Mononuclear cells in horses are a type of immune cell that includes lymphocytes and monocytes. These cells are integral components of the equine immune system, participating in the body's defense mechanisms against pathogens. Lymphocytes are involved in the adaptive immune response, while monocytes are part of the innate immune system and can differentiate into macrophages or dendritic cells. Mononuclear cells circulate in the bloodstream and migrate to sites of infection or inflammation, where they perform various functions such as phagocytosis, antigen presentation, and cytokine production. This page compiles peer-reviewed research studies and scholarly articles that explore the characteristics, functions, and clinical relevance of mononuclear cells in equine health.
Noronha LE, Harman RM, Wagner B, Antczak DF.The immunoreceptor NKp46 is considered to be the most consistent marker of NK cells across mammalian species. Here, we use a recombinant NKp46 protein to generate a panel of monoclonal antibodies that recognize equine NKp46. The extracellular region of equine NKp46 was expressed with equine IL-4 as a recombinant fusion protein (rIL-4/NKp46) and used as an immunogen to generate mouse monoclonal antibodies (mAbs). MAbs were first screened by ELISA for an ability to recognize NKp46, but not IL-4, or the structurally related immunoreceptor CD16. Nine mAbs were selected and were shown to recognize ...
Wattrang E, Palm AK, Wagner B.Synthetic oligodeoxyribonucleotides (ODN) may prove useful immune modulators in equine medicine. It is however important to assess the effects of each specific ODN in the species it is intended to be used in. The present study therefore aimed to evaluate some ODN for induction of cytokine production; i.e. type I interferons (IFN), IFN-γ, tumor necrosis factor-α (TNF-α) and transforming growth factor-β (TGF-β), and proliferation of equine peripheral blood mononuclear cells (PBMC). A panel of four ODN containing unmethylated cytosine-guanosine sequences (CpG) was used: ODN 1 and ODN 8 repre...
Sun L, Adams AA, Betancourt A, Stewart JC, Liu C, Horohov DW.Interferon-gamma (IFNγ) plays an important role against viral and intracellular bacterial infections and its production is deficient in foals. Cellular proliferation provides an opportunity for de novo gene expression, though little is known about its role in regulating IFNγ expression in foals. While stimulation of foal peripheral blood mononuclear cells (PBMCs) with concanavalin A (ConA) increased the frequency of IFNγ(+) cells, the overall percentage of IFNγ(+) cells remained below that of adults. By contrast, the proliferative response of foal PBMC was significantly greater than that o...
Hagen J, Hartnett C, Houchins JP, Giguère S, Kalyuzhny AE.Human and mouse immune system cells are the most frequently used specimens in ELISPOT assays. In an effect to expand the application of ELISPOT assay to other species, we developed matched antibody pairs for ready-to-use kits designed for studying the frequency of equine IFNγ- and IL-4-secreting peripheral blood mononuclear cells (PBMCs). Equine PBMCs were stimulated with either concanavalin A (Con A) or calcium ionomycin mixed with phorbol 12-myristate 13-acetate (CaI + PMA). We found that Con A, in general, had a more profound stimulating effect than CaI + PMA on IL-4 secretion, whereas bot...
Liu M, Bordin A, Liu T, Russell K, Cohen N.Focusing on the first 3 weeks of life, this study examined the mRNA transcript development of different Th-type cytokines in foals in response to Rhodococcus equi infection in vitro. Results demonstrated the significant up-regulation in expression of Th1-, Th2-, and Th17-type cytokines (IFN-γ, IL-4, IL-6, IL-8, IL-12p35, IL-12p40, IL-17, IL-23p19, and TNF-α) in R. equi infection of bronchial alveolar lavage (BAL) cells of 10-day-old foals. Consequently, signature cytokines of 3 Th cell types, IFN-γ (Th1), IL-4 (Th2), and IL-17 (Th17), were used to compare temporal response patterns of circu...
Ibrahim S, Steinbach F.Earlier studies investigating the cross-reactivity of antibodies submitted to the HLDA8 had used flow cytometry as a method of choice to screen mAbs for reactivity with equine leukocytes, including two-color flow-cytometry to characterize the lymphocyte population they detect. In addition, immuno-histochemistry (IHC) was used to detect distribution of positive cells in lymphoid tissue sections. In this study we performed immunoprecipitation (IP) to complement the previous results and add valuable information regarding the molecules detected by the cross-reacting antibodies. Surface molecules f...
Pusterla N, Mapes S, Gebhart C.The cell-mediated immune response to Lawsonia intracellularis, the agent of equine proliferative enteropathy (EPE), was investigated in vaccinated and naturally infected foals. Interferon (IFN)-γ gene expression was determined in peripheral blood mononuclear cells collected from vaccinated (n=6) and control foals (n=6) every 30 days for 180 days following first vaccine administration, and from clinically affected foals (n=16) within 7-10 days of diagnosing EPE. Seroconversion (immunoperoxidase monolayer assay titer ≥60) occurred in 5/6 vaccinated foals between 60 and 90 days following the f...
