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Accurate and efficient antigen delivery is crucial for inducing a strong and long-term immune response. A visible protein nanovaccine made from antigen could provide a novel and promising technology for secure and efficient delivery of the antigen with imaging visualization. In this study, a functional nanovaccine based on genipin crosslinked ovalbumin (OVA) fluorescent nanoparticles with chitosan (CS-OVA-NPs) was developed. The nanovaccine can carry abundant antigens by self-crosslinking without additional carriers. The fluorescence imaging technique was applied to monitor and reveal the process of antigen delivery in vivo based on the fluorescence of genipin with a non-invasive and real-time manner. This functional OVA nanovaccine can enhance the uptake of OVA in Dendritic Cells (DCs) and further promote DCs to maturate in vitro. In vivo study further indicated CS-OVA-NPs could trigger antigen-specific immune responses, which demonstrated that this fluorescent nanovaccine provided a novel design approach for accurate and efficient vaccine delivery.  相似文献   
13.
Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice.  相似文献   
14.
Parkinson’s disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.  相似文献   
15.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
16.
The Cluster of differentiation 226(CD226)/T cell immunoglobulin and immune receptor tyrosine-based inhibitory motif domain (TIGIT) axis plays an important role in the balance of the immune response. A previous study showed that CD226 is involved in CD4+ T cell differentiation and that blocking CD226 may attenuate experimental autoimmune encephalomyelitis (EAE) development. However, the molecular mechanisms underlying this process remain incompletely understood. In this study, it was found that Cd226−/− mice were less susceptible to EAE and that there was less T helper 17(Th17) cell infiltration with higher levels of regulatory cells (Tregs) infiltration in the Cd226−/− EAE mouse central nervous system (CNS) compared with that in the WT EAE mouse CNS. Moreover, the suppressive function of Cd226−/− Tregs was upregulated compared with that of WT Tregs. Furthermore, it was observed that the expression levels of CTLA-4 and TIGIT on Cd226−/− Tregs were higher than those on WT Tregs during EAE in the spleen and CNS. Our results demonstrate a pivotal role for CD226 in attenuating Treg function in EAE that was associated with downregulating the expression levels of CTLA-4 and TIGIT.  相似文献   
17.
Medical Microbiology and Immunology - Gram-negative bacterium Legionella is able to proliferate intracellularly in mammalian host cells and amoeba, which became known in 1976 since they caused a...  相似文献   
18.
Liang  Xiongyan  Gu  Yufang  Chen  Xueyang  Li  Tuofan  Gao  Yulong  Wang  Xiaomei  Fang  Chun  Fang  Shouguo  Yang  Yuying 《Virus genes》2019,55(5):726-733
Virus Genes - Avian leukosis virus (ALV) caused tremendous economic losses to poultry industry all over the world, especially in China. One natural recombinant ALV strain, designated as HB2015032,...  相似文献   
19.
免疫球蛋白相关性疾病(immunoglobulin G4- related diseases,IgG4- RD)可累及全身各个器官,累及甲状腺者称为IgG4相关性甲状腺疾病(IgG4- related thyroid disease,IgG4- RTD)。其临床特点为受累器官弥漫性或局灶性肿大、硬化,血清IgG4升高。部分IgG4- RD可导致器官衰竭,特别是胰腺、肝脏和胆道、肾脏、甲状腺、肺和主动脉等。IgG4- RTD多表现为甲状腺局部结节或弥漫性肿大,多伴有血清IgG4升高。IgG4- RTD目前病因未明,多认为与遗传因素、病毒感染、抗原抗体反应有关,治疗上绝大多数对糖皮质激素治疗有效。本文概述了近年来IgG4相关性甲状腺疾病的研究进展。  相似文献   
20.
Zhang  Hui  Zhou  Xiu  Chen  Xin  Lin  Yuanzhen  Qiu  Shilin  Zhao  Yun  Tang  Qiya  Liang  Yi  Zhong  Xiaoning 《Inflammation research》2019,68(11):957-968
Inflammation Research - Chronic exposure to cigarette smoke promotes airway inflammation and emphysema accompanied by enhanced CD8+ interferon (IFN)-γ+ T(Tc1) and CD8+ interleukin (IL)-17+...  相似文献   
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