Fundamentals of host immune response against Brucella abortus: what the mouse model has revealed about control of infection     

Baldwin CL  Parent M 《Veterinary microbiology》2002,90(1-4):367-382

The studies reviewed here evaluated the role cellular immune system components play in control of brucellosis by conducting comparative studies with brucella-resistant C57BL/10 or C57BL/6 mice and susceptible BALB/c mice. We have shown by both in vitro and in vivo studies that activation of macrophages with interferon-gamma (IFN-γ) is an important factor for control of infection with B. abortus in the mouse model and that the mechanism of anti-brucella activity largely involved reactive oxygen intermediates. Differences in control of the organism by resistant and susceptible mice was not related to inherent differences in the ability of their macrophages to control infection either with or without IFN-γ activation nor was it attributable to NK cells since we found no role for them in control of brucellosis in either mouse strain. However, relative resistance to brucellosis did correlate with increased production of IFN-γ by CD4 T cells during the first weeks after infection while IL-10 contributed to susceptibility in BALB/c mice. Moreover, by 3 weeks post-infection splenocytes from the susceptible BALB/c mice failed to produce IFN-γ and relied on TNF- as well as CD8 T cells to control infection until the end of the plateau phase around 6 weeks post-infection when IFN-γ production resumed and clearance began. In contrast, IFN-γ was crucial for control throughout the infection in the more resistant C57BL/6 mice and the mice died in its absence by 6 weeks post-infection compared to 12 weeks for the more susceptible mice that relied on additional mechanisms of control. In contrast to the IFN-γ knock-out mice, both β2 microglobulin knock-out C57BL/6 mice, which do not express conventional MHC class I molecules and thus cannot present antigen to CD8 T cells, or perforin knock-out C57BL/6 mice, which have no T cell cytotoxic activity, controlled and cleared the infection as well as normal C57BL/6 mice. The hiatus of IFN-γ production in BALB/c mice correlated with very high levels of total IL-12 and it was postulated that the lack of IFN-γ was a consequence of p40 homodimer blocking activity. However, reduction of p40 IL-12 in vivo through administration of indomethacin reduced the infection without a concomitant measurable increase in IFN-γ. Current studies are aimed at elucidating the mechanism of the IFN-γ hiatus.  相似文献   

Anticoccidial Vaccination of Broiler Chickens in Various Management Programmes: Relationship between Oocyst Accumulation in Litter and the Development of Protective Immunity     

Williams RB  Johnson JD  Andrews SJ 《Veterinary research communications》2000,24(5):309-325

Paracox anticoccidial vaccine was administered to a 7-day-old flock of commercial broiler breeder stock subsequently reared to point-of-lay in the same house. For comparison, three subgroups of another flock of broiler breeders were also vaccinated with Paracox at 7 days of age, reared to 42 days and then transferred to new litter on another farm until point-of-lay. The first subgroup received no further treatment, but the second and third each received a second vaccination with Paracox, either immediately after transfer to the new litter or 42 days after transfer. Using an Eimeria necatrix model, protective immunity was demonstrated by virulent challenge of samples of birds from all groups by the age of 37–40 days (30–33 days after the first vaccination), and was maintained to at least 122–125 days of age, whether the birds remained on the same litter or were transferred to another farm, and whether they received one or two anticoccidial vaccinations. Therefore, there is no disadvantage in transferring birds onto new litter 35 days after a single Paracox vaccination, nor is there any advantage in giving a second vaccination after such a transfer. Vaccinated birds seeded the new litter with oocysts, despite being clinically immune to coccidiosis. A supplementary laboratory experiment showed that birds vaccinated at 8 days of age passed almost no oocysts after a second vaccination at 43 days of age. This indicated that they were not only protected against clinical coccidiosis, but were almost solidly immune to a homologous infection 5 weeks after a single vaccination. Nevertheless, oocysts appeared in the litter of all four groups of commercial breeders throughout the trial, showing that wild-type heterologous infections occurred whether the birds were transferred to new litter or not, but these did not overwhelm the acquired protective immunity and cause clinical coccidiosis.  相似文献   