Hamza E, Steinbach F, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis caused by bites of midges from the genus Culicoides. We have shown previously that peripheral blood mononuclear cells (PBMC) from IBH-affected horses produce higher levels of IL-4 and lower levels of IL-10 and TGF-β1 than those from healthy horses, suggesting that IBH is associated with a reduced regulatory immune response. FoxP3 is a crucial marker of regulatory T cells (Tregs). Here we have determined the proportion of CD4(+)CD25(+)FoxP3(+) T cells by flow cytometry in PBMC directly after isolation or after stimulation with Cu...
Brandt S, Schoster A, Tober R, Kainzbauer C, Burgstaller JP, Haralambus R, Steinborn R, Hinterhofer C, Stanek C.Equine hoof canker is a chronic proliferative pododermatitis of as yet unknown aetiology. Like equine sarcoid disease, canker is a therapy-resistant disorder characterised by hyperkeratosis, acanthosis and a marked tendency to recur. Objective: There is an association of sarcoid-inducing bovine papillomaviruses of types 1 and 2 (BPV-1, BPV-2) with hoof canker disease. Methods: Using PCR-based techniques, we assessed canker tissue, intact skin and/or peripheral blood mononuclear cells (PBMCs) of 25 canker-affected horses for the presence of sarcoid-associated BPV-1 and -2. Results: Conventional...
Zhang L, Franchini M, Wehrli Eser M, Dip R.Accumulation of extracellular adenosine has been closely associated with human asthmatic responses. However, the relevance of adenosine signalling in equine airways has not previously been investigated. Objective: To determine the expression of adenosine receptors (AR) in bronchoalveolar lavage (BAL) cells and assess the reactivity of these cells to AR ligands ex vivo, employing IL-6 as readout of adenosinergic inflammatory signalling. Methods: Eight horses with varying degrees of lower airway inflammation and 10 healthy controls were analysed. Expression of AR-subtypes in each BAL sample was ...
Hurley DJ, Berghaus LJ, Hurley KA, Moore JN.To evaluate effects of black walnut extract (BWE) on equine mononuclear cells and determine whether BWE has direct proinflammatory effects. Methods: Mononuclear cells separated from blood samples from 8 horses. Methods: Aqueous BWE was prepared and processed to eliminate contamination with particulates and microbes. A Limulus amoebocyte lysate assay was used to detect lipopolysaccharide (LPS) contamination in the BWE. Mononuclear cells were incubated in minimal essential medium with or without the addition of 0.6% to 10% (vol/vol) BWE. These mononuclear cells were assessed for viability, activ...
Capomaccio S, Cappelli K, Barrey E, Felicetti M, Silvestrelli M, Verini-Supplizi A.It is known that moderate physical activity may have beneficial effects on health, whereas strenuous effort induces a state resembling inflammation. The molecular mechanisms underlying the cellular response to exercise remain unclear, although it is clear that the immune system plays a key role. It has been hypothesized that the physio-pathological condition that develops in athletes subjected to heavy training is caused by derangement of cellular immune regulation. The purpose of the present study was to obtain information on endurance horse gene transcription under strenuous conditions and t...
Capomaccio S, Verini-Supplizi A, Galla G, Vitulo N, Barcaccia G, Felicetti M, Silvestrelli M, Cappelli K.A large proportion of mammalian genomes is represented by transposable elements (TE), most of them being long interspersed nuclear elements 1 (LINE-1 or L1). An increased expression of LINE-1 elements may play an important role in cellular stress-related conditions exerting drastic effects on the mammalian transcriptome. To understand the impact of TE on the known horse transcriptome, we masked the horse EST database, pointing out that the amount is consistent with other major vertebrates. A previously developed transcript-derived fragments (TDFs) dataset, deriving from exercise-stimulated hor...
Wilsterman S, Soboll-Hussey G, Lunn DP, Ashton LV, Callan RJ, Hussey SB, Rao S, Goehring LS.Infection with equine herpesvirus-1 (EHV-1) causes respiratory disease, late term abortions and equine herpesvirus myeloencephalitis (EHM) and remains an important problem in horses worldwide. Despite increasing outbreaks of EHM in recent years, our understanding of EHM pathogenesis is still limited except for the knowledge that a cell-associated viremia in peripheral blood mononuclear cells (PBMCs) is a critical link between primary respiratory EHV-1 infection and secondary complications such as late-term abortion or EHM. To address this question our objective was to identify which PBMC subpo...
