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Akinci A, Kara A, Özgür A, Turkkahraman D, Aksu S. Genomic analysis to screen potential genes and mutations in children with non-syndromic early onset severe obesity: a multicentre study in Turkey. Mol Biol Rep 2021; 49:1883-1893. [PMID: 34850337 DOI: 10.1007/s11033-021-06999-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 11/19/2021] [Indexed: 01/06/2023]
Abstract
BACKGROUND Obesity is a complex genetic-based pediatric disorder which triggers life-threatening conditions. Therefore, the understanding the molecular mechanisms of obesity has been a significant approach in medicine. Computational methods allow rapid and comprehensive pathway analysis, which is important for generation of diagnosis and treatment of obesity. METHODS AND RESULTS Aims of our study are to comprehensively investigate genetic characteristics of obesity in children with non-syndromic, early-onset (< 7 years), and severe obesity (BMI-SDS > 3) through computational approaches. First, the mutational analyses of 41 of obesity-related genes in 126 children with non-syndromic early-onset severe obesity and 76 healthy non-obese controls were performed using the next generation sequencing (NGS) technique, and the NGS data analyzed by using bioinformatics methods. Then, the relationship between pathogenic variants and anthropometric/biochemical parameters was further evaluated. Obtained results demonstrated that the 15 genes (ADIPOQ, ADRB2, ADRB3, IRS1, LEPR, NPY, POMC, PPARG, PPARGC1A, PPARGC1B, PTPN1, SLC22A1, SLC2A4, SREBF1 and UCP1) which directly related to obesity found linked together via biological pathways and/or functions. Among these genes, IRS1, PPARGC1A, and SLC2A4 stand out as the most central ones. Furthermore, 12 of non-synonymous pathogenic variants, including six novels, were detected on ADIPOQ (G90S and D242G), ADRB2 (V87M), PPARGC1A (E680G, A477T, and R656H), UCP1 (Q44R), and IRS1 (R302Q, R301H, R301C, H250P, and H250N) genes. CONCLUSION We propose that 12 of non-synonymous pathogenic variations detected on ADIPOQ, ADRB2, PPARGC1A, UCP1, and IRS1 genes might have a cumulative effect on the development and progression of obesity.
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Affiliation(s)
- Aysehan Akinci
- Pediatric Endocrinology and Diabetes Department, Medical Faculty, Inonu University, Malatya, Turkey.
| | - Altan Kara
- Genetic Engineering and Bioinformatic Department, TUBITAK Marmara Research Center, Gebze, Turkey.
| | - Aykut Özgür
- Laboratory and Veterinary Health Program, Department of Veterinary Medicine, Artova Vocational School, Tokat Gaziosmanpaşa University, Tokat, Turkey
| | - Doga Turkkahraman
- Pediatric Endocrinology Department, Antalya Training and Research Hospital, University of Health Sciences, Antalya, Turkey
| | - Soner Aksu
- Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Istanbul Health and Technology University, İstanbul, Turkey
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2
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Gao ZY, Su LC, Wu QC, Sheng JE, Wang YL, Dai YF, Chen AP, He SS, Huang X, Yan GQ. Bioinformatics analyses of gene expression profile identify key genes and functional pathways involved in cutaneous lupus erythematosus. Clin Rheumatol 2021; 41:437-452. [PMID: 34553293 DOI: 10.1007/s10067-021-05913-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/05/2021] [Accepted: 09/05/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Lupus erythematosus is an autoimmune disease that causes damage to multiple organs ranging from skin lesions to systemic manifestations. Cutaneous lupus erythematosus (CLE) is a common type of lupus erythematosus (LE), but its molecular mechanisms are currently unknown. The study aimed to explore changes in the gene expression profiles and identify key genes involved in CLE, hoping to uncover its molecular mechanism and identify new targets for CLE. METHOD We analyzed the microarray dataset (GSE109248) derived from the Gene Expression Omnibus (GEO) database, which was a transcriptome profiling of CLE cutaneous lesions. The differentially expressed genes (DEGs) were identified, and the functional annotation of DEGs was performed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Protein-protein interaction (PPI) network was also constructed to identify hub genes involved in CLE. RESULT A total of 755 up-regulated DEGs and 405 down-regulated DEGs were identified. GO enrichment analysis showed that defense response to virus, immune response, and type I interferon signaling pathway were the most significant enrichment items in DEGs. The KEGG pathway analysis identified 51 significant enrichment pathways, which mainly included systemic lupus erythematosus, osteoclast differentiation, cytokine-cytokine receptor interaction, and primary immunodeficiency. Based on the PPI network, the study identified the top 10 hub genes involved in CLE, which were CXCL10, CCR7, FPR3, PPARGC1A, MMP9, IRF7, IL2RG, SOCS1, ISG15, and GSTM3. By comparison between subtypes, the results showed that ACLE had the least DEGs, while CCLE showed the most gene and functional changes. CONCLUSION The identified hub genes and functional pathways found in this study may expand our understanding on the underlying pathogenesis of CLE and provide new insights into potential biomarkers or targets for the diagnosis and treatment of CLE. Key Points • The bioinformatics analysis based on CLE patients and healthy controls was performed and 1160 DEGs were identified • The 1160 DEGs were mainly enriched in biological processes related to immune responses, including innate immune response, type I interferon signaling pathway, interferon-γ-mediated signaling pathway, positive regulation of T cell proliferation, regulation of immune response, antigen processing, and presentation via MHC class Ib and so on • KEGG pathway enrichment analysis indicated that DEGs were mainly enriched in several immune-related diseases and virus infection, including systemic lupus erythematosus, primary immunodeficiency, herpes simplex infection, measles, influenza A, and so on • The hub genes such as CXCL10, IRF7, MMP9, CCR7, and SOCS1 may become new markers or targets for the diagnosis and treatment of CLE.
