Biology subjects

Esteves, M.

Publications and source records attributed to Esteves, M..

3 recordsLinked to original sources

bioRxiv2026

Preclinical translation of Neurofibromatosis type 1 (NF1) exon 17 skipping using targeted U7-SnRNA packaged into engineered AAV serotypes.

To facilitate the translation of NF1 exon 17 skipping as a mutation-specific therapy for Neurofibromatosis type 1 into in vivo testing, we have continued to develop more efficient antisense oligonucleotides (ASOs), humanized mouse models, and explored multiple delivery platforms including an adeno-associated virus (AAV)-U7-SnRNA vector approach. We evaluated both biodistribution and exon skipping efficacy of a U7-SnRNA targeting NF1 exon 17 with an SFFV-driven cassette containing T2A-linked Luciferase (Luc) and eGFP packaged in AAV-9, AAV-F and AAV-B1 capsids. We show that AAV-F is superior to AAV-9 and AAV-B1 for mouse brain delivery based on DNA transduction, GFP expression, and luciferase activity, but AAV-B1 delivers 2-4 fold more to sciatic nerve (SCN). In terms of exon skipping, AAV-F appears to induce the most skipping in liver and optic nerve (ON), while AAV-B1 mediates highest skipping in the liver, SCN, and ON. The identification of AAV serotypes that allow efficient transduction and delivery of transgenes to the mouse CNS and PNS is impactful for preclinical research in murine models of other diseases. Furthermore, this is both the first report of NF1 exon skipping efficacy in vivo and the first successful application of an U7-SnRNA for the restoration of functional neurofibromin for NF1. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/734312v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@34b7eborg.highwire.dtl.DTLVardef@116c11aorg.highwire.dtl.DTLVardef@dfb251org.highwire.dtl.DTLVardef@341cb5_HPS_FORMAT_FIGEXP M_FIG C_FIG

genetics↗

bioRxiv2025

Single cell-derived spheroids for real-time growth and metabolomic studies in breast cancer

Breast cancer remains a leading cause of cancer-related mortality, with disease progression and metastasis posing significant challenges in treatment. Three-dimensional (3D) cancer models have emerged as valuable tools for studying cancer cell biology in a physiologically relevant microenvironment. Studying the tumour heterogeneity and metabolic adaptations at the single-cell level can be crucial to identify factors driving metastatic progression. Here, we present a novel approach to generate single cell-derived breast cancer spheroids using cell lines (MCF-7 and MCF-10A) within a decellularised adipose tissue extracellular matrix (adECM). Spheroid culture conditions were optimised with integrated plasmonic nanosensors (gold nanostars - GNSs), to enable real-time surface-enhanced Raman scattering (SERS)-based measurements. Our results demonstrated that spheroid growth kinetics and viability in adECM were comparable to commonly used animal-derived matrices, validating its use as a reproducible ECM hydrogel. We further show that the concentration of plasmonic nanosensors used was compatible with cell culture and enabled SERS detection of a model reporter, paving the way for label-free, non-destructive analysis of cancer cell metabolism. This platform offers a promising approach to study cancer progression, including metabolic adaptations, with potential applications in biomarker discovery and preclinical research.

cancer biology↗

bioRxiv2018

MORPhA Scale: behavioral and electroencephalographic validation of a rodent anesthesia scale

Degree of anesthesia in laboratory rodents is normally evaluated by testing loss of reflexes. While these are useful endpoint assessments, they are of limited application to study induction/reversal kinetics or factors affecting individual susceptibility (e.g. sex or age). We developed and validated a grading system for a temporal follow up of anesthesia. The Minho Objective Rodent Phenotypical Anesthesia (MORPhA) scale was tested in mice and rats anaesthetized with a mixture of ketamine/dexmedetomidine (ket/dex - 3 doses). The scale comprises 12 behavioral readouts organized in 5 stages - (i) normal/(ii) hindered voluntary movement, elicited response to (iii) non-noxious/(iv) noxious stimuli and (v) absence of response - evaluated at regular time points. Progression across stages was monitored by electroencephalography (EEG) in rats during anesthesia induction and reversal (atipamezole) and during induction with a second anesthetic drug (pentobarbital). Higher anesthetic doses decreased the time to reach higher levels of anesthesia during progression, while increasing the time to regain waking behavior during reversal, in mice and in rats. A regular decrease in high frequencies (low and high gamma) power was observed as the MORPhA score increased during anesthesia induction, while the opposite pattern was observed during emergence from anesthesia through reversion of dex effect. The devised anesthetic scale is of simple application and provides a semi-quantifiable readout of anesthesia induction/reversal.

neuroscience↗