Kabithe E, Hillegas J, Stokol T, Moore J, Wagner B.CD14 is a receptor for the complex of lipopolysaccaride (LPS) and LPS-binding protein. Binding of this complex to CD14 in association with Toll-like receptor 4 provides a major pathway for the initiation of innate immune responses to bacterial pathogens. We used a mammalian expressed extracellular region of equine CD14 (rCD14) derived from an IgG fusion protein to produce monoclonal antibodies (mAbs) to CD14. Eight mAbs were tested by flow cytometric analysis of equine leukocytes and by immunoblotting using rCD14 indicating that the mAbs recognized at least three different epitopes on equine C...
Tong T, Bai Y, Liu G, Wang Q, Zhang W, Xiao Y, Xu S, Liu N, Yang T, Wu D.IL-18 is a cytokine originally discovered as an important modulator of immune responses and subsequently shown to be pleiotropic. In this report, we expressed the recombinant equine mature interleukin-18 (rEMIL-18) in E. coli and purified it by nickel affinity gel column chromatography. Purified rEMIL-18 had biological activity commensurate with recombinant human IL-18, as determined by its synergistic effect with recombinant human IL-12 (rhIL-12) on the induction of IFN-gamma gene expression in equine peripheral blood mononuclear cells (PBMC). Following intraperitoneal (i.p.) immunization of ...
Paillot R, Robinson C, Steward K, Wright N, Jourdan T, Butcher N, Heather Z, Waller AS.Streptococcus equi is the causative agent of strangles, the most frequently diagnosed infectious disease of horses worldwide. The disease is characterized by abscessation and swelling of the lymph nodes of the head and neck, which can literally strangle the horse to death. S. equi produces four recently acquired phage-associated bacterial superantigens (sAgs; SeeH, SeeI, SeeL, and SeeM) that share homology with the mitogenic toxins of Streptococcus pyogenes. The aim of this study was to characterize the contribution of each of these S. equi sAgs to mitogenic activity in vitro and quantify the ...
Hamza E, Torsteinsdottir S, Eydal M, Frey CF, Mirkovitch J, Brcic M, Wagner B, Wilson AD, Jungi TW, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland where Culicoides are absent. However, following importation into continental Europe where Culicoides are present, >or=50% of Icelandic horses (1st generation) develop IBH but
Cappelli K, Felicetti M, Capomaccio S, Pieramati C, Silvestrelli M, Verini-Supplizi A.The stress response is a critical factor in the training of equine athletes; it is important for performance and for protection of the animal against physio-pathological disorders.In this study, the molecular mechanisms involved in the response to acute and strenuous exercise were investigated using peripheral blood mononuclear cells (PBMCs). Results: Quantitative real-time PCR (qRT-PCR) was used to detect modifications in transcription levels of the genes for matrix metalloproteinase-1 (MMP-1) and interleukin 8 (IL-8), which were derived from previous genome-wide expression analysis. Signific...
Zhang YW, Davis EG, Bai J.Quantitative reverse transcription polymerase chain reaction (RT-PCR) has become a basic, reliable and sensitive modern technique, in both biological research and clinical diagnosis, for investigation of gene expression and validation of cDNA microarray analysis. Accurate mRNA quantification using quantitative RT-PCR commonly requires data normalization through stable housekeeping genes (HKGs). Selection of HKGs for data normalization is critical for accurate mRNA quantification. Our objective was to evaluate a set of candidate HKGs as internal controls for gene expression studies using quanti...
Treonze KM, Alves K, Fischer P, Hagmann WK, Hora D, Kulick A, Vakerich K, Smith ND, Lingham RB, Maniar S, Reger TS, Zunic J, Munoz B, Prasit P....The purpose of this study was to characterize the alpha(4)beta(1) receptor (CD49d/CD29, very late antigen-4, VLA-4) on circulating equine leukocytes and to evaluate the intrinsic potency of an alpha(4)beta(1) receptor antagonist (Compound B) in the horse. Ultimately, these studies would allow us to determine the suitability of treating recurrent airway obstruction (RAO; heaves) affected horses by blocking the cellular recruitment of lymphocytes and neutrophils into the lung. The data demonstrates the alpha(4)beta(1) integrin is present on horse lymphocytes and neutrophils (fluorescence-assiste...
Liu T, Nerren J, Liu M, Martens R, Cohen N.Neonates are thought to be generally deficient in production of Th-1-associated cytokines at birth, and thereby more susceptible to bacterial infections. Using neonatal foals as a model, this study examined the age-dependent maturation of both basal and stimulus-induced immune responses, as reflected by the expression of a panel of Th-1-associated and pro-inflammatory cytokines. Results showed that although the basal production of IFN-gamma and IL-6 was impaired (P<0.05) in PBMCs of neonatal foals at birth, the basal production of IL-8, IL-12(p35/p40) and IL-23(p19/p40) were either in exces...
