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为了分析IVIG抗补体活性测定出现负值与绵羊红细胞质量的关系。采用CH50试验测定IVIG ACA时,在被检样品和其他试验条件相同的情况下,比较了被污染的和未污染的绵羊红细胞对IVIG抗补体活性测定的影响。结果显示,使用被污染的绵羊红细胞(作为试验材料时所得的)检测10份样品ACA(%)均为负值;使用未污染的绵羊红细胞未出现负值。提示被污染的绵羊红细胞干扰了抗补体活性测定,从而引起CH50试验结果出现偏差。  相似文献   

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采用CH50试验法测定静脉注射用人免疫球蛋白(IVIG)抗补体活性(ACA),在中性pH条件下,比较了不同的Na^ 含量及不同种类的糖对ACA测定结果的影响。结果表明,NaCl含量由0.2%上升至1.0%时,ACA呈逐渐下降趋势;用5%葡萄糖作稳定剂时ACA最低。IVIG在37℃条件下放置一月后,ACA有明显下降趋势。在半成品配制过程中,pH及各种成份的加入顺序对ACA也有一定影响。  相似文献   

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热激蛋白gp96可特异性结合来源于肿瘤和病毒的抗原肽,与抗原呈递细胞表面CD91等受体作用进入胞内,并在内质网中将结合的抗原通过抗原呈递链呈递给MHCI类分子,激活特异性T细胞。同时,与细胞表面Toll样受体(TLR)TLR2、TLR4等相互作用,激活天然免疫。近期研究发现调节性T细胞(Treg)对gp96免疫功能有显著抑制作用,随着对影响gp96免疫功能的免疫抑制机制的深入了解,以及利用汉逊酵母表达有免疫活性的全长gp96蛋白体系的建立,gp96将在治疗肿瘤及传染性疾病中发挥更大的作用。  相似文献   

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手足口病是由多种肠道病毒感染导致的一种急性儿科传染病。近年来,我国肠道病毒71型 (EV71) 手足口病发病率急剧上升,重症病例时有报道,严重威胁儿童健康。临床上对于重症手足口病的治疗缺乏有效手段,主要以对症治疗和支持疗法为主。静脉注射人免疫球蛋白由健康献血员血浆提取纯化而来,含有包括EV71在内的多种肠道病毒的中和抗体,可作为重症手足口病被动免疫和免疫调节的重要手段,值得关注。  相似文献   

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为了更好地进行生产质量控制,快速、准确的测定静注人免疫球蛋白中的IgG含量。实验中对2001~2008年的静注人免疫球蛋白中的IgG含量检测结果进行了抽样统计分析。分析结果表明:样品40倍稀释后测得的吸光值与标准曲线第三点的吸光值无显著性差异;样品40倍稀释后测得的IgG含量与样品进行20、30、40倍三个稀释度测得的IgG含量的平均值无显著性差异。从而证明,样品40倍稀释后测得的IgG含量可以代表该批样品的IgG含量,无需进行20、30倍的稀释。检测方法会更省时、省力、省材料。  相似文献   

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A regulatory or suppressor T cell is functionally defined as a T cell that inhibits an immune response by influencing the activity of another cell type. On the other hand, Th1 cells express IFN-γ and mediate cellular immunity.Sclareol exhibits growth inhibition and cytotoxic activity against a variety of human cancer cell lines. In the first set of experiments, Sclareol was isolated from the plant Salvia sclarea and our study assessed the immuno-therapeutic effectiveness of Sclareol by direct intra-tumoral injection. Secondly, several immunological parameters such as splenocytes proliferation, intra-tumor CD4+CD25+Foxp3+ Treg cells, IFN-γ and IL-4 secretion and tumor size were assessed to evaluate the anti-tumoral immune response. By all means, the findings confirmed that the activity of Sclareol could reduce the tumor growth in vivo against breast cancer.  相似文献   

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A significant subset of head and neck carcinomas are infected with human papilloma virus; prophylactic vaccines can prevent such HPV+ cancers but are ineffective for invasive HPV+ cancers. We intend to make them therapeutic by means of systemic T regulatory cell depletion.  相似文献   

