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1.
Understanding the immune dynamics in the respiratory mucosa of calves is necessary for a good management of bovine respiratory disease. Immune dynamics in the respiratory mucosa in humans and experimental animals has been assessed by flow cytometric analysis of bronchoalveolar lavage fluid (BALF); however, few reports have addressed this subject in calves. The aim of this study was to establish a universal method to analyze bronchoalveolar lavage fluid (BALF) by flow cytometry and to obtain basic knowledge of bovine respiratory mucosal immune dynamics. We investigated the immune cell populations in BALF and evaluated the surface antigen expression of alveolar macrophages in calves using flow cytometer. To further analyze the surface antigen variation observed in alveolar macrophages in detail, stimulation assays were performed in vitro. BALF cells were separated into three distinct populations based on their light scatter plot, which were considered to be macrophages, lymphocytes, and neutrophils. In most individuals, most of the BALF immune cells were alveolar macrophages, but an increased proportion of lymphocytes and neutrophils was observed in some individuals. Analysis of each surface antigen expression in alveolar macrophages showed that CD21 and MHC class II expression changed in response to changes in the leukocyte population. Moreover, when alveolar macrophages were stimulated with interferon-γ in vitro, the expression of CD21 was drastically reduced and MHC class II was increased, suggesting that functional changes in alveolar macrophages themselves are involved in the immune dynamics.  相似文献   

2.
Interferences caused by bilirubin, hemolysis, and lipemia on 25 clinical chemistry analytes in bovine, canine, equine, and feline sera were studied using the Coulter Dacos and commercial reagents. We present the data as “interferograms”, which show the anticipated percent change in serum analyte activity or concentration with varying concentrations of bilirubin, hemoglobin, or lipid. Obvious species differences in response to at least one added interfering substance were found for alanine aminotransferase, aspartate aminotransferase, cholesterol, creatine kinase, globulin, total protein, and urea. The remaining analytes were affected in a linear or complex dose-response relationship or were only affected at the highest concentrations of interfering substances. These data will be useful in aiding interpretation of laboratory test results when common interferences are present in the serum.  相似文献   

3.
Mastitis, inflammation of the mammary tissue, is a common disease in dairy animals and mammary pathogenic Escherichia coli (MPEC) is a leading cause of the disease. Lipopolysaccharide (LPS) is an important virulence factor of MPEC and inoculation of the mammary glands with bacterial LPS is sufficient to induce an inflammatory response. We previously showed using adoptive transfer of normal macrophages into the mammary gland of TLR4-deficient C3H/HeJ mice that LPS/TLR4 signaling on mammary alveolar macrophages is sufficient to elicit neutrophil recruitment into the alveolar space. Here we show that TLR4-normal C3H/HeN mice, depleted of alveolar macrophages, were completely refractory to LPS intramammary challenge. These results indicate that alveolar macrophages are both sufficient and essential for neutrophil recruitment elicited by LPS/TLR4 signaling in the mammary gland. Using TNFα gene-knockout mice and adoptive transfer of wild-type macrophages, we show here that TNFα produced by mammary alveolar macrophages in response to LPS/TLR4 signaling is an essential mediator eliciting blood neutrophil recruitment into the milk spaces. Furthermore, using the IL8 receptor or IL1 receptor gene-knockout mice we observed abrogated recruitment of neutrophils into the mammary gland and their entrapment on the basal side of the alveolar epithelium in response to intramammary LPS challenge. Adoptive transfer of wild-type neutrophils to IL1 receptor knockout mice, just before LPS challenge, restored normal neutrophil recruitment into the milk spaces. We conclude that neutrophil recruitment to the milk spaces is: (i) mediated through TNFα, which is produced by alveolar macrophages in response to LPS/TLR4 signaling and (ii) is dependent on IL8 and IL1β signaling and regulated by iNOS-derived NO.  相似文献   

4.
Examination of the C24V (Oregon) and MAC A (Ontario) strains of bovine viral diarrhea viruses have shown them to be ribonucleic acid containing viruses, with essential lipid and having compound helical symmetry with the diameter of the helix being in the neighbourhood of 180 A. Because of these properties it is suggested that the virus should be considered a member of the Myxovirus group. Hog cholera virus is related to bovine viral diarrhea virus by means of a “soluble” antigen, and also possesses essential lipid. It is therefore suggested that hog cholera virus represents still another veterinary myxovirus.  相似文献   