Lin YZ, Deng XL, Shen N, Lü XL, Zhao LP, Kong XG, Shao YM, Zhou JH.To develop a flow cytometry using (5-carboxyfluorescein diacetate succinmidyl ester, CFSE) to detect the proliferation of specific T lymphocytes from equine infectious anemia virus (EIAV). Methods: Peripheral blood mononuclear cells (PBMC) were isolated, stained with CFSE and incubated with EIAV for 5 days. After interacted with either CD4(+) or CD8(+) antibody, the cells were detected for proliferated population, which contained serially 2-fold reduced CFSE in CD4(+) and CD8(+) T lymphocytes. Results: The concentration of CFSE, and the type, concentration and reaction time of EIAV-specific an...
Wagner B, Freer H.The detection and quantification of equine cytokines has been hampered by the lack of antibodies for many years. With the development of antibody pairs for equine cytokines during the past years, the quantification of these essential regulators of the immune response became possible. After being successfully tested by enzyme-linked immunosorbent assays (ELISA), three of these anti-cytokine reagents were used here to establish the first cytokine multiplex assay for equine IL-4, IL-10 and IFN-alpha. A fluorescent bead-based system was used as matrix for this assay that allows the simultaneous de...
Bailat AS, Soutullo AR, García MI, Veaute CM, Garcia L, Racca AL, Malan Borel IS.Gp90 and gp45 synthetic peptides, which mimic conserved sequences of native viral proteins, are recognized by antibodies to equine infectious anemia virus (EIAV) in asymptomatic carrier horses and generate humoral and cellular responses in immunized mice. Cytokine mRNA levels were evaluated in equine peripheral blood mononuclear cells (PBMCs) after in vitro stimulation with gp90 and gp45 with the aim of determining the cytokine profile associated with the proliferative response. Stimulation index (SI) values indicate that 100 and 60% of EIAV-infected horses recognized gp90 and gp45, respective...
Dietze B, Cierpka E, Schäfer M, Schill W, Lutz MB.Equine dendritic cells (eqDC) can be generated from peripheral blood monocytes by propagation in GM-CSF and IL-4. Despite similarities with the generation of human DC, we found significant improvements for eqDC generation and functional influences on eqDC maturation. The fractionation of peripheral blood mononuclear cells (PBMC) by two subsequent gradients at densities of 1.090 and 1.077 as well as an adherence step in AIM V((R)) medium on dishes coated with extracellular matrix components (Primaria) improved the purity and yield of DC. After 3 days, eqDC cultures with GM-CSF alone developed i...
Lin Y, Deng X, Shen N, Zhao L, Meng Q, Max J, Wang J, Shao Y, Zhou J.The attenuated vaccine of equine infectious anemia virus (EIAV) is the first lentiviral vaccine that provides solid protection against the infection of EIAV virulent strains. Study of the immune response induced by EIAV vaccine is an important approach to understand the immunity to other lentiviruses. IFN-gamma expressed by specifically stimulated lymphocytes is an important indicator for the evaluation of T cell-mediated immunity. A flow cytometry based assay was established in this study to accurately and effectively detect IFN-gamma expression in different subtypes of T lymphocytes in EIAV-...
Horohov DW, Breathnach CC, Sturgill TL, Rashid C, Stiltner JL, Strong D, Nieman N, Holland RE.While immune modulators are used routinely in equine medicine, their mechanism of action is not always known. Objective: To determine the effect of a commercial preparation of inactivated parapoxvirus ovis (Orf virus; PPVO) on cytokine gene expression by equine peripheral blood mononuclear cells (PBMC) both in vitro and in vivo. Methods: PBMC were prepared from 6 mixed-breed yearlings and cultured in vitro with PPVO with or without Concanavalin A (Con A) for 24 h. Effects on the expression of IFNalpha, IFNbeta IFNgamma, TNFalpha and IL-18 were analysed by real time quantitative PCR (RT-PCR). I...
Brandt S, Haralambus R, Schoster A, Kirnbauer R, Stanek C.Bovine papillomaviruses of types 1 and 2 (BPV-1 and -2) chiefly contribute to equine sarcoid pathogenesis. However, the mode of virus transmission and the presence of latent infections are largely unknown. This study established a PCR protocol allowing detection of <or=10 copies of the BPV-1/-2 genes E5 and L1. Subsequent screening of peripheral blood mononuclear cell (PBMC) DNA derived from horses with and without BPV-1/2-induced skin lesions demonstrated the exclusive presence of E5, but not L1, in PBMCs of BPV-1/2-infected equines. To validate this result, a blind PCR was performed from ...
