UBE2L3 regulates TLR7-induced B cell autoreactivity in Systemic Lupus Erythematosus.

Both TLR7 and NF-κB hyperactivity are known to contribute to pathogenesis in Systemic Lupus Erythematosus (SLE), driving a pro-interferon response, autoreactive B cell expansion and autoantibody production. UBE2L3 is an SLE susceptibility gene which drives plasmablast/plasma cell expansion in SLE, but its role in TLR7 signalling has not been elucidated. We aimed to investigate the role of UBE2L3 in TLR7-mediated NF-κB activation, and the effect of UBE2L3 inhibition by Dimethyl Fumarate (DMF) on SLE B cell differentiation in vitro. Our data demonstrate that UBE2L3 is critical for activation of NF-κB downstream of TLR7 stimulation, via interaction with LUBAC. DMF, which directly inhibits UBE2L3, significantly inhibited TLR7-induced NF-κB activation, differentiation of memory B cells and plasmablasts, and autoantibody secretion in SLE. DMF also downregulated interferon signature genes and plasma cell transcriptional programmes. These results demonstrate that UBE2L3 inhibition could potentially be used as a therapy in SLE through repurposing of DMF, thus preventing TLR7-driven autoreactive B cell maturation.

Patient and family perceptions of the provision of medicines as part of virtual outpatient consultations for children during COVID-19 pandemic.

OBJECTIVES: To evaluate (1) views and perceptions of patients/parents/carers and healthcare professionals on the medicines optimisation (MO) process following virtual outpatient clinic (VOC) during the COVID-19 pandemic and (2) the processes introduced at this time, identifying areas for improvements and suggest potential solutions. DESIGN: A mixed-methods service evaluation using qualitative and quantitative methods of the MO pathway in children aged 0-18 years following VOC across three specialist children's units.Semi-structured interviews were conducted over the telephone with the participants exploring their experiences and categorised into themes.Process mapping sessions with the multidisciplinary team identified areas for improvement and an ease impact framework developed for potential solutions.Outcome measures included: (1) themes from interviews, (2) patients satisfaction rates, (3) process maps and (4) development of a simplified future process. RESULTS: One hundred and twenty-five patients' families were contacted: 71 families consented to participate and their views were categorised into four main themes: (1) patient experience, (2) communication, (3) need for virtual video consultations for patient education by hospital pharmacists and (4) need for electronic processes to send prescriptions to local pharmacies.Median patient satisfaction rate was 96% (range 67%-100%). The convenience of receiving medications directly to patient's homes; access to medicines information helplines and education provided by pharmacists were regarded as valuable. Communication between care providers, development of virtual video consultations by hospital pharmacists and electronic transfer of some prescriptions directly to community pharmacies were identified as areas of improvement. CONCLUSIONS: Participants appreciated the pharmacy processes adopted during the pandemic, however, challenges and recommendations for improvement in delivering MO VOC were identified. As digital innovations evolve within the NHS, future research should focus on integrated care and improved communication between care providers with selected medications prescribed directly to community pharmacies using electronic prescription service, with clinical screening and education provided by hospital pharmacists.

Role of distinct fibroblast lineages and immune cells in dermal repair following UV radiation-induced tissue damage.

Solar ultraviolet radiation (UVR) is a major source of skin damage, resulting in inflammation, premature ageing, and cancer. While several UVR-induced changes, including extracellular matrix reorganisation and epidermal DNA damage, have been documented, the role of different fibroblast lineages and their communication with immune cells has not been explored. We show that acute and chronic UVR exposure led to selective loss of fibroblasts from the upper dermis in human and mouse skin. Lineage tracing and in vivo live imaging revealed that repair following acute UVR is predominantly mediated by papillary fibroblast proliferation and fibroblast reorganisation occurs with minimal migration. In contrast, chronic UVR exposure led to a permanent loss of papillary fibroblasts, with expansion of fibroblast membrane protrusions partially compensating for the reduction in cell number. Although UVR strongly activated Wnt signalling in skin, stimulation of fibroblast proliferation by epidermal ß-catenin stabilisation did not enhance papillary dermis repair. Acute UVR triggered an infiltrate of neutrophils and T cell subpopulations and increased pro-inflammatory prostaglandin signalling in skin. Depletion of CD4- and CD8-positive cells resulted in increased papillary fibroblast depletion, which correlated with an increase in DNA damage, pro-inflammatory prostaglandins, and reduction in fibroblast proliferation. Conversely, topical COX-2 inhibition prevented fibroblast depletion and neutrophil infiltration after UVR. We conclude that loss of papillary fibroblasts is primarily induced by a deregulated inflammatory response, with infiltrating T cells supporting fibroblast survival upon UVR-induced environmental stress.

