共查询到20条相似文献，搜索用时 31 毫秒
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Walravens K Wellemans V Weynants V Boelaert F deBergeyck V Letesson JJ Huygen K Godfroid J 《Veterinary immunology and immunopathology》2002,84(1-2):29-41
Three 10 months old cattle were infected by the intratracheal route with 10(6)cfu of a field strain of Mycobacterium bovis. Blood samples were regularly collected for in vitro IFN-gamma production after antigenic stimulation. Peripheral blood cells of infected animals produced IFN-gamma in response to crude M. bovis antigens (live and heat-inactivated BCG and protein-purified derivative (PPD)) 3-4 weeks after infection. The ratio of the response to bovine PPD versus avian PPD indicated a specific sensitisation for M. bovis antigens. Three months post-infection (PI), animals were culled and M. bovis was cultured from tubercle lesions. At different time points, the frequency of specific M. bovis IFN-gamma producing CD4+, CD8+ and WC1+ T-cells in the peripheral blood was examined by flow cytometry. Two colour immunofluorescence staining of intracellular IFN-gamma and bovine cell surface molecules showed that both CD4+ and CD8+, but not WC1+, T-cells produced IFN-gamma following stimulation with PPD, live or killed BCG.In two animals analysed, the relative percentage of circulating IFN-gamma producing CD8+ cells decreased between week 5 and week 9 PI. The same evolution was not observed for IFN-gamma secreting CD4+ cells. Magnetic positive selection of T-cells from infected animals showed that CD4+ T-cells produced specific IFN-gamma only in the presence of antigen presenting cells (APCs). Positively selected CD8+ T-cells secreted IFN-gamma only in the presence of recombinant human IL-2 and APCs. In vitro depletion of the CD4+ T-cells, but not the depletion of CD8+ or WC1+ T-cells, resulted in abrogation of the specific IFN-gamma production showing the key role of this cell population for the specific IFN-gamma production. 相似文献
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A El Naas M Levkut V Revajová M Levkutová V Hipíková V Letková 《Veterinary parasitology》1999,82(2):137-143
The study was performed to determine the immune response to Encephalitozoon cuniculi infection in immunocompetent mice during 120 days of experiment. Mice infected with E. cuniculi had an increased number of CD4+ T cells up to Day 20 post infection (p.i.), but counts of CD8+ T lymphocytes were significantly lower up to Day 90 p.i. in peripheral blood. Blood monocytes were significantly increased on the Day 60 and Day 120 of infection. A lack of significant decrease of CD4+ T cells may be considered as an important event in the immune response to E. cuniculi infection in immunocompetent mice. 相似文献
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Tanaka S Aso H Miyazawa K Nagai Y Watanabe K Ohwada S Kobayashi J Yamaguchi T 《Veterinary immunology and immunopathology》2007,118(1-2):84-91
The distinct patterns of cytokine expression in CD4+ and CD8+ T cells are well understood in mice and humans. However, little information is available about cytokine expression in bovine CD4+ and CD8+ T cells. In this study, mRNA expression of 19 different cytokines was analyzed in CD4+ and CD8+ T cells of calves with or without Concanavalin A (Con A) stimulation. CD4+ and CD8+ T cell populations were enriched to 98% purity by positive selection using magnetic cell sorting (MACS). CD4+ T cells spontaneously expressed the mRNAs of interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-6, IL-7, IL-8, IL-10, IL-18, IFN-gamma, TNF-alpha, TNF-beta and TGF-beta, and augmented the mRNA expression of IL-10, IFN-gamma and TNF-beta after Con A stimulation. The mRNAs of IL-3, IL-4, IL-5, IL-13 and GM-CSF were newly expressed in Con A-stimulated CD4+ T cells. CD8+ T cells displayed spontaneous mRNA expression of IL-6, IL-18, TNF-alpha, TNF-beta and TGF-beta, and newly expressed the mRNA of IL-2, IL-7, interferon-gamma (IFN-gamma) and GM-CSF after Con A stimulation. It was found that CD4+ T cells expressed the mRNA of 17 cytokines except for IL-12 and IL-15, while CD8+ T cells expressed only the mRNA of 9 cytokines after Con A stimulation. The profile of cytokine mRNA expression was substantially different in the CD4+ and CD8+ T cells of calves, indicating that CD4+ T cells can be distinguished from CD8+ T cells by the cytokine gene expression of IL-1alpha, IL-1beta, IL-3, IL-4, IL-5, IL-8, IL-10 and IL-13. Differential cytokine expression between CD4+ and CD8+ T cells serve to interpret an individual function of T cell subsets in the immune system of calves. 相似文献
