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1.
目的确定SHIV1157ipd3N4静脉途径感染中国恒河猴的有效病毒浓度,明确SHIV1157ipd3N4感染实验猴体内病毒复制和免疫损伤情况。方法 10只正常中国恒河猴分成6组,分别用10倍系列稀释的病毒液1 mL静脉感染,测定血浆病毒载量,CD4+/CD8+,CD4+T淋巴细胞绝对数,分析感染后恒河猴体内病毒复制和免疫损伤情况。结果 5TCID50/mL以上浓度的SHIV1157ipd3N4能通过静脉途径感染中国恒河猴。结论该实验的成功进行为SHIV/中国恒河猴疾病及评价模型的建立奠定了良好的基础,为今后使用此模型评价抗病毒药物或疫苗提供了条件。  相似文献   

2.
目的制备SIVmac239恒河猴(Macaca mulatta)细胞适应株病毒,模拟HIV性传播感染特点进行恒河猴直肠黏膜感染研究,探索引起系统性感染的病毒阈值水平与机体病毒、免疫学之间相关性,为我国艾滋病黏膜疫苗等生物制剂有效性评价提供新的模型构建思路。方法参照HIV性传播自然感染剂量范围,选用SIVmac239连续升高的3种剂量直肠黏膜途径感染两只恒河猴,采取多种方法进行病毒血症和免疫反应特点分析。结果两只恒河猴经2×101TCID50和2×102TCID50病毒滴度2次攻击后45d,经检测均未建立系统性感染,病毒特异性免疫反应均为阴性;第3次2×103TCID50病毒滴度攻击后,M296猴表现出典型的系统性感染特点,并诱导特异性免疫反应。结论确认了HIV性传播过程中的病毒剂量效应关系,为预防性生物制剂的猴体有效性评价提供了新的思路。同时,发现SIVmac239Gag区特异性的T细胞免疫反应在病毒控制过程中发挥了关键作用,对于新一代艾滋病黏膜疫苗的抗原选择具有指导性意义。  相似文献   

3.
恒河猴Mamu-A^*01基因与SIV/SHIV感染相关的研究进展   总被引:2,自引:2,他引:0  
SIV/SHIV感染的恒河猴是研究艾滋病及艾滋病药物筛选、疫苗评价较理想的动物模型。MHC在细胞免疫中起着关键作用,研究表明,MHC-I类分子的多态性与SIV/SHIV感染者的疾病进展有着明显的关联作用,Mamu-A^*01是恒河猴中的一种MHC-I类分子,它可以呈递特定的病毒蛋白片段到细胞的表面,从而激发CTL反应。国外发现Mamu-A^*01阳性的猴艾滋病恒河猴会出现疾病进展缓慢,存活时间长等特征。本文就恒河猴Mamu-A^*01基因与SIV/SHIV感染相关的研究进展做一综述,以期进一步加深对MHC在疫苗研究中的作用的了解,并促进更行之有效地对HIV/AIDS疫苗进行评价。  相似文献   

4.
目的为了进一步确证SHIV-KB9感染中国恒河猴的病毒浓度范围,测试动物对病毒的适应性,明确该动物模型的可重复性。方法实验前采集猴血清并进行血清学检查。选出4只无SIV、STLV、SRV/D和B病毒感染的恒河猴,分别用10倍系列稀释的病毒液静脉感染实验猴,使用流氏细胞术、血常规、病毒分离、DNA-PCR和RT-PCR等方法确定实验猴是否被感染,以及感染后恒河猴体内病毒复制和免疫细胞损伤情况。结果实验猴的血浆病毒载量、病毒分离结果、CD4+/CD8+比值和CD4+T细胞数等证实,4.8×105 copies/mL以上浓度的SHIV-KB9病毒液能成功感染中国恒河猴。结论本研究进一步明确了SHIV-KB9感染中国恒河猴的有效病毒浓度范围,确定了SHIV-KB9病毒感染中国恒河猴的病毒学、免疫学的测定指标,成功的建立了SHIV-KB9/中国恒河猴动物模型。  相似文献   

