33 results on '"Meng JX"'
Search Results
2. Amplicon-based metagenomic association analysis of gut microbiota in relation to egg-laying period and breeds of hens.
- Author
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Wang XY, Meng JX, Ren WX, Ma H, Liu G, Liu R, Geng HL, Zhao Q, Zhang XX, and Ni HB
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- Animals, Female, Chickens microbiology, RNA, Ribosomal, 16S genetics, Gastrointestinal Microbiome genetics, Microbiota, Cyanobacteria genetics
- Abstract
Background: The gut microbiota plays an essential role in maintaining gut homeostasis and improving performance, with the composition of microbial communities visibly differing across different laying stages in hens and significantly correlating with egg production. To gain further insights into the association between microbial community characteristics and laying periods in Hy-Line variety brown and Isa brown laying hens, we conducted a 16S rRNA amplicon sequencing survey., Results: Our result revealed the diversity of bacteria in the early laying period was commonly higher than peak, and in Hy-Line variety brown laying hens were generally higher than Isa brown. Principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA) revealed that the structure and composition of the gut microbiota of laying hens exhibited significant differences among different groups. Phylum Firmicutes, Bacteroidota, Proteobacteria, and Fusobacteriota were found that dominant in the host's feces. Therein, the abundance of Fusobacteriota was higher in the peak period than in the early period, while the abundance of Cyanobacteria in the early period was higher in two breeds of hens. Furthermore, random forest based on machine learning showed that there were several distinctly abundant genera, which can be used as potential biomarkers to differentiate the different groups of laying periods and breeds. In addition, the prediction of biological function indicated the existing discrepancy in microbial function among the microbiota of four groups., Conclusions: Our findings offer new insights into the bacterial diversity and intestinal flora composition of different strains of laying hens during various laying periods, contributing significantly to the improvement of production performance and the prevention of chicken diseases., (© 2023. The Author(s).)
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- 2023
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3. Anthocyanins from Malus spp. inhibit the activity of Gymnosporangium yamadae by downregulating the expression of WSC , RLM1 , and PMA1 .
- Author
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Wang Y, An H, Guo YN, Wang Q, Shang YY, Chen MK, Liu YX, Meng JX, Zhang SY, Wei J, and Li HH
- Abstract
Malus plants are frequently devastated by the apple rust caused by Gymnosporangium yamadae Miyabe. When rust occurs, most Malus spp. and cultivars produce yellow spots, which are more severe, whereas a few cultivars accumulate anthocyanins around rust spots, forming red spots that inhibit the expansion of the affected area and might confer rust resistance. Inoculation experiments showed that Malus spp. with red spots had a significantly lower rust severity. Compared with M. micromalus , M. 'Profusion', with red spots, accumulated more anthocyanins. Anthocyanins exhibited concentration-dependent antifungal activity against G. yamadae by inhibiting teliospores germination. Morphological observations and the leakage of teliospores intracellular contents evidenced that anthocyanins destroyed cell integrity. Transcriptome data of anthocyanins-treated teliospores showed that differentially expressed genes were enriched in cell wall and membrane metabolism-related pathways. Obvious cell atrophy in periodical cells and aeciospores was observed at the rust spots of M. 'Profusion'. Moreover, WSC , RLM1 , and PMA1 in the cell wall and membrane metabolic pathways were progressively downregulated with increasing anthocyanins content, both in the in vitro treatment and in Malus spp. Our results suggest that anthocyanins play an anti-rust role by downregulating the expression of WSC , RLM1 , and PMA1 to destroy the cell integrity of G. yamadae ., Competing Interests: The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, An, Guo, Wang, Shang, Chen, Liu, Meng, Zhang, Wei and Li.)
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- 2023
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4. Single-molecule dynamics of DNA gyrase in evolutionarily distant bacteria Mycobacterium tuberculosis and Escherichia coli.
- Author
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Galvin CJ, Hobson M, Meng JX, Ierokomos A, Ivanov IE, Berger JM, and Bryant Z
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- Adenosine Triphosphate metabolism, DNA, DNA, Superhelical, Molecular Dynamics Simulation, DNA Gyrase chemistry, DNA Gyrase metabolism, Escherichia coli enzymology, Escherichia coli metabolism, Mycobacterium tuberculosis enzymology, Mycobacterium tuberculosis metabolism
- Abstract
DNA gyrase is an essential nucleoprotein motor present in all bacteria and is a major target for antibiotic treatment of Mycobacterium tuberculosis (MTB) infection. Gyrase hydrolyzes ATP to add negative supercoils to DNA using a strand passage mechanism that has been investigated using biophysical and biochemical approaches. To analyze the dynamics of substeps leading to strand passage, single-molecule rotor bead tracking (RBT) has been used previously to follow real-time supercoiling and conformational transitions in Escherichia coli (EC) gyrase. However, RBT has not yet been applied to gyrase from other pathogenically relevant bacteria, and it is not known whether substeps are conserved across evolutionarily distant species. Here, we compare gyrase supercoiling dynamics between two evolutionarily distant bacterial species, MTB and EC. We used RBT to measure supercoiling rates, processivities, and the geometries and transition kinetics of conformational states of purified gyrase proteins in complex with DNA. Our results show that E. coli and MTB gyrases are both processive, with the MTB enzyme displaying velocities ∼5.5× slower than the EC enzyme. Compared with EC gyrase, MTB gyrase also more readily populates an intermediate state with DNA chirally wrapped around the enzyme, in both the presence and absence of ATP. Our substep measurements reveal common features in conformational states of EC and MTB gyrases interacting with DNA but also suggest differences in populations and transition rates that may reflect distinct cellular needs between these two species., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2023
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5. Metagenomic insights into the composition and function of the gut microbiota of mice infected with Toxoplasma gondii .
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Meng JX, Wei XY, Guo H, Chen Y, Wang W, Geng HL, Yang X, Jiang J, and Zhang XX
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- Animals, Mice, Persistent Infection, Dysbiosis, Inflammation, Toxoplasma, Gastrointestinal Microbiome, Toxoplasmosis
- Abstract
Introduction: Despite Toxoplasma gondii infection leading to dysbiosis and enteritis, the function of gut microbiota in toxoplasmosis has not been explored., Methods: Here, shotgun metagenomics was employed to characterize the composition and function of mouse microbial community during acute and chronic T. gondii infection, respectively., Results: The results revealed that the diversity of gut bacteria was decreased immediately after T. gondii infection, and was increased with the duration of infection. In addition, T. gondii infection led to gut microbiota dysbiosis both in acute and chronic infection periods. Therein, several signatures, including depression of Firmicutes to Bacteroidetes ratio and infection-enriched Proteobacteria, were observed in the chronic period, which may contribute to aggravated gut inflammation and disease severity. Functional analysis showed that a large amount of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and carbohydrate-active enzymes (CAZy) family displayed distinct variation in abundance between infected and healthy mice. The lipopolysaccharide biosynthesis related pathways were activated in the chronic infection period, which might lead to immune system imbalance and involve in intestinal inflammation. Moreover, microbial and functional spectrums were more disordered in chronic than acute infection periods, thus implying gut microbiota was more likely to participate in disease process in the chronically infected mice, even exacerbated immunologic derangement and disease progression., Discussion: Our data indicate that the gut microbiota plays a potentially important role in protecting mice from T. gondii infection, and contributes to better understand the association between gut microbiota and toxoplasmosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Meng, Wei, Guo, Chen, Wang, Geng, Yang, Jiang and Zhang.)
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- 2023
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6. Description of Gut Mycobiota Composition and Diversity of Caprinae Animals.
