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11.
Most vaccines approved by regulatory bodies are administered via intramuscular or subcutaneous injections and have shortcomings, such as the risk of needle-associated blood infections, pain and swelling at the injection site. Orally administered vaccines are of interest, as they elicit both systemic and mucosal immunities, in which mucosal immunity would neutralize the mucosa invading pathogen before the onset of an infection. Hence, oral vaccination can eliminate the injection associated adverse effects and enhance the person's compliance. Conventional approaches to manufacturing oral vaccines, such as coacervation, spray drying, and membrane emulsification, tend to alter the structural proteins in vaccines that result from high temperature, organic and toxic solvents during production. Electrohydrodynamic processes, specifically electrospraying, could solve these challenges, as it also modulates antigen release and has a high loading efficiency. This review will highlight the mucosal immunity and biological basis of the gastrointestinal immune system, different oral vaccine delivery approaches, and the application of electrospraying in vaccines development.  相似文献   
12.
目前,国内外肝移植学界对肝移植术后急性排斥反应(AR)的机制阐释为T细胞介导的细胞免疫应答,但为获得长期生存仍需长期乃至终身服用免疫抑制剂。即使如此,临床上AR仍时有发生,并导致相当一部分受者移植肝功能丧失,更重要的是受者术后还受到感染、肿瘤和其他一系列不良反应及沉重经济负担的影响。因此,为肝移植AR机制提出新的理论解释,更全面深入阐明肝移植免疫排斥反应的内在机制,进而依据新的机制研制出新型免疫抑制剂已势在必行。本文就B细胞介导的体液免疫应答在肝移植AR中的作用作一综述。  相似文献   
13.
《Journal of thoracic oncology》2021,16(10):1694-1704
IntroductionIn patients with NSCLC, the prognostic significance of the tumor microenvironment (TME) immune composition has been revealed using single- or dual-marker staining on sequential tissue sections. Although these studies reveal that relative abundance and localization of immune cells are important parameters, deeper analyses of the NSCLC TME are necessary to refine the potential application of these findings to clinical care. Currently, the complex spatial relationships between cells of the NSCLC TME and potential drivers contributing to its immunologic composition remain unknown.MethodsWe used multispectral quantitative imaging on the lung adenocarcinoma TME in 153 patients with resected tumors. On a single slide per patient, we evaluated the TME with markers for CD3, CD8, CD14, CD19, major histocompatibility complex II (MHCII), cytokeratin, and 4′,6-diamidino-2-phenylindole (DAPI). Image analysis, including tissue segmentation, phenotyping, and spatial localization, was performed.ResultsSpecimens wherein greater than or equal to 5% of lung cancer cells expressed MHCII (MHCIIhi TME) had increased levels of CD4+ and CD8+ T cells and CD14+ cell infiltration. In the MHCIIhi TME, the immune infiltrate was closer to cancer cells and expressed an activated phenotype. Morphologic image analysis revealed cancer cells in the MHCIIhi TME more frequently interfaced with CD4+ and CD8+ T cells. Patients with an MHCIIhi TME experienced improved overall survival (p = 0.046).ConclusionsLung cancer cell-specific expression of MHCII associates with levels of immune cell infiltration, spatial localization, and activation status within the TME. This suggests that cancer cell-specific expression of MHCII may represent a biomarker for the immune system’s recognition and activation against the tumor.  相似文献   
14.
《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.  相似文献   
15.
16.
