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51.
Plasmid vaccine pBK-CMVMP1LC113 expressing the matrix (M) gene of rinderpest virus was assessed for its potential to protect rabbits against a lethal viral challenge. Rabbits immunized with plasmids expressing the M gene were not protected when challenged with lapinized rinderpest virus, despite the production of anti-M antibodies, while rabbits immunized with rinderpest tissue culture vaccine were completely protected from a lethal challenge with lapinized rinderpest virus. The plasmid vaccine also had no significant effect on the lymphopenia in challenged rabbits. The results indicate that rinderpest M protein does not have a protective role in rinderpest infection.  相似文献   
52.
East Coast fever, an acute lymphoproliferative disease of cattle, is caused by the apicomplexan parasite Theileria parva. Protective immunity is mediated by CD8(+) cytotoxic T lymphocytes directed against schizont-infected cells. The polymorphic immunodominant molecule, although an antibody-inducing surface molecule of the schizont, has been hypothesized to play a role in protective immunity. In order to evaluate the immunogenicity of PIM for inducing CTL, cattle were immunized with PIM in isolation from other T. parva antigens, forcing the presentation of PIM-derived epitopes on the MHC class I molecules. Although parasite-specific cytotoxicity was induced in both vaccinated animals, their immune response was clearly different. One animal generated MHC-restricted parasite-specific CTL against PIM while the other calf exhibited a strong PIM-specific proliferative response but non-MHC-restricted parasite-specific cytotoxicity. Only calf 1 survived a lethal sporozoite challenge. This DNA immunization technique with an antigen in isolation of CTL-immunodominant antigens might open possibilities for directing CTL responses against predefined antigens, such as strain cross-reacting CTL antigens.  相似文献   
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54.
本试验首次以体外培养的小鼠胸腺淋巴细胞为实验对象,加入旋毛虫(Trichinella spiralis)肌幼虫ES抗原做刺激物,通过对鼠胸腺淋巴细胞DNA损伤、凋亡水平的检测,进而证明旋毛虫肌幼虫ES抗原能够诱导鼠胸腺淋巴细胞发生调亡。掌握这种免疫细胞凋亡(apoptosis)发生的过程,对分析免疫应答的特点和调控,以及探索旋毛虫病(Trichinosis)的发病机制和提供防治对策都具有重要意义。  相似文献   
55.
Monoclonal antibodies provide powerful tools for detection of lineage-specific markers on hematopoietic cells. We used the combination of cell morphology, cytochemistry, flow cytometric scatter plot analysis, and labeling of cells with 6 monoclonal antibodies to detect and subclassify lymphocytic leukemia in bone marrow from 5 dogs. Antibodies included anti-CD18 (a panleukocyte marker), anti-MHC class II (detects most B and T lymphocytes and monocyte/macrophages), anti-Thy-1 (a pan-T-lymphocyte and monocyte/macrophage marker), anti-CD3 (a pan-T-lymphocyte marker), anti-CD21 (a B-lymphocyte marker), and anti-CD14 (a monocyte/macrophage marker). Of the 5 dogs evaluated, 2 were categorized as acute T-cell prolymphocytic leukemia, 2 as acute non-T, non-B lymphoblastic leukemia, and 1 as acute B-cell lymphoblastic leukemia. Results of this study indicate marked variation in the morphology and immunophenotype of canine lymphocytic leukemia.  相似文献   
56.
HBV转基因小鼠T细胞免疫状态   总被引:2,自引:0,他引:2  
以正常非转基因 ICR小鼠为对照 ,用 3H-Td R掺入法和 ELISA分别测定了 HBV转基因 ICR小鼠脾淋巴细胞针对 HBe Ag的特异性增殖功能及其培养液上清中 Th1、Th2相关细胞因子 m IFN-γ、m IL-2、m IL-6、m IL-1 0含量。结果 ,HBV转基因小鼠脾淋巴细胞对 HBe Ag刺激引起的增殖反应、HBe Ag与 Con A共同刺激引起的增殖反应及其培养液上清中 4种细胞因子含量均明显低于对照组。以上结果表明 ,HBV转基因小鼠 Th1、Th2淋巴细胞所介导的特异性免疫功能均受到抑制  相似文献   
57.
