100 nm. in diameter. Particles were seen extracelluarly or budding from the cell membrane into the extracellular space. These extracellular particles were 100 nm. in diameter and con...
Crichton RR.The researchers investigated the biochemical properties of ferritin, a protein responsible for iron storage in the body. They identified its distribution and structure, noting variations in different species and tissues. […]
Milam SB, Mackay RJ, Skelley LA.Secretion of tumor necrosis factor (TNF) by equine mammary exudate macrophages (MEM phi) exposed to bacterial lipopolysaccharide (LPS) was dose-dependent and was maximal (216.5 +/- 51.9 U/ml) at 100 micrograms LPS/ml, the highest concentration tested. All concentrations of dexamethasone tested (10(-8) to 10(-4) M) significantly (P less than or equal to 0.05) inhibited TNF production by MEM phi when the agent was added 1 hour before LPS. Pretreatment with pentoxifylline at concentrations greater than 3 micrograms/ml also significantly (P less than or equal to 0.05) reduced secretion of TNF by M...
Leise BS, Yin C, Pettigrew A, Belknap JK.Further knowledge of equine keratinocyte physiology and keratinocyte response to various stimuli is important in developing a better understanding of disease states involving the epidermis. Objective: To assess the inflammatory cytokine response of cultured equine keratinocytes to various pathogen-associated molecular pattern molecules (PAMPs) from both Gram-negative and positive bacteria likely to be present in equine sepsis. Methods: Keratinocytes were isolated from skin of 2 horses and primary cultures performed. Keratinocytes were harvested for RNA extraction after exposure to lipopolysacc...
Walter I.Uterine tubes from cow, sheep, horse, pig, dog, cat, rabbit, and guinea pig were examined immunohistochemically for presence and distribution of contractile cells in the mucosal lamina propria. We tested for the presence of alpha-smooth muscle actin, tropomyosin, desmin, smooth muscle myosin (heavy chain) and cytoskeletal proteins vimentin and cytokeratin. Immunostaining for alpha-smooth muscle actin showed two distribution patterns: either positive cells were freely dispersed in the mucosal lamina propria or a distinct subepithelial layer of positive cells was seen. The first distribution pat...
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...
Leder L, Bosshard HR.It has long been known that antibodies to cytochrome c can distinguish between closely sequence-related cytochromes c. Because the 3-D-structure of the polypeptide chain is virtually identical among eukaryotic cytochromes c, antibody specificity is directed against amino acid substitutions within a common polypeptide folding pattern. The question arises if the specificity is observed at the level of the 3-D-structure (conformational epitopes) and/or at the level of the primary structure (sequential epitopes). Using rabbit sera to horse cytochrome c, we show that discrimination against the host...
Lemos KR, Marques LC, Deaquino LP, Alessi AC, Machado RZ.An histochemical and immunohistochemical study was carried out to evaluate the mechanisms of immune response of horses experimentally infected by Trypanosoma evansi. For this purpose the HE histochemical stain and the avidin biotin peroxidase method were used. To determine the presence and immunoreactivity of immune cells we used anti-major histocompatibility complex II antibodies. Cellular infiltration phenotype was characterized with the aid of anti-CD3 antibody for T lymphocytes and by anti-BLA 36 antibodies for B lymphocytes. Macrophages were marked with an antibody against myeloid/histyoc...