5.
The effect of bovine respiratory syncytial virus (BRSV) upon alveolar macrophage (AM) function was investigated using an in vivo calf inoculation model. Alveolar macrophages were collected sequentially from live calves at multiple time points during the 14 day period following viral inoculation. Alveolar macrophages from bronchoalveolar lavage fluids were purified by density gradient centrifugation (> 95% AM) prior to in vitro evaluation of cell functions. There were significant but variable and inconsistent differences in the functions of AM from the BRSV inoculated calves compared to the control calves. Fc-receptor mediated phagocytosis was either increased or unchanged by BRSV inoculation. Nonopsonized phagocytosis was decreased during the early postinoculation period and later increased. There was a variable effect on AM phagosome lysosome fusion with increased fusion activity on postinoculation days 2 through 5, 7 and 12 but reduced activity on days 6 and 10. The AM respiratory burst, as measured by nitroblue tetrazolium dye reduction, was essentially unaffected with a reduction in activity on day 10 only. In this model, BRSV inoculation of calves primarily resulted in an alteration of the membrane associated phagocytic functions of the alveolar macrophages (p < 0.05).  相似文献   

6.
Mastitis, the inflammation of the mammary gland, is an important disease affecting dairy animals worldwide. The disease is caused by mammary pathogenic bacteria and Escherichia coli are frequently implicated. Virulence factors of mammary pathogenic E. coli are only partially known and intramammary challenge with LPS elicits neutrophil recruitment in experimental bovine and murine mastitis models. We have previously shown that neutrophil recruitment in LPS-induced murine mastitis is strictly dependent on mammary alveolar macrophages. However, the relative role of alveolar macrophages and blood neutrophils in E. coli mastitis is not well defined. To this end, we selectively depleted mammary alveolar macrophages or blood neutrophils before intramammary challenge with E. coli strain P4 (ECP4). Mice depleted of alveolar macrophages prior to intramammary challenge recruited neutrophils normally and restricted bacterial growth and interstitial invasion. Importantly however, upon depletion of alveolar macrophages, ECP4 invaded the mammary alveolar epithelial cells and formed intracellular bacterial communities. In contrast, neutrophil depletion prior to intramammary infection with ECP4 was associated with unrestricted bacterial growth, tissue damage, severe sepsis and mortality. This study suggests that neutrophils but not alveolar macrophages provide essential antimicrobial defense against mammary pathogenic E. coli. Furthermore, we show here similar invasion after depletion of alveolar macrophages as in our previous studies showing that LPS/TLR4 signaling on alveolar macrophages abrogates ECP4 invasion of the mammary epithelium. Interestingly, similar ECP4 invasion and formation of intracellular communities were also observed following intramammary infection of either iNOS gene-deficient or IL-1 receptor type 1 gene-deficient mice.  相似文献   

7.
Tilmicosin is a potent antimicrobial with broad-spectrum activity against the bacterial agents involved in the bovine respiratory disease complex. Recent studies indicate that in addition to being bactericidal, tilmicosin is capable of modulating inflammation in the lung. A series of experiments were designed to determine whether tilmicosin alters alveolar macrophage-prostaglandin E(2) (PGE(2)) production induced by Escherichia coli (O55:B5) lipopolysaccharide (LPS). Twenty-two healthy Holstein bull calves were used to study the effects of LPS-induced PGE(2) production of alveolar macrophages after in vivo or in vitro treatment with tilmicosin. In Experiment 1, tilmicosin was given by subcutaneous injection (15 mg/kg) twice, 48 hours apart, to four calves; four control calves received no treatment. Twenty-four hours after the second treatment, alveolar macrophages were stimulated with LPS in vitro. In Experiment 2, alveolar macrophages from five untreated calves were harvested and treated in vitro with tilmicosin, followed by LPS stimulation. In Experiment 3, the ability of in vitro tilmicosin treatment to alter the expression of LPS-induced cyclooxygenase-2 (COX-2) mRNA was evaluated. In Experiments 4 and 5, secretory phospholipase A(2) activity was examined in untreated calves. Treatment of calves with tilmicosin resulted in reduced LPS-induced alveolar macrophage PGE(2) production. Similar reductions in PGE(2) by LPS-stimulated alveolar macrophages after in vitro tilmicosin treatment were noted. This in vitro tilmicosin treatment was not associated with reduction of the expression of LPS-induced COX-2. Alveolar macrophage phospholipase A(2) activity induced by LPS was significantly reduced by prior tilmicosin treatment in vitro. Tilmicosin (in vivo and in vitro) appears to reduce the PGE(2) eicosanoid response of LPS-stimulated alveolar macrophages by reducing the in vitro substrate availability without altering in vitro COX-2 mRNA expression.  相似文献   