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Wyatt CR Barrett WJ Brackett EJ Davis WC Besser TE 《Veterinary immunology and immunopathology》1999,67(3):213-222
Ileal intraepithelial lymphocyte (IEL) suspensions from suckling calves (1-3 weeks old) and weaned calves (3-6 months old) were phenotyped to determine whether there were differences in the lymphocyte populations consistent with postnatal maturation of the mucosal immune system. Flow cytometric comparisons of IEL from the two age groups revealed the presence of significantly larger proportions of CD4+ T lymphocytes and CD8+ T cells in the weaned animals. In contrast, there was a significantly larger proportion of B-B2+ IEL in the suckling calves. Freshly isolated IEL from both groups of calves expressed mRNA for TNF-alpha and IFN-gamma, but not IL-4 or IL-10. The B-B2+ IEL population was more closely examined by flow cytometry. These cells co-expressed IgM and CD21. However, they did not express IgA, IgG1, nor any of several additional leukocyte differentiation molecules. Immunohistochemical data confirmed the presence of IgM+ lymphocytes, and the paucity of IgA+ and IgG1+ lymphocytes in suckling calf ileum. However, substantial numbers of IgA+ and IgG1+ cells were observed in weaned calf ileum. Together, the data are consistent with ongoing postnatal maturation of the gut mucosal immune system. 相似文献
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Judith R Stabel Kayoko Kimura Suelee Robbe-Austerman 《Journal of veterinary diagnostic investigation》2007,19(1):43-51
Measurement of secreted interferon (IFN)-gamma has proven to be a valuable tool for the detection of animals infected with mycobacterial pathogens, including Mycobacterium avium subsp. paratuberculosis. Previous reports have suggested that tuberculin skin testing can influence the performance of the IFN-gamma assay. In the present study, healthy noninfected cows, and cows subclinically and clinically infected with M. paratuberculosis were administered an intradermal injection of johnin purified protein derivative (JPPD) and effects on secreted and intracellular IFN-gamma were observed. Intradermal injection resulted in significant increases in secreted IFN-gamma for subclinically infected cows after stimulation of peripheral blood mononuclear cells (PBMC) with concanavalin A or M. paratuberculosis antigen preparations (whole-cell sonicate and JPPD) on days 7 and 10 postinjection. Intracellular IFN-gamma was increased after intradermal injection in total PBMC for all treatment groups and was higher within CD4+ and CD8+ subpopulations for infected cows compared to healthy controls throughout the study. When T-cell populations were further defined by CD45RO expression, intracellular IFN-gamma was higher within CD8+/CD45RO+ lymphocytes compared to CD4+/CD45RO+ cells for subclinically and clinically infected cows but similar within these subpopulations for healthy controls. These results indicate that intradermal sensitization of cows in the subclinical stage of infection will upregulate expression of IFN-gamma, enhancing the sensitivity of this assay. In addition, CD8+ lymphocytes appear to play an important role as a mediator of M. paratuberculosis infection in naturally exposed cattle. 相似文献
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Lymphocyte subset proliferative responses of Mycobacterium bovis-infected cattle to purified protein derivative 总被引：2，自引：0，他引：2
Waters WR Palmer MV Pesch BA Olsen SC Wannemuehler MJ Whipple DL 《Veterinary immunology and immunopathology》2000,77(3-4):257-273
Despite highly successful eradication efforts in several countries, Mycobacterium bovis infection of cattle remains a significant health concern worldwide. Immune mechanisms of resistance to and/or clearance of M. bovis infection of cattle, however, are unclear. Recent studies have provided evidence supporting a role for CD4(+), CD8(+), and gammadelta TCR(+) T cells in the response of cattle to M. bovis. In the present study, we utilized a flow cytometric-based proliferation assay to determine the relative contribution of individual lymphocyte subsets in the response to M. bovis infection and/or sensitization with mycobacterial purified protein derivative (PPD). Peripheral blood mononuclear cells (PBMC) from M. bovis-infected cattle proliferated in response to in vitro stimulation with M. bovis PPD. CD4(+) T cells and gammadelta TCR(+) cells