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Fine, J.

Publications and source records attributed to Fine, J..

17 recordsLinked to original sources

Temperate Phage Shape Honey Bee Gut Microbiome Structure and Response to Antibiotic Treatment

Bacteriophage (phage) are hypothesized to play a significant role in modulating gut microbiomes. Yet, in vivo research examining the role of phage in gut ecosystems remains sparse, largely due to a lack of tractable model systems. Here, we use the honey bee (Apis mellifera) gut as a model to test the hypotheses that phage-bacteria interactions in the gut are temporally variable and that stress, in the form of antibiotics, can enhance phage killing of their bacterial hosts. First, we isolated and characterized a novel temperate phage which infects a bee-specific strain of Bifidobacterium. We then mono-colonized adult honey bees with this Bifidobacterium strain and tested how phage treatment impacts bacterial abundance over time. Next, using a series of in vitro and in vivo experiments, we examined how phage-bacteria interactions change in response to treatment with tetracycline, an antibiotic commonly used in commercial beekeeping. Finally, to probe the biological mechanisms underlying different phage-antibiotic synergies, we assayed how different classes of antibiotics impacted bacterial growth with and without phage infection. Our results indicate that a single temperate phage can both promote the ability of its Bifidobacterium host to colonize the gut, while also increasing host sensitivity to antibiotic treatment. Together, these findings demonstrate that environmental stressors can shift phage-bacteria interactions from mutualism to antagonism, highlighting the significance of phage in shaping how gut microbiomes respond to antibiotic or xenobiotic perturbation.

microbiology↗

An ancestral haplotype of P2RX5 yields a B-cell surface marker and a promising multi-lineage immunotherapy target

While CD19- and BCMA-directed immunotherapies have improved outcomes for B-lymphoid and plasma cell malignancies, frequent relapses with antigen loss/downregulation highlight the need for new targets. Here, using transcriptomic datasets and newly-developed monoclonal antibodies, we show that P2RX5, long considered a pseudogene in humans, encodes a stable protein in 80% of individuals of African descent carrying the ancestral haplotype. Like CD19, P2RX5 displays B-cell lineage-restricted expression in normal tissues. Unlike CD19, P2RX5 is expressed not only in B-cell neoplasms, but also in T-cell leukemia (T-ALL) and multiple myeloma (MM). We developed P2RX5-directed bispecific T-cell engagers and CAR T cells, which killed T-ALL cells with no evidence of T-cell fratricide. These agents were non-inferior to FDA-approved CD19- and BCMA-directed immunotherapeutics in cell culture and xenograft models of Burkitt lymphoma and MM, while maintaining potency against CD19- and BCMA-negative variants. Hence, P2RX5 is a unique multi-lineage target for frontline or salvage immunotherapy.

cancer biology↗

Mycobacterium tuberculosis-infected macrophages accumulate more nanoparticles

In response to the escalating threat of infectious diseases and the widespread emergence of antimicrobial-resistant strains, novel therapeutic strategies are being actively developed. Nanoparticle-based delivery systems have emerged as promising tools to improve the targeted administration of antimicrobials directly to sites of infection. In the context of pulmonary infections, aerosolized nanocarriers can enhance local biodistribution while minimizing systemic exposure and associated side effects. In this study, we demonstrate that following pulmonary administration in Mycobacterium tuberculosis-infected mice, poly(lactic-co-glycolic acid) (PLGA) nanoparticles are broadly distributed throughout the lungs and preferentially interact with alveolar macrophages--the primary host cells of the pathogen. Remarkably, infected macrophages internalize significantly more nanoparticles than uninfected cells independently of the virulence and viability of the bacteria. Using transcriptomic analysis, we uncovered a list of 21 commonly modulated genes that may be responsible for this phenotype. Collectively, our findings reveal a striking feature of nanoparticles: their capacity to selectively accumulate in infected cells, offering a powerful mechanism to enhance antimicrobial delivery precisely where it is most needed.

cell biology↗

De novo design of miniprotein agonists and antagonists targeting G protein-coupled receptors