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Lv QB, Meng JX, Ma H, Liu R, Qin Y, Qin YF, Geng HL, Ni HB, and Zhang XX
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- Animals, Fungi genetics, China, Gastrointestinal Microbiome, Basidiomycota, Ascomycota genetics, Mycobiome
- Abstract
The fungal community, also known as mycobiota, plays pivotal roles in host nutrition and metabolism and has potential to cause disease. However, knowledge of the gut fungal structure in Caprinae is quite limited. In this study, the composition and diversity of the gut mycobiota of Caprinae animals from different geographical locations (Anhui, Jilin, Guangxi, Shandong, Shanxi, and Tibet) were comprehensively characterized by analyzing the internal transcribed spacer 2 (ITS-2) sequences of the fungal community. The results showed that Ascomycota and Basidiomycota were the dominant phyla, which, respectively, accounted for 90.86 to 95.27% and 2.58 to 7.62% of sequences in samples from each region. Nonetheless, the structure of the gut mycobiota was largely different in Caprinae animals in the different provinces. Therein, Sporormiaceae and Thelebolaceae were the dominant fungal families in the samples from Tibet, whereas their abundance was generally low in other regions. The intestinal diversity of individuals from Guangxi was higher than that in other regions. In addition, there were 114 differential genera among all regions. Finally, the co-occurrence network revealed 285 significant correlations in cross-family pairs in the guts of Caprinae animals, which contained 149 positive and 136 negative relationships, with 96 bacterial and 86 fungal participants at the family level. This study has improved the understanding of the mycobiota of ruminants and provided support for the improvement in animal health and productivity. IMPORTANCE In this study, we elucidated and analyzed the structure of the gut mycobiota of Caprinae animals from different regions. This study revealed differences in the structure of the gut mycobiota among Caprinae animals from different geographical environments. Based on previous findings, correlations between fungal and bacterial communities were analyzed. This study adds to previous research that has expanded the present understanding of the gut microbiome of Caprinae animals.
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- 2023
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7. A Catalog of over 5,000 Metagenome-Assembled Microbial Genomes from the Caprinae Gut Microbiota.
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Zhang XX, Lv QB, Yan QL, Zhang Y, Guo RC, Meng JX, Ma H, Qin SY, Zhu QH, Li CQ, Liu R, Liu G, Li SH, Sun DB, and Ni HB
- Subjects
- Sheep, Animals, Bacteria genetics, Bacteria metabolism, Genome, Bacterial, Metagenomics, Genome, Microbial, Ruminants, Metagenome, Gastrointestinal Microbiome genetics
- Abstract
Most microbiome studies regarding the ruminant digestive tract have focused on the rumen microbiota, whereas only a few studies were performed on investigating the gut microbiota of ruminants, which limits our understanding of this important component. Herein, the gut microbiota of 30 Caprinae animals (sheep and goats) from six provinces in China was characterized using ultradeep (>100 Gbp per sample) metagenome shotgun sequencing. An inventory of Caprinae gut microbial species containing 5,046 metagenomic assembly genomes (MAGs) was constructed. Particularly, 2,530 of the genomes belonged to uncultured candidate species. These genomes largely expanded the genomic repository of the current microbes in the Caprinae gut. Several enzymes and biosynthetic gene clusters encoded by these Caprinae gut species were identified. In summary, our study extends the gut microbiota characteristics of Caprinae and provides a basis for future studies on animal production and animal health. IMPORTANCE We constructed a microbiota catalog containing 5,046 MAGs from Caprinae gut from six regions of China. Most of the MAGs do not overlap known databases and appear to be potentially new species. We also characterized the functional spectrum of these MAGs and analyzed the differences between different regions. Our study enriches the understanding of taxonomic, functional, and metabolic diversity of Caprinae gut microbiota. We are confident that the manuscript will be of utmost interest to a wide range of readers and be widely applied in future research.
- Published
- 2022
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8. CircRNA and miRNA expression analysis in livers of mice with Toxoplasma gondii infection.
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Zou Y, Meng JX, Wei XY, Gu XY, Chen C, Geng HL, Yang LH, Zhang XX, and Cao HW
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- Mice, Animals, RNA, Circular, Liver metabolism, Transcriptome, MicroRNAs genetics, MicroRNAs metabolism, Toxoplasmosis genetics, Toxoplasma genetics
- Abstract
Toxoplasmosis is an important zoonotic parasitic disease caused by Toxoplasma gondii ( T. gondii ). However, the functions of circRNAs and miRNAs in response to T. gondii infection in the livers of mice at acute and chronic stages remain unknown. Here, high-throughput RNA sequencing was performed for detecting the expression of circRNAs and miRNAs in livers of mice infected with 20 T. gondii cysts at the acute and chronic stages, in order to understand the potential molecular mechanisms underlying hepatic toxoplasmosis. Overall, 265 and 97 differentially expressed (DE) circRNAs were found in livers at the acute and chronic infection stages in comparison with controls, respectively. In addition, 171 and 77 DEmiRNAs were found in livers at the acute and chronic infection stages, respectively. Functional annotation showed that some immunity-related Gene ontology terms, such as "positive regulation of cytokine production", "regulation of T cell activation", and "immune receptor activity", were enriched at the two infection stages. Moreover, the pathways "Valine, leucine, and isoleucine degradation", "Fatty acid metabolism", and "Glycine, serine, and threonine metabolism" were involved in liver disease. Remarkably, DEcircRNA 6:124519352|124575359 was significantly correlated with DEmiRNAs mmu-miR-146a-5p and mmu-miR-150-5p in the network that was associated with liver immunity and pathogenesis of disease. This study revealed that the expression profiling of circRNAs in the livers was changed after T. gondii infection, and improved our understanding of the transcriptomic landscape of hepatic toxoplasmosis in mice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zou, Meng, Wei, Gu, Chen, Geng, Yang, Zhang and Cao.)
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- 2022
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9. Dynamic description of temporal changes of gut microbiota in broilers.
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Li MH, Meng JX, Wang W, He M, Zhao ZY, Ma N, Lv QB, Qin YF, Geng HL, Zhao Q, Ni HB, and Zhang XX
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- Animals, Bacteria genetics, Chickens, Fungi, RNA, Ribosomal, 16S, Gastrointestinal Microbiome, Microbiota
- Abstract
The diversity of bacteria and fungi in the gut microbiota of commercial broilers that raised in cages from hatch to the end of the production cycle were examined by an analysis of 3,592 and 3,899 amplicon sequence variants (ASVs), respectively. More than 90% sequences in bacterial communities were related to Firmicutes and Proteobacteria. More than 90% sequences in fungal communities were related to Ascomycota, Basidiomycota, and Glomeromycota. A statistical analysis of the microbiota composition succession showed that age was one of the main factors affecting the intestinal microbial communities of broilers. The increasingly complex community succession of transient microbiota occurred along with an increase of age. This dynamic change was observed to be similar between bacteria and fungi. The gut microbiota had a special structure in the first 3 d after birth of broiler. The microbiota structure was quite stable in the period of rapid skeletal growth (d 14-21), and then changed significantly in the period of rapid gaining weight (d 35-42), thus indicating the composition of gut microbiota in broilers had unique structures at different developmental stages. We observed that several bacteria and fungi occupied key functions in the gut microbiota of broilers, suggesting that the gut homeostasis of broilers might be affected by losses of bacteria and fungi via altering interactions between microbiota. This study aimed to provide a data basis for manipulating the microbiota at different developmental stages, in order to improve production and the intestinal health of broilers., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2022
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10. Hyperphosphorylated tau self-assembles into amorphous aggregates eliciting TLR4-dependent responses.