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Green tea leaves fermented with Aspergillus luchuensis var kawachii kitahara (Cha-Koji) are a health food containing live A. luchuensis. In this study, we examined the effects of Cha-Koji on the immune system and the enteric environment. First, we designed a clinical trial; after ingesting Cha-Koji daily for 28 days, blood parameters and the fecal composition of the participants were analyzed. Similarly, mice were administered (oral administration) with Cha-Koji suspension or its vehicle for 14 days. Thereafter, both humans and mice were examined by analyzing their immune cell phenotypes and intestinal microbiota. Regulatory T cell (Treg) numbers were significantly increased after administering Cha-Koji. An increase of Clostridium subcluster XIVa, that were known to be rich in butyrate-producing bacterium, was observed in human feces, but not in mice. These results suggest that Cha-Koji has the ability to increase Treg production in both humans and mice, irrespective of the presence of enteric butyrate.  相似文献   

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CD4+ T cells differentiate into subsets that promote immunity or minimize damage to the host. T helper 17 cells (Th17) are effector cells that function in inflammatory responses. T regulatory cells (Tregs) maintain tolerance and prevent autoimmunity by secreting immunosuppressive cytokines and expressing check point receptors. While the functions of Th17 and Treg cells are different, both cell fate trajectories require T cell receptor (TCR) and TGF-β receptor (TGF-βR) signals, and Th17 polarization requires an additional IL-6 receptor (IL-6R) signal. Utilizing high-resolution phosphoproteomics, we identified that both synergistic and additive interactions between TCR, TGF-βR, and IL-6R shape kinase signaling networks to differentially regulate key pathways during the early phase of Treg versus Th17 induction. Quantitative biochemical analysis revealed that CD4+ T cells integrate receptor signals via SMAD3, which is a mediator of TGF-βR signaling. Treg induction potentiates the formation of the canonical SMAD3/4 trimer to activate a negative feedback loop through kinases PKA and CSK to suppress TCR signaling, phosphatidylinositol metabolism, and mTOR signaling. IL-6R signaling activates STAT3 to bind SMAD3 and block formation of the SMAD3/4 trimer during the early phase of Th17 induction, which leads to elevated TCR and PI3K signaling. These data provide a biochemical mechanism by which CD4+ T cells integrate TCR, TGF-β, and IL-6 signals via generation of alternate SMAD3 complexes that control the development of early signaling networks to potentiate the choice of Treg versus Th17 cell fate.  相似文献   

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Urtica dentata Hand (UDH) is traditionally used in the Alpine region as a herbal medicine. Immunotherapy using total coumarins (TC) of UDH has been proposed, yet the cellular and molecular mechanisms remain incompletely characterized. Additionally, there is no method available for the quantification of the main coumarins in UDH. We describe maturation-resistant, TC-conditioned dendritic cell (DC), which expressed much lower MHC class II (I-Ak) and CD86, showed reduced capacity to stimulate effector T cell responses and upregulated PD-Ll (programmed death ligand-1). TC-DC-stimulated regulatory cells (Treg) were superior alloantigen-specific suppressor of the T effector response as compared to those stimulated by control (CTR)-DC. Furthermore, TC-conditioned DC increased the levels of Foxp3 and CTLA-4 in the CD25 T cell population. TC-DC downregulated toll like receptor 4 (TLR4) protein expression in response to LPS. This indicates that down-regulation of TLR4 in response to TC on DC is a critical signaling pathway that regulates the phenotype and function of DC. We also established a sensitive and specific high-performance liquid chromatography-diodearray detection-mass spectrometry (HPLC-DAD-MS) method for simultaneous identification of its main coumarins, 6,6',7,7'-tetramethoxyl-8,8'-biscoumarin (1), 7,7'-dihydroxy-6,6'-dimethoxy-8,8'-biscoumarin (2), 7,7'-dimethoxy-6,6'-biscoumarin (3), and scoparone (4). A demonstration of this mechanism and the method for identification and quantification of TC in UDH endorsed their potential as a tolerance-promoting herbal medicine to prevent or treat transplantation rejection and autoimmune diseases.  相似文献   

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Melanoma is an aggressive malignancy with poor prognosis. Eradication of tumor cells requires an effective interaction between melanoma cells and different players of the immune system. As the most potent professional antigen‐presenting cells, dendritic cells (DCs) play a pivotal role in mounting a specific immune response where their intratumoral and peritumoral density as well as their functional status are correlated with clinical staging of the disease and with patients’ survival. Under steady‐state conditions, internalization of apoptotic cells by immature DCs designates a state of tolerance to self‐antigens. Nevertheless, pathogens and necrotic cells interacting with pattern recognition receptors trigger downstream signaling pathways that evoke maturation of DCs, leading to the production of pro‐inflammatory cytokines. These mature DCs are essential for T‐cell priming and subsequent development of a specific immune response. Altered functions of DCs have an impact on the development of various disorders including autoimmune diseases and cancers. Herein, we focus on the checkpoints created throughout DCs antigen capturing and presentation to T cells, with subsequent development of either tolerance or immune response, with an emphasis on the role played by DCs in melanoma tumorigenesis and their therapeutic potential.  相似文献   