G protein-coupled receptors (GPCRs) play key roles in physiology and are central targets for drug discovery and development, but the design of protein agonists and antagonists has been challenging as GPCRs are integral membrane proteins and conformationally dynamic. Here we describe computational de novo design methods and a high throughput "receptor diversion" microscopy-based screen for generating GPCR binding miniproteins with high affinity, potency and selectivity, and the use of these methods to generate agonists for MRGPRX1, NK1R and CCR5, as well as antagonists for CXCR4, CCR5, OXTR, GLP1R, GIPR, GCGR, PTH1R and CGRPR.. Cryo-electron microscopy data reveals atomic-level agreement between designed and experimentally determined structures for CGRPR- and CXCR4-bound antagonists and MRGPRX1-bound agonists. Our de novo design and screening approach opens new frontiers in GPCR drug discovery and development.

bioengineering↗

Neuronal cell adhesion molecule (NRCAM) variant defined by microexon skipping is an essential, antigenically distinct, and targetable surface proteoform in high-grade glioma

To overcome the paucity of known tumor-specific surface antigens in pediatric high-grade glioma (pHGG), we contrasted splicing patterns in pHGGs and normal brain samples. Among alternative splicing events affecting extracellular protein domains, the most pervasive alteration was the skipping of [≤]30 nucleotide-long exons. Several of these skipped microexons mapped to L1-IgCAM family members, such as NRCAM. Bulk and single-nuclei short- and long-read RNA-seq revealed uniform skipping of NRCAM microexons 5 and 19 in virtually every pHGG sample. Importantly, the {Delta}ex5{Delta}ex19 (but not the full-length) NRCAM proteoform was essential for pHGG cell migration and invasion in vitro and tumor growth in vivo. We developed a monoclonal antibody selective for {Delta}ex5{Delta}ex19 NRCAM and demonstrated that "painting" of pHGG cells with this antibody enables killing by T cells armed with an FcRI-based universal immune receptor. Thus, pHGG-specific NRCAM and possibly other L1-IgCAM proteoforms are promising and highly selective targets for adoptive immunotherapies.

cancer biology↗

Common viral infections inhibit egg laying in honey bee queens and are linked to premature supersedure

With their long lives and extreme reproductive output, social insect queens have escaped the classic trade-off between fecundity and lifespan but evidence for a trade-off between fecundity and immunity has been inconclusive. This is in part because pathogenic effects are seldom decoupled from effects of immune induction. We conducted parallel, blind virus infection experiments in the laboratory and in the field to interrogate the idea of a reproductive immunity trade-off and better understand how these ubiquitous honey bee stressors affect queen health. We found that queens injected with infectious virus had smaller ovaries and were less likely to recommence egg-laying than controls, while queens injected with UV-inactivated virus displayed an intermediate phenotype. In the field, heavily infected queens had smaller ovaries and infection was a meaningful predictor of whether supersedure cells were observed in the colony. Immune responses in queens receiving live virus were similar to queens receiving inactivated virus, and several of the same immune proteins were negatively associated with ovary mass in the field. This work solidifies the relationship between virus infection and symptoms associated with queen failure and suggests that a reproductive-immunity trade-off is partially, but not wholly responsible for these effects.

zoology↗

Temporal interference electrical neurostimulation yields fMRI BOLD activation in humans

Temporal interference electrical neurostimulation (TI) is a relatively new method of non-invasive neurostimulation that may be able to stimulate deep brain regions without stimulating the overlying superficial regions. Despite studies in rodents, almost no studies have investigated its effects on human brain activity along with safety and tolerability profiles. We performed simultaneous TI stimulation and fMRI to investigate the effects of TI on human BOLD signals. Here we show that TI can induce increased BOLD activation in humans, with good safety and tolerability profiles. We also show the limits of spatial precision and explore the nature and causes of additional off target effects. TI may be a promising approach for addressing questions about the causal role of deep brain structures in human cognition and may also afford new clinical treatments.

neuroscience↗

Amyloid β Induces Lipid Droplet-Mediated Microglial Dysfunction in Alzheimer's Disease

Several microglia-expressed genes have emerged as top risk variants for Alzheimers disease (AD). Impaired microglial phagocytosis is one of the main proposed outcomes by which these AD-risk genes may contribute to neurodegeneration, but the mechanisms translating genetic association to cellular dysfunction remain unknown. Here we show that microglia form lipid droplets (LDs) upon exposure to amyloid-beta (A{beta}), and that their LD load increases with proximity to amyloid plaques in brains from human patients and the AD mouse model 5xFAD. LD formation is dependent on age and disease progression and is prominent in the hippocampus in mice and humans. Despite differences in microglial LD load between brain regions and sexes in mice, LD-laden microglia exhibited a deficit in A{beta} phagocytosis. Unbiased lipidomic analysis identified a decrease in free fatty acids (FFAs) and a parallel increase in triacylglycerols (TGs) as the key metabolic transition underlying LD formation. DGAT2, a key enzyme for converting FFAs to TGs, promotes microglial LD formation and is increased in 5xFAD and human AD brains. Inhibition or degradation of DGAT2 improved microglial uptake of A{beta} and drastically reduced plaque load in 5xFAD mice, respectively. These findings identify a new lipid-mediated mechanism underlying microglial dysfunction that could become a novel therapeutic target for AD.