黄芪多糖对人工感染IBDV雏鸡红细胞免疫功能的影响   总被引：1，自引：0，他引：1  

李宏全  武彩红高海 宋建德 《中国兽医科技》2006,36(1):74-79

将由未免疫接种腔上囊病疫苗鸡的种蛋孵化而来的160只1日龄海兰白雏鸡随机分为A、B、C和D共4组。A组为对照组，B、C和D组于26日龄时按每只0．3mL的剂量用IBDV攻毒。A、B组未用黄芪多糖（APS）处理，C、D组从攻毒当日起连续胸肌注射APS6d，剂量分别为每只鸡5mg和10mg。分别在21、29、32、35、38日龄时心脏采血1～3mL，测定E—C3bRR、E—ICRR、ERER和ERIR。结果显示，雏鸡感染IBDV后可使E-C3bRR和ERER显著降低（P〈0．01）；APS处理组E-C3bRR、E-ICRR、ERER均高于A、B组（P〈0．01），其中D组最高，而ERIR则与A组相似。证实，雏鸡感染IBDV后红细胞免疫功能低下，而APS可显著提高其红细胞免疫功能。  相似文献   

牛病毒性腹泻病毒持续感染的免疫学研究进展     

钟发刚  王新华  程安春 《动物医学进展》2006,27(Z1):13-15

牛病毒性腹泻病毒(BVDV)是危害养牛业的重要病原之一。BVDV感染能够引起广泛的临床症状,包括牛病毒性腹泻-黏膜病、持续感染、免疫耐受、繁殖障碍、血小板减少与出血综合征等。由于其病原的复杂性,给该病的控制及疫苗研制带来了一定的困难。近年来,对其免疫学的研究取得了一定进展,特别是在病原的基本免疫学特征、体液免疫、细胞免疫、免疫耐受和免疫调节方面做了深入研究,同时也在参与免疫应答的细胞因子方面做了研究,这些都为牛病毒性腹泻-黏膜病的预防和控制研究提供了新的思路。  相似文献   

共轭亚油酸对动物免疫功能的调节   总被引：2，自引：0，他引：2  

荆丽珍  王宝维  张旭晖  王亚超  岳斌 《中国饲料》2006,(14):14-16

共轭亚油酸具有广泛的生物学功能,它对增加机体免疫球蛋白含量,促进免疫细胞增殖、细胞因子产生、吞噬细胞的功能,基因表达都具有调节作用。本文就共轭亚油酸的免疫调节作用进行了阐述。  相似文献   

不同佐剂新城疫疫苗对鸡体液免疫的影响   总被引：1，自引：0，他引：1  

穆杨  周丽梅  吕娟  李楠  李煜隆  黄强力 《中国家禽》2007,29(19):12-14

佐剂是疫苗研究的重要组成部分.选择合适的佐剂不仅可以增强疫苗的免疫效果,而且可以提高机体的抵抗力.不同佐剂对体液免疫会产生不同的作用.本研究选用白油佐剂、弗氏佐剂和蜂胶佐荆与新城疫病毒抗原混合制成疫苗,免疫雏鸡,探讨不同佐剂对鸡体液免疫的影响.结果表明,三种佐剂疫苗均有保护力,试验鸡饲养至61日龄均未发生新城疫,其中弗氏佐剂的效果最好,蜂胶佐剂的效果次之,油佐剂组检测到雏鸡61日龄时仍未出现抗体高峰值.  相似文献   

Enhancement of protective immune responses by oral vaccination with Saccharomyces cerevisiae expressing recombinant Actinobacillus pleuropneumoniae ApxIA or ApxIIA in mice     