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选用不同核酸类型的脂包膜病毒,其中RNA病毒为水疱性口炎病毒(VSV),DNA病毒为伪狂犬病毒(PRV),将两种指示病毒分别用于验证一定浓度的辛酸盐对某一厂家生产的人血静脉注射用丙种球蛋白(IVIG)的病毒灭活效果。结果表明,液体IVIG在辛酸钠(0.7±0.2mmol/g蛋白)、pH(5.1±0.1)、29.5~30.5℃,孵放90min可灭活VSV和PRV,两种指示病毒的灭活效果分别为≥4.00~4.12和≥5.25~5.75log TCID50/0.1ml。因此,辛酸盐是一种安全、有效、快速的灭活脂包膜病毒的灭活剂。  相似文献   

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Cytotoxic T lymphocyte antigen-4 (CTLA-4) is an immune checkpoint molecule that is mainly expressed on activated T cells and regulatory T (Treg) cells that inhibits T-cell activation and regulates immune homeostasis. Due to the crucial functions of CTLA-4 in T-cell biology, CTLA-4-targeted immunotherapies have been developed for autoimmune disease as well as cancers. CTLA-4 is known to compete with CD28 to interact with B7, but some studies have revealed that its downstream signaling is independent of its ligand interaction. As a signaling domain of CTLA-4, the tyrosine motif plays a role in inhibiting T-cell activation. Recently, the lysine motif has been shown to be required for the function of Treg cells, emphasizing the importance of CTLA-4 signaling. In this review, we summarize the current understanding of CTLA-4 biology and molecular signaling events and discuss strategies to target CTLA-4 signaling for immune modulation and disease therapy.  相似文献   

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Fucoxanthin is a non-provitamin A carotenoid contained in brown seaweeds. We found that it suppressed interleukin-17 secretion from CD4+ T cells under IL-17-producing T (Th17) cell development conditions. By evaluating T cell differentiation in vitro, fucoxanthin and its metabolite fucoxanthinol inhibited T cell differentiation into Th17 cells. This suggests that fucoxanthin can improve inflammatory diseases due to Th17 cells.  相似文献   

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ObjectivesThis study aimed to clarify the dynamic changes of exhaustion features in T cells during oral carcinogenesis.Materials and MethodsMice were randomly divided into 4NQO group and control group. The exhaustion features of CD4+ and CD8+ T cells of both groups were detected by flow cytometry. Furthermore, multiplex immunohistochemistry was used to evaluate the expression of inhibitory receptors in human normal, dysplastic, and carcinogenesis tissues. Finally, anti‐PD‐1 antibody treatment was performed at the early premalignant phase of oral carcinogenesis.ResultsThe proportion of naive T cells in 4NQO group was lower than those in control group, while the proportion of effector memory T cells was higher in 4NQO group. The expression of inhibitory receptors on CD4+ and CD8+ T cells increased gradually during carcinogenesis. In contrast, the secretion of cytokines by CD4+ and CD8+ T cells decreased gradually with the progression stage. Strikingly, those changes occurred before the onset of oral carcinogenesis. The expression of inhibitory receptors on T cells increased gradually as the human tissues progressed from normal, dysplasia to carcinoma. Interestingly, PD‐1 blockade at the early premalignant phase could reverse carcinogenesis progression by restoring T cell function.ConclusionsT‐cell dysfunction was established at the early premalignant phase of oral carcinogenesis; PD‐1 blockade at the early premalignant phase can effectively reverse T‐cell exhaustion features and then prevent carcinogenesis progression.  相似文献   

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选用不同核酸类型的脂包膜病毒,其中RNA病毒为水疱性口炎病毒(VSV),DNA病毒为伪狂犬病毒(PRV),将两种指示病毒分别用于验证低pH孵放法对不同厂家生产的人血静脉注射用丙种球蛋白(IVIG)的病毒灭活效果。结果表明,液体IVIG的pH值为3.8~4.4,在23~25℃环境中,孵放21天可灭活VSV和PRV,两种指示病毒的灭活效果分别为≥5.50~6.62和≥5.38~6.62logTCID50/0.1ml。因此,低pH孵放法是一种安全、有效且简便实用的灭活脂包膜病毒的方法。  相似文献   

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