48 research outputs found

    β-Glucan Oligosaccharide Enhances CD8+ T Cells Immune Response Induced by a DNA Vaccine Encoding Hepatitis B Virus Core Antigen

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    DNA vaccination can induce specific CD8+ T cell immune response, but the response level is low in large mammals and human beings. Coadministration of an adjuvant can optimize protective immunity elicited by a DNA vaccine. In this study, we investigated the effect of a synthetic glucohexaose (β-glu6), an analogue of Lentinan basic unit, on specific CD8+ T cell response induced by a DNA vaccine encoding HBcAg (pB144) in mice. We found that β-glu6 promoted the recruitment and maturation of dendritic cells, enhanced the activation of CD8+ and CD4+ T cells and increased the number of specific CD8+/IFN-γ+ T cells in lymphoid and nonlymphoid tissues in mice immunized by pB144. Immunization with pB144 and β-glu6 increased the anti-HBc IgG and IgG2a antibody titer. These results demonstrate that β-glu6 can enhance the virus-specific CTL and Th1 responses induced by DNA vaccine, suggesting β-glu6 as a candidate adjuvant in DNA vaccination

    Circulating tumor DNA clearance predicts prognosis across treatment regimen in a large real-world longitudinally monitored advanced non-small cell lung cancer cohort

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    Background: Although growth advantage of certain clones would ultimately translate into a clinically visible disease progression, radiological imaging does not reflect clonal evolution at molecular level. Circulating tumor DNA (ctDNA), validated as a tool for mutation detection in lung cancer, could reflect dynamic molecular changes. We evaluated the utility of ctDNA as a predictive and a prognostic marker in disease monitoring of advanced non-small cell lung cancer (NSCLC) patients.Methods: This is a multicenter prospective cohort study. We performed capture-based ultra-deep sequencing on longitudinal plasma samples utilizing a panel consisting of 168 NSCLC-related genes on 949 advanced NSCLC patients with driver mutations to monitor treatment responses and disease progression. The correlations between ctDNA and progression-free survival (PFS)/overall survival (OS) were performed on 248 patients undergoing various treatments with the minimum of 2 ctDNA tests.Results: The results of this study revealed that higher ctDNA abundance (P=0.012) and mutation count (P=8.5x10(-4)) at baseline are associated with shorter OS. We also found that patients with ctDNA clearance, not just driver mutation clearance, at any point during the course of treatment were associated with longer PFS (P=2.2x10(-1)6, HR 0.28) and OS (P=4.5x10(-6), HR 0.19) regardless of type of treatment and evaluation schedule.Conclusions: This prospective real-world study shows that ctDNA clearance during treatment may serve as predictive and prognostic marker across a wide spectrum of treatment regimens

    Novel Loss-of-Function Variants in <i>CHD2</i> Cause Childhood-Onset Epileptic Encephalopathy in Chinese Patients

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    Developmental and epileptic encephalopathy-94 (DEE94) is a severe form of epilepsy characterized by a broad spectrum of neurodevelopmental disorders. It is caused by pathogenic CHD2 variants. While only a few pathogenic CHD2 variants have been reported with detailed clinical phenotypes, most of which lack molecular analysis. In this study, next-generation sequencing (NGS) was performed to identify likely pathogenic CHD2 variants in patients with epilepsy. Three likely pathogenic variants were finally identified in different patients. The seizure onset ages were from two years to six years. Patients 1 and 2 had developmental delays before epilepsy, while patient 3 had intellectual regression after the first seizure onset. The observed seizures were myoclonic, febrile, and generalized tonic-clonic, which had been controlled by different combinations of antiepileptic drugs. Two de novo (c.1809_1809+1delGGinsTT, p.? and c.3455+2_3455+3insTG, p.?) and one maternal (c.3783G>A, p.W1261*) variant were identified, which were all predicted to be pathogenic/likely pathogenic. Molecular analysis was performed in patient 1, and we detected aberrantly spliced products, proving the pathogenicity of this CHD2 variant. New cases with novel variants, along with a detailed clinical and molecular analysis, are important for a better understanding of CHD2-related epileptic encephalopathy

    ATP- binding cassette transporter A1 ( ABCA1) promotes arsenic tolerance in human cells by reducing cellular arsenic accumulation

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    Arsenic is a toxic element widely distributed in nature, such as water and soil. To survive this metalloid in the environment, nearly all organisms develop strategies to tolerate arsenic toxicity to some degree. Some arsenic-resistance genes have been identified in bacteria and yeast, but for mammals, especially humans, these genes are largely unknown. The aim of the present study was to identify these genes and benefit our intervention of arsenic resistance. We first established a human arsenic-resistant ECV-304 (AsRE) cell line and then used suppression subtractive hybridization and microarray analysis to identify arsenic-resistant genes in these cells. Of the significantly upregulated genes, three ATP-binding cassette (ABC) subfamily members, namely ABCA1, ABCE1 and ABCF1, were chosen for further study with RNA interference and overexpression analyses. The 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay was used to determine the cell survival rate and the IC, whereas atomic fluorescence spectrophotometry was used to determine intracellular arsenic levels. We found that among the three ABC genes, only when ABCA1 gene expression was silenced did cells obviously lose their arsenic tolerance. The arsenic accumulation in ABCA1 deficiency AsRE cells was greater than that in wild type AsRE cells. Overexpression of ABCA1 in HeLa cells decreased arsenic accumulation in the cells and the cells were more resistant to As(III) than control cells transfected with empty vector. These results suggest a new functional role for ABCA1 in the development of arsenic resistance in human cells