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Affiliation(s)
- Zhen-Yu Gao
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China. .,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.
| | - Lin-Chong Su
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Qing-Chao Wu
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Jiao-E Sheng
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Yun-Long Wang
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Yu-Fang Dai
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - An-Ping Chen
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - San-Shan He
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Xia Huang
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
| | - Guo-Qing Yan
- Department of Rheumatology and Immunology, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China.,Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic Disease, The Affiliated Hospital of Hubei Minzu University, Enshi, Hubei Province, China
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3
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Abdrabou W, Dieng MM, Diawara A, Sermé SS, Almojil D, Sombié S, Henry NB, Kargougou D, Manikandan V, Soulama I, Idaghdour Y. Metabolome modulation of the host adaptive immunity in human malaria. Nat Metab 2021; 3:1001-1016. [PMID: 34113019 DOI: 10.1038/s42255-021-00404-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 05/07/2021] [Indexed: 02/06/2023]
Abstract
Host responses to infection with the malaria parasite Plasmodium falciparum vary among individuals for reasons that are poorly understood. Here we reveal metabolic perturbations as a consequence of malaria infection in children and identify an immunosuppressive role of endogenous steroid production in the context of P. falciparum infection. We perform metabolomics on matched samples from children from two ethnic groups in West Africa, before and after infection with seasonal malaria. Analysing 306 global metabolomes, we identify 92 parasitaemia-associated metabolites with impact on the host adaptive immune response. Integrative metabolomic and transcriptomic analyses, and causal mediation and moderation analyses, reveal an infection-driven immunosuppressive role of parasitaemia-associated pregnenolone steroids on lymphocyte function and the expression of key immunoregulatory lymphocyte genes in the Gouin ethnic group. In children from the less malaria-susceptible Fulani ethnic group, we observe opposing responses following infection, consistent with the immunosuppressive role of endogenous steroids in malaria. These findings advance our understanding of P. falciparum pathogenesis in humans and identify potential new targets for antimalarial therapeutic interventions.
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Affiliation(s)
- Wael Abdrabou
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
- Department of Biology, New York University, New York, NY, USA
| | - Mame Massar Dieng
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Aïssatou Diawara
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Samuel Sindié Sermé
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Dareen Almojil
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Salif Sombié
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Noelie Bere Henry
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Désiré Kargougou
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Vinu Manikandan
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Issiaka Soulama
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Youssef Idaghdour
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.
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4
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Machado FC, Bittar C, Rahal P, Calmon MF. Identification of differentially expressed miRNAs in human cells infected with different Zika virus strains. Arch Virol 2021; 166:1681-1689. [PMID: 33847814 DOI: 10.1007/s00705-021-05051-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 02/08/2021] [Indexed: 12/12/2022]
Abstract
Infection with distinct Zika virus (ZIKV) strains in in vitro and in vivo models has demonstrated that the host's response to infection is strain-dependent. There has been no analysis of the impact of infection with different ZIKV strains on miRNA expression in human cells. We investigated miRNA expression in PNT1A cells upon infection with an African ZIKV strain (MR766) and a Brazilian ZIKV strain (ZIKVBR) using PCR array. Sixteen miRNAs were modulated in PNT1A cells: six miRNAs were modulated by both strains, while a set of ten miRNAs were modulated exclusively by ZIKVBR infection. In silico analysis showed that nine significant KEGG pathways and eight significant GO terms were predicted to be enriched upon ZIKVBR infection, and these pathways were related to cancer, environmental information processing, metabolism, and extracellular matrix. Differential modulation of miRNA expression suggests that distinct strains of ZIKV can differentially modulate the host response through the action of miRNAs.
