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Goodwin, M.

Publications and source records attributed to Goodwin, M..

8 recordsLinked to original sources

The Synthetic Epitope Atlas: High-Throughput Design and Validation of De Novo Antibody-Antigen Complexes

AO_SCPLOWBSTRACTC_SCPLOWDe novo antibody design models lack sufficient training data to reliably generalize. We demonstrate scalable generation of structural training data for machine learning-driven antibody design by linking in silico designs of antibody-antigen complexes to high-throughput experimental binding validation. Using AlphaSeq, a yeast-based platform for measuring protein binding affinities, we measure the affinity and specificity of thousands of de novo "synthetic epitope proteins" (SEPs) designed to bind to VHHs. The resulting Synthetic Epitope Atlas (SEPIA) pairs over 26 million on- and off-target affinity measurements with computationally designed VHH-SEP "pseudo-structures." We validate strong, specific binding for 1,161 pseudo-structures and >75,000 VHH and SEP mutational variants. We show that these pseudo-structures complement existing structural databases and enable ML models to outperform confidence metrics commonly used to rank de novo antibody designs. Taken together, SEPIA establishes a scalable framework for improving de novo antibody design by augmenting sparse structural data with large-scale experimental binding data.

synthetic biology↗

Age-related increases in PDE11A4 protein expression trigger liquid:liquid phase separation (LLPS) of the enzyme that can be reversed by PDE11A4 small molecules inhibitors

PDE11A is a little-studied phosphodiesterase sub-family that breaks down cAMP/cGMP, with the PDE11A4 isoform being enriched in the memory-related brain region called the hippocampus. Age-related increases in PDE11A expression occur in human and rodent hippocampus and cause age-related cognitive decline of social memories. Interestingly, the age-related increase in PDE11A4 protein ectopically accumulates in spherical clusters that group together in the brain to form linear filamentous patterns termed "ghost axons." The biophysical/physiochemical mechanisms underlying this age-related clustering of PDE11A4 are not yet known. As such, we determine here if age-related clustering of PDE11A4 may reflect liquid:liquid phase separation (LLPS), and if PDE11A inhibitors being developed for age-related cognitive decline can reverse this biomolecular condensation. We found that human and mouse PDE11A4 exhibit several LLPS-promoting sequence features including intrinsically disordered regions, non-covalent pi-pi interactions, and prion-like domains, with multiple bioinformatic tools predicting PDE11A4 undergoes LLPS. Consistent with these predictions, age-related PDE11A4 clusters were non-membrane bound spherical droplets that progressively fuse over time in a concentration-dependent manner. 5 different PDE11 inhibitors (tadalafil, BC11-38, SMQ-02-57, SMQ-03-30 and SMQ-03-20) across 3 scaffolds reversed PDE11A4 LLPS (a.k.a. remixing) in hippocampal HT22 cells, with PDE11A4 droplets reforming (a.k.a. de-mixing) following a 5-hour washout of low but not high concentrations of these compounds. Strikingly, a single oral administration of 30 mg/kg SMQ-03-20 substantially reduced the presence of PDE11A4 ghost axon in the aged mouse brain. Thus, PDE11A4 exhibits 4 defining criteria of LLPS, and PDE11A small molecule inhibitors reverse this age-related phenotype both in vitro and in vivo.

neuroscience↗

Environmental sphagnum-associated fungi target thiol homeostasis to compete with Mycobacterium tuberculosis.

Mycobacterial species in nature are found in abundance in sphagnum peat bogs where they compete for nutrients with a variety of microorganisms including fungi. We screened a collection of fungi isolated from sphagnum bogs by co-culture with Mycobacterium tuberculosis (Mtb) to look for inducible expression of antitubercular agents and identified five fungi that produced cidal antitubercular agents upon exposure to live Mtb. Whole genome sequencing of these fungi followed by fungal RNAseq after Mtb exposure allowed us to identify biosynthetic gene clusters induced by co-culture. Three of these fungi induced expression of patulin, one induced citrinin expression and one induced the production of nidulalin A. The biosynthetic gene clusters for patulin and citrinin have been previously described but the genes involved in nidulalin A production have not been described before. All three of these potent electrophiles react with thiols and treatment of Mtb cells with these agents followed by Mtb RNAseq showed that these natural products all induce profound thiol stress suggesting a rapid depletion of mycothiol. The induction of thiol-reactive mycotoxins through three different systems in response to exposure to Mtb suggests that fungi have identified this as a highly vulnerable target in a similar microenvironment to that of the caseous human lesion.

microbiology↗

A highly conserved lipase deacylates oxidized phospholipids and ameliorates acute lung injury