8.
Infectious respiratory diseases in man and in domestic animals are characterized by the presence of a large number of different microorganisms: viruses, bacterias, mycoplasmas. It is therefore necessary to stimulate non-specific defense mechanisms in the lung and especially alveolar macrophages (AM). These cells, located in the alveolar air-spaces, play a major role in the lung clearance mechanisms and exert antibacterial, antiviral and antitumoral activities. Activation of alveolar macrophages was studied in vitro with lipopolysaccharide (LPS), lymphokines or mycobacterial derivatives (MDP). Rodent alveolar macrophages were rendered cytotoxic by in vitro exposure to LPS, free MDP or liposome-encapsulated MDP derivatives. In vivo, intravenously administered liposomes containing lipophilic MDP derivatives induced cytotoxic alveolar macrophages and protected mice against the development of pulmonary metastases.  相似文献   

9.
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10.
OBJECTIVE: To determine the amount of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) activity in alveolar macrophages in response to Actinobacillus pleuropneumoniae (APP) by determining nitric oxide (NO) and prostaglandin E2 (PGE2) concentrations. SAMPLE POPULATION: Freshly isolated porcine alveolar macrophages. PROCEDURE: Alveolar macrophages were incubated for 48 hours with APP (1 X 10(4) colony-forming units/mL), interleukin-1beta, (IL-1beta; 5 U/mL), tumor necrosis factor-alpha (TNFalpha; 500 U/mL), interferon-gamma (IFN-gamma, 100 U/mL), or lipopolysaccharide (LPS; 10 microg/mL). In a second experiment, alveolar macrophages were incubated with fresh medium (negative control), APP alone, or APP with 1 of the following: IL-1beta, TNF-alpha, or IFN-gamma. In a third experiment, alveolar macrophages were incubated with fresh medium (negative control), LPS (positive control), APP alone, or APP with 1 of the following: an iNOS inhibitor (3.3 microM), a COX-2 inhibitor (10 microM); or both the iNOS and COX-2 inhibitors. Supernatant was obtained at 0, 3, 6, 9, 12, 24, and 48 hours after treatment for determination of NO and PGE2 production. RESULTS: The addition of APP to alveolar macrophages resulted in significant increases in NO and PGE2 production. The addition of APP and IFN-gamma synergistically induced NO production. Inhibition of iNOS and COX-2 decreased NO and PGE2 production, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: In vitro activation of alveolar macrophages by APP results in increased production of NO and PGE2. Nitric oxide and PGE2 production appears to be largely dependent on iNOS and COX-2 activity. Pharmacologic modulation of iNOS and COX-2 activity may represent a therapeutic target for pigs with pleuropneumonia.  相似文献   

11.
Biological responses to recombinant DNA-derived bovine interferon alpha (rBoIFN-alpha I1) by bovine alveolar macrophages were examined by measuring viral yield reduction and 2',5'-oligoadenylate synthetase (2',5'-OAS) production by IFN-treated cells. In vitro IFN pretreatment of alveolar macrophages reduced viral yield in cultures challenged exposed with parainfluenza-3 virus, compared with control cultures. In vitro treatment of alveolar macrophages with IFN also resulted in increased 2',5'-OAS activity. The 2',5'-OAS activity was measured in alveolar macrophages and blood mononuclear leukocytes of calves injected IM with 3.6 x 10(6) U of rBoIFN-alpha I1/kg of body weight. The IFN action was monitored by measuring 2',5'-OAS activity of blood mononuclear leukocytes beginning 6 days before and ending 24 hours after IFN treatment. The 2',5'-OAS activity in the blood mononuclear leukocytes sharply increased 24 hours after IFN treatment, indicating response to IFN. The alveolar macrophages collected from the same calves 24 hours after IFN administration also had increased 2',5'-OAS activity, compared with alveolar macrophages from the same calves collected 6 days before treatment. Increased 2',5'-OAS activity indicates: a possible mechanism of IFN action in cattle that may be responsible for viral yield reduction; potential use of high enzyme activity as a marker for IFN induction; and potential use of 2',5'-OAS activity as a marker for determining effects of IFN on bovine macrophages and other cells of the bovine immune system.  相似文献   

12.
Retinoids play an important role in lung development and immune response. The effects of retinoids are mediated through 2 families of retinoid receptors: retinoic acid receptors (RARs) and retinoid X receptors (RXRs), with alpha (α), beta (β), and gamma (γ) subtypes in each family. To date, no data exist on the expression pattern of retinoid receptors in lungs of cattle, dogs, and pigs. Because of the biomedical importance of retinoid receptors in inflammation and immune responses, Western blot, immunohistology, and immunoelectron microscopy were used to determine the expression of retinoid receptors in normal lungs of cattle, dogs, and pigs (n = 2 for each species). Western blot showed expression of all 6 retinoid receptor subtypes in pig lungs. Immunohistology data indicated differential expression of retinoid receptors in airway epithelium, vascular endothelium, alveolar/septal macrophages, and alveolar septum in all 3 species. Electron microscopy showed nuclear localization of retinoid receptors in neutrophils and pulmonary intravascular macrophages. Retinoic acid receptors (RAR) α subtype were localized in cytoplasmic vacuoles of pig monocytes. These data indicate constitutive expression of retinoid receptors in the lungs of cattle, dogs, and pigs.  相似文献   