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Affiliation(s)
- Francielly Cristina Machado
- Department of Biology, IBILCE, Institute of Biosciences, Humanities and Exact Sciences, UNESP, São Paulo State University, Rua Cristóvão Colombo, 2265, Bairro Jardim Nazareth, São José do Rio Preto, SP, 15054-010, Brazil
| | - Cíntia Bittar
- Department of Biology, IBILCE, Institute of Biosciences, Humanities and Exact Sciences, UNESP, São Paulo State University, Rua Cristóvão Colombo, 2265, Bairro Jardim Nazareth, São José do Rio Preto, SP, 15054-010, Brazil
| | - Paula Rahal
- Department of Biology, IBILCE, Institute of Biosciences, Humanities and Exact Sciences, UNESP, São Paulo State University, Rua Cristóvão Colombo, 2265, Bairro Jardim Nazareth, São José do Rio Preto, SP, 15054-010, Brazil
| | - Marilia Freitas Calmon
- Department of Biology, IBILCE, Institute of Biosciences, Humanities and Exact Sciences, UNESP, São Paulo State University, Rua Cristóvão Colombo, 2265, Bairro Jardim Nazareth, São José do Rio Preto, SP, 15054-010, Brazil.
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5
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Ozawa T, Kaneko S, Szulzewsky F, Qiao Z, Takadera M, Narita Y, Kondo T, Holland EC, Hamamoto R, Ichimura K. C11orf95-RELA fusion drives aberrant gene expression through the unique epigenetic regulation for ependymoma formation. Acta Neuropathol Commun 2021; 9:36. [PMID: 33685520 PMCID: PMC7941712 DOI: 10.1186/s40478-021-01135-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 02/21/2021] [Indexed: 12/13/2022] Open
Abstract
Recurrent C11orf95-RELA fusions (RELAFUS) are the hallmark of supratentorial ependymomas. The presence of RELA as the fusion partner indicates a close association of aberrant NF-κB activity with tumorigenesis. However, the oncogenic role of the C11orf95 has not been determined. Here, we performed ChIP-seq analyses to explore genomic regions bound by RELAFUS and H3K27ac proteins in human 293T and mouse ependymoma cells. We then utilized published RNA-Seq data from human and mouse RELAFUS tumors and identified target genes that were directly regulated by RELAFUS in these tumors. Subsequent transcription factor motif analyses of RELAFUS target genes detected a unique GC-rich motif recognized by the C11orf95 moiety, that is present in approximately half of RELAFUS target genes. Luciferase assays confirmed that a promoter carrying this motif is sufficient to drive RELAFUS-dependent gene expression. Further, the RELAFUS target genes were found to be overlapped with Rela target genes primarily via non-canonical NF-κB binding sites. Using a series of truncation and substitution mutants of RELAFUS, we also show that the activation domain in the RELAFUS moiety is necessary for the regulation of gene expression of these RELAFUS target genes. Lastly, we performed an anti-cancer drug screening with mouse ependymoma cells and identified potential anti-ependymoma drugs that are related to the oncogenic mechanism of RELAFUS. These findings suggested that RELAFUS might induce ependymoma formation through oncogenic pathways orchestrated by both C11orf95 and RELA target genes. Thus, our study unveils a complex gene function of RELAFUS as an oncogenic transcription factor in RELAFUS positive ependymomas.
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6
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Briuglia S, Calabrò M, Capra AP, Briguori S, La Rosa MA, Crisafulli C. Molecular Pathways within Autism Spectrum Disorder Endophenotypes. J Mol Neurosci 2021; 71:1357-1367. [PMID: 33492615 DOI: 10.1007/s12031-020-01782-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/16/2020] [Indexed: 12/19/2022]
Abstract
Autism spectrum disorder (ASD) is a condition that includes a number of neurodevelopmental mental disorders. Recent genetic/genomic investigations have reported an increased prevalence of copy number variations (CNVs) in individuals with autism. Despite the extensive evidence of a genetic component, the genes involved are not known and the background is heterogeneous among subjects. As such, it is highly likely that multiple events (molecular cascades) are implicated in the development of autism. The aim of this work was to shed some light on the biological background behind this condition. We hypothesized that the heterogeneous alterations found within different individuals may converge into one or more specific biological functions (pathways) linked to the heterogeneous phenotypes commonly observed in subjects with ASD. We analyzed a sample of 107 individuals for CNV alterations and checked the genes located within the altered loci (1366). Then, we characterized the subjects for distinct phenotypes. After creating subsamples based on symptoms, the CNVs related to each specific symptom were used to create distinct networks associated with each phenotype (18 in total in the sample under analysis). These networks were independently clustered and enriched to identify potential common pathways involved in autism and variably combined with the clinical phenotype. The first 10 pathways of the analysis are discussed.