    Decreased Siglec-9 Expression on Natural Killer Cell Subset Associated With Persistent HBV Replication

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    Siglec-9 is an MHC-independent inhibitory receptor selectively expressed on CD56dim NK cells. Its role in infection diseases has not been investigated yet. Here, we studied the potential regulatory roles of NK Siglec-9 in the pathogenesis of chronic hepatitis B (CHB) infection. Flow cytometry evaluated the expression of Siglec-9 and other receptors on peripheral NK cells. Immunofluorescence staining was used to detect Siglec-9 ligands on liver biopsy tissues and cultured hepatocyte cell lines. Siglec-9 blocking assay was carried out and cytokine synthesis and CD107a degranulation was detected by flow cytometry. Compared to healthy donors, CHB patients had decreased Siglec-9+ NK cells, which reversely correlated with serum hepatitis B e antigen and HBV DNA titer. Siglec-9 expression on NK cells from patients achieving sustained virological response recovered to the level of normal donors. Neutralization of Siglec-9 restored cytokine synthesis and degranulation of NK cells from CHB patients. Immunofluorescence staining showed increased expression of Siglec-9 ligands in liver biopsy tissues from CHB patients and in hepatocyte cell lines infected with HBV or stimulated with inflammatory cytokines (IL-6 or TGF-β). These findings identify Siglec-9 as a negative regulator for NK cells contributing to HBV persistence and the intervention of Siglec-9 signaling might be of potentially translational significance

    Comparison of protective effects of nicotinamide mononucleotide and nicotinamide riboside on DNA damage induced by cisplatin in HeLa cells

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    Background: Previous studies have shown that the nicotinamide adenine dinucleotide (NAD+) precursors, nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR), protect against endogenously or exogenously induced DNA damage. However, whether the two compounds have the same or different efficacy against DNA damage is not clear. In the current study, we systematically compared the effects of NMN and NR on cisplatin-induced DNA damage in HeLa cells. Methods: To evaluate the protective effects of NMN or NR, HeLa cells were pretreated with different doses of NMN or NR followed with 10 μM of cisplatin treatment. Cell viability was examined by Trypan blue staining assay. For observing the DNA damage repair process, HeLa cells were treated with 10 μM of cisplatin for 12 h, followed with 10 mM NMN or NR treatment for another 8, 16, 24, or 32 h, DNA damage levels were assessed for each time point by immunofluorescent staining against phosphor-H2AX (γH2AX) and alkaline comet assay. The effects of NMN and NR on intracellular NAD+ and reactive oxygen species (ROS) levels were also determined. Results: NMN and NR treatment alone did not have any significant effects on cell viability, however, both can protect HeLa cells from cisplatin-induced decrease of cell viability with similar efficacy in a dose-dependent manner. On the other hand, while both can reduce the DNA damage levels in cisplatin-treated cells, NR exhibited better protective effect. However, both appeared to boost the DNA damage repair process with similar efficacy. NMN or NR treatment alone could increase cellular NAD+ levels, and both can reverse cisplatin-induced decrease of NAD+ levels. Finally, while neither NMN nor NR affected cellular ROS levels, both inhibited cisplatin-induced increase of ROS with no significant difference between them. Conclusion: NR have a better protective effect against cisplatin-induced DNA damage than NMN

    β-Glucan Oligosaccharide Enhances CD8 + T Cells Immune Response Induced by a DNA Vaccine Encoding Hepatitis B Virus Core Antigen

    No full text
    DNA vaccination can induce specific CD8 + T cell immune response, but the response level is low in large mammals and human beings. Coadministration of an adjuvant can optimize protective immunity elicited by a DNA vaccine. In this study, we investigated the effect of a synthetic glucohexaose (β-glu6), an analogue of Lentinan basic unit, on specific CD8 + T cell response induced by a DNA vaccine encoding HBcAg (pB144) in mice. We found that β-glu6 promoted the recruitment and maturation of dendritic cells, enhanced the activation of CD8 + and CD4 + T cells and increased the number of specific CD8 + /IFN-γ + T cells in lymphoid and nonlymphoid tissues in mice immunized by pB144. Immunization with pB144 and β-glu6 increased the anti-HBc IgG and IgG2a antibody titer. These results demonstrate that β-glu6 can enhance the virus-specific CTL and Th1 responses induced by DNA vaccine, suggesting β-glu6 as a candidate adjuvant in DNA vaccination
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