http://bura.brunel.ac.uk/handle/2438/32871 2026-05-19T19:24:49Z http://bura.brunel.ac.uk/handle/2438/33249 Title: Immune dysregulation in tuberculosis-diabetes comorbidity: mechanistic and translational insights Authors: Saula, AY; Cevik, M; Cliff, JM; Ronacher, K; Bowness, R Abstract: Background: Tuberculosis (TB) remains a leading cause of infectious disease mortality worldwide, and the rising prevalence of diabetes mellitus (DM) represents a major obstacle to TB control. DM increases susceptibility to TB, worsens disease severity, delays treatment response, and is associated with poorer outcomes, largely through disruption of host immunity. Methods: We conducted a systematic review of studies published between 1974 and May 31, 2023 that examined immunological mechanisms through which DM alters TB pathogenesis. In total, 81 eligible studies involving animal models, human participants, or combined approaches were identified and synthesised across different stages of TB. Results: Across studies, DM was associated with broad dysregulation of innate and adaptive immune responses, altered cytokine signalling, impaired granuloma structure and function, and reduced control of Mycobacterium tuberculosis (Mtb). Distinct immune profiles emerged between TB disease with DM and latent TB infection with DM, with heterogeneity partly explained by differences in study design, metabolic status, and disease stage. Importantly, emerging evidence indicates that pre-diabetes and intermediate hyperglycaemia may also compromise TB immunity and contribute to disease progression. Conclusion: Our findings highlight DM as a key immunometabolic modifier of TB pathogenesis. They also suggest that earlier metabolic optimisation and hostdirected therapeutic strategies could be explored as potential approaches to improve outcomes in this growing high-risk TB-DM population. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023431040. Description: Data availability statement: The data analyzed in this study is subject to the following licenses/restrictions: The datasets can be shared with researchers upon request. Requests to access these datasets should be directed to Aminat Y. Saula, ays27@bath.ac.uk.; Supplementary material: The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fimmu.2026.1803046/full#supplementary-material . 2026-04-23T00:00:00Z http://bura.brunel.ac.uk/handle/2438/33186 Title: Investigating replication fork blocks, replication-transcription conflicts and replication restart dynamics in Escherichia coli Authors: Peros, Stelinda Abstract: DNA replication is essential for genome stability, but it is constantly jeopardized by various obstacles such as nucleoprotein complexes and transcription–replication conflicts. If not properly resolved, these impediments lead to replication fork collapse, genomic instability, and even cell death. This thesis investigates how Escherichia coli preserves its replication integrity using three experimental systems: site-specific protein– DNA blockades, engineered replication–transcription conflicts, and chemical stress induced by saccharin exposure. These studies were supported by the development of an automated bioimage informatics pipeline, utilizing deep-learning segmentation to enable high-throughput quantitative analysis of cellular morphology and SOS-induced stress phenotypes in live-cell time-lapse microscopy. Using a novel inducible fork-block model, I demonstrate that the PriA–PriB– DnaT pathway is the primary restart mechanism at nucleoprotein obstacles, with PriA helicase activity being essential for efficient replication restart. Surprisingly, when large tandem repeats were placed on the opposite replichore, PriC rather than PriB played the dominant role, raising the possibility that restart pathway usage is influenced by obstacle size or chromosomal context. Replication–transcription conflicts, generated by introducing an ectopic origin of replication (oriZ), similarly required PriA helicase and PriB for efficient fork restart. In their absence, cells displayed severe filamentation, heterogeneous stress phenotypes, and elevated Cas1–Cas2 foci. To further define the nature of these collisions, I utilized an alternative origin (oriX); the comparison between head-on and co-directional orientations confirmed that cellular pathology was specifically conflict- dependent. Genetic suppression with an RNA polymerase–destabilizing mutation confirmed that these defects stem directly from transcriptional collisions rather than indirect effects. Finally, I show that saccharin, a widely used artificial sweetener, induces replication stress in E. coli, with PriB-deficient cells exhibiting pronounced defects and loss of viability. These