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Affiliation(s)
- Silvana Briuglia
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy
| | - Marco Calabrò
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy
| | - Anna Paola Capra
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy
| | - Sara Briguori
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy
| | - Maria Angela La Rosa
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy
| | - Concetta Crisafulli
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Torre Biologica Via C. Valeria-Gazzi, Messina, 98125, Italy.
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7
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Disruption of NEUROD2 causes a neurodevelopmental syndrome with autistic features via cell-autonomous defects in forebrain glutamatergic neurons. Mol Psychiatry 2021; 26:6125-6148. [PMID: 34188164 PMCID: PMC8760061 DOI: 10.1038/s41380-021-01179-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 05/17/2021] [Accepted: 05/26/2021] [Indexed: 02/06/2023]
Abstract
While the transcription factor NEUROD2 has recently been associated with epilepsy, its precise role during nervous system development remains unclear. Using a multi-scale approach, we set out to understand how Neurod2 deletion affects the development of the cerebral cortex in mice. In Neurod2 KO embryos, cortical projection neurons over-migrated, thereby altering the final size and position of layers. In juvenile and adults, spine density and turnover were dysregulated in apical but not basal compartments in layer 5 neurons. Patch-clamp recordings in layer 5 neurons of juvenile mice revealed increased intrinsic excitability. Bulk RNA sequencing showed dysregulated expression of many genes associated with neuronal excitability and synaptic function, whose human orthologs were strongly associated with autism spectrum disorders (ASD). At the behavior level, Neurod2 KO mice displayed social interaction deficits, stereotypies, hyperactivity, and occasionally spontaneous seizures. Mice heterozygous for Neurod2 had similar defects, indicating that Neurod2 is haploinsufficient. Finally, specific deletion of Neurod2 in forebrain excitatory neurons recapitulated cellular and behavioral phenotypes found in constitutive KO mice, revealing the region-specific contribution of dysfunctional Neurod2 in symptoms. Informed by these neurobehavioral features in mouse mutants, we identified eleven patients from eight families with a neurodevelopmental disorder including intellectual disability and ASD associated with NEUROD2 pathogenic mutations. Our findings demonstrate crucial roles for Neurod2 in neocortical development, whose alterations can cause neurodevelopmental disorders including intellectual disability and ASD.
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8
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Durbin HJ, Lu D, Yampara-Iquise H, Miller SP, Decker JE. Development of a genetic evaluation for hair shedding in American Angus cattle to improve thermotolerance. Genet Sel Evol 2020; 52:63. [PMID: 33087048 PMCID: PMC7579828 DOI: 10.1186/s12711-020-00584-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 10/09/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Heat stress and fescue toxicosis caused by ingesting tall fescue infected with the endophytic fungus Epichloë coenophiala represent two of the most prevalent stressors to beef cattle in the United States and cost the beef industry millions of dollars each year. The rate at which a beef cow sheds her winter coat early in the summer is an indicator of adaptation to heat and an economically relevant trait in temperate or subtropical parts of the world. Furthermore, research suggests that early-summer hair shedding may reflect tolerance to fescue toxicosis, since vasoconstriction induced by fescue toxicosis limits the ability of an animal to shed its winter coat. Both heat stress and fescue toxicosis reduce profitability partly via indirect maternal effects on calf weaning weight. Here, we developed parameters for routine genetic evaluation of hair shedding score in American Angus cattle, and identified genomic loci associated with variation in hair shedding score via genome-wide association analysis (GWAA). RESULTS Hair shedding score was moderately heritable (h2 = 0.34 to 0.40), with different repeatability estimates between cattle grazing versus not grazing endophyte-infected tall fescue. Our results suggest modestly negative genetic and phenotypic correlations between a dam's hair shedding score (lower score is earlier shedding) and the weaning weight of her calf, which is one metric of performance. Together, these results indicate that economic gains can be made by using hair shedding score breeding values to select for heat-tolerant cattle. GWAA identified 176 variants significant at FDR < 0.05. Functional enrichment analyses using genes that were located within 50 kb of these variants identified pathways involved in keratin formation, prolactin signalling, host-virus interaction, and other biological processes. CONCLUSIONS This work contributes to a continuing trend in the development of genetic evaluations for environmental adaptation. Our results will aid beef cattle producers in selecting more sustainable and climate-adapted cattle, as well as enable the development of similar routine genetic evaluations in other breeds.