Cook RF, Cook SJ, Even DL, Schaffer C, Issel CJ.Horse IL-7 (HIL-7) cDNA was isolated from adult lymph node tissue by reverse transcription polymerase chain reaction (RT-PCR) using oligonucleotide primers based on horse genomic sequences (The Broad Institute). In addition, to the full-length (FL) 531bp reading frame encoding 176 amino acids, shorter open-reading frames of 477, 396 and 264bp were also amplified. Nucleotide sequence analysis of these RT-PCR products demonstrated they were homologous except the shorter species were missing internal sequences consistent with multiple RNA splicing events. Consequently, the shorter open-reading fr...
Dietze B, Cierpka E, Schäfer M, Schill W, Lutz MB.Equine dendritic cells (eqDC) can be generated from peripheral blood monocytes by propagation in GM-CSF and IL-4. Despite similarities with the generation of human DC, we found significant improvements for eqDC generation and functional influences on eqDC maturation. The fractionation of peripheral blood mononuclear cells (PBMC) by two subsequent gradients at densities of 1.090 and 1.077 as well as an adherence step in AIM V((R)) medium on dishes coated with extracellular matrix components (Primaria) improved the purity and yield of DC. After 3 days, eqDC cultures with GM-CSF alone developed i...
Bonin CP, Baccarin RY, Nostell K, Nahum LA, Fossum C, de Camargo MM.Engagement of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) is a master trigger of the deleterious effects of septic shock. Horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. Analysis of tlr4 promoters revealed high similarity among LPS-sensitive species (human, chimpanzee, and horse) and low similarity with LPS-resistant species (mouse and rat). Four conserved nuclear factor kappa B (NFκB) binding sites were found in the tlr4 promoter and two in the md2 promoter sequences that are likely to be t...
Legere RM, Poveda C, Ott JA, Bray JM, Villafone EG, Silveira BPD, Kahn SK, Martin CL, Mancino C, Taraballi F, Criscitiello MF, Berghman L, Bordin AI....Design and evaluate immune responses of neonatal foals to a mRNA vaccine expressing the virulence-associated protein A (VapA) of Rhodococcus equi. Methods: Cultured primary equine respiratory tract cells; Serum, bronchoalveolar lavage fluid (BALF), and peripheral blood mononuclear cells (PBMCs) from 30 healthy Quarter Horse foals. Methods: VapA expression was evaluated by western immunoblot in cultured equine bronchial cells transfected with 4 mRNA constructs encoding VapA. The mRNA construct with greatest expression was used to immunize foals at ages 2 and 21 days in 5 groups: (1) 300 μg neb...
Iribarne A, Palma MB, Andrini L, Riccillo F, Rodriguez D, Casella M, Garay F, Zabala JS, Mazza L, Muro A, Buero G, Miriuka SG, Carosella E, García MN.Wound healing after skin injury is a complex process, particularly in equines where leg wounds are prevalent and their repair is complicated due to the anatomical characteristics. Conventional treatments are not effective enough. The umbilical cord offers an unlimited source of adult mesenchymal stem cells (ucMSCs) from Wharton's jelly tissue. The present study aims to demonstrate the safety and therapeutic potential of the allogeneic use of equine ucMSCs (e-ucMSCs) in the healing of severe equine leg wounds. The methods employed were the isolation, culture and expansion of e-ucMSCs. Flow cyto...
Witkowska-Piłaszewicz O, Pingwara R, Szczepaniak J, Winnicka A.Clenbuterol, the β2-adrenoceptor agonist, is gaining growing popularity because of its effects on weight loss (i.e., chemical liposuction). It is also popular in bodybuilding and professional sports, due to its effects that are similar to anabolic steroids. However, it is prohibited by anti-doping control. On the other hand, it is suggested that clenbuterol can inhibit the inflammatory process. The cells from 14 untrained and 14 well-trained race horses were collected after acute exercise and cultured with clenbuterol. The expressions of CD4, CD8, FoxP3, CD14, MHCII, and CD5 in PBMC, and reac...
Parkinson NJ, Buechner-Maxwell VA, Witonsky SG, Pleasant RS, Werre SR, Ahmed SA.The innate immune response to lipopolysaccharide contributes substantially to the morbidity and mortality of gram-negative sepsis. Horses and humans share an exquisite sensitivity to lipopolysaccharide and thus the horse may provide valuable comparative insights into this aspect of the inflammatory response. MicroRNAs, small non-coding RNA molecules acting as post-transcriptional regulators of gene expression, have key roles in toll-like receptor signaling regulation but have not been studied in this context in horses. The central hypothesis of this study was that lipopolysaccharide induces di...
Schumann B, Winkler J, Mickenautsch N, Warnken T, Dänicke S.Both deoxynivalenol (DON), zearalenone (ZEN), and their metabolites are known to modulate immune cells in various species whereby viability and proliferation are influenced. Such effects were rarely examined in horses. Therefore, one aim of the present study was to titrate the inhibitory concentrations of DON, 3-acetyl-DON (3AcDON), de-epoxy-DON (DOM-1), ZEN, and α- and β-zearalenol (ZEL) at which viability and proliferation of equine PBMC were reduced by 50 % (IC50) and 10 % (IC10) in vitro. For evaluation of practical relevance of the in vitro findings, a further aim was to screen horses...