neuroscience↗

Imbalance between IL-36 receptor agonist and antagonist drives neutrophilic inflammation in COPD

Current treatments fail to modify the underlying pathophysiology and disease progression of chronic obstructive pulmonary disease (COPD), necessitating novel therapies. Here, we show that COPD patients have increased IL-36{gamma} and decreased IL-36 receptor antagonist (IL-36Ra) in bronchoalveolar and nasal fluid compared to control subjects. IL-36{gamma} is derived mainly from small airway epithelial cells (SAEC) and further induced by a viral mimetic, whereas IL-36RA is derived from macrophages. IL-36{gamma} stimulates release of the neutrophil chemoattractants CXCL1 and CXCL8, as well as elastolytic matrix metalloproteinases (MMPs) from small airway fibroblasts (SAF). Proteases released from COPD neutrophils cleave and activate IL-36{gamma} thereby perpetuating IL-36 inflammation. Transfer of culture media from SAEC to SAF stimulated release of CXCL1, that was inhibited by exogenous IL-36RA. The use of a therapeutic antibody that inhibits binding to the IL-36 receptor (IL-36R) attenuated IL-36{gamma} driven inflammation and cellular cross talk. We have demonstrated a novel mechanism for the amplification and propagation of neutrophilic inflammation in COPD and that blocking this cytokine family via a IL-36R neutralising antibody could be a promising new therapeutic strategy in the treatment of COPD.

cell biology↗

Functional characterization of RebL1 highlights the evolutionary conservation of oncogenic activities of the RBBP4/7 orthologue in Tetrahymena thermophila

Retinoblastoma-binding proteins 4 and 7 (RBBP4 and RBBP7) are two highly homologous human histone chaperones. They function in epigenetic regulation as subunits of multiple chromatin-related complexes and have been implicated in numerous cancers. Due to their overlapping functions, our understanding of RBBP4 and 7, particularly outside of Opisthokonts, has remained limited. Here, we report that in the ciliate protozoan Tetrahymena thermophila a single orthologue of human RBBP4 and 7 proteins, RebL1, physically interacts with histone H4 and functions in multiple epigenetic regulatory pathways. Functional proteomics identified conserved functional links associated with Tetrahymena RebL1 protein as well as human RBBP4 and 7. We found that putative subunits of multiple chromatin-related complexes including CAF1, Hat1, Rpd3, and MuvB, co-purified with RebL1 during Tetrahymena growth and conjugation. Iterative proteomics analyses revealed that the cell cycle regulatory MuvB-complex in Tetrahymena is composed of at least five subunits including evolutionarily conserved Lin54, Lin9 and RebL1 proteins. Genome-wide analyses indicated that RebL1 and Lin54 (Anqa1) bind within genic and intergenic regions. Moreover, Anqa1 targets primarily promoter regions suggesting a role for Tetrahymena MuvB in transcription regulation. RebL1 depletion decreased cellular viability and altered the expression of selected targets. Consistent with observations in glioblastoma tumors, RebL1 depletion suppressed DNA repair protein Rad51 in Tetrahymena, thus underscoring the evolutionarily conserved functions of RBBP4/7 proteins. Our results suggest the essentiality of RebL1 functions in multiple epigenetic regulatory complexes in which it impacts transcription regulation and cellular viability.