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Affiliation(s)
| | - Duc Lu
- Angus Genetics Inc., St. Joseph, MO 64506 USA
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9
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Vijaya Kumar S, Abraham PE, Hurst GB, Chourey K, Bible AN, Hettich RL, Doktycz MJ, Morrell-Falvey JL. A carotenoid-deficient mutant of the plant-associated microbe Pantoea sp. YR343 displays an altered membrane proteome. Sci Rep 2020; 10:14985. [PMID: 32917935 PMCID: PMC7486946 DOI: 10.1038/s41598-020-71672-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 08/05/2020] [Indexed: 01/08/2023] Open
Abstract
Membrane organization plays an important role in signaling, transport, and defense. In eukaryotes, the stability, organization, and function of membrane proteins are influenced by certain lipids and sterols, such as cholesterol. Bacteria lack cholesterol, but carotenoids and hopanoids are predicted to play a similar role in modulating membrane properties. We have previously shown that the loss of carotenoids in the plant-associated bacteria Pantoea sp. YR343 results in changes to membrane biophysical properties and leads to physiological changes, including increased sensitivity to reactive oxygen species, reduced indole-3-acetic acid secretion, reduced biofilm and pellicle formation, and reduced plant colonization. Here, using whole cell and membrane proteomics, we show that the deletion of carotenoid production in Pantoea sp. YR343 results in altered membrane protein distribution and abundance. Moreover, we observe significant differences in the protein composition of detergent-resistant membrane fractions from wildtype and mutant cells, consistent with the prediction that carotenoids play a role in organizing membrane microdomains. These data provide new insights into the function of carotenoids in bacterial membrane organization and identify cellular functions that are affected by the loss of carotenoids.
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Affiliation(s)
- Sushmitha Vijaya Kumar
- UT-ORNL Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA
| | - Paul E Abraham
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Gregory B Hurst
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Karuna Chourey
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Amber N Bible
- UT-ORNL Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA
| | - Robert L Hettich
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Mitchel J Doktycz
- UT-ORNL Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA.,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.,Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jennifer L Morrell-Falvey
- UT-ORNL Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA. .,Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA. .,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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10
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Yoon Y, Kim G, Noh MG, Park JH, Jang M, Fang S, Park H. Lactobacillus fermentum promotes adipose tissue oxidative phosphorylation to protect against diet-induced obesity. Exp Mol Med 2020; 52:1574-1586. [PMID: 32917958 PMCID: PMC8080655 DOI: 10.1038/s12276-020-00502-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/28/2020] [Accepted: 07/06/2020] [Indexed: 01/02/2023] Open
Abstract
The gut microbiota has pivotal roles in metabolic homeostasis and modulation of the intestinal environment. Notably, the administration of Lactobacillus spp. ameliorates diet-induced obesity in humans and mice. However, the mechanisms through which Lactobacillus spp. control host metabolic homeostasis remain unclear. Accordingly, in this study, we evaluated the physiological roles of Lactobacillus fermentum in controlling metabolic homeostasis in diet-induced obesity. Our results demonstrated that L. fermentum-potentiated oxidative phosphorylation in adipose tissue, resulting in increased energy expenditure to protect against diet-induced obesity. Indeed, oral administration of L. fermentum LM1016 markedly ameliorated glucose clearance and fatty liver in high-fat diet-fed mice. Moreover, administration of L. fermentum LM1016 markedly decreased inflammation and increased oxidative phosphorylation in gonadal white adipose tissue, as demonstrated by transcriptome analysis. Finally, metabolome analysis showed that metabolites derived from L. fermentum LM1016-attenuated adipocyte differentiation and inflammation in 3T3-L1 preadipocytes. These pronounced metabolic improvements suggested that the application of L. fermentum LM1016 could have clinical applications for the treatment of metabolic syndromes, such as diet-induced obesity.
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Affiliation(s)
- Youngmin Yoon
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | - Gihyeon Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | - Myung-Giun Noh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | | | - Mongjoo Jang
- Genome and Company, Pangyo-ro 255, Bundang-gu, Seoungnam, Korea
| | - Sungsoon Fang
- Severance Biomedical Science Institute, BK21 PLUS Project for Medical Science, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
| | - Hansoo Park
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea.
- Genome and Company, Pangyo-ro 255, Bundang-gu, Seoungnam, Korea.
