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121.
《Journal of hepatology》2020,72(5):924-936
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122.
目的探讨结核分枝杆菌DNA疫苗pcD85B、pcDMPT64以及小鼠白细胞介素12(IL-12)真核表达质粒psIL12对结核分枝杆菌感染的疗效与机制。方法将结核分枝杆菌H37Rv感染的C57BL/J6小鼠100只随机分成生理盐水对照组、pcDNA3.1对照组,psIL12治疗组,pcD85B、pcDMPT64、pcD85B+pcDMPT64、pcD85B+psIL12DNA疫苗治疗组。感染4周后分别给予生理盐水、空质粒、psIL-12及DNA疫苗,第1次治疗后2个月处死小鼠,检测器官荷菌量、脾淋巴细胞特异性γ干扰素(IFN-γ)、白细胞介素4(IL4)、肿瘤坏死因子-α(TNF-α)的分泌水平,并于第1次治疗后2个月、5个月观察小鼠肺、脾组织病理改变情况。结果pcD85B治疗组肺组织荷菌量(lg-1CFU/g)为6.99±0.40,比生理盐水对照组(8.15±0.37)、pCDNA3.1对照组(8.19±0.29)显著降低(P<0.01);脾组织荷菌量(lg-1CFU/g,x±s)为5.17±0.33,比生理盐水对照组(5.76±0.16)及空质粒对照组(5.88±0.21)显著降低(P<0.05)。psIL12治疗组的肺(7.41±0.50)、脾(5.31±0.21)荷菌量比对照组显著降低(P<0.05);pcD85B+psIL12治疗组肺、脾荷菌量与pcD85B组比较差别无统计学意义。pcD85B组脾淋巴细胞IFN-γ、TNFα水平比对照组显著升高(P<0.05),各组间IL4水平差异无统计学意义。生理盐水对照组、pCDNA3.1对照组肺组织  相似文献   
123.
Immunotherapy has recently become a powerful weapon against cancer. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) was the first immune checkpoint used for immunotherapy. However, CTLA-4-related mechanisms in various cancers have not been comprehensively investigated. This aim of this study was an in-depth investigation of CTLA-4 in the tumor microenvironment and its relationship with other immunomodulators, immune-related pathways and survival outcomes of 33 cancer types.Overall 9,743 tumor samples and 710 normal samples of 33 cancer types from The Cancer Genome Atlas (TCGA) database were included. CTLA-4 expression level was compared between tumor and normal tissues in 22 cancer types. The microenvironment cell populations (MCP)-counter method was used to analyze the correlation between CTLA-4 and immune cell infiltration. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were employed to investigate its relationship with immune pathways. Survival analysis was conducted using the Kaplan-Meier method with log-rank test.CTLA-4 expression was found to be increased in some types of cancer and decreased in other cancer types (P < 0.05). When comparing between different tumor tissues, CTLA-4 was lowest in uveal melanoma (UVM). MCP analysis demonstrated that CTLA-4 had a strong correlation with T cells in almost all cancer types and that CTLA-4 showed a positive correlation with most immune cells in UVM. Immune pathway analysis found that CTLA-4 is involved in a variety of immune pathways. Survival analysis revealed that CTLA-4 can predict patients’ survival outcomes. This comprehensive analysis of CTLA-4 will promote anti-CTLA-4 therapy and personalized combined immunotherapy.  相似文献   
124.
Heterologous expression of the functional amyloid beta (Aβ) antibody β1 in the central nervous system was engineered to maximize antibody exposure in the brain and assess the effects on Aβ production and accumulation in these conditions. A single open reading frame encoding the heavy and light chains of β1 linked by the mouth and foot virus peptide 2A was expressed in brain neurons of transgenic mice. Two of the resulting BIN66 transgenic lines were crossed with APP23 mice, which develop severe central amyloidosis. Brain concentrations at steady-state 5 times greater than those found after peripheral β1 administration were obtained. Similar brain and plasma β1 concentrations indicated robust antibody efflux from the brain. In preplaque mice, β1 formed a complex with Aβ that caused a modest Aβ increase in brain and plasma. At 11 months of age, β1 expression reduced amyloid by 97% compared with age-matched APP23 mice. Interference of β1 with β-secretase cleavage of amyloid precursor protein was relatively small. Our data suggest that severely impaired amyloid formation was primarily mediated by a complex of β1 with soluble Aβ, which might have prevented Aβ aggregation or favored transport out of the brain.  相似文献   
125.
Microbial contamination of grass pollens could affect sensitization, subsequent allergic response, and efficacy of allergen‐specific immunotherapy. We investigated whether bacterial immunomodulatory substances can direct PBMC responses of allergic and nonatopic subjects against ryegrass pollen (RGP) toward Th1, Th2, or regulatory T (Treg) cells. Aqueous extracts of RGP with high or low LPS were fractionated into large and small molecular weight (MW) components by diafiltration. CFSE‐labeled PBMCs from allergic and nonatopic subjects were stimulated with RGP extracts (RGPEs) and analyzed for cytokine secretion and T‐cell responses. High LPS RGPE increased IFN‐γ+ Th1 and IL‐4+ Th2 effector cell induction and consistently decreased CD4+Foxp3hi Treg‐cell induction. IL‐10‐producing T‐cell frequency was unaltered, but IL‐10 secretion was increased by high LPS RGPE. RGPE‐stimulation of TLR‐transfected cell lines revealed that high LPS pollen also contained a TLR2‐ligand, and both batches a TLR9‐ligand. Beta‐1,3‐glucans were detected in large and small MW fractions and were also T‐cell stimulatory. In conclusion, coexposure to allergen and proinflammatory microbial stimuli does not convert an established Th2‐ into a Th1‐response. Instead, proinflammatory responses are exacerbated and Foxp3hi Treg‐cell induction is decreased. These findings show that adjuvants for specific immunotherapy should enhance Treg cells rather than target immune deviation from Th2 to Th1.  相似文献   
126.
We aimed to induce three different immune cell subsets from a single blood sample from cancer patients to target different biological characters of cancer cells. In the presence of 6000 IU/ml IL-2, natural killer (NK) cells adhere to plastic. By using this ability, we could separate dendritic cells, T cells, and NK cells from peripheral blood mononuclear cells. The cultured NK cells demonstrated higher nonspecific cytotoxicity against tumor cell lines than did the T cells. Furthermore, adherent NK cells demonstrated higher cytotoxicity than nonadherent NK cells, although there was no difference between adherent and nonadherent NK cells in natural cytotoxicity receptors (NKp30, NKp44, NKp46) and NKG2D expression. With these results, we confirmed that we could induce dendritic cell, T cell, and higher cytotoxic NK cells from a single blood draw, and this methodology facilitates to the use of these cells for clinical grade conditions.  相似文献   
127.
Abstract