13.
Flight and avoidance reactions from human were examined using 168 postweaning Thoroughbred foals in 22 breeding farms. Further 114 yearlings of 168 foals were tested in the following summer. The foal handlings by the stabler were asked in questionnaire. The relationship between the behavioural reactions and the foal handling frequencies was analyzed. The flight reaction was estimated as the distance from the animal to a stranger when the animal began to flight away from his approach. The avoidance scores were set up from (1) (not resistant) to (5) (touch rejection) from human touching. In the stabler questionnaire, handling frequencies of “body brushing”, “rectal temperature measurement”, “hoof cleaning”, and “stall cleaning” in the early nursing period were asked. The handling frequencies were scored from (1) (not done) to (5) (every day). In the preliminary test, a measurement reliability of the flight distance and the avoidance score was confirmed. The mean flight distances were 0.56 m and 0.27 m in the postweaning foals and the yearlings, respectively. Touch-avoidance scores of the highest frequency were (3) and (2) in the postweaning foals and the yearlings, respectively. As the results of Spearman’s rank-correlation analysis, “body brushing” showed highly negative relationships with “flight distance” (ρ=–0.31, P<0.001) and “avoidance score” (ρ=–0.37, P<0.001) in the postweaning foals. In the yearlings, “hoof cleaning” also showed significantly negative relationships with these behavioural indices (ρ=–0.24, P<0.01; ρ=–0.22, P<0.01, respectively).  相似文献   

14.
The replication of porcine reproductive and respiratory syndrome virus (PRRSV) in lungs and lymphoid tissues of PRRSV-infected pigs is already strongly reduced before the appearance of neutralizing antibodies, indicating that other immune mechanisms are involved in eliminating PRRSV at those sites. This study aimed to determine whether PRRSV Lelystad virus (LV)-specific cytotoxic T-lymphocytes (CTL) can efficiently eliminate PRRSV-infected alveolar macrophages. Therefore, CTL assays were performed with PRRSV-infected alveolar macrophages as target cells and autologous peripheral blood mononuclear cells (PBMC) from PRRSV-infected pigs as a source of PRRSV-specific CTL. PBMC of 3 PRRSV-infected pigs were used either directly in CTL assays, or following restimulation in vitro. CTL assays with pseudorabies virus (PRV) Begonia-infected alveolar macrophages and autologous PBMC, from 2 PRV Begonia-inoculated pigs, were performed for validation of the assays. In freshly isolated PBMC, derived from PRRSV-infected pigs, CTL activity towards PRRSV-infected macrophages was not detected until the end of the experiment (56 days post infection – dpi). Restimulating the PBMC with PRRSV in vitro resulted in proliferation of CD3+CD8high cells starting from 14 dpi. Although CD3+CD8high cells are generally considered to be CTL, CTL activity was not detected in PRRSV-restimulated PBMC of the 3 pigs until 49 dpi. A weak PRRSV-specific CTL activity was observed only at 56 dpi in PRRSV-restimulated PBMC of one pig. In contrast, a clear CTL activity was observed in PRV Begonia-restimulated PBMC, derived from PRV Begonia-infected pigs, starting from 21 dpi. This study indicates that PBMC of PRRSV-infected pigs contain proliferating CD3+CD8high cells upon restimulation in vitro, but these PBMC fail to exert CTL activity towards PRRSV-infected alveolar macrophages.  相似文献   

15.
Blood samples were collected from the jugular vein of 87 Iranian male dromedary camels of different age groups (<3, 3–5, 5–6 and 6–8 years). Variations in the serum concentrations of cholesterol, triglyceride, total lipid, very low-density lipoprotein (VLDL-cholesterol), low-density lipoprotein (LDL-cholesterol) and high-density lipoprotein (HDL-cholesterol) were investigated. The concentrations of cholesterol, triglyceride, total lipid, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol in the different age groups were significantly different (p<0.05). With an increase in the age of the animals, there were highly significant increases in the cholesterol, triglyceride, HDL-cholesterol and VLDL-cholesterol concentrations, whereas the concentration of LDL-cholesterol decreased (p<0.001).  相似文献   