5.
目的 为准确检测艾滋病猴模型特异性细胞免疫,优化、确定胞内细胞因子染色(ICS)影响因素和条件.方法 使用三种多克隆激活剂分别刺激SIV感染猴外周血单个核细胞(PBMC),确定最佳阳性刺激物和刺激时间;然后使用五种浓度SIVmac239混合肽库分别刺激SIV感染猴PBMC,体外培养,不同时间点进行细胞染色和流式检测,确定肽库的最适刺激浓度和最佳刺激时间.最后,初步应用该方法检测SIV感染猴细胞免疫水平.结果 PMA+离子霉素组合可用作本实验的阳性刺激物;2μg/mL肽库,37℃5% CO2培养16 h,能更有效的刺激T细胞分泌TNF-α、IL-2、IFN-γ.结论 该方法的优化对艾滋病药物的临床前评价和疫苗研发等研究具有重要意义.  相似文献   

6.
目的了解SHIVKU一1静脉途径感染中国恒河猴的感染特点及进展规律。方法两只健康中国恒河猴,静脉感染SHIVKU-1病毒,定期采样检测血浆病毒载量、CD4+/CD8+比值、CD4+T细胞绝对数变化和血清中抗SHIVKU-1特异性IgG抗体水平。多色流式技术分析外周血、腹股沟淋巴结和十二指肠粘膜固有层CD4+T淋巴细胞记忆细胞亚群变化。结果两只实验猴成功感染SHIVKU-1病毒,一直到感染后3个月均保持稳定水平的病毒载量。外周血CD4+T淋巴细胞下降明显,CD4+/CD8+T细胞比值严重倒置。CD4+Tcm细胞比例在经历了感染早期的下降后,大幅升高,尤其是外周血和淋巴结。CD4+Tem则在粘膜固有层中增加明显。结论SHIVKU.1静脉途径成功感染了中国恒河猴,为SHIV/中国恒河猴疾病及评价模型的建立奠定了良好的基础,为今后使用此模型评价抗病毒药物或疫苗提供了条件。  相似文献   

7.
目的分析SIVmac239感染早期中国恒河猴回肠派氏淋巴结淋巴细胞数量及亚群的变化,探讨这些变化与疾病进展的可能关系。方法以静脉注射SIVmac239制备恒河猴AIDS模型,对回肠派氏淋巴结进行CD4和CD8免疫组化标记,分离Peyer’s集合淋巴结淋巴细胞,分别标记CD3、CD4、CD8、CD28、CD95单克隆抗体,以流式细胞仪检测T细胞及其亚群的表达情况。结果 SIVmac239感染急性期中国恒河猴Peyer淋巴结中CD4+/CD8+比值持续下降,记忆性细胞比例升高,但Peyer淋巴结形态及CD4+T细胞数量未见明显变化,CD8+T细胞从第5天开始持续升高。结论 SIVmac239感染急性期,中国恒河猴回肠派氏淋巴结形态及CD4+T细胞数量基本维持,向记忆性细胞的转化增加,但是CD4+/CD8+比值下降。  相似文献   

8.
本文旨在根据前期研究建立的恒河猴感染动物模型,对同期研制的肠道病毒71型(EV71)实验性灭活疫苗免疫动物进行全面的免疫保护性评价。评价指标包括病毒攻击后动物体内病毒载量及病理学变化,根据所得结果进行实验性疫苗免疫后动物在病毒攻击中的感染动力学分析。3个疫苗剂量(20、80、320EU)免疫的恒河猴均出现不同效价的中和抗体,80EU和320EU剂量组在二次免疫后第6周抗体效价达1∶128~1∶256,经104.5CCID50病毒鼻腔攻击后均未检出阳性病毒载量。20EU剂量组中,淋巴器官、中枢神经系统及其他主要脏器均出现比对照组低但仍为阳性的病毒增殖现象。病理学方面,各剂量组免疫恒河猴的中枢神经系统以及肺等器官均未出现相关病理损伤。本实验在确定该疫苗对恒河猴有效保护性的同时,亦为明确EV71灭活疫苗免疫剂量提供了直接的实验依据。  相似文献   