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Dhasmana A, Uniyal S, Anukriti, Kashyap VK, Somvanshi P, Gupta M, Bhardwaj U, Jaggi M, Yallapu MM, Haque S, Chauhan SC. Topological and system-level protein interaction network (PIN) analyses to deduce molecular mechanism of curcumin. Sci Rep 2020; 10:12045. [PMID: 32694520 PMCID: PMC7374742 DOI: 10.1038/s41598-020-69011-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 06/12/2020] [Indexed: 12/14/2022] Open
Abstract
Curcumin is an important bioactive component of turmeric and also one of the important natural products, which has been investigated extensively. The precise mode of action of curcumin and its impact on system level protein networks are still not well studied. To identify the curcumin governed regulatory action on protein interaction network (PIN), an interectome was created based on 788 key proteins, extracted from PubMed literatures, and constructed by using STRING and Cytoscape programs. The PIN rewired by curcumin was a scale-free, extremely linked biological system. MCODE plug-in was used for sub-modulization analysis, wherein we identified 25 modules; ClueGo plug-in was used for the pathway’s enrichment analysis, wherein 37 enriched signalling pathways were obtained. Most of them were associated with human diseases groups, particularly carcinogenesis, inflammation, and infectious diseases. Finally, the analysis of topological characteristic like bottleneck, degree, GO term/pathways analysis, bio-kinetics simulation, molecular docking, and dynamics studies were performed for the selection of key regulatory proteins of curcumin-rewired PIN. The current findings deduce a precise molecular mechanism that curcumin might exert in the system. This comprehensive in-silico study will help to understand how curcumin induces its anti-cancerous, anti-inflammatory, and anti-microbial effects in the human body.
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Affiliation(s)
- Anupam Dhasmana
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA.,Department of Biosciences and Cancer Research Institute, Himalayan Institute of Medical Sciences, Swami Rama Himalayan University, Dehradun, India
| | - Swati Uniyal
- School of Biotechnology, Gautam Buddha University, Greater Noida, India
| | - Anukriti
- Department of Biosciences and Cancer Research Institute, Himalayan Institute of Medical Sciences, Swami Rama Himalayan University, Dehradun, India
| | - Vivek Kumar Kashyap
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Pallavi Somvanshi
- Department of Biotechnology, TERI School of Advanced Studies, 10, Institutional Area, Vasant Kunj,, New Delhi, India
| | - Meenu Gupta
- Department of Biosciences and Cancer Research Institute, Himalayan Institute of Medical Sciences, Swami Rama Himalayan University, Dehradun, India
| | - Uma Bhardwaj
- Department of Biosciences and Cancer Research Institute, Himalayan Institute of Medical Sciences, Swami Rama Himalayan University, Dehradun, India
| | - Meena Jaggi
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Murali M Yallapu
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, Saudi Arabia
| | - Subhash C Chauhan
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, Edinburg, TX, USA.
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Huang W, Hu H, Zhang Q, Wu X, Wei F, Yang F, Gan L, Wang N, Yang X, Guo AY. Regulatory networks in mechanotransduction reveal key genes in promoting cancer cell stemness and proliferation. Oncogene 2019; 38:6818-6834. [PMID: 31406247 PMCID: PMC6988105 DOI: 10.1038/s41388-019-0925-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 06/21/2019] [Accepted: 07/08/2019] [Indexed: 12/18/2022]
Abstract
Tumor-repopulating cells (TRCs) are cancer stem cell (CSC)-like cells with highly tumorigenic and self-renewing abilities, which were selected from tumor cells in soft three-dimensional (3D) fibrin gels with unidentified mechanisms. Here we evaluated the transcriptome alteration during TRCs generation in 3D culture and revealed that a variety of molecules related with integrin/membrane and stemness were continuously altered by mechanical environment. Some key regulators such as MYC/STAT3/hsa-miR-199a-5p, were changed in the TRCs generation. They regulated membrane genes and the downstream mechanotransduction pathways such as Hippo/WNT/TGF-β/PI3K-AKT pathways, thus further affecting the expression of downstream cancer-related genes. By integrating networks for membrane proteins, the WNT pathway and cancer-related genes, we identified key molecules in the selection of TRCs, such as ATF4, SLC3A2, CCT3, and hsa-miR-199a-5p. Silencing ATF4 or CCT3 inhibited the selection and growth of TRCs whereas reduction of SLC3A2 or hsa-miR-199a-5p promoted TRCs growth. Further studies showed that CCT3 promoted cell proliferation and stemness in vitro, while its suppression inhibited TRCs-induced tumor formation. We also contemplated CCT3 as a stemness-related gene. Our findings provide insights in the mechanism of TRCs selection through transcriptome analysis.
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Affiliation(s)
- Wei Huang
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Hui Hu
- Hubei Bioinformatics & Molecular Imaging Key Laboratory, Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Qiong Zhang
- Hubei Bioinformatics & Molecular Imaging Key Laboratory, Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Xian Wu
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Fuxiang Wei
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Fang Yang
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Lu Gan
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Ning Wang
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
- Department of Mechanical Science and Engineering, College of Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Xiangliang Yang
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China.
| | - An-Yuan Guo
- Hubei Bioinformatics & Molecular Imaging Key Laboratory, Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China.