Objective: The aim of the present study was to evaluate the therapeutic potential of autologous DCs loaded with whole tumor cell lysate of CTVT generated under a simplified and rapid procedure in vitro production process, in a vulvar submucosal model of CTVT in dogs.

Materials and methods: We generated a model of intravulvar CTVT in dogs. A CTVT lysate antigen was prepared according to the method of 1-butanol and after administered with complete Freund's adjuvant via subcutaneous in female healthy dogs and challenge with CTVT cells to corroborate the immunogenicity. Short-time generated dendritic cell pulsed with CTVT whole-lysate was performed, and analyzed by FITC-dextran uptake assay and characterized using anti-canine monoclonal antibodies CD14, CD80, CD83, and DLAII by flow cytometry. Dendritic cell therapy was administered in a frequency of three times every 2 weeks when the CTVT had 4 months of growth and 89?±?5 cm diameter. The CD3+, CD4+ and CD8+ lymphocytes were determined by flow cytometry, and IFN-γ by ELISA assay.

Results and discussion: The administration of CTVT whole-lysate resulted in tumor prevention. The short-time generated dendritic cell pulsed with CTVT whole-lysate administration resulted in an efficient reduction and elimination of CTVT, probably due to the increase in lymphocyte populations (CD3+, CD4+, and CD8+), IFN-γ production and tumor infiltrating lymphocytes.

Conclusion: In conclusion, this study demonstrates the efficacy of immunotherapy based in short-time generated dendritic cell pulsed with CTVT whole-lysate for the treatment of CTVT, and offer veterinary oncologists new alternative therapies to treat this and another malignancy.  相似文献   
128.
Redirecting T cells by transferring T cell receptor (TCR) genes from tumor-associated antigen (TAA)-reactive T cell clones into human peripheral blood lymphocytes (PBL) has therapeutic potential for the treatment of diseases, including cancer. T cell specificity can be altered using retroviruses encoding TCR &#102 and TCR &#103 chain genes, or chimeric immunoglobulin (cIg) genes containing signaling domains of CD3 &#145 or Fc &#108 RI- &#110. This review evaluates recent studies using TCRs and cIgs to redirect T cell specificity and discusses some of the technical and biological hurdles that need to be addressed before these approaches can be successfully used to treat patients.  相似文献   
129.
Cytotoxic T-lymphocyte associated protein-4 (CTLA-4) and the Programmed Death Receptor 1 (PD-1) are immune checkpoint molecules that are well-established targets of antibody immunotherapies for the management of malignant melanoma. The monoclonal antibodies, Ipilimumab, Pembrolizumab, and Nivolumab, designed to interfere with T cell inhibitory signals to activate immune responses against tumors, were originally approved as monotherapy. Treatment with a combination of immune checkpoint inhibitors may improve outcomes compared to monotherapy in certain patient groups and these clinical benefits may be derived from unique immune mechanisms of action. However, treatment with checkpoint inhibitor combinations also present significant clinical challenges and increased rates of immune-related adverse events. In this review, we discuss the potential mechanisms attributed to single and combined checkpoint inhibitor immunotherapies and clinical experience with their use.  相似文献   
130.
This article reviews the preclinical research, clinical application and development of Newcastle disease virus (NDV) in the field of cancer therapy. Based on the distinctive antitumour properties of NDV and its positive interaction with the patient''s immune system, this biologic could be considered a major breakthrough in cancer treatment. On one hand, NDV infection creates an inflammatory environment in the tumour microenvironment, which can directly activate NK cells, monocytes, macrophages and dendritic cells and promote the recruitment of immune cells. On the other hand, NDV can induce the upregulation of immune checkpoint molecules, which may break immune tolerance and immune checkpoint blockade resistance. In fact, clinical data have shown that NDV combined with immune checkpoint blockade can effectively enhance the antitumour response, leading to the regression of local tumours and distant tumours when injected, and this effect is further enhanced by targeted manipulation and modification of the NDV genome. At present, recombinant NDV and recombinant NDV combined with immune checkpoint blockers have entered different stages of clinical trials. Based on these studies, further research on NDV is warranted.  相似文献   
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