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Meng JX, Zhang Y, Saman D, Haider AM, De S, Sang JC, Brown K, Jiang K, Humphrey J, Julian L, Hidari E, Lee SF, Balmus G, Floto RA, Bryant CE, Benesch JLP, Ye Y, and Klenerman D
- Subjects
- Glycogen Synthase Kinase 3 beta metabolism, Heparin, Humans, Phosphorylation, Protein Aggregation, Pathological metabolism, Protein Isoforms metabolism, Tauopathies metabolism, Toll-Like Receptor 4 metabolism, tau Proteins metabolism, tau Proteins ultrastructure
- Abstract
Soluble aggregates of the microtubule-associated protein tau have been challenging to assemble and characterize, despite their important role in the development of tauopathies. We found that sequential hyperphosphorylation by protein kinase A in conjugation with either glycogen synthase kinase 3β or stress activated protein kinase 4 enabled recombinant wild-type tau of isoform 0N4R to spontaneously polymerize into small amorphous aggregates in vitro. We employed tandem mass spectrometry to determine the phosphorylation sites, high-resolution native mass spectrometry to measure the degree of phosphorylation, and super-resolution microscopy and electron microscopy to characterize the morphology of aggregates formed. Functionally, compared with the unmodified aggregates, which require heparin induction to assemble, these self-assembled hyperphosphorylated tau aggregates more efficiently disrupt membrane bilayers and induce Toll-like receptor 4-dependent responses in human macrophages. Together, our results demonstrate that hyperphosphorylated tau aggregates are potentially damaging to cells, suggesting a mechanism for how hyperphosphorylation could drive neuroinflammation in tauopathies., (© 2022. The Author(s).)
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- 2022
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11. MrMYB44-Like Negatively Regulates Anthocyanin Biosynthesis and Causes Spring Leaf Color of Malus 'Radiant' to Fade From Red to Green.
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Meng JX, Wei J, Chi RF, Qiao YH, Zhou J, Wang YL, Wang H, and Li HH
- Abstract
The "Spring-red-leaf" crabapple cultivar has young red leaves and mature green leaves. However, the mechanism of anthocyanin biosynthesis in crabapple leaves in spring remains unknown. In this study, Illumina RNA sequencing (RNA-Seq) was performed on Malus 'Radiant' leaf tissues in different stages of development. Twenty-two genes in the anthocyanin biosynthesis pathway and 44 MYB transcription factors (TFs) were significantly enriched among differentially expressed genes (DEGs). Three R2R3-MYB TFs in subgroup 22 of the MYB TF family, MrMYB44-like1 , MrMYB44-like2 , and MrMYB44-like3 , were highly expressed in green leaves according to RNA-Seq and quantitative real-time quantitative PCR results. Their expression levels were negatively correlated with anthocyanin content. In transient assays, overexpression of MrMYB44-like1 , MrMYB44-like2 , or MrMYB44-like3 inhibited anthocyanin accumulation and reduced pigment in leaf disks of M . 'Radiant' and fruit peels of M. domestica 'Fuji.' When the conserved region of the three MrMYB44-like s was silenced, the anthocyanin biosynthesis pathway was activated and pigments increased in both tissues. Moreover, bimolecular fluorescence complementation assays showed MrMYB44-like s interacted with MrWRKY6 to form protein complexes that regulated anthocyanin biosynthesis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Meng, Wei, Chi, Qiao, Zhou, Wang, Wang and Li.)
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- 2022
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12. The complete chloroplast genome of Casuarina cunninghamiana (Casuarinaceae).
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Li Z, Zhang Y, Wei YC, Meng JX, and Wang YJ
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Casuarina cunninghamiana Miq. naturally occurs in eastern Australia from New South Wales to north Queensland. After being introduced to China, it has become an important tree species of ecological shelter plantations in coastal areas of southern China. In this study, the complete chloroplast (cp) genome of C. cunninghamiana was sequenced and analyzed based on the Illumina NovaSeq 6000 platform. The cp genome of C. cunninghamiana was found to be 15,6129 bp in length, including a large single copy (LSC) region of 86,200 bp and a small single copy (SSC) region of 18,457 bp, which were separated by two inverted repeats (IRs) of 25,736 bp. The cp genome contains 132 genes, consisting of 87 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The overall GC content of the cp genome was 36.34%. The phylogenetic analyses indicated that C. cunninghamiana was closely related to C. glauca and C. equisetifolia and clustered with 4 Betulaceae species., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)
- Published
- 2021
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13. [In vitro studies on the transfer of CAR into leukemia cells due to their residue in the autologous CAR-T cell preparation system for acute B-cell acute lymphoblastic leukemia].
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Liu MJ, Mu J, Yuan T, Cui R, Meng JX, Jiang YY, Li YM, and Deng Q
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- Antigens, CD19, B-Lymphocytes, Humans, Immunotherapy, Adoptive, Leukocytes, Mononuclear, T-Lymphocytes, Precursor Cell Lymphoblastic Leukemia-Lymphoma, Receptors, Chimeric Antigen
- Abstract
Objective: To investigate the characteristics and cytotoxicity in vitro of the residual leukemia cells in the culture system that caused the accidental transfer of CD19 chimeric antigen receptor (CAR) into leukemia cells during the preparation of autologous CD19 CAR-T cells of relapsed/refractory B-cell acute lymphoblastic leukemia. Methods: ①Peripheral blood mononuclear cells (PBMC) of 30 patients with relapsed/refractory B-cell acute lymphoblastic anemia (R/R B-ALL) who accepted CD19 CAR-T cell therapy and six healthy volunteers were collected. ②The residual leukemia cells were analyzed by flow cytometry in the system after the PBMCs of R/R B-ALL patients were sorted by CD3 magnetic beads. ③ CD3(+) T cells from patients and healthy volunteers were transfected with CD19 CAR and CD22 CAR lentivirus to prepare CD19 CAR-T and CD22 CAR-T cells. ④The Nalm-6 cell line was resuscitated and the Nalm-6 cells with CD19 CAR lentivirus were transfected to prepare CD19 CAR-Nalm-6 cells. The patient's primary ALL cells were transfected with CD19 CAR lentivirus at the same time. ⑤The transfection rates were analyzed by flow cytometer, the cell proliferation was analyzed by the CCK-8 method, and the cell-killing activities were detected by the lactate dehydrogenase method. Results: ① Among the 30 R/R B-ALL patients who received CD19 CAR-T cell therapy, two patients had 2.04% and 3.32% residual leukemia cells in CD3(+) T cells. After 4 days in culture, the residual leukemia cells disappeared and could not be detected by a flow cytometer with prolonged cultivation in vitro. ② The proliferation of CD19 CAR-Nalm-6 cells was higher than that of the Nalm-6 cells. ③ The killing activity of the CD19 CAR-T cells on Nalm-6 cells was higher than that of the CD19 CAR-Nalm6 cells at a target ratio of 1∶1 on 24, 48, 72 h, respectively. The cytotoxicity of CD22 CAR-T cells on CD19 CAR-Nalm-6 cells was significantly higher than that of CD19 CAR-T cells. ④ The cytotoxicity of CD22 CAR-T alone on CD19 CAR-Nalm-6 cells was higher than that of CD19 CAR-T combined with CD22 CAR-T at the same target ratio. Conclusion: The residual leukemia cells in the culture system in the preparation of CD19 CAR-T cells may lead to the introduction of CD19 CAR into leukemia cells and results in the failure of the CD19 CAR-T cell therapy. Detecting the residual leukemia cells in the culture system via flow cytometry before transfection with CD19 CAR lentivirus is needed. Thus, CD22 CAR-T cell therapy could be used as one of the salvage treatments.
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- 2021
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14. How the Color Fades From Malus halliana Flowers: Transcriptome Sequencing and DNA Methylation Analysis.