16.
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17.
Whereas in former times horses were reserved primarily for people involved in agriculture, elite equestrians or the military, nowadays equestrian sport has become an activity for people with a wide variety of backgrounds. However, as more and more people become involved with equestrian sport today, the knowledge concerning animal husbandry in general is diminishing due to an alienation from agricultural themes in modern societies. As a consequence, this development affects both riding ability and the appraisal of horses, especially with respect to the purchase of horses. In order to analyse which factors influence purchase decisions in the horse market in conjunction with equestrian experience, 739 horse riders were surveyed on their purchase behaviour in this study. Using cluster analysis, a typology was generated that provides a differentiated picture of the preferences of the various rider groups. Three clusters were distinguished: the “amateurs”, the “experienced” and the “experts”. Taking personal horse riding proficiency into account, it could be concluded that especially the “amateur” group required objective criteria for the evaluation of a horse they are considering purchasing. Alongside “measureable” qualities, such as previous showing success or the level of training of the horse, also other attributes such as the simple handling of the horse should be taken into consideration. As particularly the “amateur” group in equestrian sport is increasing in numbers, it is therefore advisable when preparing a horse for sale to align oneself to the needs of this customer segment in order to ensure an effective and targeted marketing of horses.  相似文献   

18.
The immunopharmacological activities of β-glucans with a backbone of β-1,3/β-1,6-linkages associated with anti-tumor, anti-viral, bacterial and fungal infections have been well documented. Dectin-1, a specific pattern recognition receptor for β-1,3/β-1,6-glucans, is expressed mainly on phagocytes, especially macrophages and dendritic cells (DCs). In this study, the encoding nucleotide for the carbohydrate-recognition domain (CRD) of porcine dectin-1 was sequenced for the first time, and the immunomodulatory functions of a synthetic particulate β-glucan (p-β-glucan) were examined. Results showed that p-β-glucan significantly enhanced cell activity and phagocytosis in porcine alveolar macrophages (AMs), immature DCs (imDCs) and mature DCs (mDCs), in a similar way to zymosan. Zymosan enhanced dectin-1/TLR2/TLR4 expression and TNF-α/IL-10 production in all of three types of cell, whereas p-β-glucan increased dectin-1/TLR4 and TNF-α/IL-12 production in AMs but inhibited IL-10 in mDCs. These results indicate that the complex collaborating interactions between dectin-1 and TLRs in the recognition of β-1,3/β-1,6-glucans with different structural features may direct different cellular responses.  相似文献   

19.
A five-month-old male beagle dog suddenly became moribund. Bloody fluid accumulated in the thoracic and abdominal cavities, and soft yellow flecks were floating in the thoracic fluid. The mediastinum and pericardium became dark reddish with villous thickening. Other parietal and pulmonary pleurae were rough, and the organs adhered to each other. Histologically, most mediastinal pleura formed papillary projections covered by a single layer of mesothelial cells. Many macrophages and neutrophils infiltrated the submesothelial connective tissue. At the mediastinum adjacent to the pericardium, cuboidal mesothelial cells proliferated solidly and formed a thick surface stratum. The flecks consisted of gram-negative filamentous or small bacillary (coccoid) bacteria. In the right posterior lobe of the lung, neutrophilic infiltration and a large encapsulated abscess including a bacterial colony were present. We diagnosed this case as “bacterial pleuritis with thickened mesothelial hyperplasia”. The cause of the pleuritis might be a chronic pleural infection spread via the lung abscess.  相似文献   

20.
Bovine blood lymphocytes, depleted of macrophages by absorption on plasma-gelatin coated plastic flasks, followed by passage through Sephadex G-10 columns, failed to respond to pokeweed mitogen stimulation. Adherent monocytes or alveolar macrophages added to purified lymphocyte preparations at 10% or less were able to restore the transformation response. Exposure of alveolar macrophages or purified lymphocytes to 2 bovine respiratory syncytial virus strains for 24 hours substantially reduced the transformation response when mixed with uninfected lymphocytes or macrophages. Exposure of alveolar macrophages or purified lymphocytes to 2 bovine parainfluenza type 3 virus strains produced a similar reduction in activity after 48 hours. Heat inactivation of the viruses removed their inhibitory ability. Immunofluorescence studies revealed that both alveolar macrophages and lymphocytes were permissive for parainfluenza type 3 virus, whereas only a small number of alveolar macrophages and lymphocytes were infected with respiratory syncytial virus. The results suggest that both viruses are capable of adversely affecting the interaction between macrophages and lymphocytes, although the mechanisms by which this is achieved may be different.  相似文献   

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