Oxidized phospholipids have diverse biological activities, many of which can be pathological, yet how they are inactivated in vivo is not fully understood. Here we present evidence that a previously unsuspected host lipase, acyloxyacyl hydrolase (AOAH), can play a significant role in reducing the pro-inflammatory activities of two prominent products of phospholipid oxidation, 1-palmitoyl-2-glutaryl-sn-glycero-3- phosphocholine (PGPC) and 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC). AOAH removed the sn-2 and sn-1 acyl chains from both lipids and reduced their ability to induce macrophage inflammasome activation and cell death in vitro and acute lung injury in vivo. In addition to transforming Gram-negative bacterial lipopolysaccharide from stimulus to inhibitor, its most studied activity, AOAH can inactivate these important danger-associated molecular pattern (DAMP) molecules and reduce tissue inflammation and cell death.

immunology↗

HCMV glycoprotein B nucleoside-modified mRNA vaccine elicits antibody responses with greater durability and breadth than MF59-adjuvanted gB protein immunization

A vaccine to prevent maternal acquisition of human cytomegalovirus (HCMV) during pregnancy is a primary strategy to reduce the incidence of congenital disease. Similarly, vaccination of transplant recipients against HCMV has been proposed to prevent transplant-associated HCMV morbidity. The MF59-adjuvanted glycoprotein B protein subunit vaccine (gB/MF59) is the most efficacious tested to-date for both indications. We previously identified that gB/MF59 vaccination elicited poor neutralizing antibody responses and an immunodominant response against gB antigenic domain 3 (AD-3). Thus, we sought to test novel gB vaccines to improve functional antibody responses and reduce AD-3 immunodominance. Groups of juvenile New Zealand White rabbits were administered 3 sequential doses of full-length gB protein with an MF59-like squalene adjuvant (analogous to clinically-tested vaccine), gB ectodomain protein (lacking AD-3) with squalene adjuvant, or lipid nanoparticle (LNP)-packaged nucleoside-modified mRNA encoding full-length gB. The AD-3 immunodominant IgG response following human gB/MF59 vaccination was closely mimicked in rabbits, with 78% of binding antibodies directed against this region in the full-length gB protein group compared to 1% and 46% in the ectodomain and mRNA-LNP-vaccinated groups, respectively. All vaccines were highly immunogenic with similar kinetics and comparable peak gB-binding and functional antibody responses. Although gB ectodomain subunit vaccination reduced targeting of non-neutralizing epitope AD-3, it did not improve vaccine-elicited neutralizing or non-neutralizing antibody functions. gB nucleoside-modified mRNA-LNP-immunized rabbits exhibited enhanced durability of IgG binding to soluble and cell membrane-associated gB protein as well as HCMV-neutralizing function. Furthermore, the gB mRNA-LNP vaccine enhanced breadth of IgG binding responses against discrete gB peptide residues. Finally, low-magnitude gB-specific T cell activity was observed in the full-length gB protein and mRNA-LNP vaccine groups, though not in ectodomain-vaccinated rabbits. Altogether, these data suggest that the gB mRNA-LNP vaccine candidate, aiming to improve upon the partial efficacy of gB/MF59 vaccination, should be further evaluated in preclinical models.\n\nAuthor summaryHuman cytomegalovirus (HCMV) is the most common infectious cause of infant birth defects, resulting in permanent neurologic disability for one newborn child every hour in the United States. Furthermore, this virus causes significant morbidity and mortality in immune-suppressed transplant recipients. After more than a half century of research and development, we remain without a clinically-licensed vaccine or therapeutic to reduce the burden of HCMV-associated disease. In this study, we sought to improve upon the glycoprotein B protein vaccine (gB/MF59), the most efficacious HCMV vaccine evaluated in clinical trial, via targeted modifications to either the protein structure or vaccine formulation. An attempt to alter the protein structure to focus the immune response on vulnerable epitopes ( gB ectodomain) had little effect on the quality or function of the vaccine-elicited antibodies. However, a novel vaccine platform, nucleoside-modified mRNA formulated in lipid nanoparticles, increased the durability and breadth of vaccine-elicited immune responses. We propose that an mRNA-based gB vaccine may ultimately prove more efficacious than the gB/MF59 vaccine and should be further evaluated for its ability to elicit antiviral immune factors that can prevent both infant and transplant-associated disease caused by HCMV infection.

immunology↗

The effect of pre-analytical conditions on blood metabolomics in epidemiological studies

