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51.
冻干水痘减毒活疫苗最小免疫剂量的研究 总被引:2,自引:0,他引:2
通过临床研究确定冻干水痘减毒活疫苗的最小免疫剂量 ,为制定规程中的免疫剂量提供科学依据。观察对象接种不同免疫剂量的冻干水痘减毒活疫苗后 ,于接种前和接种后 6周采血 ,采用荧光抗膜抗体 (FAMA)法检测其抗体阳转率和几何平均滴度 (GMT)。接种不同免疫剂量的疫苗 ,抗体阳转率差异无显著的统计学意义。疫苗中抗原含量在 2 5 0 0 0PFU/ml和 2 0 0 0PFU/ml之间 ,GMT差异无显著的统计学意义 ,但 2 5 0 0 0PFU/ml、2 0 0 0PFU/ml与 2 0 0PFU/ml之间抗体GMT的差异有极显著的统计学意义。研究结果表明 ,2 0 0 0PFU/ml为冻干水痘减毒活疫苗的最小免疫剂量。 相似文献
52.
Sertoli细胞诱导大鼠肝内胰岛移植物免疫豁免的实验研究 总被引:5,自引:3,他引:2
目的 探究睾丸Sertoli细胞能否对肝内共移植的胰岛移植物提供免疫豁免作用以及共移植的睾丸Sertoli细胞最佳数量。方法将同种大鼠胰岛及不同数量的睾丸Sertoli细胞同时移植于糖尿病受体的肝内,观察移植物存活情况、胰岛功能、并检测移植物内胰岛素和Fas配体(FasL)表达以及浸润淋巴细胞凋亡情况。结果单纯胰岛移植组平均存活期为(5.6±0.8)d,同时与胰岛细胞在肝内共移植的睾丸细胞数增加至1×107个时,平均存活期为(41.4±4.61)d,明显延长(P<0.05),胰岛移植物中有大量表达FasL的睾丸细胞和表达胰岛素的胰岛细胞.在移植物周围有大量浸润的淋巴细胞凋亡。结论睾丸Sertoli细胞与胰岛细胞同时在肝内共移植,通过诱导局部豁免而延长胰岛移植物的存活时间,且同时共移植1×107个Sertoli细胞时效果最好。 相似文献
53.
目的研究大鼠肝移植后自发免疫耐受的形成与移植肝内CD4~ CD25~ 调节性T细胞(Tr细胞)的关系。方法按供、受者不同将实验分为3组。急性排斥组:DA大鼠为供者,LEW大鼠为受者;自发耐受组:LEW大鼠为供者,DA大鼠为受者;同基因组:供、受者均为DA大鼠。各组均建立大鼠原位肝移植模型。分别在肝移植术后4、7、14、30和90 d时采用密度梯度离心法分离移植肝内淋巴细胞,免疫磁珠分离(MACS)法分选出CD4~ CD25~ Tr细胞;用流式细胞术(FCM)检测细胞纯度,同时分析CD4~ CD25~ Tr细胞比例的变化;体外细胞增殖试验研究CD4~ CD25~ Tr细胞对CD4~ CD25~-T细胞的免疫抑制作用。结果肝移植早期,急性排斥组和自发耐受组移植肝内CD4~ CD25~ Tr细胞比例均明显增加,其中急性排斥组增加更为明显;移植后4 d左右,两组CD4~ CD25~ Tr细胞比例开始下降,急性排斥组的下降幅度较大;移植后30 d,自发耐受组受者的移植肝内CD4~ CD25~ Tr细胞比例达到第2次高峰,约在移植后90 d时下降至正常生理水平。移植后7 d左右,急性排斥组受者均因发生排斥反应而死亡,而自发耐受组受者均存活。此外,CD4~ CD25~ Tr细胞能有效抑制CD4~ CD25~-T细胞的增殖。结论CD4~ CD25~ Tr细胞是一种具有特异免疫调节功能的T细胞亚群,其主动的免疫抑制功能可能是诱导大鼠肝移植自发免疫耐受的机制之一。 相似文献
54.
Fredrik Ghosh Karl Engelsberg Robert V. English Robert M. Petters 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(6):835-846
Background The purpose of this study was to explore neuroretinal transplantation in a large animal model of severe retinitis pigmentosa
and to establish graft development, long-term survival, graft-host integration, and effects on the host retina.
Methods Rhodopsin transgenic pigs, aged 6 months, received in one eye a fetal full-thickness neuroretinal sheet in the subretinal
space by means of vitrectomy and retinotomy. Six months postoperatively, eyes were studied in the light microscope and with
immunohistochemical markers. Full-field electroretinography (ERG) was performed at 4 and 6 months.
