Biology subjects

Hanes, J.

Publications and source records attributed to Hanes, J..

6 recordsLinked to original sources

bioRxiv2026

Structure and epitope mapping of the conformational anti tau antibody DC11

Conformational antibody DC11 was previously shown to discriminate between physiological full length tau proteins and misfolded truncated tau proteins. It was also shown to catalyze in vitro tau aggregation, suggesting a connection with the pre-aggregation conformation of tau proteins. We have crystallized the Fab fragment of the DC11 antibody and characterized its binding with truncated tau proteins using ELISA, NMR and crosslinking mass spectrometry. The presumed model of the complex of DC11 antibody and truncated tau protein was obtained by docking tau321-391 conformations from coarse grained MD simulation into the antibody paratope.

biophysics↗

bioRxiv2025

Discovery and therapeutic exploitation of Master Regulatory miRNAs in Glioblastoma

Glioblastoma is a fatal primary malignant brain tumor, with an average survival of only 15 months despite surgical resection, chemotherapy, and radiation therapy. Due to the concurrent deregulation of numerous genes in glioblastoma, molecular monotherapies have not improved clinical outcomes. Evidence suggests that effectively targeting multiple deregulated molecules is essential for better therapies; however, this is limited by the lack of suitable drugs and the increased toxicity of combination therapies. To address this, we hypothesized that miRNAs, small gene-regulatory RNAs that suppress multiple target genes via sequence complementarity, could be developed to inhibit multiple deregulated genes simultaneously, leading to more effective treatments. We identified master regulatory miRNAs--those that target several deregulated genes in glioblastoma--using PAR-CLIP screenings in glioblastoma cells and analyzed TCGA tumor data to find which targets were deregulated. An algorithm ranked these targets based on their significance in glioblastoma malignancy. We selected two tumor suppressor master regulatory miRNAs, miR-340 and miR-382, and one oncogenic miRNA, miR-17. Validation showed that these miRNAs target critical glioblastoma pathways and significantly inhibit cell growth, survival, invasion, and tumor growth in vivo. We developed an innovative therapeutic delivery approach using Brain Penetrating Nanoparticles in combination with MRI-guided focused ultrasound and microbubbles, resulting in reduced tumor volume and extended survival in glioblastoma-bearing mice. This strategy offers a promising pathway for translating miRNA-based therapies into clinical trials for glioblastoma and other cancers. One Sentence SummaryWe developed and used new computational, experimental, and therapeutic approaches to identify and therapeutically deliver master regulatory miRNAs to inhibit the growth of glioblastoma, the most common and deadly primary brain tumor.

cancer biology↗

bioRxiv2023

Changes in lipid metabolism track with the progression of neurofibrillary pathology in tauopathies.

BackgroundAbnormal aggregation of tau protein that leads to brain inclusions is a common feature of neurodegenerative disorders called tauopathies. Recent evidence suggests the involvement of lipid metabolic deregulations in the pathogenesis of tauopathies. However, the role of tau protein in the regulation of lipid metabolism is much less characterized and not well understood. MethodsWe used a transgenic rat model for tauopathy to reveal metabolic alterations induced by neurofibrillary pathology. Transgenic rats express a tau fragment truncated at the N-and C-terminals. For phenotypic profiling, we performed targeted metabolomic and lipidomic analysis of brain tissue, CSF, and plasma, based on the LC-MS platform. To monitor disease progression, we employed samples from transgenic and control rats aged 4, 6, 8, 10, 12, and 14 months. To study neuron-glia interplay in lipidome changes induced by pathological tau we used well well-established multicomponent cell model system. Univariate and multivariate statistical approaches were used for data evaluation. ResultsWe showed that tau has an important role in the deregulation of lipid metabolism. In the lipidomic study, pathological tau was associated with higher production of lipids participating in protein fibrillization, membrane reorganization, and inflammation. Interestingly, significant changes have been found in the early stages of tauopathy before the formation of high-molecular-weight tau aggregates and neurofibrillary pathology. Increased secretion of pathological tau protein in vivo and in vitro induced upregulated production of phospholipids and sphingolipids and accumulation of lipid droplets in microglia. During the later stages of tauopathy, we found a connection between the transition of tau into an insoluble fraction and changes in brain metabolism. The results showed that dysregulation of lipid composition by pathological tau leads to disruption of the microenvironment and further propagation of pathology. ConclusionOur results revealed that lipid metabolism is significantly affected during different stages of tau pathology and provide new evidence that supports the contribution of pathological tau proteins in individual lipid pathways. Our data suggests that biologically active membrane lipids such as phospholipids and sphingolipids could represent new potential next-generation therapeutic targets in tauopathies.

neuroscience↗

bioRxiv2022

Analog of Kynurenic Acid Decreases Tau Pathology by Modulating Astrogliosis in Rat Model for Tauopathy.