molecular biology↗

Integration of Biodynamic Imaging and RNA-seq predicts chemotherapy response in canine diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a common, aggressive cancer of notorious genotypic and phenotypic heterogeneity. A major challenge is predicting response to drug treatment, which has typically been done using genomic tools alone with little success. A novel method that incorporates phenotypic profiling for predicting the effectiveness of therapy for individual patients is desperately needed. BioDynamic Imaging (BDI) is a technique for measuring time-dependent fluctuations in back-scattered light through living tumor tissues to identify critical changes in intracellular dynamics that are associated with phenotypic response to drugs. In this study, BDI and RNA sequencing (RNA-seq) data were collected on tumor samples from dogs with naturally occurring DLBCL, an animal model of increasingly recognized relevance to the human disease. BDI and RNA-seq data were combined to identify correlations between gene co-expression modules and linear combinations of biomarkers to provide biological mechanistic interpretations of BDI biomarkers. Using regularized multivariate logistic regression, we combined RNA-seq and BDI data to develop a novel model to accurately classify the clinical response of canine DLBCL to combination chemotherapy (i.e. CHOP). Our model incorporates data on the expression of 4 genes and 3 BDI-derived phenotypic biomarkers, capturing changes in transcription, microtubule related processes, and apoptosis. This pilot study suggests that the combination of multi-scale transcriptomic and phenotypic data can identify patients that respond to a given treatment a priori in a disease that has been difficult to treat. Our work provides an important framework for future development of strategies and treatments in precision cancer medicine.

cancer biology↗

DUBS: A Framework for Developing Directory of Useful Benchmarking Sets for Virtual Screening

Benchmarking is a crucial step in evaluating virtual screening methods for drug discovery. One major issue that arises among benchmarking datasets is a lack of a standardized format for representing the protein and ligand structures used to benchmark the virtual screening method. To address this, we introduce the Directory of Useful Benchmarking Sets (DUBS) framework, as a simple and flexible tool to rapidly created benchmarking sets using the protein databank. DUBS uses a simple input text based format along with the Lemon data mining framework to efficiently access and organize data to protein databank and output commonly used inputs for virtual screening software. The simple input format used by DUBS allows users to define their own benchmarking datasets and access the corresponding information directly from the software package. Currently, it only takes DUBS less than 2 minutes to create a benchmark using this format. Since DUBS uses a simple python script, users can easily modify to create more complex benchmarks. We hope that DUBS will be a useful community resource to provide a standardized representation for benchmarking datasets in virtual screening.

bioinformatics↗

Breaking a Strong Amide Bond: Structure and Properties of Dimethylformamidase.

Dimethylformamidase (DMFase) breaks down the human-made synthetic solvent N,N-dimethyl formamide(DMF) used extensively in industry(1). DMF is not known to exist in nature and was first synthesized in 1893. In spite of the recent origin of DMF, certain bacterial species such as Paracoccus, Pseudomonas, and Alcaligenes have evolved pathways to breakdown DMF and use them as carbon and nitrogen source for growth(2, 3). The work presented here provides a molecular basis for the ability of DMFase from Paracoccus to function in exacting conditions of high solvent concentrations, temperature and ionic strength to catalyze the hydrolysis of a stable amide bond. The structure reveals a multimeric complex of the 2{beta}2 type or (2{beta}2)2 type. One of the three domains of the large subunit and the small subunit are hitherto undescribed folds and as yet of unknown evolutionary origin. The active site is made of a distinctive mononuclear iron that is coordinated by two tyrosine residues and a glutamic acid residue. The hydrolytic cleavage of the amide bond is catalyzed at the Fe3+ site with a proximal glutamate probably acting as the base. The change in the quaternary structure is salt dependent with high salt resulting in the larger oligomeric state. Kinetic characterization reveals an enzyme that shows cooperativity between subunits and the structure provides clues on the interconnection between the active sites. Significance StatementN,N-dimethyl formamide(DMF) is a commonly used industrial solvent that was first synthesized in 1893. The properties that make DMF a highly desired solvent also makes it a difficult compound to breakdown. Yet, certain bacteria have evolved to survive in environments polluted by DMF and have enzymes that breakdown DMF and use it as their carbon and nitrogen source. The molecular structure of the enzyme that breaks down the stable amide bond in these bacteria, reveals two new protein folds and a unique mononuclear iron active site. The work reported here provides the structural and biochemical framework to query the evolutionary origins of the protein, as well as in engineering this enzyme for use in bioremediation of a human made toxic solvent.