Hatzel JN, Bouma GJ, Cleys ER, Bemis LT, Ehrhart EJ, McCue PM.Early pregnancy factor has been identified as a 10-kDa extracellular homolog of heat shock protein 10 (Hsp10). Hsp10 has been detected during early pregnancy in serum of mice, sheep, pigs, horses, cows, and humans by the rosette inhibition test. Hsp10 has also been associated with several neoplastic and autoimmune diseases. The goal of the present study was to determine if Hsp10 could be detected in the early equine embryo through the use of immunohistochemistry and quantitative real-time PCR. Additionally, analysis of systemically harvested peripheral blood mononuclear cells (PBMCs) from both...
Schnabel CL, Babasyan S, Freer H, Wagner B.C-X-C motif ligand 10 (CXCL10) is a pro-inflammatory chemokine and has been extensively evaluated in people and mice. In horses, CXCL10 and its involvement in host immunity has rarely been analyzed due to the lack of specific antibodies. We generated a mAb specific for the equine chemokine CXCL10 using hybridoma technology. Antibody specificity was confirmed by intracellular staining and flow cytometric analysis of Chinese Hamster Ovary (CHO) cells expressing equine rCXCL10, while CHO cells expressing equine rCXCL9 were not detected. Native CXCL10 expression in PBMC from horses of different ag...
Dahlgren AR, Knych HK, Arthur RM, Durbin-Johnson BP, Finno CJ.Recombinant human erythropoietin (rHuEPO) is a well-known performance enhancing drug in human athletes, and there is anecdotal evidence of it being used in horse racing for the same purpose. rHuEPO, like endogenous EPO, increases arterial oxygen content and thus aerobic power. Micro-doping, or injecting smaller doses over a longer period of time, has become an important concern in both human and equine athletics since it is more difficult to detect. Horses offer an additional challenge of a contractile spleen, thus large changes in the red blood cell mass occur naturally. To address the challe...
Hansen S, Baptiste KE, Fjeldborg J, Betancourt A, Horohov DW.An imbalance in various cytokine mRNA expression in bronchoalveolar lavage (BAL) and peripheral blood mononuclear cells (PBMC) in horses suffering from recurrent airway obstruction (RAO) has been demonstrated; however, the natural variation of cytokine expression in healthy horses has yet to be described. The objectives of this study were to: (1) identify age-related differences in the expression of pro-inflammatory cytokines in BAL and PBMC, (2) compare the expression of pro-inflammatory cytokines between BAL and PBMC, and (3) evaluate the relationship between BAL pro-inflammatory cytokine ex...
Davis EG, Rush BR, Blecha F.Immunomodulation with Propionibacterium acnes is used for prophylaxis of respiratory disease or in horses suffering from chronic pulmonary inflammation; however, the mechanism for this response is poorly understood. Semiquantitative reverse transcriptase-polymerase chain reaction assays were used to evaluate gene expression of interleukin (IL)-2, IL-10, interferon (IFN)-gamma, and NK-lysin in healthy horses treated with P. acnes. Findings in the study indicated that horses treated with a P. acnes-based immunomodulator exhibited increased IFN-gamma and NK-lysin gene expression in peripheral blo...
Gupta S, Vohra S, Sethi K, Gupta S, Bera BC, Kumar S, Kumar R.High cytotoxicity and increasing resistance reports of existing chemotherapeutic agents against T. evansi have raised the demand for novel, potent, and high therapeutic index molecules for the treatment of surra in animals. In this regard, repurposing approach of drug discovery has provided an opportunity to explore the therapeutic potential of existing drugs against new organism. With this objective, the macrocyclic lactone representative, ivermectin, has been investigated for the efficacy against T. evansi in the axenic culture medium. To elucidate the potential target of ivermectin in T. ev...
Liu SA, Haque M, Stanfield B, Andrews FM, Roy AA, Kousoulas KG.West Nile Virus (WNV) is endemic in the US and causes severe neurologic disease in horses since its introduction in 1999. There is no effective pharmaceutical treatment for WNV infection rendering vaccination as the only approach to prevention and control of disease. The purpose of this study was to evaluate a recombinant vaccine containing domain III (DIII) of the WNV envelope glycoprotein with and without a natural adjuvant equine (CD40L) in producing virus neutralizing antibodies in horses. Serum IgG1 concentration in the groups of horses vaccinated with the DIII-CD40L+TiterMax and DIII-CD4...