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Han ML, Yin J, Zhao YH, Sun XW, Meng JX, Zhou J, Shen T, Li HH, and Zhang F
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The flower color of many horticultural plants fades from red to white during the development stages, affecting ornamental value. We selected Malus halliana , a popular ornamental species, and analyzed the mechanisms of flower color fading using RNA sequencing. Forty-seven genes related to anthocyanin biosynthesis and two genes related to anthocyanin transport were identified; the expression of most of these genes declined dramatically with flower color fading, consistent with the change in the anthocyanin content. A number of transcription factors that might participate in anthocyanin biosynthesis were selected and analyzed. A phylogenetic tree was used to identify the key transcription factor. Using this approach, we identified MhMYB10 as directly regulating anthocyanin biosynthesis. MhMYB10 expression was strongly downregulated during flower development and was significantly positively related to the expression of anthocyanin biosynthetic genes and anthocyanin content in diverse varieties of Malus . To analyze the methylation level during flower development, the MhMYB10 promoter sequence was divided into 12 regions. The methylation levels of the R2 and R8 increased significantly as flower color faded and were inversely related to MhMYB10 expression and anthocyanin content. Therefore, we deduce that the increasing methylation activities of these two regions repressed MhMYB10 expression., (Copyright © 2020 Han, Yin, Zhao, Sun, Meng, Zhou, Shen, Li and Zhang.)
- Published
- 2020
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15. [Analysis on poor efficacy factors in the treatment of recurrent/refractory B-cell lymphoma with CD19 CAR-T cells].
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Xiao X, Yuan T, Meng JX, Jiang YY, Cao YQ, Li Q, Sun R, and Zhao MF
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- Antigens, CD19, Humans, Immunotherapy, Adoptive, T-Lymphocytes, Lymphoma, B-Cell, Neoplasm Recurrence, Local
- Abstract
Objective: To investigate the factors influencing the efficacy of CD19 chimeric antigen receptor T (CAR-T) cells in the treatment of patients with relapsed refractory B cell lymphoma and to provide evidence for further improvement of CAR-T efficacy. Methods: A total of 34 patients with relapsed and refractory B-cell lymphoma were recruited from the Department of Hematology of Tianjin First Central Hospital from February 2017 to January 2019. All patients received CD19 CAR-T cell therapy. These patients were evaluated for efficacy, factors with poor efficacyand adverse effects. Results: The overall response rate was 58.8% (20/34) and the complete remission rate was 41.2% (14/34) after infusion of CD19 CAR-T cells in 34 patients with relapsed refractory B cell lymphoma. According to the efficacy of CAR-T cells, patients were divided into two groups, 20 in the effective group and 14 in the poorly effective group. The median am ount of CD19 CAR-T cell infusions in these two groups were 8.6 (5.0-12.7)×10(6)/kg and 9.7 (5.8-15.0) × 10(6)/kg, respectively, and the difference was not statistically significant ( P= 0.654). The percentage of CD19 CAR-T cells in the effective group and the poorly treated group was 10.28% (3.92%-44.16%) and 4.05% (0.92%-28.63%), respectively.The effective group had a higher proportion of CAR-T cells than the poorly treated group, but the difference was not statistically significant ( P= 0.371).The presence of massive mass was an unfavorable factor affecting the efficacy of CD19 CAR-T cells and the difference was statistically significant ( P= 0.001). Logistic regression multivariate analysis showed that the characteristics of massive tumors were still independent prognostic factors for poor efficacy of CD19 CAR-T cells ( P= 0.005, OR= 0.039). Of all 34 patients, there were 70.6% (24/34) who showed varying degrees of adverse reactions after the infusion of CD19 CAR-T cells, mainly cytokines release syndrome (CRS). The median time of occurrence of fever was on the third day after infusion (0-11th) day. 16 patients were with grade 1 CRS, 7 with grade 2, and 1 with grade 3. After glucocorticoids and support treatment, they all showed improvements. Conclusions: CD19 CAR-T cell therapy has achieved a certain effect in CD19(+)B cell lymphoma, but has poor efficacy on some patients. Large mass tumors may be an adverse factors to CAR-T cell treatment.
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- 2020
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16. CAR-T 19 combined with reduced-dose PD-1 blockade therapy for treatment of refractory follicular lymphoma: A case report.
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Wang J, Deng Q, Jiang YY, Zhang R, Zhu HB, Meng JX, and Li YM
- Abstract
Anti-CD19 chimeric antigen receptor T cell (CAR-T) therapy has changed the typical outcomes of relapsed/refractory B-cell leukemia and lymphoma. However, treatment effectiveness for patients with relapsed/refractory B-cell non-Hodgkin lymphoma has been less satisfactory compared with patients with B-cell acute lymphoblastic leukemia. The present study described a case of refractory follicular lymphoma. A high expression of programmed cell death 1 (PD-1) was measured on CD3
+ T cells (80.90%) in peripheral blood samples obtained from the patient enrolled in this study, indicating that treatment with autologous CAR-T 19 cell therapy may not be successful. Therefore, a therapy regimen consisting of CAR-T 19 cells in combination with a reduced dose of nivolumab (1.5 mg/kg) for PD-1 blockade was used. A low dose of PD-1 blockade therapy was used to reduce the adverse effects associated with the combination of a PD-1 inhibitor and CAR-T 19 cells. This salvage therapy resulted in remission that lasted for >10 months., (Copyright: © Wang et al.)- Published
- 2019
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17. [PD-1 expression, mRNA level and cytotoxicity changes in CD19CAR-T cells].
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Pu YD, Wang J, Deng Q, Zhu HB, Jiang YY, Meng JX, and Li YM
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- Antigens, CD19, Humans, RNA, Messenger, Receptors, Antigen, T-Cell, Programmed Cell Death 1 Receptor genetics, T-Lymphocytes
- Abstract
Objective: To observe the changes of PD-1 expression, mRNA level and cytotoxic activity of CD19 CAR-T cells during the culture process of CAR-T cells. Methods: The peripheral blood T cells of 6 lymphoma patients with high expression of PD-1 and 6 healthy volunteers were the source of CAR-T cells. The expression of PD-1 was analyzed by flow cytometry. The mRNA level of PD-1 was analyzed by PCR. The cell proliferation was analyzed by CCK-8 assay. The cytotoxicity was analyzed by LDH assay. Results: ①The transfection efficiency of high PD-1 expression T cells and healthy volunteer T cells were as the same ( P >0.05) . ②The cell proliferation capacity of CD19 CAR-T cells from high PD-1 expression T cells or healthy volunteer T cells, with or without PD-1 inhibitor were as the same ( P >0.05) . ③The cytotoxicity to lymphoma cells of high PD-1 expression T cells and CAR-T cells were lower than that of these two T cells combined with PD-1 inhibitor and the CAR-T cells from healthy volunteer T cells ( P <0.001) . There was no difference of the cytotoxicity between the CAR-T cells from high PD-1 expression T cells combined with PD-1 inhibitor and the CAR-T cells from healthy volunteer ( P >0.05) . ④There was no difference of the expression of PD-1 in all CAR-T cell groups during the culture process ( P >0.05) . There was no difference of mRNA level of PD-1 in all groups during the culture process ( P >0.05) . ⑤The PD-1 expression of CAR-T cells increased by the time of culture after contacting with lymphoma cells ( P <0.001) . The PD-1 inhibitors could antagonize this effect. There was no difference of mRNA level of PD-1 in all groups after contacting with lymphoma cells ( P >0.05) . Conclusion: The PD-1 expression of CAR-T cells from high PD-1 expression T cells increased by the time of culture after contacting with lymphoma cells. However, the mRNA level of PD-1 of all groups did not change, even if PD-1 inhibitor was applied.
