Biology subjects

Goncalves, B.

Publications and source records attributed to Goncalves, B..

7 recordsLinked to original sources

bioRxiv2026

Loss of PKN2 drives fibroblast reprogramming and extracellular matrix remodelling in pulmonary fibrosis

Introduction Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease characterised by aberrant fibroblast function, extracellular matrix (ECM) remodelling and defective tissue repair. Protein kinase N2 (PKN2) is associated with accelerated forced vital capacity decline in IPF, but its functional role in pulmonary fibrosis remains unknown. We hypothesised that PKN2 regulates fibroblast phenotype and tissue repair. Methods PKN2 expression was assessed in human lung tissue, induced sputum and primary airway and parenchymal fibroblasts from non-fibrotic controls and patients with interstitial lung disease (ILD). DNA methylation was profiled using the Illumina HumanMethylationEPIC array. PKN2 function was investigated by siRNA-mediated depletion in primary human lung fibroblasts using transcriptomic, proteomic and functional analyses. Tissue repair was assessed following pharmacological PKN inhibition in zebrafish. Results PKN2 expression was reduced in ILD lung tissue and primary airway and parenchymal fibroblasts and further suppressed by TGF-{beta}1. Differential methylation was identified across the PKN2 locus in both fibroblast populations. Integrated transcriptomic and proteomic profiling following PKN2 depletion revealed coordinated remodelling of ECM, cell adhesion, non-canonical WNT and VEGF pathways, including dysregulation of COL1A1, WNT, VEGF and MMP1. PKN2 loss increased VEGF and MMP-1 secretion and accelerated fibroblast wound closure. PKN inhibition altered epithelial organisation and collagen fibre alignment during zebrafish wound repair. Conclusion PKN2 loss drives fibroblast reprogramming and aberrant ECM remodelling, establishing PKN2 as an important regulator of pulmonary fibroblast homeostasis and tissue repair.

cell biology↗

bioRxiv2026

Hierarchical cross-linking of a bacterial spore coat Hub protein

Hub proteins are highly connected nodes in protein-protein interaction networks and are often intrinsically disordered proteins (IDPs) or contain intrinsically disordered regions. In Bacillus subtilis, the morphogenesis of the spore surface is orchestrated by a set of so-called morphogenetic proteins that guide the assembly of distinct layers. Formation of the inner coat is directed by SafAFL and its shorter isoform, C30. Both are expressed early in sporulation under the control of {sigma}E and localize at the interface between the developing inner coat and the underlying cortex peptidoglycan. From this site, they act as organizational hubs, recruiting client proteins essential for coat maturation. Among these is Tgl, a transglutaminase synthesized later in development following activation of {sigma}K after engulfment completion. We show that the C30 domain exhibits IDP-like features yet self-assembles into >1200 kDa complexes stabilized by disulfide bonds and that these bonds are required for subsequent proper Tgl-mediated "spotwelding" cross-linking. Small-angle X-ray scattering (SAXS) and photobleaching show that Tgl immobilizes but does not drastically alter these assemblies. These findings support a hierarchical, biphasic model for inner coat assembly: initial self-assembly and disulfide stabilization, followed by Tgl-mediated cross-linking and structural stabilization. According to this model, the forms of SafAFL/C30 that dominate the two stages recruit different client proteins in register with the course of morphogenesis.

microbiology↗

bioRxiv2025

A Workflow to Create Personalised Musculoskeletal Models Based on Magnetic Resonance Images