9.
目的探讨艾滋病急性期炎症因子、脂类代谢及葡萄糖代谢对体重的影响。方法检测SIVmac239感染北平顶猴急性期炎症因子(TNF-α、IL-6)、脂类代谢(胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇)及葡萄糖代谢参数(胰岛素、胰岛素抵抗指数),比较体重增加组和体重减少组SIV感染北平顶猴之间的差异,运用Pearson相关分析探讨胰岛素抵抗与血浆病毒载量的相关性。结果在SIVmac239感染北平顶猴急性期,炎症因子和血脂四项在体重增加组与体重减少组之间无明显差异;体重增加组胰岛素水平明显下降,体重减少组胰岛素水平明显升高,并出现胰岛素抵抗表现;Pearson分析显示,感染后第5周及第11周胰岛素抵抗指数变化与血浆病毒载量呈正相关。结论 SIVmac239感染急性期,葡萄糖代谢异常可能是导致北平顶猴体重变化的主要原因。  相似文献   

10.
目的研究当艾滋病恒河猴模型的血浆病毒载量处于低水平或阴性时,猴免疫缺陷病毒(simian immunodeficiency viruses,SIV)在宿主组织中的分布情况。方法SIVmac251感染恒河猴10只,定期检测其血浆载量,感染病毒平均高峰时间第14天时,活检取淋巴结。选取感染18个月后病毒载量最低水平和阴性的2只艾滋病猴(SAIDS),经安死术后取淋巴结、脾、肝、肺、肾、脑等组织,用原位杂交和实时荧光定量PCR的方法检测病毒在组织中的分布和组织中的病毒载量。结果感染后14d,10只猴血浆病毒载量达到10^7copies/mL,淋巴结组织病毒载量为10^5-10^8copies/g,原位杂交方法在腹股沟淋巴结中检测到强阳性斑点。感染后第18个月的2只猴,血浆病毒载量下降并维持不高于10^2copies/mL水平或阴性,但组织分布不尽相同,在肠系膜淋巴结、肾上腺、海马回、空肠、脾脏等组织中检测到10^5-10^6copies/g的病毒载量,于一只猴的脑积液中检测到10^3copies/mL的病毒载量。用原位杂交的方法在肠系膜淋巴结和空肠中检测到强阳性斑点,其它组织中未检测到阳性斑点。结论实验证实SAIDS猴在血浆病毒载量低甚至阴性时,病毒在不同组织中仍有分布,有些组织中甚至出现高病毒载量,提示在制备SIV/SAIDS模型中,尤其在药物筛选和疫苗评价时,应考虑组织病毒载量指标的测定和药物、疫苗对组织病毒的治疗清除作用的评价。  相似文献   

11.
Although the cellular immune response is essential for controlling SIV replication in Asian macaques, its role in maintaining nonpathogenic SIV infection in natural hosts such as sooty mangabeys (SM) remains to be defined. We have previously shown that similar to rhesus macaques (RM), SM are able to mount a T lymphocyte response against SIV infection. To investigate early control of SIV replication in natural hosts, we performed a detailed characterization of SIV-specific cellular immunity and viral control in the first 6 mo following SIV infection in SM. Detection of the initial SIV-specific IFN-γ ELISPOT response in SIVsmE041-infected SM coincided temporally with a decline in peak plasma viremia and was similar in magnitude, specificity, and breadth to SIVsmE041-infected and SIVmac239-infected RM. Despite these similarities, SM showed a greater reduction in postpeak plasma viremia and a more rapid disappearance of productively SIV-infected cells from the lymph node compared with SIVmac239-infected RM. The early Gag-specific CD8(+) T lymphocyte response was significantly more polyfunctional in SM compared with RM, and granzyme B-positive CD8(+) T lymphocytes were present at significantly higher frequencies in SM even prior to SIV infection. These findings suggest that the early SIV-specific T cell response may be an important determinant of lymphoid tissue viral clearance and absence of lymph node immunopathology in natural hosts of SIV infection.  相似文献   