- Published
- 2019
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18. [Efficacy and safety of CD19 chimeric antigen receptor T cells for the treatment of 22 patients with B-cell lymphoma].
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Xiao X, Jiang YY, Cao YQ, Li Q, Jin X, Meng JX, Sui T, Li YM, and Zhao MF
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- Antigens, CD19, Humans, Neoplasm Recurrence, Local, Receptors, Antigen, T-Cell, Receptors, Chimeric Antigen, T-Lymphocytes, Lymphoma, B-Cell
- Abstract
Objective: To investigate the efficacy and safety of CD19 chimeric antigen receptor T (CAR-T) lymphocytes for the treatment of B cell lymphoma. Methods: A total of 22 patients with B-cell lymphoma from February 1, 2017 to July 1, 2018 were reviewed to evaluate the efficacy and adverse reactions of CD19 CAR-T. Results: Of 22 patients with B-cell lymphoma received CD19 CAR-T cells, the median dose of CAR-T cells was 7.2 (2.0-12.0) ×10
6 /kg. Nine of 12 cases of relapse refractory patients were overall response. Complete remission (CR) occurred in 2 of 12 patients, partial remission (PR) in 7 of 12 patients. The overall response in minor residual disease positive (MRD) group was 8 of 10 patients. CD19 CAR-T cells proliferated in vivo and were detectable in the blood of patients. The peak timepoints of CAR-T cells proliferated in the relapsed refractory and MRD positive groups were 12 (5-19) and 4.5 (1-12) days after treatment respectively, and among peripheral blood cells, CAR-T cells accounted for 10.10% (3.55%-24.74%) and 4.02% (2.23%-28.60%) of T lymphocytes respectively. The MRD positive patients achieved sustained remissions during a median follow-up of 8 months (rang 3-18 months) . None of all the patients relapsed during a median follow-up time of 10 months (3-18 months) . However, 7 PR responders of the relapsed refractory patients maintained a good condition for 1.5-6.0 months. One patient bridged to hematopoietic stem cell transplantation, another one sustained remission for 12 months. Cytokine-release syndrome (CRS) occurred in 14 patients with grade 1-2 CRS in MRD positive group and grade 3 CRS in relapsed refractory group. Conclusions: CAR-T cell therapy not only played a role in the rescue treatment of relapsed and refractory patients, but also produced a surprising effect in the consolidation and maintenance of B-cell lymphoma. CD19 CAR-T cells might be more effective in the treatment of MRD positive B-cell lymphoma patients than in the refractory or relapsed cases. High response rate was observed with fewer adverse reactions.- Published
- 2019
- Full Text
- View/download PDF
19. [Efficacy and safety of reduced dose of PD-1 inhibitor combined with CD19-CAR-T on B-cell non-Hodgkin lymphoma patients with high expression of PD-1 in peripheral blood].
- Author
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Wang J, Deng Q, Jiang YY, Zhang R, Zhu HB, Meng JX, Zhao MF, and Li YM
- Published
- 2018
- Full Text
- View/download PDF
20. [Effect of PD-1 inhibitor Nivolumab on the proliferation and cytotoxicity of anti-CD19 chimeric antigen receptor T cells].
- Author
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Zhu HB, Deng Q, Zhang R, Jiang YY, Meng JX, Zhao MF, Li YM, and Cui R
- Subjects
- Antigens, CD19, Cell Proliferation, Humans, Leukocytes, Mononuclear, Programmed Cell Death 1 Receptor, Receptors, Antigen, T-Cell, Receptors, Chimeric Antigen, T-Lymphocytes, Nivolumab pharmacology
- Abstract
Objective: To Evaluation the effect of PD-1 inhibitor Nivolumab on the proliferation and cytotoxicity of anti-CD19 chimeric antigen receptor T cells (CD19-CAR-T) in vitro . Methods: Five patients with high PD-1 expression in peripheral blood and five healthy volunteers were selected. These peripheral blood mononuclear cells were used as the source of T cells to prepare CD19-CAR-T cells. Different doses (72, 36, 18 μg/ml) of Nivolumab was added on day 8 to the culture medium. Patient T cells incubated with 72 μg/ml Nivolumab and CD19-CAR-T cells of healthy volunteers were used as controls. CCK-8, lactate dehydrogenase (LDH) cytotoxicity assay and ELASA were used to detect the proliferation capacity, the specific cytotoxicity and the inflammatory factor secretion. Results: ①T cells from patients with high expression of PD-1 as the source of CD19-CAR-T cells did not affect transfection rate compared with that of healthy volunteers [(32.80±7.22)% vs (35.10±5.84)%, t =-0.554, P =0.593]. ②Incubation of CD19-CAR-T cells with 72 μg/ml Nivolumab did not affect CD19-CAR-T cell proliferation, but its cytotoxicity was significantly higher than that of CD19-CAR-T cells alone or patients' T cells +72 μg/ml Nivolumab (all P <0.001), there was no significant difference in the killing activity between the 72 μg/ml and 36 μg/ml Nivolumab treated CD19-CAR-T cells on Pfeiffer cells ( P =0.281, 0.267, respectively), and they were all higher than those of 18 μg/ml Nivolumab treated CD19-CAR-T cells (all P <0.001). ③Different doses of PD-1 inhibitor Nivolumab combined with CD19-CAR-T cells does not affect the secretion of IFN-γ and IFN-α (all P >0.05). Conclusion: Combination of 36 μg/ml PD-1 inhibitor and CD19-CAR-T cells could reduce the drug toxicity and enhance the cytotoxicity.
- Published
- 2018
- Full Text
- View/download PDF
21. Reactive oxygen species mediated T lymphocyte abnormalities in an iron-overloaded mouse model and iron-overloaded patients with myelodysplastic syndromes.
- Author
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Chen J, Lu WY, Zhao MF, Cao XL, Jiang YY, Jin X, Xu P, Yuan TT, Zhang YC, Chai X, Meng JX, Li Q, Xiao X, Mu J, Li DG, and Qi AP
- Subjects
- Aged, Aged, 80 and over, Animals, CD3 Complex blood, CD4-CD8 Ratio, Disease Models, Animal, Female, Flow Cytometry, Humans, Iron Overload blood, Lymphocyte Count, Male, Mice, Inbred C57BL, Middle Aged, Myelodysplastic Syndromes blood, T-Lymphocytes metabolism, T-Lymphocytes, Regulatory metabolism, Th1 Cells metabolism, Th2 Cells metabolism, Iron Overload metabolism, Myelodysplastic Syndromes metabolism, Reactive Oxygen Species metabolism, T-Lymphocyte Subsets metabolism
- Abstract
The adverse effects of iron overload have raised more concerns as a growing number of studies reported its association with immune disorders. This study aimed to investigate alterations in the immune system by iron overload in patients with myelodysplastic syndrome (MDS) and an iron-overloaded mouse model. The peripheral blood from patients was harvested to test the effect of iron overload on the subsets of T lymphocytes, and the level of reactive oxygen species (ROS) was also evaluated. The data showed that iron-overloaded patients had a lower percentage of CD3
+ T cells and disrupted T cell subsets, concomitant with higher ROS level in lymphocytes. In order to explore the mechanism, male C57Bl/6 mice were intraperitoneally injected with iron dextran at a dose of 250 mg/kg every 3 days for 4 weeks to establish an iron-overloaded mouse model and the blood of each mouse was collected for the analysis of the T lymphocyte subsets and T cell apoptosis. The results showed that iron overload could reduce the percentage of CD3+ T cells and the ratio of Th1/Th2 and Tc1/Tc2 but increase the percentage of regulatory T (Treg) cells and the ratio of CD4/CD8. We also found that iron overload induced the apoptosis of T lymphocytes and increased its ROS level. Furthermore, these effects could be partially recovered after treating with antioxidant N-acetyl-L-cysteine (NAC) or iron chelator deferasirox (DFX). Taken together, these observations indicated that iron overload could selectively affect peripheral T lymphocytes and induce an impaired cellular immunity by increasing ROS level.- Published
- 2017
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- View/download PDF
22. Plasma miR-142 accounting for the missing heritability of CYP3A4/5 functionality is associated with pharmacokinetics of clopidogrel.