Haerdi-Landerer MC, Suter MM, Steiner A, Wittenbrink MM, Pickl A, Gander BA.For the treatment of septic arthritis in large animals, the local application of antibiotics as a slow release system may be an appropriate means to reach high local bioactivity and low systemic side effects and drug residues. In this study, doxycycline microspheres were developed and tested in vitro for their drug-release properties, suitability for intra-articular application and antimicrobial activity. Methods: The development of a slow release system was achieved by microencapsulation of the drug into poly(lactide-co-glycolide) microspheres by a novel ultrasonic atomization method. Drug el...
van Dinten LC, den Boon JA, Wassenaar AL, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV) is a positive-strand RNA virus that uses a discontinuous transcription mechanism to generate a nested set of six subgenomic mRNAs from which its structural genes are expressed. A stable bacterial plasmid (pEAV030) containing a full-length cDNA copy of the 12.7-kb EAV genome was constructed. After removal of a single point mutation in the replicase gene, RNA transcripts generated in vitro from pEAV030 were shown to be infectious upon electroporation into BHK-21 cells. A genetic marker mutation was introduced at the cDNA level and recovered from the genome of the pro...
Bertram TA.Differences in neutrophil morphology between various species of domestic animals are evident when morphometric techniques are used. Morphometric analysis can be coupled with functional assays of degranulation to demonstrate changes in granule volume after neutrophil activation (Bertram and Jensen, 1984). Morphometric and functional analysis of the neutrophil can also be used to evaluate the response of neutrophils to infectious agents (Coignoul et al., 1984a). Comparison of these assays between animal species may provide insight into the susceptibility of animals to various microbial pathogens...
Schauer M, Kleinwort KJH, Degroote RL, Wiedemann C, Kremmer E, Hauck SM, Deeg CA.The GTP-binding protein septin 7 is involved in various cellular processes, including cytoskeleton organization, migration and the regulation of cell shape. Septin 7 function in lymphocytes, however, is poorly characterized. Since the intracellular signaling role of septin 7 is dependent on its interaction network, interaction proteomics was applied to attain novel knowledge about septin 7 function in hematopoietic cells. Our previous finding of decreased septin 7 expression in blood-derived lymphocytes in ERU, a spontaneous animal model for autoimmune uveitis in man, extended the role of sept...
Dahm AM, de Bruin A, Linat A, von Tscharner C, Wyder M, Suter MM.We describe the establishment and characterisation of equine keratinocyte cultures with maintenance of a high proliferative capacity up to the second passage. Improved attachment and growth were obtained by seeding primary cells on equine feeder layers. Subcultured keratinocytes showed optimal growth when seeded on collagen type I. The proliferation rate of cells on this substrate exceeded that seen for cells seeded on equine feeder layers. By immunohistochemistry, epithelial origin and state of differentiation of the equine keratinocytes were determined. They expressed keratin and desmoplakin...
Katkiewicz M, Witkowski L, Kita J.The aim of this study was to investigate the structure of lymphatic organs in foals which died due to Rhodococcus equi infection. The material for this study consisted of 9 foals, of both genders, various breeds, 6-14 weeks old. The routine histopathological examination and immunocytochemical reaction for cytokeratine-3 receptors revealed the disturbances in the thymus epithelial cells development. This was manifested by a complete lack of cells expressing cytokeratine-3 receptors, as well as absence of normal thymocytes differentiation. The supposed thymus epithelial cells were very few, expr...
Erickson GA, Maré CJ.Goat Venezuelan equine encephalomyelitis (VEE) antiserum and normal serum were conjugated and evaluated for staining sensitivity and specificity. Cross-staining with either eastern or western equine encephalomyelitis virus-infected cells did not occur. The baby hamster kidney (BHK-21) cell line when combined with highly specific VEE conjugate detected 100 medium suckling mouse intracerebral lethal doses (suckling mouse LD-50/IC) of the 1B subtype of VEE virus per milliliter of equine tissue suspension. Conjugated goat antiserum was assayed for sensitivity for detection of VEE virus-infected eq...
Piccione G, Rizzo M, Arfuso F, Giannetto C, Di Pietro S, Bazzano M, Quartuccio M.During early post-partum period both neonatal foals and peripartum mares are most susceptible to diseases. The aim of this study was to establish physiologic modifications of leukogram during the first month after foaling in mares and their newborn foals. To this end blood samples were collected from nine mares and nine foals (T0-T10), every three days from the 1st day until the 30th day after foaling. Samples were analysed for white blood cell (WBC) count and differential leucocyte counts. Two-way repeated measure analysis of variance (ANOVA) showed, in postpartum mares WBC showed significant...