犬淋巴细胞转化增殖试验最佳条件的确定   总被引:2,自引:1,他引:1  
本试验选择杂种牧羊犬作为实验犬,用MTT法检探讨了不同浓度犊牛血清(FCS)、淋巴细胞、植物血凝素P(PHA-P)和刀豆蛋白A(ConA)对犬淋巴细胞增殖的影响。确定了犊牛血清含量为10%,淋巴细胞浓度为5×106个/mL,用丝裂原PHA-P 刺激的最佳浓度为12.5ug/mL时,MTT法测定能够刺激犬淋巴细胞转化增殖,但t检验分析表明其促进淋巴细胞增殖的效果并不显著;当其它条件不变,所用的丝裂原为Con A时,它在浓度为0.5~2.5μg/mL范围内均可以显著刺激T细胞的增殖(P<0.05),且在浓度为2.5μg/mL时刺激效果最佳  相似文献   
58.
This experiment was aimed to compare the effects of different mulberry leaf extract on spleen lymphocyte proliferation in mice. Mulberry leaf polysaccharides (MLP-1, MLP-2, MLP-3, MLP-4 and MLP-5) were prepared with mulberry leaf aqueous extract (MLAE) by different concentration of alcohol deposit, polysaccharides concentration of all extracts were determined by phenol sulfuric acid method. Five different MLPs and MLAE were as the experimental drug, when polysaccharide concentration was 15.625, 31.25, 62.5, 125 and 250 μg/mL, the changes of spleen B and T lymphocytes proliferation in mice which were stimulated by MLPs and MLAE in single or synergistical stimulation of drugs with LPS and PHA were determined by MTT method. The results showed that when polysaccharide concentration was in the range of 15.625 to 250 μg/mL, MLPs and MLAE in single or synergistical stimulation with LPS and PHA could stimulate the spleen B and T lymphocytes proliferation, MLP-1 at low concentration could stimulate significantly spleen B lymphocyte proliferation remarkably (P<0.05), and MLP-3 and MLP-5 at low concentrations showed strong stimulation ability of T lymphocyte proliferation. When MLAE was in synergistical stimulation with LPS at most concentrations points, the spleen B lymphocytes proliferation in mice were significantly higher than those of the cell control and LPS control groups, which revealed that MLAE could significantly improve the humoral immune function (P<0.05).  相似文献   
59.
The present study examined the influence of leucine metabolite β‐hydroxy‐β‐methylbutyrate (HMB), a natural product HMB, on nonspecific cell‐mediated defence mechanisms and protection against enteric redmouth disease (ERM) in pikeperch (Sander lucioperca). β‐hydroxy‐β‐methylbutyrate was fed in a pelletted ration at 50 mg kg?1 of the feed for 8 weeks. The phagocytic ability and potential killing activity of blood and pronephric phagocytes were examined in HMB‐ and control‐fed fish before and after 8 weeks of feeding HMB. Simultaneously, the proliferative response of blood and pronephric lymphocytes stimulated by mitogens concanavaline A and lipopolisaccharide were examined in experimental and control groups. Following 8 weeks of HMB feeding, a challenge test was performed by injecting the fish with live pathogenic bacteria Yersinia ruckeri. β‐hydroxy‐β‐methylbutyrate applied in the diet for 8 weeks prompted a statistically significant (P<0.05) increase in phagocytic ability and potential killing activity of the blood and pronephric phagocytes and the proliferative response of blood and pronephric lymphocytes. The changes in these mechanisms correlated with protection against Y. ruckeri, the ERM pathogen. The results showed that feeding HMB increased the nonspecific cell‐mediated defence mechanisms and protection against ERM by reducing cumulative mortality (30%) following the challenge with pathogenic bacteria. Future studies will include determination of optimal doses and protocols of oral application of HMB to maximize the immunomodulatory effects and protection against viral diseases in intensive pikeperch culture.  相似文献   
60.
借鉴哺乳动物内皮细胞体外培养技术,结合鱼类细胞自身特点,纯化培养鲤血管内皮细胞并传至3代,以此作为粘附材料。应用淋巴细胞分离液离心技术并结合玻璃粘附法分离纯化鲫、草鱼外周血中淋巴细胞、单核细胞,并与上述3代内皮细胞进行免疫粘附试验,同时进行免疫粘附动力学观察。结果显示,鲫、草鱼两类细胞对内皮细胞的粘附率分别为0.09±0.013,0.20±0.018;0.11±0.015,0.21±0.023。表明鲤科鱼类不同种的同类细胞粘附率差异不大,而同种不同类细胞则差异显著。动力学观察分析表明,淋巴细胞粘附较快,60min进入平台期;单核细胞粘附慢,120min进入平台期。初步证明鱼类内皮细胞具有免疫介导作用。  相似文献   
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