- Author
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Tang QJ, Lin HM, He GD, Liu JE, Wu H, Li XX, Zhong WP, Tang L, Meng JX, Zhang MZ, Li HP, Chen JY, Zhong SL, and Wang LY
- Subjects
- Adult, Aged, Aged, 80 and over, Clopidogrel, Coronary Disease drug therapy, Female, Humans, Liver enzymology, Male, Middle Aged, RNA, Messenger analysis, Ticlopidine pharmacokinetics, Cytochrome P-450 CYP3A genetics, MicroRNAs blood, Platelet Aggregation Inhibitors pharmacokinetics, Ticlopidine analogs & derivatives
- Abstract
Aim: To investigate whether plasma miRNAs targeting CYP3A4/5 have an impact on the variance of pharmacokinetics of clopidogrel., Materials & Methods: The contribution of 13 miRNAs to the CYP3A4/5 gene expression and activity was investigated in 55 liver tissues. The association between plasma miRNAs targeting CYP3A4/5 mRNA and clopidogrel pharmacokinetics was analyzed in 31 patients with coronary heart disease who received 300 mg loading dose of clopidogrel., Results: Among 13 miRNAs, miR-142 was accounting for 12.2% (p = 0.002) CYP3A4 mRNA variance and 9.4% (p = 0.005) CYP3A5 mRNA variance, respectively. Plasma miR-142 was negatively associated with H4 Cmax (r = -0.5269; p = 0.0040) and associated with H4 AUC0-4h (r = -0.4986; p = 0.0069) after 300 mg loading dose of clopidogrel in coronary heart disease patients., Conclusion: miR-142 could account for a part of missing heritability of CYP3A4/5 functionality related to clopidogrel activation.
- Published
- 2016
- Full Text
- View/download PDF
23. [Effects of iron overload on the peripheral blood T cells in mice].
- Author
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Chen J, Zhao MF, Cao XL, Meng JX, Xing Y, He XY, Jin X, Xu P, and Jiang YY
- Subjects
- Animals, Mice, Iron Overload immunology, T-Lymphocytes pathology
- Published
- 2016
- Full Text
- View/download PDF
24. The independent contribution of miRNAs to the missing heritability in CYP3A4/5 functionality and the metabolism of atorvastatin.
- Author
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Liu JE, Ren B, Tang L, Tang QJ, Liu XY, Li X, Bai X, Zhong WP, Meng JX, Lin HM, Wu H, Chen JY, and Zhong SL
- Subjects
- Adult, Aged, Gene Expression, Genetic Variation, Humans, Middle Aged, Young Adult, Atorvastatin metabolism, Cytochrome P-450 CYP3A genetics, MicroRNAs genetics, Microsomes, Liver metabolism
- Abstract
To evaluate the independent contribution of miRNAs to the missing heritability in CYP3A4/5 functionality and atorvastatin metabolism, the relationships among three levels of factors, namely (1) clinical characteristics, CYP3A4/5 genotypes, and miRNAs, (2) CYP3A4 and CYP3A5 mRNAs, and (3) CYP3A activity, as well as their individual impacts on atorvastatin metabolism, were assessed in 55 human liver tissues. MiR-27b, miR-206, and CYP3A4 mRNA respectively accounted for 20.0%, 5.8%, and 9.5% of the interindividual variations in CYP3A activity. MiR-142 was an independent contributor to the expressions of CYP3A4 mRNA (partial R(2) = 0.12, P = 0.002) and CYP3A5 mRNA (partial R(2) = 0.09, P = 0.005) but not CYP3A activity or atorvastatin metabolism. CYP3A activity was a unique independent predictor of variability of atorvastatin metabolism, explaining the majority of the variance in reduction of atorvastatin (60.0%) and formation of ortho-hydroxy atorvastatin (78.8%) and para-hydroxy atorvastatin (83.9%). MiR-27b and miR-206 were found to repress CYP3A4 gene expression and CYP3A activity by directly binding to CYP3A4 3'-UTR, while miR-142 was found to indirectly repress CYP3A activity. Our study indicates that miRNAs play significant roles in bridging the gap between epigenetic effects and missing heritability in CYP3A functionality.
- Published
- 2016
- Full Text
- View/download PDF
25. [Establishment of macrophage model of iron overload in vitro and the injury induced by oxidative stress on macrophage with iron overload].
- Author
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Cao XL, Zhao MF, Li DG, Xing Y, Zhang YC, Chen J, He XY, Cui R, Meng JX, Xiao X, Mu J, Jiang YY, and Wu RM
- Subjects
- Acetylcysteine, Antioxidants, Down-Regulation, Ferric Compounds, Humans, Iron, Phosphatidylinositol 3-Kinases, Quaternary Ammonium Compounds, Reactive Oxygen Species, Signal Transduction, Iron Overload, Macrophages, Oxidative Stress
- Abstract
Objective: To establish macrophage iron overload model in vitro by co-culture macrophages with iron, and to explore the effect of iron overload on cell reactive oxygen species (ROS) and the impact of ROS on macrophages., Method: Iron overload group were treated with different concentrations (0, 5, 10, 20, 40, 80 μmol/L respectively) of ferric ammonium citrate (FAC). The control group was the group of macrophages without FAC treatment. We detected the number and state of cells, metabolic activity, the change of phagocytosis, the levels of ROS and reactive nitrogen, and changes of related oxidative stress signaling pathways in different groups. Changes in the above indexes were detected after application of deferasirox (DFX) to remove iron and the antioxidant N -acetylcysteine (NAC) to clear excess oxidative stress., Results: (1)The levels of labile iron pool (LIP) in macrophages co-cultivated with iron was increased with the increase of iron concentration in a dose-dependent manner. The LIP levels was the highest in the macrophages treated with 80 μmol/L. (2)The increase of FAC concentration, the metabolic activity of macrophages in the 5 FAC-treated groups decreased to 51.58%, 40.98%, 16.23%, 3.46%, and 0.05% of the activity level of the control group (all P< 0.05). The group with the metabolic activity decreased to 16.23% (20 μmol/L) was selected as the iron overload group for the following experiments. (3)Compared with the control group, the number of macrophages in the iron overload group reduced to 32.80% (P<0.05), and the state of cells changed from adherence to partial suspension. The phagocytosis of macrophages in the iron overload group reduced to 20.40% of the control group (P<0.05). (4)Our further experiment showed that the levels of ROS and the activity nitrogen in the iron overload group increased by 7.71-and 1.45-fold compared with the control group (both P<0.05). The RT-PCR showed up-regulated mRNA expression of genes related with ROS production, i. e. nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX 4) gene related with ROS production and inducible nitric oxide synthase (iNOS) gene related with reactive nitrogen production, down-regulated mRNA expression of glutathione peroxidase 1 (GPX1) gene which participated in ROS clearance. Moreover, mRNA expression of phosphatidylinositol-3-kinase (PI3K) gene involved in oxidative stress signaling pathway in the iron overload group was up-regulated, while fork head protein O3 (FOXO3) which regulated oxidative stress through negative feedback showed a down-regulation level of mRNA expression compared with the control group. (5)After iron chelation and antioxidant treatment, the above-mentioned damage in the iron overload group were partially reversed., Conclusions: The damages of iron overload on macrophages may be mediated by inducing oxidative stress and activating oxidative stress signaling pathways. Our established model provides a method to explore the mechanism of iron overload on macrophage, and may shed some new light on possible therapeutic target in treating iron overload patients.