were the predominate subsets of lymphocytes responding to PPD. gammadelta TCR(+) cells also proliferated in non-stimulated cultures; however, the gammadelta TCR(+) cell proliferative response of infected cattle was significantly (p<0.05) greater in PPD-stimulated cultures as compared to non-stimulated cultures. Intradermal injection of PPD for comparative cervical testing (CCT) induced a boost in the in vitro proliferative response of CD4(+) but not gammadelta TCR(+) cells of infected cattle. Administration of PPD for CCT also boosted interferon-gamma (IFN-gamma) production by PBMC of infected cattle following in vitro stimulation with M. bovis PPD. Injection of PPD for CCT did not, however, elicit a proliferative or IFN-gamma response in cells isolated from non-infected cattle. These data indicate that CD4(+) and gammadelta TCR(+) cells of M. bovis-infected cattle proliferate in a recall response to M. bovis PPD and that the CD4(+) cell response is boosted by intradermal injection with PPD for CCT. 相似文献
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Characterization of monoclonal antibodies to equine interleukin-10 and detection of T regulatory 1 cells in horses 总被引：1，自引：1，他引：0
Wagner B Hillegas JM Brinker DR Horohov DW Antczak DF 《Veterinary immunology and immunopathology》2008,122(1-2):57-64
Interleukin-10 (IL-10) terminates inflammatory immune responses and inhibits activation and effector functions of T-cells, monocytes, macrophages and dendritic cells. IL-10 has also been found to be a key cytokine expressed by subpopulations of regulatory T-cells. In this report, we describe the generation and characterization of three monoclonal antibodies (mAbs) to equine IL-10. The antibodies were found to be specific for equine IL-10 using different recombinant equine cytokine/IgG fusion proteins. Two of the anti-equine IL-10 mAbs were selected for ELISA to detect secreted IL-10 in supernatants of mitogen stimulated equine peripheral blood mononuclear cells (PBMC). The sensitivity of the ELISA for detecting secreted IL-10 was found to be around 200pg/ml. The production of intracellular IL-10 was measured in equine PBMC by flow cytometry. PBMC were stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin in the presence of the secretion blocker Brefeldin A. All three anti-IL-10 mAbs detected a positive population in PMA stimulated lymphocytes which was absent in the medium controls. Around 80% of the IL-10(+) cells were CD4(+). Another 15% were CD8(+) cells. Double staining with IL-4 or interferon-gamma (IFN-gamma) indicated that PMA and ionomycin stimulation induced 80% IL-10(+)/IFN-gamma(+) lymphocytes, while only 5% IL-10(+)/IL-4(+) cells were observed. By calculation, at least 60% of the IL-10(+)/IFN-gamma(+) cells were CD4(+) lymphocytes. This expression profile corresponds to the recently described T regulatory 1 (T(R)1) cell phenotype. In summary, the new mAbs to equine IL-10 detected native equine IL-10 by ELISA and flow cytometry and can be used for further characterization of this important regulatory cytokine in horses. 相似文献
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W R Waters R E Sacco A D Dorn R Hontecillas F A Zuckermann M J Wannemuehler 《Veterinary immunology and immunopathology》1999,69(1):75-87
Serpulina hyodysenteriae infection of pigs, swine dysentery, causes a mucohemorrhagic diarrhoea resulting in significant economic losses to swine producers. The pathogenesis of this disease is poorly understood. Regardless, commercial vaccines have been developed and are in use. Thus, the present study was designed to examine cellular immune responses induced by parenteral S. hyodysenteriae vaccination. Significant antigen-specific interferon-gamma (IFN-gamma) and blastogenic responses were detected from peripheral blood lymphocytes isolated from vaccinated pigs. However, poor IFN-gamma responses were detected from colonic lymph node lymphocytes from these same pigs despite significant antigen-specific blastogenic responses. In addition, peripheral blood IFN-gamma responses were diminished by either in vitro depletion of CD4 expressing cells or by in vitro treatment with porcine IL-10. Colonic lymph node IFN-gamma responses were not inhibited by treatment with porcine IL-10. Vaccination also resulted in increased percentages of both mucosal and peripheral blood CD8 single positive cells with concurrent decreases in percentages of CD4 single positive cells as compared to percentages of these same populations from non-vaccinated pigs. In conclusion, these studies show that parenteral S. hyodysenteriae vaccination results in cellular immune responses detectable both peripherally (systemic immunity) as well as at the site of infection (mucosal immunity). However, it appears that regulatory mechanisms affecting IFN-gamma production in response to S. hyodysenteriae antigen differ between peripheral and colonic compartments. 相似文献