12.
We used the rhesus macaque model of heterosexual human immunodeficiency virus (HIV) transmission to test the hypothesis that in vitro measures of macrophage tropism predict the ability of a primate lentivirus to initiate a systemic infection after intravaginal inoculation. A single atraumatic intravaginal inoculation with a T-cell-tropic molecular clone of simian immunodeficiency virus (SIV), SIVmac239, or a dualtropic recombinant molecular clone of SIV, SIVmac239/1A11/239, or uncloned dualtropic SIVmac251 or uncloned dualtropic simian/human immunodeficiency virus (SHIV) 89.6-PD produced systemic infection in all rhesus macaques tested. However, vaginal inoculation with a dualtropic molecular clone of SIV, SIVmac1A11, resulted in transient viremia in one of two rhesus macaques. It has previously been shown that 12 intravaginal inoculations with SIVmac1A11 resulted in infection of one of five rhesus macaques (M. L. Marthas, C. J. Miller, S. Sutjipto, J. Higgins, J. Torten, B. L. Lohman, R. E. Unger, H. Kiyono, J. R. McGhee, P. A. Marx, and N. C. Pedersen, J. Med. Primatol. 21:99–107, 1992). In addition, SHIV HXBc2, which replicates in monkey macrophages, does not infect rhesus macaques following multiple vaginal inoculations, while T-cell-tropic SHIV 89.6 does (Y. Lu, P. B. Brosio, M. Lafaile, J. Li, R. G. Collman, J. Sodroski, and C. J. Miller, J. Virol. 70:3045–3050, 1996). These results demonstrate that in vitro measures of macrophage tropism do not predict if a SIV or SHIV will produce systemic infection after intravaginal inoculation of rhesus macaques. However, we did find that the level to which these viruses replicate in vivo after intravenous inoculation predicts the outcome of intravaginal inoculation with each virus.  相似文献   

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14.
BACKGROUND: Progesterone administration prior to intravaginal challenge with pathogenic SIVmac239 decreases the protective efficacy of live attenuated vaccines in rhesus macaques. METHODS: To determine if progesterone alters the efficacy of live attenuated vaccines through local or systemic effects, seven male rhesus macaques were immunized with SHIV89.6 and then challenged intravenously with SIVmac239. Three of these animals were treated with Depo-Provera 30 days prior to the SIV challenge. RESULTS: The SHIV animals had significantly lower plasma viral RNA levels than the unimmunized control monkeys, but the Depo-Provera treated, SHIV-immunized animals did not. Despite the lack of protection, the Depo-Provera SHIV animals had strong SIV specific T-cell responses. However, altered patterns of NK frequency and CD38 T-cell expression prior to SIV challenge were observed in Depo-Provera SHIV animals. CONCLUSIONS: Depo-Provera eliminates live-attenuated lentivirus vaccine efficacy in male rhesus monkeys through systemic effects on antiviral immunity and/or viral replication.  相似文献   

15.
To evaluate how viral variants may affect disease progression in human pediatric AIDS, we studied the potential of three simian immunodeficiency virus (SIV) isolates to induce simian AIDS in newborn rhesus macaques. The three virus isolates were previously shown to range from pathogenic (SIVmac251 and SIVmac239) to nonpathogenic (SIVmac1A11) when inoculated intravenously into juvenile and adult rhesus macaques. Six newborn macaques inoculated with pathogenic, uncloned SIVmac251 developed persistent, high levels of cell-associated and cell-free viremia, had no detectable antiviral antibodies, and had poor weight gain; these animals all exhibited severe clinical disease and pathologic lesions diagnostic for simian AIDS and were euthanatized 10 to 26 weeks after inoculation. Two newborns inoculated with pathogenic, molecularly cloned SIVmac239 developed persistent high virus load in peripheral blood, but both animals had normal weight gain and developed antiviral antibodies. One of the SIVmac239-infected neonates exhibited pathologic lesions diagnostic for SAIDS and was euthanatized at 34 weeks after inoculation; the other SIVmac239-infected neonate remained alive and exhibited no significant clinical disease for more than 1 year after inoculation. In contrast, three newborn rhesus macaques inoculated with the nonpathogenic molecular clone, SIVmac1A11, had transient, low-level viremia, seroconverted by 10 weeks after inoculation, had normal weight gain, and remained healthy for over 1 year. These results indicate that (i) newborn rhesus macaques infected with an uncloned, virulent SIVmac isolate have a more rapid, fulminant disease course than do adults inoculated with the same virus, (ii) the most rapid disease progression is associated with lack of a detectable humoral immune response in SIV-infected infant macaques, (iii) a molecularly cloned, attenuated SIV isolate is nonpathogenic in neonatal macaques, and (iv) SIV-infected neonatal macaques exhibit patterns of infection, virus load, and disease progression similar to those observed in human immunodeficiency virus-infected children. This SIV/neonatal rhesus model of pediatric AIDS provides a rapid, sensitive model with which to compare the virulence of SIV isolates and to study the mechanisms underlying the differences in disease progression in human immunodeficiency virus-infected infants.  相似文献   