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Chen W, Shu D, Chadwick VS. Inhibition of mitogen-induced murine lymphocyte proliferation by Helicobacter pylori cell-free extract. J Gastroenterol Hepatol 2000; 15:1000-6. [PMID: 11059928 DOI: 10.1046/j.1440-1746.2000.02286.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND AIMS Previous studies have shown that lysates of Helicobacter pylori inhibit mitogen-induced proliferation of human peripheral blood mononuclear cells. The objective of the present study was to determine whether H. pylori cell-free extract (HPCE) has similar effects on murine lymphoid cells and could, therefore, be used to further delineate the mechanisms of alteration of lymphocyte function by H. pylori. METHODS The HPCE was prepared from a H. pylori reference strain and from five clinical strains with varying status of cagA and vacA. Mouse splenic and mesenteric lymph node cells were cultured in microwell plates in the presence or absence of varying concentrations of HPCE (0.625-12.5 microg/mL). T cell mitogens were added into the culture 2 h later and the cells were cultured at 37 degrees C in 5% CO2 for a further 72 h. Cell proliferation was determined by a non-radioactive rapid dye assay and the percentage inhibition caused by HPCE was calculated. RESULTS Pre-exposure to HPCE significantly inhibited concanavalin A-induced proliferation of murine spleen and mesenteric lymph node cells (up to 100% inhibition; P < or = 0.01). The HPCE also inhibited lymphocyte proliferation stimulated by mitogens phorbol-myristate-acetate and ionomycin and by the anti-CD3epsilon monoclonal antibody (P < or = 0.05). The inhibition was dose-dependent, but independent of the presence of virulence genes cagA or vacA. Treatment of HPCE at 80 degrees C for 30 min, but not at 55 degrees C for 60 min, completely abolished its inhibitory action. The HPCE, pretreated with pronase E, proteinase K, trypsin, acid or alkali also completely lost its inhibitory effect (P < or = 0.01), while in contrast, treatment with carboxypeptidase and leucine aminopeptidase had no effect. CONCLUSION Helicobacter pylori produces heat-labile proteins or peptides that suppress T cell mitogen-induced proliferation of murine lymphoid cells in a similar manner to that observed with human peripheral blood mononuclear cells. The mouse cell culture system can, therefore, be used as a model to further study the mechanisms of action and antigen specificity of these immunomodulatory factors.
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Affiliation(s)
- W Chen
- Wakefield Gastroenterology Research Institute, Wakefield Hospital, Wellington, New Zealand.
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Chen PB, Davern LB, Katz J, Eldridge JH, Michalek SM. Host responses induced by co-infection with Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in a murine model. ORAL MICROBIOLOGY AND IMMUNOLOGY 1996; 11:274-81. [PMID: 9002881 DOI: 10.1111/j.1399-302x.1996.tb00181.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this study, evidence is presented that mixed infection with the periodontal pathogens Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans results in a synergistic effect in their pathogenicity and in their ability to induce humoral and cellular host responses. BALB/c mice were injected subcutaneously on the back with P. gingivalis ATCC 53977, A. actinomycetemocomitans 75 or a mixture of both bacteria. Samples of blood and fluid from abscesses formed at the site of injection (first degree) or distant from the injection site were collected for microbiologic analysis. Serum and spleens were obtained for evaluation of humoral and cellular responses to P. gingivalis and A actinomycetemocomitans. Mice injected with A. actinomycetemcomitans had first-degree lesions only, whereas mice injected with P. gingivalis and A. actinomycetemcomitans had lesions at first- and second-degree sites from which both bacterial species were isolated. A serum anti-P. gingivalis response was induced in P. gingivalis-injected mice, which was higher in mice injected with P. gingivalis and A. actinomycetemcomitans. This pattern was not seen in the anti-A, actinomycetemcomitans response. Lymphoproliferative responses to phytohemagglutinin, Escherichia coli lipopolysaccharide and P. gingivalis of spleen cells from infected mice were decreased, especially following co-infection. Furthermore, co-infection of mice resulted in the greatest decrease in the number of CD5+, especially CD4+ lymphocytes.
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Affiliation(s)
- P B Chen
- Department of Oral Biology, School of Dental Medicine, State University of New York at Buffalo, USA
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Matsui K, Arai T. Immunosuppression induced by Salmonella involves inhibition of tyrosine phosphorylation in murine T lymphocytes. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1993; 7:345-54. [PMID: 8136784 DOI: 10.1111/j.1574-695x.1993.tb00416.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
It is well known that facultative intracellular pathogens such as Salmonella suppress the host immune system. In the present study we attempted to clarify the mechanism responsible for the suppression of T-cell proliferation in mice infected with Salmonella typhimurium. The proliferation of murine spleen cells stimulated with a T-cell mitogen such as phytohemagglutinin (PHA) or concanavalin A (ConA) was significantly suppressed when the mice were infected with S. typhimurium, but not with Escherichia coli. The suppression of T-cell proliferation did not necessarily parallel the level of interleukin-2 (IL-2) secretion, and was not restored by treatment with a calcium ionophore, indomethacin or IL-2. Only phorbol 12-myristate-13 acetate (PMA), an activator of protein kinase C (PKC), caused a slight recovery of cell proliferation with an augmentation of IL-2 secretion. Furthermore, Western blotting using anti-phosphotyrosine antibodies showed that the mitogen-induced tyrosine phosphorylation of 120-, 106-, 94-, 76-, 68- and 57-kDa proteins in murine splenic T-cells was inhibited by S. typhimurium infection. Also, the inhibition of tyrosine phosphorylation was not restored by treatment with PMA. These results suggest that the suppression of T-cell proliferation induced by Salmonella infection may be regulated by inhibition of tyrosine phosphorylation in T-cells, although the inhibition is not associated with PKC activation and subsequent IL-2 secretion of T cells.