Wieringa R, De Vries AA, Post SM, Rottier PJ.Equine arteritis virus (EAV) is an enveloped, positive-strand RNA virus belonging to the family Arteriviridae of the order NIDOVIRALES: EAV virions contain six different envelope proteins. The glycoprotein GP(5) (previously named G(L)) and the unglycosylated membrane protein M are the major envelope proteins, while the glycoproteins GP(2b) (previously named G(S)), GP(3), and GP(4) are minor structural proteins. The unglycosylated small hydrophobic envelope protein E is present in virus particles in intermediate molar amounts compared to the other transmembrane proteins. The GP(5) and M protein...
Broström H, Hellström U, Hammarström S, Obel N, Perlmann P.Untreated and neuraminidase-treated equine peripheral blood lymphocytes were analysed for binding of the A hemagglutinin of the snail Helix pomatia (HP). For optimal staining by direct immunofluorescence, the concentration of neuraminidase had to be increased as compared to that needed for other species. Moreover, higher concentrations of HP were required for optimal staining of equine lymphocytes as compared to lymphocytes from other species. Even so, the maximal number of equine lymphocytes exhibiting positive staining was only about 20%. No, or very few, HP-positive lymphocytes were seen wh...
Van Beek H, Baars AJ.Metallothioneins (MTs) were separated and quantitated by reversed-phase high-performance liquid chromatography (RP-HPLC), in direct combination with atomic absorption spectrometry (AAS) for quantitation of the metal contents in MTs. MTs were eluted from an RP-8 column with a gradient of Tris buffer pH 7.0 and methanol, and were detected by UV absorbance (220 nm). Commercially available purified MTs from horse kidney and rabbit liver were analyzed for purity and metal composition. One lot of horse kidney yielded only 50% of the estimated value. In some cases, the certified metal content differe...
Bossart KN, Wang LF, Eaton BT, Broder CC.Hendra virus (HeV) is an emerging paramyxovirus first isolated from cases of severe respiratory disease that fatally affected both horses and humans. Understanding the mechanisms of host cell infection and cross-species transmission is an important step in addressing the risk posed by such emerging pathogens. We have initiated studies to characterize the biological properties of the HeV envelope glycoproteins. Recombinant vaccinia viruses encoding the HeV F and G open reading frames were generated and glycoprotein expression was verified by metabolic labeling and detection using specific antis...
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...
Broström H, Obel N, Perlmann P.Human lymphocytes displayed a frequent natural cytotoxicity (NK) in vitro against normal equine dermal fibroblasts (ED) and against equine tumour cells of a virus-containing cell line (Mc-1). Similarly, human normal sera contained antibodies that induced antibody-dependent cellular cytotoxicity (ADCC) by normal human lymphocytes against the same target cells. Both NK and ADCC varied for different donors. For individual donors, however, cytotoxicity against the two target cells was significantly correlated both in NK and ADCC. For ED there was also a significant correlation between ADCC and NK ...
Godbout M, Vargas A, Hélie P, Bullone M, Lavoie JP.To use a biopolymer delivery system to investigate the ability of interleukin (IL)-4 to recruit neutrophils into subcutaneous tissues of equids. Methods: 16 horses and 2 ponies. Methods: Animals were assigned to 3 experiments (6/experiment). Effects of recombinant equine (Req) IL-4 (100, 250, or 500 ng/site) versus a positive control (ReqIL-8; 100 ng, 250 ng, or 1 μg/site) and a negative control (Dulbecco PBSS or culture medium) on neutrophil chemotaxis were assessed after SC injection into the neck with an injectable biopolymer used as the vehicle. Tissue samples including the biopolymer plu...