Sung Jae Shin  Seung Won Shin  Mi Lan Kang  Deog Yong Lee  Moon-Sik Yang  Yong-Suk Jang  Han Sang Yoo 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(4):383-392

We previously induced protective immune response by oral immunization with yeast expressing the ApxIIA antigen. The ApxI antigen is also an important factor in the protection against Actinobacillus pleuropneumoniae serotype 5 infection; therefore, the protective immunity in mice following oral immunization with Saccharomyces cerevisiae expressing either ApxIA (group C) or ApxIIA (group D) alone or both (group E) was compared with that in two control groups (group A and B). The immunogenicity of the rApxIA antigen derived from the yeast was confirmed by a high survival rate and an ApxIA-specific IgG antibody response (p < 0.01). The highest systemic (IgG) and local (IgA) humoral immune responses to ApxIA and ApxIIA were detected in group E after the third immunization (p < 0.05). The levels of IL-1β and IL-6 after challenge with an A. pleuropneumoniae field isolate did not change significantly in the vaccinated groups. The level of TNF-α increased in a time-dependent manner in group E but was not significantly different after the challenge. After the challenge, the mice in group E had a significantly lower infectious burden and a higher level of protection than the mice in the other groups (p < 0.05). The survival rate in each group was closely correlated to the immune response and histopathological observations in the lung following the challenge. These results suggested that immunity to the ApxIA antigen is required for optimal protection.  相似文献   

铝中毒对蛋鸡白细胞和红细胞免疫功能的影响   总被引：4，自引：0，他引：4  

刘福堂  李艳飞  顾庆云 《中国畜牧兽医》2007,34(10):70-72

采用连续腹腔注射相同体积不同浓度梯度的三氯化铝，建立不同程度的鸡亚慢性铝中毒型，检测铝中毒雏鸡外周血白细胞数(WBC)、淋巴细胞总数、ANAE+T数及红细胞C3b受体花环率和红细胞免疫复合物花环率。结果表明，铝中毒雏鸡外周血白细胞数、淋巴细胞总数、ANAE+T数及红细胞C3b受体花环率均明显低于健康对照组雏鸡，而红细胞免疫复合物花环率明显高于健康对照组雏鸡。上述结果说明, 铝中毒对雏鸡细胞免疫和非特异性免疫功能有明显的抑制作用。  相似文献   

脂肪对家禽免疫的影响     

王新卫  贾强  周彦 《中国畜牧兽医》2007,34(11):22-25

营养因素对家禽免疫具有重要作用。脂肪是家禽必需的重要营养元素之一，不仅是维持家禽正常生长、繁殖、生产不可缺少的组成成分与营养物质，也是调节家禽免疫器官、组织和免疫应答反应不可缺少的物质基础。作者从脂肪的生理营养功能，就其对家禽的免疫器官发育、体液免疫、细胞免疫、非特异性免疫、细胞因子产生的影响等方面进行了综述。为合理配制家禽日粮，提高家禽抵抗疾病的能力提供理论依据。  相似文献   

乳腺分泌物中体细胞的研究进展     

钟凯  王艳玲  杨国宇 《中国畜牧兽医》2006,33(12):39-42

不同物种的乳腺分泌物中含有的细胞成分被称为体细胞,其中包括淋巴细胞、白细胞、巨噬细胞和上皮细胞。物种、乳腺感染情况、不同生理阶段和饲养管理条件等因素均会影响乳中的体细胞数量和细胞类型。近年来,乳中体细胞得到了人们的关注和深入研究,显示出广阔的应用前景。人们利用从初乳和常乳中得到的乳腺上皮细胞已经成功进行了乳腺细胞的原代培养和建立了乳腺细胞系,为乳生成、被动免疫转移和乳腺癌的研究提供了良好平台。体细胞中提取的RNA代表了乳腺组织的基因表达,因此为研究乳腺组织的基因表达提供了方便、良好的来源。  相似文献