Musculoskeletal simulations typically rely on generic models that may not accurately represent individual anatomy. While personalisation based on medical images can improve model accuracy, current approaches often require time-consuming workflows to create these models. We present a semi-automatic workflow for creating personalised musculoskeletal models based on magnetic resonance imaging (MRI) that does not require bone segmentation. Our workflow uses 3D Slicer and Python scripts employing Thin-Plate Spline transformation to map 106 homologous landmarks from generic models onto participants anatomy. Generic-scaled and MRI-based models were created for eight healthy participants, and simulations were performed using the participants 3D motion capture data. MRI-based models were compared with generic-scaled models through principal component analysis, and joint kinematics and joint contact forces were analysed between both modelling approaches. Clear geometric differences existed between model types, with MRI-based models showing wider pelvises and different femur/tibia proportions. Unlike generic models, MRI-based male and female models displayed systematic differences. Despite anatomical discrepancies, joint kinematics were similar between models of the same individual, except for pelvis tilt. Muscle moment arms were generally aligned with published data from cadaver studies. MRI-based models consistently produced higher joint contact forces with greater inter-individual variation, particularly at knee joints, compared to generic-scaled models. The proposed workflow simplifies MRI-based model creation while revealing significant sensitivity of joint contact forces to individual morphology, highlighting the importance of personalisation for biomechanical analyses. Author SummaryQuestions about healthy or pathological movement patterns in humans--critical for injury prevention, rehabilitation, and sports performance--are often explored with the help of musculoskeletal modelling. This approach uses a priori defined generic models of the human musculoskeletal system to study joint moments, muscle activation patterns and joint contact forces. Typically, a generic model is scaled to match the participants dimensions linearly, which does not allow for an accurate representation of their bone and muscle morphology. We developed a semi-automatic workflow to creating magnetic resonance imaging-based personalisation that does not require bone segmentation but closely matches individual geometry with the help of a non-linear fitting function. By comparing magnetic resonance imaging-based and generic-scaled models in eight individuals, we show systematic bias inherent to one of the most popular musculoskeletal models and demonstrate the importance of model personalisation for healthy adults. Our personalisation pipeline is openly available and easy to set up, which will facilitate musculoskeletal modelling studies based on highly personalised models in clinical and research settings, potentially improving treatment planning and biomechanical assessments in the future.

biophysics↗

bioRxiv2025

DR5 CAR-T cells target solid tumors and suppress MDSCs with minimal toxicity

Chimeric antigen receptor (CAR) T cell therapies have poor efficacy in solid tumors due to limited target specificity and an immunosuppressive tumor microenvironment. We investigated death receptor 5 (DR5) as a CAR target based on its high expression in both solid tumors and myeloid- derived suppressor cells (MDSCs). We engineered agonistic DR5-specific CAR constructs and evaluated their activity in multiple models, demonstrating DR5-expression-dependent tumor killing, confirmed by knockout and overexpression experiments. DR5-targeting single-chain variable fragments retained their pro-apoptotic activity when expressed on non-effector cells or extracellular vesicles. Among multiple CAR designs, we identified a construct with optimized binding affinity that maintained T cell viability while preserving strong tumor and MDSC-killing potency. To assess safety and efficacy in an immunocompetent setting, we also developed a murine DR5-targeted CAR. In multiple xenograft and syngeneic mouse models, DR5 CAR-T cells reduced tumor growth, prolonged survival, and did not cause detectable toxicity. In patient- derived organoids and tissue slices, DR5 CAR-T cells infiltrated tumor tissues, reduced MDSCs, boosted CD8+ T cell activity, and inhibited tumor growth. These findings support DR5-targeted CAR-T therapy as a promising strategy for treating solid tumors, which combines direct tumor cytotoxicity with immune activation and minimizes off-target effects. TeaserDR5 CAR-T cells eliminate tumor cells and MDSCs and activate tumor-resident CD8+ T cells within the TME.

cancer biology↗

bioRxiv2025

External and Internal Load Profiles of Male and Female Participants during a Walking Football Practice

BACKGROUNDHigh levels of sedentary behavior among older adults highlight the importance of walking football (WF) in promoting physical activity for healthy aging. This study examines the external and internal load profiles of male and female participants during a WF tournament, addressing a gap in research on game demands and induced load. METHODSThe study involved 176 players aged 50+ participating in a 40-min, 5v5 WF tournament with unlimited substitutions. External load (total and categorized distances) was measured using Global Positioning System (GPS), while heart rate (HR) monitors assessed internal load, including absolute HR and intensity zones based on %HRmax. RESULTSThe proportion of male participants (n=123; 70.3%) was higher than females (n=52; 29.7%), p<.001. They were similar in age (61.6{+/-}8.6 and 60.8{+/-}6.9, respectively). Males covered a higher distance per minute than females, with sex showing a moderate effect (63.3{+/-}10.7 m/min vs. 54.7{+/-}15.8 m/min; p < .001; Cohens dunbiased = 0.69 [0.36; 1.03]), especially in fast walking (41.7{+/-}12.2 m/min vs. 32.6{+/-}16.7 m/min; p < .001; Cohens dunbiased = 0.66 [0.33; 1.00]). Males played more time than females (22:26{+/-}09:47 min:ss vs. 15:41{+/-}07:46 min:ss; p<.001), with moderate effect (Cohens dunbiased = 0.73 [0.40; 1.06]). However, no differences between sexes were identified in the internal load variables, such that the female average %HRmax was 80{+/-}11% and the male was 82{+/-}8% during the practice. CONCLUSIONSOverall, while males generally exhibit higher external loads in WF, both sexes experience similar internal load demands, highlighting WFs potential as a scalable, health-promoting intervention for aging populations.