findings highlight how dietary compounds may disrupt gut microbial physiology. Collectively, this work establishes PriA helicase as a central player in replication restart and a promising antibacterial target. Since stalled fork rescue is also critical in cancer cells, these results also provide conceptual bridges between bacterial DNA replication and oncogene-induced replication stress, opening avenues for both antimicrobial and cancer therapeutic development. Description: This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London 2025-01-01T00:00:00Z http://bura.brunel.ac.uk/handle/2438/33179 Title: CAR-mediated release of IL-10 increases the function of regulatory T cells: relevance for future clinical application Authors: Saleem, A; Peng, Q; Tang, Z; Mohseni, YR; Scottà, C; Shangaris, P; Smit, K; Vermeij, WP; Issa, F; Lombardi, G; Fruhwirth, GO Abstract: Regulatory T cell (Treg) therapy emerges for various indications associated with a breakdown of immune tolerance. Antigen-specific chimeric antigen receptor (CAR) Tregs are frontrunners for transplantation and autoimmune diseases and are currently being clinically evaluated. We aimed to link CAR-antigen engagement with immunosuppressive cargo release into the local microenvironment to boost efficacy and reduce side effects. We used our HLA-A∗02 CAR and immunosuppressive interleukin-10 (IL-10) as model components to generate human CAR Tregs that release IL-10 upon CAR engagement. These were compared to CAR Tregs with constitutive or no IL-10 expression by evaluating phenotypes, antigen-specific IL-10 release, and suppression of effector cell proliferation in vitro and performance in vivo in a humanized xenogeneic graft-versus-host disease (xeno-GvHD) model. We demonstrated successful multi-construct engineering of CAR Tregs, which released upon CAR engagement 2.5-fold more IL-10 than CAR Tregs lacking the corresponding antigen-specific IL-10 secretion module. Neither phenotype nor function was affected by expressing this module. In the xeno-GvHD model, we showed the beneficial effect of IL-10 release, particularly evident when compared to constitutive IL-10 expression that impaired CAR-Treg efficacy. We provide first proof-of-principle for engineering human CAR Tregs to release an immunosuppressive cytokine upon CAR engagement. This approach will both enhance the potency of CAR Tregs at the intended target sites and limit their off-target effects. Description: Data and code availability: The data presented here are available on request from the corresponding authors.; Supplemental information is available online at: https://www.sciencedirect.com/science/article/pii/S1525001626000870#appsec2 . 2026-02-06T00:00:00Z http://bura.brunel.ac.uk/handle/2438/33171 Title: Clinical assessment meets laboratory science: adapting OSCE methodology for authentic biosciences evaluation in the age of generative AI Authors: Mann, R; Tosi, S; Tree, D Abstract: The proliferation of generative artificial intelligence (AI) tools has fundamentally challenged traditional written assessments across higher education, with particular implications for laboratory-based disciplines where written work may substitute for demonstration of practical competence, necessitating approaches that prioritise direct performance. This study presents the adaptation of objective structured clinical examination (OSCE) methodology from medical education to laboratory biosciences, demonstrating a practical framework for authentic assessment in the AI era. We describe and evaluate the transformation of a microscopy assessment in FHEQ Level 4 Biomedical Sciences from a traditional laboratory report to a 20-minute OSCE-style practical evaluation. The redesigned assessment maintained grade distributions while eliminating AI vulnerability through real-time performance demonstration and conversational examination. The implementation achieved close alignment between learning outcomes and assessment methods while providing inherent resistance to generative AI exploitation through direct performance requirements. Equity implications are complex and context-dependent, with potential barriers for students with communication differences alongside potential benefits for others, such as those with written communication difficulties, emphasising the importance of balanced assessment portfolios and appropriate reasonable adjustments. The cross-disciplinary adaptation demonstrates that OSCE methodology offers a scalable solution to AI-era assessment challenges, with performance-focused design maintaining academic integrity more effectively than restrictive policies while enhancing authenticity and equity outcomes. Description: Perspective. 2026-03-24T00:00:00Z