- Published
- 2016
- Full Text
- View/download PDF
26. [Reactive oxygen species mediate the injury and deficient hematopoietic supportive capacity of umbilical cord derived mesenchymal stem cells induced by iron overload].
- Author
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Lu WY, Zhao MF, Chai X, Meng JX, Zhao N, Rajbhandary S, Xu XN, Ma L, and Li YM
- Subjects
- Cell Proliferation, Cells, Cultured, Culture Media, Humans, Signal Transduction, Umbilical Cord cytology, Hematopoietic System, Iron Overload, Mesenchymal Stem Cells cytology, Reactive Oxygen Species metabolism
- Abstract
Objective: To explore the effects of iron overload on umbilical cord derived mesenchymal stem cells (UC-MSC) and elucidate the involvement of reactive oxygen species (ROS) in this process., Methods: The iron overload model of MSC was established by in vitro addition of ferric ammonium citrate (FAC) into culture medium. Cell proliferation and apoptosis were determined by Annexin V/PI double staining and population doubling time (DT) respectively. Co-culture system was used to assess the hematopoietic support capacity of UC-MSC in different groups. Thereafter the ROS level was detected with fluorescent probe 2', 7'-dichlorofluorescin diacetate (DCFH-DA). And the ROS related signaling factors of p-p38MAPK, p38 MAPK, P53 were measured by Western blot., Results: (1) The DT of UC-MSC in iron overload group was significantly longer than that of control ((24.43 ± 2.72) h vs (16.03 ± 2.31) h, P < 0.05). But the difference was insignificant after two passages (P > 0.05). (2) Apoptosis in iron overload group was higher than that of control (12.75% ± 0.32% vs 3.63% ± 0.80%, P < 0.05). (3) The colony forming capacity of mononuclear cell (MNC) co-cultured with UC-MSC of iron overload group for 1/2 weeks significantly decreased. (4) The ROS level of UC-MSC with iron overload was higher than that of control in time and concentration-dependent fashions and it peaked at 400 µmol/L of FAC for 12 h (1499 ± 86 vs 548 ± 97, P < 0.05). (5) The expressions of p-p38MAPK and P53 increased in response to FAC compared with control. But such an effect was partially inhibited after the use of antioxidants., Conclusions: Iron overload may impair the proliferation, survival and hematopoiesis supportive function of UC-MSC by enhancing the generation of ROS. And ROS stimulates the signaling pathways of p-p38MAPK and P53.
- Published
- 2013
27. Association of β-adrenergic receptor genes polymorphisms with incidence of subsequent cardiovascular events in Han Chinese patients with coronary artery disease.
- Author
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Li ZG, Wu H, Zhou YL, Chen ZJ, Meng JX, Yang JQ, Chen JY, and Zhong SL
- Subjects
- Adult, Aged, Aged, 80 and over, Asian People genetics, Female, Genotype, Humans, Incidence, Male, Middle Aged, Polymorphism, Single Nucleotide genetics, Receptors, Adrenergic, beta-1 genetics, Receptors, Adrenergic, beta-2 genetics, Coronary Artery Disease genetics, Polymorphism, Genetic genetics, Receptors, Adrenergic, beta genetics
- Abstract
Background: Sequence variants in the β-adrenergic receptor (ADRB) genes have a close relationship with the development of coronary artery disease (CAD) and the patient's prognosis. However, there is a lack of data on the role of the variants in ADRBs genes in Han Chinese patients with CAD. We aimed to investigate the association of genetic variants in the ADRB1 and ADRB2 genes with the incidence of major adverse cardiac event (MACE) in Han Chinese patients with CAD., Methods: A total of 545 Han Chinese patients with CAD undergoing percutaneous coronary intervention (PCI) were recruited to the study and followed for one year. Three variant sites in ADRB1 (rs1801253) and ADRB2 (rs1042713 and rs1042714) were genotyped. The effect of the ADRB1 and ADRB2 genotypes on MACE within one year was assessed., Results: There were 47 cases of MACE during follow-up. There was no significant difference in the incidence of MACE among patients carrying different genotypes of the three variants in ADRB1 and ADRB2 (Log-rank, all P > 0.05). Cox regression analysis showed no association between three variants in ADRB1 and ADRB2 genes and the incidence of MACE during one-year follow-up, the adjusted hazard ratios (95% confidence interval) for rs1801253, rs1042713 and rs1042714 were 1.05 (0.54-2.02), 1.24 (0.58-2.64) and 1.66 (0.81-3.42), respectively., Conclusion: Our data did not support a relationship between the three polymorphisms of ADRB1 (rs1801253) and ADRB2 (rs1042713 and rs1042714) genes and risk of subsequent cardiovascular events after PCI in Han Chinese patients with CAD.
- Published
- 2013
28. [Screening and identification of auto-antigen RHDAG1 of rheumatic heart disease].
- Author
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Meng JX, Li YX, Zhu P, Li L, Lu C, Zheng SY, Li GH, and Yu XY
- Subjects
- Autoantibodies immunology, Autoantigens isolation & purification, Autoimmune Diseases blood, Humans, Peptide Library, Autoantibodies blood, Autoantigens immunology, Autoimmune Diseases immunology, Rheumatic Heart Disease immunology
- Abstract
Objective: To identify the candidate auto-antigen of rheumatic heart disease as a molecular marker for this disease., Methods: The total RNA of the heart tissue of patients with rheumatic heart disease was extracted and reverse-transcribed into long cDNA to construct the phage expression library. The library was screened using the serum from patients with active rheumatic fever, and the positive clone was identified and analyzed by bioinformatics and expressed in vitro. The expressed products were evaluated with Western blotting and its cross-reactivity was assessed., Results: The phage expression library of the heart tissue of patients with rheumatic heart disease was constructed, with the titer of the primary library of 3.3×10(6) pfu/ml, recombinant rate of 99%, and 81% of the inserted segments were larger than 1 kb. An auto-antigen RHDAG1 was identified by screening, which was homologous to keratin 18. RHDAG1 was detected in the serum of patients with active rheumatic fever and of those with rheumatic heart disease, but not in the serum of healthy subjects., Conclusion: Phage display library can be an effective strategy to screen the auto-antigens of rheumatic heart disease. The auto-antigen RHDAG1 can be a candidate molecular biomarker of rheumatic heart disease and/or rheumatic fever.
- Published
- 2011
29. Synthesis of Y 2 O 2 S:Eu 3+ , Mg 2+ , Ti 4+ hollow microspheres via homogeneous precipitation route.
- Author
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Ai PF, Liu YL, Xiao LY, Wang HJ, and Meng JX
- Abstract
A phosphorescent material in the form of Y
2 O2 S:Eu3+ , Mg2+ , Ti4+ hollow microspheres was prepared by homogeneous precipitation using monodispersed carbon spheres as hard templates. Y2 O3 :Eu3+ hollow microspheres were first synthesized to serve as the precursor. Y2 O2 S:Eu3+ , Mg2+ , Ti4+ powders were obtained by calcinating the precursor in a CS2 atmosphere. The crystal structure, morphology and optical properties of the composites were characterized. X-ray diffraction measurements confirmed the purity of the Y2 O2 S phase. Electron microscopy observations revealed that the Y2 O2 S:Eu3+ , Mg2+ , Ti4+ particles inherited the hollow spherical shape from the precursor after being calcined in a CS2 atmosphere and that they had a diameter of 350-450 nm and a wall thickness of about 50-80 nm. After ultraviolet radiation at 265 or 325 nm for 5 min, the particles emitted strong red long-lifetime phosphorescence originating from Eu3+ ions. This phosphorescence is associated with the trapping of charge carriers by Ti4+ and Mg2+ ions.- Published
- 2010
- Full Text
- View/download PDF
30. [siRNAs targetting sphingomyelin phosphodiesterase 1 protect mouse oocytes from apoptosis].