biochemistry↗

Generalized Multi-SNP Mediation Intersection-Union Test

SO_SCPLOWUMMARYC_SCPLOWTo elucidate the molecular mechanisms underlying genetic variants identified from genome-wide association studies (GWAS) for a variety of phenotypic traits encompassing binary, continuous, count, and survival outcomes, we propose a novel and flexible method to test for mediation that can simultaneously accommodate multiple genetic variants and different types of outcome variables. Specifically, we employ the intersection-union test approach combined with likelihood ratio test to detect mediation effect of multiple genetic variants via some mediator (for example, the expression of a neighboring gene) on outcome. We fit high-dimensional generalized linear mixed models under the mediation framework, separately under the null and alternative hypothesis. We leverage Laplace approximation to compute the marginal likelihood of outcome and use coordinate descent algorithm to estimate corresponding parameters. Our extensive simulations demonstrate the validity of our proposed method and substantial, up to 97%, power gains over alternative methods. Applications to real data for the study of Chlamydia trachomatis infection further showcase advantages of our method. We believe our proposed method will be of value and general interest in this post-GWAS era to disentangle the potential causal mechanism from DNA to phenotype for new drug discovery and personalized medicine.

genetics↗

Single-cell analysis of Crohn’s disease lesions identifies a pathogenic cellular module associated with resistance to anti-TNF therapy

Clinical benefits to cytokine blockade in ileal Crohns disease (iCD) have been limited to a subset of patients. Whether cellular and molecular heterogeneity contributes to variability in treatment responses has been unclear. Using single cell technologies combining scRNAseq, CyTOF and multiplex tissue imaging, we mapped the cellular landscape of inflamed ileum lesions, adjacent non-inflamed ileum and matched circulating blood cells of iCD patients. In inflamed tissues, we identified a pathogenic module characterized by an inflammatory mononuclear phagocyte (Inf.MNP)-associated cellular response organized around inflammatory macrophages and mature dendritic cells in a subset of iCD patients. We confirmed the Inf.MNP-associated cellular response in 4 independent iCD cohorts (n=441) and showed that presence of this pathogenic module at diagnosis correlated with primary resistance to anti-TNF therapy. Single cell mapping of iCD tissues identifies a complex cellular signature of anti-TNF resistance thereby revealing novel biomarkers of treatment response and tailored therapeutic opportunities.

immunology↗

SMUT: multi-SNP Mediation intersection-Union Test

Tens of thousands of reproducibly identified GWAS (Genome-Wide Association Studies) variants, with the vast majority falling in non-coding regions resulting in no eventual protein products, call urgently for mechanistic interpretations. Although numerous methods exist, there are few, if any methods, for simultaneously testing the mediation effects of multiple correlated SNPs via some mediator (for example, the expression of a gene in the neighborhood) on phenotypic outcome. We propose SMUT, multi-SNP Mediation intersection-Union Test to fill in this methodological gap. Our extensive simulations demonstrate the validity of SMUT as well as substantial, up to 92%, power gains over alternative methods. In addition, SMUT confirmed known mediators in a real dataset of Finns for plasma adiponectin level, which were missed by many alternative methods. We believe SMUT will become a useful tool to generate mechanistic hypotheses underlying GWAS variants, facilitating functional follow-up. The R package SMUT is publicly available from CRAN at https://CRAN.R-project.org/package=SMUT.

genetics↗

Lemon: a modern C++ tool for the rapid development of structural benchmarking datasets

MotivationThe protein data bank (PDB) currently holds over 140,000 biomolecular structures and continues to release new structures on a weekly basis. The PDB is an essential resource to the structural bioinformatics community to develop software that mine, use, categorize, and analyze such data. New computational biology methods are evaluated using custom benchmarking sets derived as subsets of 3D experimentally determined structures and structural features from the PDB. Currently, such benchmarking features are manually curated with custom scripts in a non-standardized manner that results in slow distribution and updates with new experimental structures. Finally, there is a scarcity of standardized tools to rapidly query 3D descriptors of the entire PDB. ApproachOur solution is the Lemon framework, a C++11 library with Python bindings, which provides a consistent workflow methodology for selecting biomolecular interactions based on user criterion and computing desired 3D structural features. This framework can parse and characterize the entire PDB in less than ten minutes on modern, multithreaded hardware. The speed in parsing is obtained by using the recently developed MacroMolecule Transmission Format (MMTF) to reduce the computational cost of reading text-based PDB files. The use of C++ lambda functions and Python binds provide extensive flexibility for analysis and categorization of the PDB by allowing the user to write custom functions to suite their objective. We think Lemon will become a one-stop-shop to quickly mine the entire PDB to generate desired structural biology features. The Lemon software is available as a C++ header library along with example functions at https://github.com/chopralab/lemon.

bioinformatics↗