BackgroundSerum and plasma are commonly used biofluids for large-scale metabolomic-epidemiology studies. Their metabolomic profile is susceptible to changes due to variability in pre-analytical conditions and the impact of this is unclear.\n\nMethodsParticipant-matched EDTA-plasma and serum samples were collected from 37 non-fasting volunteers and profiled using a targeted nuclear magnetic resonance (NMR) metabolomics platform (N=151 traits). Metabolic concentrations were compared between reference (pre-storage: 4{degrees}C, 1.5h; post-storage: no sample preparation or NMR-analysis delays) and four, pre-storage, blood processing conditions, where samples were incubated at (i) 4{degrees}C, 24h; (ii) 4{degrees}C, 48h; (iii) 21{degrees}C, 24h; (iv) 21{degrees}C, 48h, before centrifugation; and two, post-storage, sample processing conditions in which samples (i) thawed overnight, then left for 24h before addition of sodium buffer followed by immediate NMR analysis; (ii) thawed overnight, addition of sodium buffer, then left for 24h before profiling. Linear regression models with random-intercepts were used to assess the impact of these six pre-analytical conditions on EDTA-plasma/serum metabolome.\n\nResultsFatty acids, beta-hydroxybutyrate, glycoprotein-acetyls and most lipid-related traits, in serum and plasma, were robust to the tested pre and post-storage conditions. Pre-storage conditions impacted concentrations of glycolysis metabolites, acetate, albumin and amino-acids by levels that could potentially bias research results (up to 1.4SD difference compared with reference). Post-storage conditions affected histidine, phenylalanine and LDL-particle-size, with differences up to 1.4SD.\n\nConclusionsMost metabolic traits are robust to the pre- and post-storage conditions tested here and that may commonly occur in large-scale cohorts. However, concentrations of glycolysis metabolites, and amino-acids may be compromised.\n\nKey messagesO_LIIn large scale epidemiological studies, blood processing delays, incubation at high temperature prior to long term storage, and NMR profiling delays after long term storage, may occur.\nC_LIO_LIConcentrations of fatty acids, beta-hydroxybutyrate, glycoprotein acetyls and most lipid-related traits are robust to variations in pre-storage temperature and duration of incubation (4{degrees}C or 21{degrees}C for up to 48h prior to centrifugation) and post-storage sample handling (24h delay in sample preparation or NMR profiling).\nC_LIO_LIGlycolytic metabolite concentrations are altered by pre-storage conditions and amino-acids, particularly histidine and phenylalanine, by both, pre and post-storage conditions.\nC_LI

epidemiology↗

Proof of concept for quantitative urine NMR metabolomics pipeline for large-scale epidemiology and genetics

BackgroundQuantitative molecular data from urine are rare in epidemiology and genetics. NMR spectroscopy could provide these data in high-throughput, and it has already been applied in epidemiological settings to analyse urine samples. However, quantitative protocols for large-scale applications are not available.\n\nMethodsWe describe in detail how to prepare urine samples and perform NMR experiments to obtain quantitative metabolic information. Semi-automated quantitative lineshape fitting analyses were set up for 43 metabolites and applied to data from various analytical test samples and from 1,004 individuals from a population-based epidemiological cohort. Novel analyses on how urine metabolites associate with quantitative serum NMR metabolomics data (61 metabolic measures; n=995) were performed. In addition, confirmatory genome-wide analyses of urine metabolites were conducted (n=578). The fully automated quantitative regression-based spectral analysis is demonstrated for creatinine and glucose (n= 4,548).\n\nResultsIntra-assay metabolite variations were mostly <5% indicating high robustness and accuracy of the urine NMR spectroscopy methodology per se. Intra-individual metabolite variations were large, ranging from 6% to 194%. However, population-based inter-individual metabolite variations were even larger (from 14% to 1655%), providing a sound base for epidemiological applications. Metabolic associations between urine and serum were found clearly weaker than those within serum and within urine, indicating that urinary metabolomics data provide independent metabolic information. Two previous genome-wide hits for formate and 2-hydroxyisobutyrate were replicated at genome-wide significance.\n\nConclusionsQuantitative urine metabolomics data suggest broad novelty for systems epidemiology. A roadmap for an open access methodology is provided.

epidemiology↗

Precise temporal regulation of alternative splicing during neural development

Alternative splicing (AS) is a crucial step of gene expression that must be tightly controlled, but the precise timing of dynamic splicing switches during neural development and the underlying regulatory mechanisms are poorly understood. Here we systematically analyzed the temporal regulation of AS in a large number of transcriptome profiles of developing mouse cortices, in vivo purified neuronal subtypes, and neurons differentiated in vitro. Our analysis revealed early- and late-switch exons in genes with distinct functions, and these switches accurately define neuronal maturation stages. Integrative modeling suggests that these switches are under direct and combinatorial regulation by distinct sets of neuronal RNA-binding proteins including Nova, Rbfox, Mbnl and Ptbp. Surprisingly, various neuronal subtypes in the sensory systems lack Nova and/or Rbfox expression. These neurons retain the \"immature\" splicing program in early-switch exons, affecting numerous synaptic genes. These results provide new insights into the organization and regulation of the neurodevelopmental transcriptome.

molecular biology↗