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To better understand the interaction between Mycoplasma bovis and its bovine host, we have characterized the immune response generated during an experimental lung infection with M. bovis. Proliferation ([3H]-thymidine blastogenesis) and Th1/Th2 cytokine production were used to monitor peripheral cellular immune responses. Flow cytometry analysis was used to determine T-cell subset activity by CD25 expression. Humoral immune response was monitored by the identification of antigen-specific IgG1 and IgG2 isotypes over time. Herein, we show that M. bovis antigen stimulates activation of CD4+ and CD8+ cells in vitro in a manner consistent with memory, and that gammadelta-T cells are activated by antigen in a manner consistent with innate immunity. In addition, the percentage of cells producing IFN-gamma during recall response is equal to that of IL-4 producing cells. Serological analysis shows M. bovis stimulates increased production of antigen-specific IgG1 while very little IgG2 is produced. We therefore submit that experimental lung infection of cattle with M. bovis results in a Th2-skewed immune response. 相似文献
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Esteves I Walravens K Vachiéry N Martinez D Letesson JJ Totté P 《Veterinary immunology and immunopathology》2004,98(1-2):49-57
Interferon gamma (IFN-gamma) is considered as a key mediator of protective cell-mediated immunity against intracellular pathogens in general, and against Ehrlichia ruminantium, the causative agent of tick-borne heartwater disease of ruminants, in particular. However, the source of this important cytokine in animals immunized against E. ruminantium remains largely unknown. We have analyzed in goats protected by vaccination with a killed E. ruminantium vaccine, the potential of individual, genuine (i.e., non-cloned), T cell subsets to produce IFN-gamma after antigenic recall in vitro. In all vaccinated but none control animals, E. ruminantium-induced IFN-gamma secretion was observed in 24 h stimulated blood. Flow cytometric analysis of stimulated peripheral blood mononuclear cells (PBMCs) collected after each vaccine inoculation indicated that immune CD4+ and CD8+ T cells contribute to the same extent to the production of IFN-gamma, while WC1+ T cells are less important. This was confirmed by blocking the secretion of IFN-gamma with anti-classes I and II major histocompatibility complex antibodies. Blocking experiments also suggest that CD8+ need the help of CD4+ T cells in order to produce IFN-gamma. Thus, this work underlines the key role of CD4+ T cells in the production of IFN-gamma by immune goat PBMC. It also describes, for the first time in ruminants, E. ruminantium-specific CD8+ effector T cells. Since CD4+ and CD8+ T cells collectively contribute to the production of IFN-gamma in most vaccinated animals, and since these responses are associated with protection, it may be that a recombinant vaccine will need to incorporate E. ruminantium antigens capable of driving both responses. 相似文献
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通过检测奶牛C D3+、CD4+和CD8+淋巴细胞亚群的动态及细胞因子IL-2、IL-4在分娩前后21d内的基因转录水平的变化,以探讨此阶段奶牛免疫机能受损的机理.应用流式细胞术检测CD3+、CD4+、CD8+淋巴细胞亚群的动态变化及实时荧光定量检测细胞因子IL-2、IL-4 mRNA的表达量.结果表明:血液中CD3+淋巴细胞的比例在产前21 d内占(50.8±4.61)％,产后14 d内降低到(39.21±4.98)％,两者差异极显著(P＜0.01) ;CD4+淋巴细胞在产前21 d内保持较高水平,达(21.38±0.65)％,产后21 d内维持在(6.89±0.32)％的较低水平,且与产前差异显著(P＜0.05) ;CD8+淋巴细胞的比例在产犊前逐渐升高,到产犊时达到最高水平(16.90±2.02)％,差异显著(P＜0.05) ;CD4+/CD8+淋巴细胞的比率在产前＞1,产后＜1.IL-2 mRNA的表达量在产后0～14 d内下调,之后上升.IL-4 mRNA的表达量分娩时期达到最高,随后下降,至第7天降到最低.奶牛在围产期阶段尤其是分娩前后14 d内机体处于免疫抑制状态,可能是由于自身的CD3+、CD4+和CD8+T淋巴细胞的亚群的数量和比例发生改变及细胞因子IL-2、IL-4 mRNA表达量下调引起的. 相似文献
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Breathnach CC Soboll G Suresh M Lunn DP 《Veterinary immunology and immunopathology》2005,103(3-4):207-215