physiology↗

bioRxiv2023

Trial-to-trial similarity and distinctness of muscle synergy activation coefficients increases during learning and with a higher level of movement proficiency

Muscle synergy analyses are used to increase our understanding of motor control. Spatially fixed synergy vectors coordinate multiple co-active muscles through activation commands, known as activation coefficients. To better understand motor learning, it is crucial to know how synergy recruitment varies during a learning task and different levels of movement proficiency. Within one session participants walked on a line, a beam, and learned to walk on a tightrope - tasks that represent different levels of proficiency. Muscle synergies were extracted over all conditions and the number of synergies was determined through the knee-point of the total variance accounted for (tVAF) curve. We found that the tVAF of one synergy decreased with task proficiency (line < beam < tightrope). Additionally, trial-to-trial similarity and distinctness of synergy activation coefficients increased with proficiency and after a learning process. We conclude that precise adjustment and refinement of synergy activation coefficients play a crucial role in motor learning.

neuroscience↗

bioRxiv2019

Effect of progesterone on Candida albicans biofilm formation under acidic conditions: a transcriptomic analysis

Vulvovaginal candidiasis (VVC) caused by Candida albicans is a common disease worldwide. A very important C. albicans virulence factor is its ability to form biofilms on epithelium and/or on intrauterine devices promoting VVC. It has been shown that VVC has a hormonal dependency and that progesterone affects virulence traits of C. albicans cells. To understand how the acidic environment (pH 4) and progesterone (either alone and in combination) modulate C. albicans response during formation of biofilm, a transcriptomic analysis was performed together with characterization of the biofilm properties. Compared to planktonic cells, acidic biofilm-cells exhibited major changes in their transcriptome, including modifications in the expression of 286 genes that were not previously associated with biofilm formation in C. albicans. The vast majority of the genes up-regulated in the acidic biofilm cells (including those uniquely identified here) are known targets of Sfl1, and the expression of this regulator impaired formation of the acidic biofilm. Under the acidic conditions used, progesterone treatment reduced C. albicans biofilm biomass, structural cohesion, matrix quantity and susceptibility to fluconazole. Transcriptomic analysis of progesterone-exposed biofilms led to the identification of 65 down-regulated genes including, among others, the regulator Tec1 and several of its target genes suggesting that the function of this transcription factor is inhibited by the presence of the hormone. Overall, the results of this study show that progesterone modulates C. albicans biofilm formation and genomic expression under acidic conditions, which may have implications for C. albicans pathogenicity in the vaginal environment.\n\nAuthor summaryVulvovaginal candidiasis (VVC) is an infection of the vaginal tract that affects millions of women every year. It is caused by fungi of the genus Candida, mainly Candida albicans. Several C. albicans virulence factors contribute to the establishment of this infection, including the ability to form biofilms on vaginal walls and intrauterine devices. Candida species belong to vaginal microflora, however under certain conditions they can cause infection. It has been shown that conditions that prompt VVC include those leading to high progesterone levels, as pregnancy. Here we show that progesterone impairs the ability of C. albicans cells to form biofilms but causes a potential protective stress response. Indeed, we reveal an increased fluconazole resistance of biofilm cells grown in the presence of the hormone. Additionally, our results suggest that biofilm cells have a specific response to acidic conditions, as those established in the vaginal environment. Deepening the knowledge on the modulation of C. albicans virulence by vaginal conditions is essential for a full understanding of the pathogenesis of this species in the vaginal tract and contribute to the disclosure of new targets to treat VVC.

microbiology↗