- Author
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Zhang RL, Meng JX, Wen AM, Huang YS, Zhou CQ, Wang K, Jia L, Liu CX, Deng XY, and Chen XG
- Subjects
- Animals, Apoptosis drug effects, Comet Assay, Female, Mice, RNA Interference, Sphingomyelin Phosphodiesterase physiology, Transfection, Apoptosis genetics, Oocytes cytology, RNA, Small Interfering genetics, Sphingomyelin Phosphodiesterase genetics
- Abstract
Objective: To investigate the potential of siRNAs targeting sphingomyelin phosphodiesterase 1 (SMPD1) in protecting the oocytes from apoptosis, and explore new approaches to female fertility preservation., Methods: Chemically synthesized siRNA targeting SMPD1 were introduced into mouse oocytes retrieved by hyperstimulation, and the cell apoptosis was analyzed by comic assay 48 and 72 h later., Results: In the oocytes without any siRNA injection, oocyte DNA damage occurred after 24 h, and large amount of DNA fragments migrated from the cells 48 h later. In oocytes injected with siRNA003, DNA migration decreased significantly as compared with the control and the other two groups injected with siRNA001 and siRNA002 (P<0.01)., Conclusion: siRNA targeting SMPD1 may protect the oocytes from apoptosis, and has the potential for use in future female fertility preservation.
- Published
- 2009
31. [Identification and tissue localization of intermediate filament protein in Angiostrongylus cantonensis].
- Author
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Meng JX, He A, Cheng M, Xu GF, Li ZY, Yu XY, Jiang WL, Li YX, and Zhan XM
- Subjects
- Angiostrongylus cantonensis metabolism, Animals, Cell Nucleus metabolism, Electrophoresis, Polyacrylamide Gel, Intermediate Filament Proteins genetics, Intermediate Filament Proteins isolation & purification, Protein Transport, Angiostrongylus cantonensis cytology, Intermediate Filament Proteins classification, Intermediate Filament Proteins metabolism
- Abstract
Objective: To identify the type of the intermediate filament (IF) protein of Angiostrongylus cantonensis and analyze its tissue localization., Methods: Recombinant pET-IF of antigen IF was expressed in E.coli with IPTG induction, and the expression products were purified by His.Bind column and identified for determining the type of the IF protein by Western blotting. Anti-IF antibody was prepared by multi-spot subcutaneous injection into mouse and used to detect the tissue slices of A. cantonensis by immunohistochemical analysis., Results: The antigen IF were correctly expressed and purified, and identified as a keratin located in the intestine wall and cytoplusma., Conclusion: The antigen IF is distributed in the intestine wall of A. cantonensis.
- Published
- 2007
32. [Induced differentiation and signaling factor PTEN expression of 3T3-L1 adipocytes].
- Author
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Li YX, Meng JX, Cai XZ, Li DF, Rong KB, Jiang WL, Zhang RL, and Yu XY
- Subjects
- 3T3-L1 Cells, Adipocytes cytology, Adipocytes drug effects, Animals, Blotting, Western, Cell Differentiation genetics, Cell Differentiation physiology, Glucose pharmacology, Humans, Mice, PTEN Phosphohydrolase genetics, RNA, Messenger biosynthesis, RNA, Messenger genetics, Adipocytes metabolism, Cell Differentiation drug effects, PTEN Phosphohydrolase metabolism
- Abstract
Objective: To optimize the condition for inducing the differentiation of 3T3-L1 preadipocytes into adipocytes and study the expression of PTEN tumor suppression gene in this process, aiming to understand the regulatory role of PTEN in normal adipocyte differentiation and collect laboratory evidence for developing drugs targeting PTEN., Methods: The differentiation of 3T3-L1 preadipocytes cultured in high-glucose DMEM were induced according to 2 protocols with different combinations of dexamethasone, isobutylmethylxanthine (IBMX) and insulin, and the resultant adipocytes were identified by oil red O staining. The total proteins of 3T3-L1 were extracted and analyzed by Western blotting, and PTEN homology between mice and human was analyzed by bioinformatic method., Results: For optimized 3T3-L1 differentiation, 3T3-L1 cells were initially induced with the combination of 1 micromol/L dexamethasone, 0.5 mmol/L IBMX and 5 microg/ml insulin for 48 h, followed by treatment with 5 microg/ml insulin in 4.5 g/L glucose DMEM for 48 h, which resulted in high differentiation rate of 3T3-L1 cells (up to 90% on the 10th day) with unified morphology and size. PTEN expression varied quantitatively in the process of differentiation, especially low on the 12th day as compared with those measured on days 4, 6 and 9. The mice PTEN mRNA shared 96% homology and PTEN amino acid 100% homology with their human counterparts., Conclusion: Endogenous PTEN expression is down-regulated during 3T3-L1 differentiation, suggesting that PTEN may enhance insulin sensitivity and promote adipogenesis under physiological conditions.
- Published
- 2007
33. Schistosoma japonicum: construction of phage display antibody library and its application in the immunodiagnosis of infection.
- Author
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Chen DX, He A, Zhan XM, Yu MH, Lei ZG, Meng JX, Li ZY, Liang Y, and Zhang RL
- Subjects
- Animals, Base Sequence, Immunoglobulin Fragments immunology, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Rabbits, Sensitivity and Specificity, Serologic Tests, Antibodies, Helminth immunology, Antibodies, Monoclonal immunology, Antigens, Helminth blood, Peptide Library, Schistosomiasis japonica diagnosis
- Abstract
Background: A monoclonal antibody would be an effective tool for the detection of circulating antigens in the serum of patients with schistosomiasis, but the traditional way of producing monoclonal antibodies is not cost-effective. The objective of this study was to find a new method for the large-scale production of monoclonal antibodies against Schistosoma japonicum (Sj)., Methods: A phage display antibody library for Sj was constructed. To obtain a single-chain variable fragment antibody (scFv) against Sj, the library was screened with metabolic antigens from adult Sj worms (Sj-MAg) using enzyme-linked immunosorbent assay. The soluble scFvs selected were used to detect Sj antigens in the serum of acute and chronic schistosomiasis patients., Results: Six positive clones with good reactivity to Sj-MAg were obtained from the phage display antibody library of about 1.07 x 10(6) individual clones. Only two of these six clones bound specifically to Sj-MAg and were chosen for further analysis. Specific soluble anti-Sj-MAg scFvs were produced by inducing the 2 clones with isopropyl-D-thiogalactopyranoside. The characteristics of the scFvs were then determined. The results of Western blot showed that these scFvs could bind to Sj-MAg specifically and had a molecular weight of about 31 kD. When testing serum from schistosomiasis patients with one of the two specific scFvs, its sensitivity was found to be 60% and 37% in acute and chronic patients, respectively, with a specificity of 90%. When the two specific scFvs were combined, their sensitivity was found to be 75% and 57% in acute and chronic patients, respectively, with a specificity of 85%., Conclusions: The results indicate that the scFvs are potentially useful for the diagnosis of schistosomiasis. The library construction also provides a useful tool for the further screening of other antibodies for both diagnostic and immunotherapeutic applications and for epitope analysis and vaccine design.
- Published
- 2004
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