A commercial bovine IFN-gamma-specific monoclonal antibody was used to measure antigen-specific IFN-gamma production by equine lymphocytes. Paired PBMC samples were collected from six ponies prior to and 10 days after challenge infection with equine herpesvirus-1 (EHV-1). Each sample was stimulated in vitro with EHV-1, virus-free medium, or PMA and ionomycin, and labelled with monoclonal antibodies specific for various equine lymphocyte subset markers. Following fixation, intracellular IFN-gamma was detected using a FITC-conjugated bovine IFN-gamma-specific monoclonal antibody. In vitro restimulation of PBMC with EHV-1 induced IFN-gamma production by a significantly higher percentage of total (CD5(+)) T lymphocytes, and CD4(+) and CD8(+) T lymphocyte subsets among post-EHV-1 infection PBMC samples compared to pre-infection samples. This response was associated with an increase in virus-specific CTL activity, a critical immune effector for the control of EHV-1 infection and disease. No significant increase in IFN-gamma production by B lymphocytes was observed. These data demonstrate that EHV-1 challenge infection of ponies results in increased production of IFN-gamma by virus-specific T lymphocytes, and that this response can be quantitated using flow cytometry. 相似文献
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S. Frink B. Grummer J. F. Pohlenz E. M. Liebler‐Tenorio 《Zoonoses and public health》2002,49(10):476-483
Mucosal disease (MD), one sequelae of bovine virus diarrhoea virus (BVDV) infection, causes severe lesions in lymphoid tissues and mucosal surfaces. Lesions are associated with the presence of cytopathogenic (cp) BVDV and initially characterized by apoptotic cell death. The objective of this investigation was to determine if this cell death is mediated only by the cp BVDV, which is known to induce apoptosis in cell culture or if immune‐mediated host reactions might also contribute. Early onset MD was experimentally induced in calves by inoculation of persistently viremic calves with a closely related cp BVDV. Calves were euthanized in the early phase of infection between days 5 and 13 post‐inoculation and tissues from tonsils, lymph nodes, Peyer's patches, jejunum and colon were collected. Presence of cp BVDV antigen was correlated with distribution of lymphocyte subpopulations in consecutive cryostat sections. In the lymphoid tissues, cp BVDV antigen was predominantly found in the lymphoid follicles. The increase of infected cells with time post‐inoculation was paralleled by a decrease of B‐lymphocytes and an increase of CD4+ T‐lymphocytes. An increased number of CD8+ T‐lymphocytes was seen in progressed lesions only. In the intestinal mucosa, initially multifocal, later diffuse infection with cp BVDV was accompanied by a multifocal or diffuse increase of CD4+ T‐lymphocytes, respectively. Numbers of IgA+ plasma cells and CD8+ T‐lymphocytes were decreased. The common change observed in lymphoid tissues and mucosa was the increase of CD4+ T‐lymphocytes in sites with lesions. This might indicate a cell‐mediated immune response to the cp BVDV. Besides their helper function to other cells of the immune system, activated CD4+ T‐lymphocytes might also exert cytotoxic activity, induce apoptosis in target cells via Fas/Fas ligand binding and thus contribute to the severity of tissue lesions in MD. 相似文献
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McBride JW Corstvet RE Taylor BC Osburn BI 《Veterinary immunology and immunopathology》1999,67(2):161-170
Site-specific responses of bronchoalveolar and peripheral blood lymphocyte subsets were compared during primary and anamnestic immune responses against live Pasteurella haemolytica A1 (Ph1). Eight 1-year old calves were sequentially exposed intrabronchially with aerosolized Ph1 on days 0, 14, and 21, and two calves were sham exposed. Bronchoalveolar and peripheral blood lymphocytes were analyzed before each Ph1 exposure, and on days 3 and 7 post exposure using single and two-color flow cytometry to identify CD2+, CD4+, CD8+, CD21+, CD45R+, CD25+ and gammadelta lymphocyte subsets. Significant differences (p < 0.05) in bronchoalveolar and peripheral blood lymphocyte subsets were observed before Ph1 exposure. Subsequent aerosol exposures, resulted in significant (p < 0.05) changes in bronchoalveolar lymphocyte subsets and the CD4:CD8 bronchoalveolar lymphocyte ratio, but concomitant changes were not observed in peripheral blood lymphocytes. Expression of CD2, CD4 and CD8 lymphocyte differentiation antigens was consistently lower and more heterogeneous on bronchoalveolar lymphocytes. Differential analysis of bronchoalveolar leukocytes revealed a significant increase in bronchoalveolar lymphocytes and neutrophils during anamnestic responses. 相似文献