Dunowska M, Meers J, Johnson RD, Wilks CR.Representational difference analysis (RDA) was used to compare gene expression in equine mononuclear cells either infected with equine herpesvirus-2 (EHV-2) or adsorbed with inactivated EHV-2. Seven clones identified in non-infected cells after three rounds of selective subtraction and enrichment for differentially expressed genes contained sequences homologous to equine monocyte chemoattractant protein 1 (MCP-1). This suggested that EHV-2 may down-regulate MCP-1 transcription in infected cells. These findings correlate well with similar findings described for human cytomegalovirus and support...
Vecchione A, Catchpole B, D'Mello F, Kanellos T, Hamblin A.Dendritic cells (DCs) are antigen presenting cells that potently modulate immune responses with varying outcomes depending on the DC sub-population involved. To understand how DC sub-types arise, it is necessary to determine which factors influence their differentiation. At least three major sub-populations of DCs have been described in mice: CD4+/CD8- "myeloid" DCs, CD4-/CD8+ "lymphoid" DCs and Langerhans cell-derived DCs. Whilst somewhat comparable populations have been described in man, in most other species very little is known. The identification of cytokines which stimulate proliferation...
Hodgin EC, McGuire TC, Perryman LE, Grant BD.Delayed hypersensitivity (DH) responses of normal and immunodeficient horses were evaluated with antigens [dinitrochlorobenzene (DNCB), keyhole limpet hemocyanin (KLH)] and phytolectins [phytohemagglutinin (PHA), concanavalin A (Con A)]. Immunologically normal horses sensitized with 5 daily applications of 2 mg of DNCB developed positive skin reactions upon challenge with 0.4 mg of DNCB. The delayed onset of the reaction and the predominately mononuclear cell infiltration at the test site indicated these were DH reactions. Normal horses sensitized with 500 microgram of KLH and challenged with ...
Wattrang E, Berg M, Magnusson M.This study aimed to evaluate different nucleic acid preparations as cytokine inducers in equine cells. To induce cytokine production, bacterial plasmid DNA or short synthetic oligodeoxyribonucleotides (ODN), with or without the transfection reagent lipofectin, were added to cultures of purified equine peripheral blood mononuclear cells (PBMC). Cytokine activity was detected with bioassays in cell culture supernatants after 24h of induction and cytokine mRNA expression was detected using RT-PCR at 6h post induction. For IFN-alpha/beta it was found that both plasmid DNA and phosphodiester ODN, c...
Mißbach S, Aleksic D, Blaschke L, Hassemer T, Lee KJ, Mansfeld M, Hänske J, Handler J, Kammerer R.The CEA gene family is one of the most rapidly evolving gene families in the human genome. The founder gene of the family is thought to be an ancestor of the inhibitory immune checkpoint molecule CEACAM1. Comprehensive analyses of mammalian genomes showed that the CEA gene family is subject to tremendous gene family expansion and contraction events in different mammalian species. While in some species (e.g. rabbits) less than three CEACAM1 related genes exist, were in others (certain microbat species) up to 100 CEACAM1 paralogs identified. We have recently reported that the horse has also an e...
Carlier S, Depuydt E, Van Hecke L, Martens A, Saunders J, Spaas JH.Mesenchymal stem cells provide a valuable treatment option in orthopedic injuries in horses. Unassigned: The aim of this study was to evaluate the hematological, biochemical, immunological and immunomodulatory parameters following intralesional treatment with tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in client-owned horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. Unassigned: The immunogenicity and immunomodulatory capacities of tpMSCs were assessed in a modified mixed lymphocyte re...
Pusterla N, Mapes S, Gebhart C.The cell-mediated immune response to Lawsonia intracellularis, the agent of equine proliferative enteropathy (EPE), was investigated in vaccinated and naturally infected foals. Interferon (IFN)-γ gene expression was determined in peripheral blood mononuclear cells collected from vaccinated (n=6) and control foals (n=6) every 30 days for 180 days following first vaccine administration, and from clinically affected foals (n=16) within 7-10 days of diagnosing EPE. Seroconversion (immunoperoxidase monolayer assay titer ≥60) occurred in 5/6 vaccinated foals between 60 and 90 days following the f...
Faber E, Tshilwane SI, Kleef MV, Pretorius A.African horse sickness (AHS) is caused by African horse sickness virus (AHSV), a double stranded RNA (dsRNA) virus of the genus Orbivirus, family Reoviridae. For the development of new generation AHS vaccines or antiviral treatments, it is crucial to understand the host immune response against the virus and the immune evasion strategies the virus employs. To achieve this, the current study used transcriptome analysis of RNA sequences to characterize and compare the innate immune responses activated during the attenuated AHSV serotype 4 (attAHSV4) (in vivo) and the virulent AHSV4 (virAHSV4) (in...
