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131.
Jared R. Patch Pervaiz A. Dar Ryan Waters Felix N. Toka Jose Barrera Christopher Schutta Ganesh Kondabattula William T. Golde 《Comparative immunology, microbiology and infectious diseases》2014
Natural killer (NK) cells play a role in innate antiviral immunity by directly lysing virus-infected cells and producing antiviral cytokines such as interferon gamma (IFN-γ). We developed a system for characterizing the bovine NK response to foot-and-mouth disease virus (FMDV), which causes a disease of cloven-hoofed animals and remains a threat to livestock industries throughout the world. IL-2 stimulation of PBMC resulted in poor killing of human K562 cells, which are often used as NK target cells, while lysis of the bovine BL3.1 cell line was readily detected. Depletion of NKp46-expressing cells revealed that 80% of the killing induced by IL-2 could be attributed to NKp46+ cells. In order to characterize the response of NK cells against FMDV in vivo, we infected groups of cattle with three different strains of the virus (A24 Cruzeiro, O1 Manisa, O Hong Kong) and evaluated the cytolytic ability of NK cells through the course of infection. We consistently observed a transient increase in cytolysis, although there was variation in magnitude and kinetics. This increase in cytolysis remained when CD3+ cells were removed from the preparation of lymphocytes, indicating that cytolysis was independent of MHC-T cell receptor interaction or γδ T cell activation. In contrast, animals monitored following vaccination against FMDV did not exhibit any increase in NK killing. These data suggest that NK cells play a role in the host immune response of cattle against FMDV, and contrast with the suppression of NK activity previously observed in swine infected with FMDV. 相似文献
132.
Usefulness of the murine model to study the immune response against Histoplasma capsulatum infection
Jorge H. Sahaza Armando Pérez-Torres Edgar Zenteno Maria Lucia Taylor 《Comparative immunology, microbiology and infectious diseases》2014
The present paper is an overview of the primary events that are associated with the histoplasmosis immune response in the murine model. Valuable data that have been recorded in the scientific literature have contributed to an improved understanding of the clinical course of this systemic mycosis, which is caused by the dimorphic fungus Histoplasma capsulatum. Data must be analyzed carefully, given that misinterpretation could be generated because most of the available information is based on experimental host–parasite interactions that used inappropriate proceedings, i.e., the non-natural route of infection with the parasitic and virulent fungal yeast-phase, which is not the usual infective phase of the etiological agent of this mycosis. 相似文献
133.
以断奶仔猪为试验对象,探讨海滨锦葵块根粉和酶制剂对断奶仔猪生长和免疫的影响。64头28日龄断奶仔猪随机分为4组,对照组饲喂基础日粮,试验I、Ⅱ、Ⅲ组分别饲喂基础日粮添加0.02%复合酶制剂、0.50%和1.00%海滨锦葵块根粉。试验期28d。结果表明,酶制荆和海滨锦葵块根粉对断奶仔猪的日采食量和日增重有提高趋势,但差异不显著(P〉0.05);与对照组相比,酶制剂和海滨锦葵块根粉对断奶仔猪血清中溶菌酶活性无显著影响(P〉0.05);有降低血清中TNF-Ⅱ含量的趋势,但差异不显著(P〉0.05);与对照组相比,酶制剂可以显著降低IL-6含量(P〈0.05),海滨锦葵块根粉也降低了IL6含量,但差异不显著(P〉0.05);与对照组相比,酶制剂组、0.50%和1.00%的海滨锦葵块根粉组的猪瘟疫苗抗体效价分别提高了15.27%(P〉0.05)、18.18%(P〉0.05)和5I.64%(P〈0.05)。结果提示,酶制剂与海滨锦葵块根粉对断奶仔猪生长性能有提高趋势,同时也可以提高断奶仔猪的机体免疫力。 相似文献
134.
黄芪多糖对猪瘟活疫苗免疫应答的佐剂作用 总被引:2,自引:0,他引:2
为研究黄芪多糖对猪瘟活疫苗的佐剂作用,分别用0.5%黄芪多糖、疫苗专用稀释液、生理盐水(对照)稀释猪瘟耐热保护剂活疫苗免疫猪,测定免疫后不同时间段内血清中 IgG 及其亚型IgG1、IgG2、IgG3、IgG4和细胞因子IL 2、IL 6的含量。结果显示,与对照组相比,黄芪多糖作为疫苗稀释液可以显著提高血清中IgG及其亚型和细胞因子IL 2、IL 6的含量。与疫苗专用稀释液组相比,在免疫后第7、14、28天,黄芪多糖组IgG含量均提高,分别提高1.6%(P>0.05)、6.4%(P<0.05)、7.1%(P<0.05),IL 2含量分别提高12.1%(P<0.05)、2.9%(P>0.05)、15.3%(P<0.05),IL 6含量差异均不显著。表明,黄芪多糖作为疫苗稀释液对猪瘟活疫苗具有良好的佐剂作用。 相似文献
135.
用生长和非特异性免疫力评定异育银鲫维生素C需要量 总被引:22,自引:1,他引:22
用维生素 C(Vc)含量为0~1200mg·kg~(-1)的精制饲料,连续投喂异育银鲫8周后,测定异育银鲫生长速度和非特异性免疫指标。结果表明,在饲料Vc含量达150mg·kg~(-1)时日增重率最大,进一步提高饲料Vc含量,日增重率没有显著变化;饲料Vc含量为75mg·kg~(-1)时头肾指数显著提高,而脾指数不受饲料Vc含量的影响;头肾细胞吞噬活性和A花环率均在Vc含量为300mg·kg~(-1)时达最高水平;而血清溶菌酶活性和总补体活性分别在饲料Vc为300mg·kg~(-1)和600mg·kg~(-1)时达最高值。上述结果表明饲料Vc可显著提高异育银鲫免疫力。鉴于Vc的免疫促进作用,建议在疾病多发季节饲料Vc添加量提高到300mg·kg~(-1)。 相似文献
136.