Characterisation of tumour microenvironment remodelling following oncogene inhibition in preclinical studies with imaging mass cytometry.

Mouse models are critical in pre-clinical studies of cancer therapy, allowing dissection of mechanisms through chemical and genetic manipulations that are not feasible in the clinical setting. In studies of the tumour microenvironment (TME), multiplexed imaging methods can provide a rich source of information. However, the application of such technologies in mouse tissues is still in its infancy. Here we present a workflow for studying the TME using imaging mass cytometry with a panel of 27 antibodies on frozen mouse tissues. We optimise and validate image segmentation strategies and automate the process in a Nextflow-based pipeline (imcyto) that is scalable and portable, allowing for parallelised segmentation of large multi-image datasets. With these methods we interrogate the remodelling of the TME induced by a KRAS G12C inhibitor in an immune competent mouse orthotopic lung cancer model, highlighting the infiltration and activation of antigen presenting cells and effector cells.

Employing core regulatory circuits to define cell identity.

The interplay between extrinsic signaling and downstream gene networks controls the establishment of cell identity during development and its maintenance in adult life. Advances in next-generation sequencing and single-cell technologies have revealed additional layers of complexity in cell identity. Here, we review our current understanding of transcription factor (TF) networks as key determinants of cell identity. We discuss the concept of the core regulatory circuit as a set of TFs and interacting factors that together define the gene expression profile of the cell. We propose the core regulatory circuit as a comprehensive conceptual framework for defining cellular identity and discuss its connections to cell function in different contexts.

Magnetic Resonance Imaging of Part-solid Nodules: A Pilot Study.

PURPOSE: The aim of the study was to assess whether magnetic resonance imaging (MRI) characteristics can distinguish benign from malignant part-solid pulmonary nodules and predict the aggressiveness of the latter. We also sought to compare MRI-derived parameters with morphologic and physiological values derived from conventional examinations such as computed tomography and positron emission tomography/computed tomography. MATERIALS AND METHODS: This was an institutional review board-approved pilot study of 28 participants (23 women, mean age 73.5±13.8 y) with 32 biopsy-proven lesions. 3-T unenhanced pulmonary MRI examinations were performed with regions of interest drawn around lesions for T1, T2, T2*, and diffusion-weighted sequences. Apparent diffusion coefficient (ADC) and T2* values were calculated. Two weeks later the regions of interest were redrawn. MRI parameters were compared with lesion pathology, maximal standard uptake value (SUVmax), and Hounsfield units (HU). MRI lesion visibility was correlated with solid component size and the percentage of solid component. Intraobserver and interobserver agreements were determined. RESULTS: Only ADC values correlated with malignancy (P<0.05). ADC≥1.28 µm/ms predicted malignancy with 83.3% sensitivity (area under the curve 0.79). ADC and T2* correlated with adenocarcinoma subtypes (P<0.05). No MRI parameters predicted tumor differentiation (P>0.11). SUVmax did not correlate with any MRI parameters (P>0.56). Visibility on T1-weighted images correlated with the percentage of solid components (P<0.03). T1 and T2 values showed significant correlation with HU measurements of the entire nodule (P<0.001 and P<0.024, respectively) and HU measurements of solid components (P=0.031 and 0.008, respectively). CONCLUSIONS: 3 T MRI with quantitative ADC values demonstrated potential for discriminating benign part-solid pulmonary nodules from malignant lesions. ADC and T2* values correlated with adenocarcinoma subtypes. No MRI parameters correlated with SUVmax. T1 and T2 values showed significant correlation with HU measurements of the entire nodule and of the solid components.