Project description:Microglia are innate immune cells of the brain that perform phagocytic and inflammatory functions in disease conditions. Transcriptomic studies of acutely-isolated microglia have provided novel insights into their molecular and functional diversity in homeostatic and neurodegenerative disease states. State-of-the-art mass spectrometric methods can comprehensively characterize proteomic alterations in microglia in neurodegenerative disorders, potentially providing novel functionally-relevant molecular insights that are not provided by transcriptomics. However, proteomic profiling of adult primary microglia in neurodegenerative disease conditions has not been performed. We performed quantitative proteomic analyses of purified CD11b+ acutely-isolated microglia adult mice in normal, acute neuroinflammatory (LPS-treatment) and chronic neurodegenerative states (5xFAD model of Alzheimer’s disease [AD]) using tandem mass tag mass spectrometry. Differential expression analyses were performed to characterize specific microglial proteomic changes in 5xFAD mice and identify overlap with LPS-induced pro-inflammatory changes. Our results were also contrasted with existing proteomic data from wild-type mouse microglia and from existing microglial transcriptomic data from wild-type and 5xFAD mice. Neuropathological validation studies of select proteins were performed in human AD and 5xFAD brains. Of 4,133 proteins identified, 187 microglial proteins were differentially expressed in the 5xFAD mouse model of AD pathology, including proteins with previously known (Apoe, Clu and Htra1) as well as previously unreported relevance to AD biology (Cotl1 and Hexb). Proteins upregulated in 5xFAD microglia shared significant overlap with pro-inflammatory changes observed in LPS-treated mice. Several proteins increased in human AD brain were also upregulated by 5xFAD microglia (Aβ peptide, Apoe, Htra1, Cotl1 and Clu). Cotl1 was identified as a novel microglia-specific marker with increased expression and strong association with AD neuropathology. Apoe protein was also detected within plaque-associated microglia in which Apoe and Aβ were highly co-localized suggesting a role for Apoe in phagocytic clearance of Aβ. We report the first comprehensive comparative proteomic study of adult mouse microglia derived from acute neuroinflammatory and AD models, representing a valuable resource to the neuroscience research community. We highlight shared and unique microglial proteomic changes in acute neuroinflammatory, aging and AD mouse models in addition to identifying novel roles for microglial proteins in human neurodegeneration.
Project description:Introduction Aminoacyl tRNA-synthetases are ubiquitously expressed enzymes that attach amino acids to their cognate tRNA molecule. Mutations in several of the aminoacyl tRNA-syntheases are described to cause peripheral neuropathy, i.e. AARS1, GARS1, HARS1, YARS1 and WARS1. The Alanyl-tRNA Synthetase (AARS) is encoded by the AARS1. Bi-allelic mutations have been described responsible for epileptic encephalopathy with persistent myelination defect, while mutation in a single allele cause Charcot-Marie-Tooth disease type 2 (CMT2). Do date it is uncertain how a single AARS1 mutation cause tissue specific neuropathy. Methods The AARS1 was sequenced by next-generation sequencing in probands. Family members were examined by Sanger sequencing. Blood samples from affected and healthy controls were used for quantitative RNA analysis, biochemical analysis of alanine, and proteomics. Results Three Norwegian CMT2 families carried the same novel heterozygous AARS1 variant (NM_001605.2:c.976C>T p.(Arg326Trp)). The three families consisted of in total 17 genetically examined family members, of which 11 individuals carried the AARS1 variant and six unaffected individuals did not carry the variant. All individuals carrying the AARS1 variant presented with a mild to moderately severe CMT2 phenotype with adult onset, except a man age 91 years (reported by his son). Label-free quantitative proteomic analysis of four affected individuals pointed towards an effect on the immune system, comprising proteins known to represent components of systemic response to chronic injury and inflammation. Interestingly, a wide-spread impact on mitochondrial dysfunction was identified. Specifically, the oxidative phosphorylation complexes I, IV and V were highly downregulated. Conclusion Three Norwegian CMT2 families with an AARS1 variant, suggests mitochondrial dysfunction in AARS1 neuropathy.
Project description:This pilot study enrolled 9 GWI (Gulf War Illness) cases identified from the Department of Veterans Affairs GWI registry, and 11 sedentary control veterans who had not been deployed to the Persian Gulf and were matched to cases by sex, body mass index (BMI) and age.<br>We exposed GWI patients and matched controls to an exercise challenge to explore differences in immune cell function measured by classic immune assays and gene expression profiling.
Project description:Immune activation in people living with HIV on anti-retroviral therapy is associated with increased risk of morbidity and mortality, but the underlying mechanisms are poorly understood. To identify whether perturbation of immunological pathways persist at systems level, we compared genome-wide whole blood transcriptomes from 26 people living with HIV on long-term anti-retroviral therapy with 12 HIV-negative healthy controls. All participants were Caucasian male adults recruited from London, UK. People living with HIV were on anti-retroviral therapy for a median of 8.5 years (interquartile range 3-16 years). They had undetectable plasma HIV viral load (<40 copies/ml) and median circulating CD4 counts of 703 cells/µl (interquartile range 491-841 cells/µl).
Project description:Recent technological advances have made transcriptome sequencing (RNA-seq) possible in cells with low RNA copy number including platelets. Resulting studies have used RNA-seq in platelets isolated from healthy individuals to characterize the platelet transcriptome. However, platelets, possibly through gene expression changes, contribute to the etiology of and response to cardiovascular disease and events. To address this, we performed the largest human platelet RNA-seq analysis to date in 34 platelet samples: 16 ST-segment elevation myocardial infarction (STEMI), 16 non-STEMI (NSTEMI), and 2 controls. RNA-seq of platelet samples from 34 individuals: 16 with ST-elevation myocardial infarction (STEMI), 16 with non-STEMI, and 2 non-myocardial infarction controls
Project description:Claims for exceptional preservation of biomolecules in the fossil record are contested. Here we demonstrate the role of surface stabilisation in significantly prolonging protein sequence survival to ~3.8 million years. The intracrystalline environment of calcite ostrich (Struthionidae) eggshell encapsulates uterine proteins and molecular dynamics simulations of struthiocalcin-1 & -2, the dominant proteins within the eggshell, reveal that they bind to the mineral surface in distinct domains. By ~3.8 million years the struthiocalcin-1 domain with the lowest calculated binding energy is selectively preserved in eggshell samples from equatorial Africa. Sequence survival is explained by entropy loss of the peptide and water, lowering the effective temperature of the local environment at the peptide mineral interface.
Project description:Subjects underwent endothelial testing and blood sampling at baseline and after 3 months of exercise training. Microarray and flow cytometry-based characterization of cells from an endothelial progeniator colony assay was consistent with T lymphocytes, but not endothelial cells. Experiment Overall Design: blood samples from 12 healthy subjects at baseline (A) and after 3 months (B) of exercise.