Durán MC, Willenbrock S, Carlson R, Feige K, Nolte I, Murua Escobar H.CD14 positive (CD14+) cells are the precursor cells of monocyte-derived dendritic cells (DCs). In horses their potent antigen-presenting capacity and ability to induce an effective immune response classify these cells suitable for several therapeutic approaches such as for equine sarcoid. However, in horses, the generation efficiency of DCs from adherent peripheral blood mononuclear cells (PBMCs) is currently still poor. Objective: Establishment of a simple short protocol to enhance DC generation in horses by using a human CD14 monoclonal antibody (mAb) and an automated magnetic activated cell...
Vendrig JC, Coffeng LE, Fink-Gremmels J.Dietary supplementation with oligosaccharides has been proven to be beneficial for health in several mammalian species. Next to prebiotic effects resulting in a modulation of gut micro biota, immunomodulatory effects of oligosaccharides have been documented in vivo. Supplementation with defined oligosaccharide fractions has been shown to attenuate allergic responses and enhance defensive immune responses. Despite the accumulating evidence for immunomodulatory effects, very limited information is available regarding the direct mechanism of action of oligosaccharides. This study aims to elucidat...
Manuja A, Kumar P, Kumar R, Kumar B, Singha H, Sharma RK, Yadav SC.Trypanosoma evansi is the causative agent of surra, which is the most common and widespread trypansomal disease. The infection is mainly restricted to animals, but it has also been documented in human. Trypanosomes possess the thick immunogenic surface coat known as variant surface glycoprotein (VSG). The parasite modifies the VSG constantly resulting in continuous antigenic variations and thus evades the host immune response. Due to antigenic variations, vaccination against trypanosomosis is not useful. Therefore, alternate strategies to augment the immune response are required. CpG-ODN class...
Lonning SM, Zhang W, McGuire TC.Antigen-specific T-helper (Th) lymphocytes are critical for the development of antiviral humoral responses and the expansion of cytotoxic T lymphocytes (CTL). Identification of relevant Th lymphocyte epitopes remains an important step in the development of an efficacious subunit peptide vaccine against equine infectious anemia virus (EIAV), a naturally occurring lentivirus of horses. This study describes Th lymphocyte reactivity in EIAV carrier horses to two proteins, p26 and p15, encoded by the relatively conserved EIAV gag gene. Using partially overlapping peptides, multideterminant and poss...
Vendrig JC, Coffeng LE, Fink-Gremmels J.Increasing evidence suggests that reactions to lipopolysaccharide (LPS), particularly in the gut, can be partly or completely mitigated by colostrum- and milk-derived oligosaccharides. Confirmation of this hypothesis could lead to the development of new therapeutic concepts. Objective: To demonstrate the influence of equine colostral carbohydrates on the inflammatory response in an in vitro model with equine peripheral blood mononuclear cells (PBMCs). Methods: Carbohydrates were extracted from mare colostrum, and then evaluated for their influence on LPS-induced inflammatory responses in PBMCs...
Duran MC, Willenbrock S, Müller JM, Nolte I, Feige K, Murua Escobar H.Interleukin-12 (IL-12) and interferon gamma (IFN-γ) are key cytokines in immunemediated equine melanoma therapy. Currently, a method for accurate simultaneous quantification of these equine cytokines is lacking. Therefore, we sought to establish an assay that allows for accurate and simultaneous quantification of equine IL-12 (eIL-12) and IFN-γ (eIFN-γ). Methods: Several antibodies were evaluated for cross-reactivity to eIL-12 and eIFN-γ and were used to establish a bead-based Luminex assay, which was subsequently applied to quantify cytokine concentrations in biological samples. Results: ...
Tschetter JR, Davis WC, Perryman LE, McGuire TC.Eight murine monoclonal antibodies (mAb) were used to identify the equine CD8 alpha or CD8 beta chains and to define the expression of these chains on lymphocytes from various lymphoid tissues. CD8 alpha was a 39 kDa protein and CD8 beta was a 32 kDa protein. Both chains were expressed on most of the CD8+ T lymphocytes in the peripheral blood, spleen, thymus, mesenteric lymph nodes and ileal intraepithelial lymphocytes (IEL), however, in each lymphoid compartment a percentage of lymphocytes expressed only the CD8 alpha chain. The largest percentage of CD8 alpha alpha expressing T lymphocytes w...
Cassart D, Fett T, Sarlet M, Baise E, Coignoul F, Desmecht D.The morphopathological picture of a subset of equine myopathies is compatible with a primary mitochondrial disease, but functional confirmation in vivo is still pending. The cationic dye JC-1 exhibits potential-dependent accumulation in mitochondria that is detectable by a fluorescence shift from green to orange. As a consequence, mitochondrial membrane potential can be optically measured by the orange/green fluorescence intensity ratio. A flow cytometric standardized analytic procedure of the mitochondrial function of equine peripheral blood mononuclear cells is proposed along with a critical...