Since the clinical introduction of anti-CD20 monoclonal antibodies into lymphoma treatment, immunologic approaches in lymphoma have made substantial progress. Advances in our understanding of tumor immunology have led to the development of strategies to overcome immunologic barriers responsible for an ineffective immune response. Specifically, therapeutic agents have been developed and tested against molecules that are responsible for T-cell exhaustion. The use of monoclonal antibodies against immune checkpoints in the adaptive immune system, such as programmed cell death-1 and cytotoxic T-lymphocyte-associated protein 4, has changed the landscape of cancer therapy including the treatment of lymphoma. This achievement has recently been accompanied by the development of novel immune checkpoint inhibitors targeting the innate immune system, including the CD47-SIRPα signaling pathway, and this approach has yielded promising results. To overcome impaired antigen presentation, antibody-based cytotoxic strategies, namely antibody-drug conjugates (polatuzumab vedotin and brentuximab vedotin) and bispecific T-cell or NK-cell engagers (blinatumomab, REGN1979, RG6206, and AFM13), have rapidly evolved with promising clinical activity. As additional tools become available for lymphoma treatment, formulation of safe, rational combination strategies to combine them with standard therapy will be of paramount importance. A successful approach to the treatment of lymphoma may require both an optimized anti-tumor immune response as well as effective depletion of malignant lymphoid cells.  相似文献   
17.
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
18.
肝内胆管癌(ICC)可切除率低,进展期ICC的治疗有效率不高,预后很差。转化治疗在多种晚期肿瘤中有一定的疗效,是目前晚期肿瘤治疗的研究热点。随着对ICC基因组的深入了解和新的治疗药物的开发及组合,基于系统化疗的联合治疗策略,精准靶向治疗,免疫检查点抑制剂等显示出较好的疗效,使得部分进展期ICC病人能降期转化手术,获得长期生存。  相似文献   
19.
随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。  相似文献   
20.
目的 评价逐瘀止血汤加减对慢性子宫内膜炎(CE)气虚血瘀证患者妊娠结局的影响及对免疫炎症因子的调节作用。方法 将144例患者随机按数字表法分为观察组和对照组各72例。观察组脱落、失访4例,剔除2例,完成66例;对照组脱落、失访3例,剔除5例,完成65例。两组均给予抗感染治疗14 d。对照组口服妇科千金片,6片/次,3次/d。观察组内服逐瘀止血汤加减,1剂/d。两组疗程均为3个月,并随访6个月。记录治疗前后月经经量、经期和周期变化情况;进行治疗前后宫腔镜和阴道彩色多普勒超声检查,评价子宫内膜形态、子宫内膜容受性(CP)[子宫内膜厚度、阻力指数(RI),搏动指数(PI)和血流指数(FI)]等,并进行子宫内膜病理检查;进行治疗前后气虚血瘀证评分;检测治疗前后月经血白细胞介素-1β(IL-1β),IL-6和肿瘤坏死因子-α(TNF-α)水平和外周血测T淋巴亚群(CD3+,CD4+,CD8+)水平;随访记录妊娠情况和流产情况。进行安全性评价。结果 治疗后观察组经量、经期、周期和月经完全正常率均高于对照组(P<0.05);观察组子宫内膜厚度和FI均高于对照组(P<0.01),RI和PI均低于对照组(P<0.01);观察组月经血IL-1β,IL-6和TNF-α水平均低于对照组(P<0.01);观察组CD3+,CD4+水平和CD4+/ CD8+均高于对照组(P<0.01),CD8+水平低于对照组(P<0.01);在6个月随访期间,观察组妊娠率46.97%(31/66),高于对照组的27.69%(18/65)(χ2=5.197,P<0.05);观察组子宫内膜形态疗效总有效率为96.97%(64/66),高于对照组的86.15%(56/65)(χ2=4.981,P<0.05);观察组子宫内膜病理组织疗效总有效率为95.45%(63/66),高于对照组的84.62%(55/65)(χ2=4.304,P<0.05);观察组综合临床疗效总有效率为93.94%(62/66),高于对照组的81.54%(55/65)(χ2=4.696,P<0.05);两组治疗期间均未发现与中药相关不良反应。结论 逐瘀止血汤加减治疗CE气虚血瘀证患者,可调经月经、减轻临床症状,改善宫腔镜下内膜形态,调节全身和局部的免疫炎症反应,提高了CP,从而改善了妊娠结局,有着较好的综合疗效,且安全。  相似文献   
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