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The binding kinetics between cell surface receptors and extracellular biomolecules is critical to all intracellular and intercellular activity. Modeling and prediction of receptor-mediated cell functions are facilitated by measurement of the binding properties on whole cells, ideally indicating the subcellular locations or cytoskeletal associations that may affect the function of bound receptors. This dual need is particularly acute vis à vis ligand engineering and clinical applications of antibodies to neutralize pathological processes. Here, we map individual receptors and determine wholecell binding kinetics by means of functionalized force imaging, enabled by scanning probe microscopy and molecular force spectroscopy of intact cells with biomolecule-conjugated mechanical probes. We quantify the number, distribution, and association/ dissociation rate constants of vascular endothelial growth factor receptor-2 with respect to a monoclonal antibody on both living and fixed human microvascular endothelial cells. This general approach to direct receptor imaging simultaneously quantifies both the binding kinetics and the nonuniform distribution of these receptors with respect to the underlying cytoskeleton, providing spatiotemporal visualization of cell surface dynamics that regulate receptor-mediated behavior.cell surface ͉ mechanical imaging ͉ vascular endothelial growth factor receptor M olecular receptors at the living cell surface drive critical cell behaviors ranging from adhesion to differentiation, primarily by means of structural/functional changes induced by binding to extracellular molecules or ligands. Both the receptor location and the kinetics of ligand binding are important to the understanding of receptor-driven functions within cells, but few experimental approaches provide simultaneous access to spatial, temporal, and intermolecular force dynamics in individual, whole cells (1). Such quantification is crucial to understanding how cells within or among subpopulations may respond differentially to the same ligand [e.g., drug responsivity (2) and differentiation (3)] and how ligand binding can depend on clustering of multiple molecules [e.g., synapse formation (4)] or cytoskeletal association [e.g., focal adhesion formation (5)]. Several impressive experimental approaches including flow cytometry, immunocytochemical staining, Förster resonance energy transfer (FRET) and fluorescence recovery after photobleaching (FRAP) are based on optical signals that require either fluorophore-labeling or genetic modification of cell surface proteins (1). Binding affinity and kinetics among ligands and cell surface receptors are typically extracted from time course monitoring of total radio-or fluorophore-labeled ligand levels in the presence of unlabeled ligand counterparts, and thus the spatial distribution of active receptors during such competitive ligand binding is not accessed. Measurement of intermolecular interaction forces and associated binding kinetics of several antibody-antigen and ligand-receptor pai...

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SOVT is a rare entity. There are no guidelines, just recommendations for disease management. Based on our experience, broad-spectrum intravenous antibiotic, anticoagulation, and steroid therapy should be promptly introduced and if needed surgical intervention. SOVT can lead to devastating complications which include permanent loss of vision and in some cases a fatal outcome.

BackgroundGraves’ orbitopathy (GO) is subject to epidemiological and care-related changes. Aim of the survey was to identify trends in presentation of GO to the European Group On Graves’ Orbitopathy (EUGOGO) tertiary referral centres and initial management over time.MethodsProspective observational multicentre study. All new referrals with diagnosis of GO within September–December 2019 were included. Clinical and demographic characteristics, referral timelines and initial therapeutic decisions were recorded. Data were compared with a similar EUGOGO survey performed in 2012.ResultsBesides age (mean age: 50.5±13 years vs 47.7±14 years; p 0.007), demographic characteristics of 432 patients studied in 2019 were similar to those in 2012. In 2019, there was a decrease of severe cases (9.8% vs 14.9; p<0.001), but no significant change in proportion of active cases (41.3% vs 36.6%; p 0.217). After first diagnosis of GO, median referral time to an EUGOGO tertiary centre was shorter (2 (0–350) vs 6 (0–552) months; p<0.001) in 2019. At the time of first visit, more patients were already on antithyroid medications (80.2% vs 45.0%; p<0.001) or selenium (22.3% vs 3.0%; p<0.001). In 2019, the initial management plans for GO were similar to 2012, except for lid surgery (2.4% vs 13.9%; p<0.001) and prescription of selenium (28.5% vs 21.0%; p 0.027).ConclusionGO patients are referred to tertiary EUGOGO centres in a less severe stage of the disease than before. We speculate that this might be linked to a broader awareness of the disease and faster and adequate delivered treatment.