Andrzej K Siwicki Zdzisaw Zak John C Fuller Jr Steven Nissen Sylwia Trapkowska Edward Gbski Agata Kowalska Krzytof Kazu & Elbieta Terech-Majewska 《Aquaculture Research》2006,37(2):127-131
Studies have shown that in both in vitro and in vivo tests, β‐hydroxy‐β‐methylbutyrate (HMB) increases the nonspecific cellular and humoral immune response and protection against diseases in animals. The present study examines the influence of HMB on nonspecific humoral defense mechanisms and protection against furunculosis in pikeperch (Sander lucioperca). β‐hydroxy‐β‐methylbutyrate was fed in a pelleted ration of 50 mg kg?1 feed day?1 for 4 weeks. Blood was drawn from 12 HMB‐fed and control‐fed pikeperch. The lysozyme and ceruloplasmin activities in the plasma, total immunoglobulin (Ig) levels, and total serum protein were analysed prior to and then after 2 and 4 weeks of HMB ingestion. After 4 weeks of HMB ingestion, a challenge test was performed by injecting the fish with live pathogenic Aeromonas salmonicida bacteria. β‐hydroxy‐β‐methylbutyrate at a dose of 50 mg kg?1 feed resulted in a statistically significant (P<0.05) increase in the lysozyme activity of the plasma, total Ig, and serum protein levels. Additionally, reduced mortality (40%) after the in vivo challenge with pathogenic A. salmonicida suggested that HMB‐activated nonspecific protection against furunculosis in pikeperch. 相似文献
137.
138.
凡纳滨对虾在微囊藻毒素(MC-LR)诱导下3种抗菌肽基因的表达量分析 总被引:1,自引:0,他引:1
蓝藻水华可产生大量藻毒素,其中以微囊藻毒素危害最大。研究表明微囊藻毒素可影响包括虾类在内的多种水生生物的生长和繁殖,亦可导致虾类免疫系统受损。本研究通过实时荧光定量PCR(qRT-PCR)技术检测了在微囊藻毒素MC-LR作用下,凡纳滨对虾(Litopenaeus vannamei)体液免疫中3种主要的抗菌肽基因(Penaeidin 3、Crustin和ALF)的表达量变化情况,发现Penaeidin 3和ALF受到MC-LR影响较大,Crustin基因表达量虽有所上调,但变化不大。同时,通过再次注射鳗弧菌(Vibrio anguillarum)对3种抗菌肽在MC-LR影响下抗菌能力的检测,发现3种抗菌肽表现出相对一致的变化,即表达量均在前期下调,4 h后逐渐上调,在MC-LR处理组中的表达量低于对照组的趋势。结果表明MC-LR可能通过直接或间接的方式影响对虾3种抗菌肽基因的表达,对免疫系统造成损伤,致使对虾抗病能力减弱;这一结果表明,长期发生铜绿微囊藻水华的虾池对虾存活率下降,可能与微囊藻毒素影响对虾抗菌肽基因的表达有关。 相似文献
139.
为研究励珂健喷剂(主要成分:杨树花提取物)对10日龄内仔猪腹泻和免疫力的影响,将18头PIC母猪随机分成3组,每组6头,分别为蒸馏水组、土霉素组和励珂健喷剂组,蒸馏水组仔猪1、3、5日龄时皮肤喷洒蒸馏水1 m L/头/d,土霉素组仔猪3、7日龄时分别肌肉注射20%长效土霉素注射液0.2 m L/头/d、0.5m L/头/d,励珂健喷剂组仔猪1、3、5日龄时皮肤喷洒励珂健喷剂1 m L/头/d。结果表明,励珂健喷剂可有效降低10日龄内仔猪的腹泻率和发病率,且励珂健喷剂组腹泻仔猪的治愈速度快于土霉素组和蒸馏水组。由此证明:励珂健喷剂对10日龄内仔猪腹泻有防治作用,并且还可以增强仔猪的免疫力。 相似文献
140.
Hong-tao Chang Xiu-yuan He Yu-Feng Liu Lu Chen Quan-hai Guo Qiu-ying Yu Jun Zhao Xin-wei Wang Xia Yang Chuan-qing Wang 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):399-407
A recombinant replication-defective adenovirus expressing the major epitopes of porcine circovirus-2 (PCV-2) capsid protein (rAd/Cap/518) was previously constructed and shown to induce mucosal immunity in mice following intranasal delivery. In the present study, immune responses induced by intranasal immunization with a combination of rAd/Cap/518 and cytosine-phosphate-guanosine oligodeoxynucleotides (CpG ODN) were evaluated in mice. The levels of PCV-2-specific IgG in serum and IgA in saliva, lung, and intestinal fluids were significantly higher in the group immunized with rAd/Cap/518 and CpG ODN than animals immunized with rAd/Cap/518 alone. The frequencies of IL-2-secreting CD4+ T cells and IFN-γ-producing CD8+ T cells were significantly higher in the combined immunization group than mice immunized with rAd/Cap/518 alone. The frequencies of CD3+, CD3+CD4+CD8-, and CD3+CD4-CD8+ T cells in the combined immunization group were similar to that treated with CpG ODN alone, but significantly higher than mice that did not receive CpG ODN. PCV-2 load after challenge in the combined immunization group was significantly lower than that in the phosphate-buffered saline placebo group and approximately 7-fold lower in the group treated with CpG ODN alone. These results indicate that rAd/Cap/518 combined with CpG ODN can enhance systemic and local mucosal immunity in mice, and represent a promising synergetic mucosal vaccine against PCV-2. 相似文献