Archambault D, St-Louis MC, Martin S.The genome of equine arteritis virus (EAV) produces a 3' coterminal-nested set of six subgenomic (sg) viral RNAs during virus replication cycle, and each set possesses a common leader sequence of 206 nucleotides (nt) in length derived from the 5' end of the viral genome. Given the presence of the leader region within both genomic and sg mRNAs, it is likely to contain cis-acting signals that may interact with cellular or viral proteins for RNA synthesis. Gel mobility shift assays indicated that proteins in Vero cell cytoplasmic extracts formed complexes with the positive (+) and negative (-) st...
Löfgren M, Ekman S, Svala E, Lindahl A, Ley C, Skiöldebrand E.Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and...
Xu J, Cai J, Suresh M, Peek SF, Darien BJ.Equine PSGL-1 (ePSGL-1) is widely expressed on equine PBMC as a homodimer with sialylation (sLeX) modifications that contribute to P-selectin binding affinity. To investigate the role of other potential post-translational modifications required for high-affinity P-selectin binding, ePSGL-1 was transfected into CHO cells expressing equine FucT-VII and/or C2GnT. P-selectin-IgG chimera binding by ePSGL-1 transfected into CHO cells only occurred when both FucT-VII and C2GnT were expressed, establishing that fucosylation and core-2 branching are required as post-translational modifications for high...
Harman RM, Churchill KA, Jager MC, Van de Walle GR.Equid herpesvirus 1 (EHV-1) outbreaks occur when virus spreads from infected horses to in-contact horses, primarily via nasal shedding. This study evaluated the efficacy of factors secreted by equine peripheral blood derived mesenchymal stromal cells (PB-MSCs), collectively named the secretome, to inhibit the growth of EHV-1 in (i) 2D epithelial cell cultures (RK-13) in vitro, (ii) 3D equine nasal explants in vitro and (iii) an EHV-1 infection mouse model in vivo. The PB-MSC secretome was found to inhibit EHV-1 in RK-13 cells as well as in the epithelium of equine nasal explants. Although 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...
Palomino Lago E, Jelbert ER, Baird A, Lam PY, Guest DJ.Persistent inflammation is associated with the poor regeneration of musculoskeletal tissues. Embryonic stem cells (ESCs) have an attenuated response to inflammatory cytokines, but there are mixed reports on the response of induced pluripotent stem cells (iPSCs) to inflammation. Horses provide a relevant large animal model for studying musculoskeletal tissue diseases and the testing of novel therapies. The aim of this study was to determine if equine iPSCs are responsive to the inflammatory cytokines IL-1β, TNFα and IFN-γ in their undifferentiated state, or following differentiation into ten...
Alkhilaiwi F, Wang L, Zhou D, Raudsepp T, Ghosh S, Paul S, Palechor-Ceron N, Brandt S, Luff J, Liu X, Schlegel R, Yuan H.Skin injuries in horses frequently lead to chronic wounds that lack a keratinocyte cover essential for healing. The limited proliferation of equine keratinocytes using current protocols has limited their use for regenerative medicine. Previously, equine induced pluripotent stem cells (eiPSCs) have been produced, and eiPSCs could be differentiated into equine keratinocytes suitable for stem cell-based skin constructs. However, the procedure is technically challenging and time-consuming. The present study was designed to evaluate whether conditional reprogramming (CR) could expand primary equine...
Dern K, van Eps A, Wittum T, Watts M, Pollitt C, Belknap J.Although continuous digital hypothermia (CDH) protects lamellae from injury in the oligofructose (OF) model of sepsis-related laminitis (SRL), conflicting results exist from these studies regarding effects of CDH on lamellar inflammatory events. Objective: To determine the effect of CDH on lamellar inflammatory events in normal and OF-treated horses when instituted at a clinically relevant time point (onset of clinical signs of sepsis in this model). Methods: Standardbred geldings (n = 15) aged 3-11 years were used. Methods: In a randomized, controlled discovery study, animals were administ...