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Affiliation(s)
- K Matsui
- Department of Microbiology, Meiji College of Pharmacy, Tokyo, Japan
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Matsui K, Arai T. Inhibition of mitogen-induced proliferation of spleen lymphocytes is correlated with the induction of cell-mediated immunity in Salmonella infection in mice. FEMS Microbiol Lett 1993; 112:113-8. [PMID: 8405942 DOI: 10.1111/j.1574-6968.1993.tb06432.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The proliferation of murine spleen cells stimulated by a T-cell mitogen such as phytohemagglutinin (PHA) or concanavalin A (ConA) was significantly suppressed when the mice were immunized with either the viable cells or the sonicate of Salmonella typhimurium but not of Escherichia coli. The suppression of T-cell proliferation caused by the sonicate of S. typhimurium was completely restored by addition of phorbol 12-myristate-13-acetate (PMA), an activator of protein kinase C (PKC). Western blots using anti-phosphotyrosine antibodies showed that the mitogen-induced tyrosine phosphorylation of 120-, 106-, 94-, 76-, 68- and 57-kDa proteins in murine splenic T-cells was inhibited in the mice immunized with the viable cells but not the sonicate of S. typhimurium. These results suggest that the inhibition caused by the sonicate involves suppression of PKC activity, whilst that produced by viable cells involves down-regulation of tyrosine phosphorylation, and both inhibitions correlate with the induction of cell-mediated immunity in mice, as evidenced by the induction of delayed-type hypersensitivity reactions.
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Affiliation(s)
- K Matsui
- Department of Microbiology, Meiji College of Pharmacy, Tokyo, Japan
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Marco AJ, Domingo M, Prats M, Briones V, Pumarola M, Dominguez L. Pathogenesis of lymphoid lesions in murine experimental listeriosis. J Comp Pathol 1991; 105:1-15. [PMID: 1918447 DOI: 10.1016/s0021-9975(08)80057-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Adult female Swiss albino mice were infected intraperitoneally or subcutaneously with Listeria monocytogenes Serovar 4b or 1/2a and killed at intervals. Thymus, spleen, Peyer's patches and a variety of lymph nodes, including the jejunal (mesenteric), mediastinal, lumbar, mandibular and superficial inguinal, were examined by histopathology and by immunocytochemistry for detection of L. monocytogenes antigen. Similar results were obtained with both Serovars and by both routes of inoculation used. In the spleen, L. monocytogenes was detected, by immunoperoxidase staining, as soon as 4 h after inoculation, inside phagocytic cells located predominantly in the marginal zone of the white pulp. This was followed by inflammation, necrosis and depletion of lymphoid cells, which extended in extreme cases to the whole organ. Inflammatory lesions diminished progressively at 5 to 6 days after inoculation. In animals dying of the infection, a severe necrotizing splenitis was present. Depletion of lymphoid cells and inflammatory changes were widespread in the lymph nodes and to a lesser extent in the Peyer's patches. An extensive necrotizing lymphadenitis was the prominent lesion in severely affected nodes. Inflammatory lesions and detection of L. monocytogenes antigen started around the venules of high endothelium. A thymus depletion, not associated with the multiplication of bacteria in the organ, was also a constant feature of the infection. This study suggests that L. monocytogenes (1) is transported to the spleen and to the lymph nodes by phagocytes, entering the organs by the marginal sinus in the spleen and by the venules of high endothelium in the lymph nodes; (2) multiplies in these cells as well as in neutrophilic granulocytes (the latter rapidly migrate to the affected zones); and (3) induce a splenitis and lymphadenitis, involving predominantly T cell-dependent areas, with a necrotizing component in severe cases. From our observations it is concluded that infection of the lymphoid system is a major feature in the pathogenesis of murine listeriosis.
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Affiliation(s)
- A J Marco
- Dept. de Anatomía Patológica, Facultad de Veterinaria, Universidad Autónoma de Barcelona, Spain
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