Results Laminated grafts with well-organized photoreceptors, rod bipolar cells, and Müller cells were found in five of six eyes. Neuronal
connections between graft and host retina were not seen. In the five eyes containing a graft, the number of surviving rods
in the host retina was significantly higher compared with unoperated eyes. The ERG did not reveal any significant difference
in b-wave amplitude between operated and control eyes, but the cone-derived response in operated eyes increased significantly
from 4 to 6 months while the rod response in control eyes decreased significantly.
Conclusions Fetal full-thickness neuroretina can be transplanted safely to an eye with severe retinal degeneration. In their major part,
the transplants develop a normal laminated morphology and survive for at least 6 months. Graft and host retinal neurons do
not form connections. Retinal function in the host is reduced initially by the surgical trauma, but the presence of a well-laminated
graft counteracts this effect and rescues rods from degeneration.
Supported by The Foundation Fighting Blindness (grant# C-NC02-798-0078), The Faculty of Medicine, University of Lund, The
Swedish Research Council, The Princess Margaretas Foundation for Blind Children, The 2nd ONCE International Award for New
Technologies for the Blind. 相似文献
55.
BALB/c mice are susceptible to a high-dose infection of the protozoan Leishmania major, which induces a parasite-specific antibody, Th2-like response, exclusive of a significant and protective cell-mediated Th1 component. We have shown, in contrast, that infection with a low number of parasites induces cell-mediated immunity exclusive of antibody production, and results in resistance to substantial subsequent high-dose infection. Low-dose exposure thus constitutes effective vaccination. In the present study, we analyze lymphokine production by parasite-specific T cells from these low-dose exposed, resistant mice and from normal, susceptible mice following high-dose infection. Two findings stand out. First, the parasite-specific T cells in mice rendered resistant appear not to be in an activated, effector state at the time of parasite challenge, as assessed by lack of lymphokine production on short-term stimulation with parasite antigens, but to be rather in a memory state. Second, the ratio of parasite antigen-dependent production of interferon-γ to that of interleukin-4 by spleen cells of low-dose exposed and normal mice upon high-dose challenge takes a dramatically different course. This ratio is similar in both groups of mice shortly after challenge, but increases dramatically in the resistant and declines dramatically in the control mice over a period of weeks, such that these ratios differ by about 60-fold 12 weeks after the high-dose challenge. In addition, we show that a similar state of resistance occurs following low-dose infection with a more virulent strain of L. major. In toto, our observations suggest that resistance may be generally achievable by low-dose exposure and may be associated with a memory state which, when activated by parasite challenge, results in the evolution of the response over weeks such that the protective, Th1 component becomes ever more dominant over the Th2 component. 相似文献
56.
背景 心血管疾病(CVD)是常见病和多发病,患病率和死亡率呈快速上升趋势。动脉粥样硬化(AS是缺血性CVD的病理基础,研究表明心外膜脂肪组织(EAT)通过分泌外泌体(EXO)和生物活性物质促进AS进展,但其作用机制仍需进一步研究。目的 通过生物信息学方法挖掘冠状动脉粥样硬化性心脏病(CAD)患者EAT中的关键基因,探讨免疫细胞浸润情况,联合CAD患者EXO间差异表达基因(DEGs)推测EAT来源EXO间DEGs并进行验证,从细胞及分子水平上探讨EAT在CAD疾病过程中的作用机制。方法 从基因表达综合数据库(GEO)中下载关于EAT的数据集GSE64554、GSE120774,根据临床信息将EAT的测序数据分为CAD组和健康对照组,使用R语言及相关软件包进行生物信息学分析。首先使用R语言筛选CAD组与健康对照组EAT间DEGs,并进行GO富集分析和KEGG通路富集分析,构建蛋白质-蛋白质相互作用(PPI)网络,评估所选基因的生物学功能及可能参与其调控的转录因子。构建GSE64554数据集中EAT的加权基因共表达网络(WGCNA),获取同CAD表型相关的基因模块,将所获EAT间DEGs与模... 相似文献
57.