16.
Sooty mangabeys are a natural host of simian immunodeficiency virus (SIV) that remain asymptomatic and do not exhibit increased immune activation or increased T-lymphocyte turnover despite sustained high levels of SIV viremia. In this study we asked whether an altered immune response to SIV contributes to the lack of immunopathology in sooty mangabeys as opposed to species with pathogenic lentivirus infection. SIV-specific cellular immune responses were investigated in a cohort of 25 sooty mangabeys with natural SIV infection. Gamma interferon (IFN-gamma) enzyme-linked immunospot (ELISPOT) assay responses targeting a median of four SIV proteins were detected in all 25 mangabeys and were comparable in magnitude to those of 13 rhesus macaques infected with SIVmac251 for more than 6 months. As with rhesus macaques, Th2 ELISPOT responses to SIV were absent or >10-fold lower than the IFN-gamma ELISPOT response to the same SIV protein. The SIV-specific ELISPOT response was predominantly mediated by CD8+ T lymphocytes; the frequency of circulating SIV-specific CD8+ T lymphocytes ranged between 0.11% and 3.26% in 13 mangabeys. Functionally, the SIV-specific CD8+ T lymphocytes were cytotoxic; secreted IFN-gamma, tumor necrosis factor alpha, and macrophage inflammatory protein 1beta; and had an activated effector phenotype. Although there was a trend toward higher frequencies of SIV-specific CD8+ T lymphocytes in mangabeys with lower viral loads, a significant inverse correlation between SIV viremia and SIV-specific cellular immunity was not detected. The consistent detection of Th1-type SIV-specific cellular immune responses in naturally infected sooty mangabeys suggests that immune attenuation is neither a feature of nor a requirement for maintenance of nonpathogenic SIV infection in its natural host.  相似文献   

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To characterize the occurrence, frequency, and kinetics of retroviral recombination in vivo, we intravaginally inoculated rhesus macaques, either simultaneously or sequentially, with attenuated simian immunodeficiency virus (SIV) strains having complementary deletions in their accessory genes and various degrees of replication impairment. In monkeys inoculated simultaneously with SIVmac239Deltavpx/Deltavpr and SIVmac239Deltanef, recombinant wild-type (wt) virus and wild-type levels of plasma viral RNA (vRNA) were detected in blood by 2 weeks postinoculation. In monkeys inoculated first with SIVmac239Deltavpx/Deltavpr and then with SIVmac239Deltanef, recombination occurred but was associated with lower plasma vRNA levels than plasma vRNA levels seen for monkeys inoculated intravaginally with wt SIVmac239. In one monkey, recombination occurred 6 weeks after the challenge with SIVmac239Deltanef when plasma SIVmac239Deltavpx/Deltavpr RNA levels were undetectable. In monkeys inoculated first with the more highly replicating strain, SIVmac239Deltanef, and then with SIVmac239Deltavpx/Deltavpr, wild-type recombinant virus was not detected in blood or tissues. Instead, a virus that had repaired the deletion in the nef gene by a compensatory mutation was found in one animal. Overall, recombinant SIV was eventually found in four of six animals intravaginally inoculated with the two SIVmac239 deletion mutants. These findings show that recombination can occur readily in vivo after mucosal SIV exposure and thus contributes to the generation of viral genetic diversity and enhancement of viral fitness.  相似文献   

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