Background and purposeKynurenines have immunomodulatory and neuroactive properties and can influence the central nervous system. Previous studies showed the involvement of the kynurenines in the pathogenesis and progression of neurodegenerative disease. In neurodegenerative disorders, including tauopathies, the tryptophan metabolism is shifted toward neurotoxic agents and the reduction of neuroprotectant products. Astrocyte-derived kynurenic acid serves as a neuroprotectant. However, systemic administration of kynurenic acid is not effective because of low permeability across the blood-brain barrier (BBB). Experimental ApproachWe used a kynurenic acid analog with similar biological activity but higher brain permeability to overcome BBB limitations. In the present study, we used amide derivate of kynurenic acid N-(2-N, N-dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamid (KYNA-1). We administered KYNA-1 for three months to tau transgenic rats SHR-24 and analyzed the effect on tau pathology and activation of glial cells. Primary glial cell cultures were applied to identify the mechanism of the KYNA-1 effect. Key resultsKYNA-1 was not toxic to rats after chronic three-month administration. When chronically administered, KYNA-1 reduced hyperphosphorylation of insoluble tau in the brain of transgenic rats. Noteworthily, the plasma total tau was also reduced. We determined that the effect of KYNA-1 on tau pathology was induced through the modulation of glial activation. KYNA-1 inhibited LPS induced activation of astrocytes and induced transformation of microglia to M2 phenotype. Conclusion and ImplicationsWe identified that the administration of KYNA-1 reduced tau hyperphosphorylation and neuroinflammation. KYNA-1 may serve as a promising treatment for tauopathies. What is already known?O_LIStudies showed tryptophan-kynurenine pathway changes in neurodegenerative disorders including tauopathies C_LIO_LIKynurenines exert immunomodulatory and neuroactive properties and have influence on the central nervous system C_LI What does this study add?O_LIChronic administration of synthetic analog of kynurenic acid (KYNA-1) reduces tau phosphorylation and astrogliosis in a transgenic rat model for tauopathies C_LIO_LIThe analog reversed LPS-induced inflammatory changes in glial cell cultures C_LI What is the clinical significance?O_LIAdministration of KYNA-1 analog shifted the tryptophan metabolism in the neuroprotectant direction C_LIO_LINeuroprotective analogs KYNA-1 can serve as a new and effective potential therapeutic approach for tauopathies C_LI

neuroscience↗

bioRxiv2021

Second Generation Antibodies Neutralize Emerging SARS-CoV-2 Variants of Concern

Recently emerged SARS-CoV-2 variants show resistance to some antibodies that were authorized for emergency use. We employed hybridoma technology combined with authentic virus assays to develop second-generation antibodies, which were specifically selected for their ability to neutralize new variants of SARS-CoV-2. AX290 and AX677, two monoclonal antibodies with non-overlapping epitopes, exhibit subnanomolar or nanomolar affinities to the receptor binding domain of the viral Spike protein carrying amino acid substitutions N501Y, N439K, E484K, K417N, and a combination N501Y/E484K/K417N found in the circulating virus variants. The antibodies showed excellent neutralization of an authentic SARS-CoV-2 virus representing strains circulating in Europe in spring 2020 and also the variants of concern B.1.1.7 and B.1.351. Finally, the combination of the two antibodies prevented the appearance of escape mutations of the authentic SARS-CoV-2 virus. The neutralizing properties were fully reproduced in chimeric mouse-human versions, which may represent a promising tool for COVID-19 therapy.

microbiology↗

bioRxiv2020

Large-scale Phenotypic Drug Screen Identifies Neuroprotectants in Zebrafish and Mouse Models of Retinitis Pigmentosa

Retinitis pigmentosa (RP) and associated inherited retinal diseases (IRDs) are caused by rod photoreceptor degeneration, necessitating therapeutics promoting rod photoreceptor survival. To address this, we tested compounds for neuroprotective effects in zebrafish and mouse RP models, reasoning drugs effective across species may translate better clinically. We first performed a large-scale phenotypic drug screen using a larval zebrafish model of inducible RP. 2,934 compounds, mostly human-approved drugs, were tested across six concentrations. Statistically, 113 compounds achieved "hit" status. Secondary tests of 42 high-priority hits confirmed eleven lead compounds. Nine leads were then evaluated in mouse RP models, with six exhibiting neuroprotective effects. An analysis of potential mechanisms of action suggested complementary activities. Paired lead compound assays in zebrafish showed additive neuroprotective effects for the majority. These results highlight the value of cross-species phenotypic drug discovery and suggest combinatorial drug therapies may provide enhanced therapeutic benefits for patients with RP and IRDs.

neuroscience↗