Cytomegaloviruses encode homologs of cellular immune effector proteins, including chemokines (CKs) and CK receptor-like G protein-coupled receptors (GPCRs). Sequence of the guinea pig cytomegalovirus (GPCMV) genome identified an open reading frame (ORF) which predicted a 101 amino acid (aa) protein with homology to the macrophage inflammatory protein (MIP) subfamily of CC (β) CKs, designated GPCMV-MIP. To assess functionality of this CK, recombinant GPCMV-MIP was expressed in HEK293 cells and assayed for its ability to bind to and functionally interact with a variety of GPCRs. Specific signaling was observed with the hCCR1 receptor, which could be blocked with hMIP −1α in competition experiments. Migration assays revealed that GPCMV-MIP was able to induce chemotaxis in hCCR1-L1.2 cells. Antisera raised against a GST-MIP fusion protein immunoprecipitated species of ∼12 and 10 kDa from GPCMV-inoculated tissue culture lysates, and convalescent antiserum from GPCMV-infected animals was immunoreactive with GST-MIP by ELISA assay. These results represent the first substantive in vitro characterization of a functional CC CK encoded by a cytomegalovirus. 相似文献
58.
Henry Velazquez-Soto Fernanda Real Maria C Jim nez-Mart nez 《World Journal of Immunology》2022,12(1):1-8
Co-stimulatory molecules are key mediators in the regulation of immune responses and knowledge of its different families, structure, and functions has improved in recent decades. Understanding the role of co-stimulatory molecules in pathological processes has allowed the development of strategies to modulate cellular functions. Currently, modulation of co-stimulatory and co-inhibitory molecules has been applied in clinical applications as therapeutic targets in diseases and promising results have been achieved. 相似文献
59.
APA微胶囊免疫隔离生物膜制备中的质量控制 总被引:3,自引:0,他引:3
为了优化制备条件, 简化工艺, 控制质量, 本文观测了APA(海藻酸盐-聚赖氨酸-海藻酸盐)微胶囊免疫隔离生物膜制备过程中部分物理因素和化学因素与质量的关系.结果表明: 微囊的粒径与静电微囊发生仪脉冲频率呈负相关; 与推进泵速度呈正相关; 与针头内径呈正相关.随着聚赖氨酸浓度的增加, 膜厚度显著增加.微囊的粒径不随聚赖氨酸成膜反应时间延长而改变, 但影响膜的厚度.柠檬酸钠的液化时间对微囊的粒径与厚度均无明显影响.通过优化制备条件, APA微胶囊免疫隔离生物膜将具有更好的通透性、柔韧性、生物相容性和强度. 相似文献
60.
Federica Cavallo Alfonso Martin-Fontecha Matteo Bellone Silvia Heltai Evelina Gatti Paola Tornaghi Massimo Freschi Guido Forni Paolo Dellabona Giulia Casorati 《European journal of immunology》1995,25(5):1154-1162
Although the transfection of B7-1 cDNA into a few mouse tumor cell lines can induce anti-tumor T cell immunity, its expression alone is ineffective in many other tumor cell lines tested. We were interested to study what factors limit B7-1 co-stimulatory activity, and decided to investigate whether B7-1 requires the cooperation of ICAM-1 to provide the minimal co-stimulatory signal for establishing an efficient anti-tumor immunity. We show that the transfection of B7-1 cDNA into three ICAM-1+ (plasmocytoma J558L, T lymphomas EL-4 and RMA), but not into two ICAM-1? tumor cell lines (adenocarcinoma TS/A and melanoma B16.F1), is sufficient to induce their complete rejection in syngeneic mice. The expression of ICAM-1 is necessary for the rejection of the B7 expressing tumors, since the primary response elicited by B7-1+ EL-4 and RMA clones expressing reduced levels of ICAM-1 is severely reduced. Furthermore, super-transfection of ICAM-1 cDNA into B7-1+ adenocarcinoma and melanoma clones optimizes their primary rejection. Histologic examination of transfected tumors reveals that B7-1 and ICAM-1 exert a potent pro-inflammatory activity. The intra-tumor infiltration is composed of both eosinophils and lymphomono-cytes, and is already massive 5 days after the tumor challenge. The primary rejection of the B7-1+ ICAM-1+ tumors depends critically on CD8+ T cells, natural killer cells and granulocytes, but is independent of CD4+ T cells. Remarkably, in addition to its effects on the early phases of the immune response, the co-expression of ICAM-1 and B7-1 on tumors is also necessary for the efficient induction of a memory response. In fact, only the primary challenge with B7-1+, ICAM-1+ tumor cells protects the majority of the mice from a second injection of parental tumor cells. Collectively, our findings indicate that B7-1 and ICAM-1 are fundamental components for triggering the primary rejection of tumors and establishing a protective memory response. These findings may help to define new strategies for the rational application of co-stimulation in tumor immunotherapy. 相似文献