CD14 is a ligand for the integrin α4β1

AbstractCell adhesion mediated by the integrin α4β1 plays a key role in many biological processes reflecting both the number and functional significance of α4β1 ligands. The lipopolysaccharide (LPS) receptor, CD14, is a GPI-linked cell surface glycoprotein with a wide range of reported functions and associations, some of which overlap with that of α4β1. This overlap led us to test the specific hypothesis that α4β1 and CD14 interact directly. Jurkat T cells (α4β1+) were found to adhere to a recombinant CD14-Fc protein via α4β1, whilst K562 cells (α4β1−) did not. However, stable reexpression of the α4-subunit conferred this ability. The adhesion of both cell types to CD14 displayed activation state-dependent binding very similar to the interaction of α4β1 with its prototypic ligand, VCAM-1. In solid-phase assays, CD14-Fc bound to affinity-purified α4β1 in a dose-dependent manner that was induced by activating anti-β1 mAbs. Finally, in related experiments, JY cells (α4β7+) were also found to attach to CD14-Fc in an α4-dependent manner. In summary, CD14 is a novel ligand for α4β1, exhibiting similar activation-state dependent binding characteristics as other α4β1 ligands. The biological relevance of this interaction will be the subject of further studies

First Report of Ventriculoperitoneal Shunt Infection due to Cyberlindnera fabianii.

Fungal infections in the central nervous system (CNS) are associated with significant morbidity and death. Transient fungemia in immunocompetent patients without any other risk factors for fungemia has been suggested as a possible mechanism that may lead to serious fungal ventriculoperitoneal (VP) shunt infections, but evidence is lacking. The clinical spectrum, diagnosis, and optimal therapy of Cyberlindnera fabianii infections remain to be determined. We describe the first case of CNS infection due to C. fabianii that occurred in an immunocompetent adult with a VP shunt. Spontaneous translocation with yeast that is not part of the normal gastrointestinal flora in the setting of ingestion of multiple servings of a fermentation product was the likely source from which Cyberlindnera fabianii gained entrance into the VP shunt system, causing meningitis in this patient. The authors conclude that, in view of the high morbidity associated with yeast infection of the CNS, long-term antifungal therapy should be strongly considered in cases where the VP shunt cannot be completely removed. Transient fungemia may lead to invasive disease in an immunocompetent host with VP shunt, even in the absence of any other risk factors for fungemia and even after remote placement of the VP shunt

Vinculin controls focal adhesion formation by direct interactions with talin and actin

Focal adhesions (FAs) regulate cell migration. Vinculin, with its many potential binding partners, can interconnect signals in FAs. Despite the well-characterized structure of vinculin, the molecular mechanisms underlying its action have remained unclear. Here, using vinculin mutants, we separate the vinculin head and tail regions into distinct functional domains. We show that the vinculin head regulates integrin dynamics and clustering and the tail regulates the link to the mechanotransduction force machinery. The expression of vinculin constructs with unmasked binding sites in the head and tail regions induces dramatic FA growth, which is mediated by their direct interaction with talin. This interaction leads to clustering of activated integrin and an increase in integrin residency time in FAs. Surprisingly, paxillin recruitment, induced by active vinculin constructs, occurs independently of its potential binding site in the vinculin tail. The vinculin tail, however, is responsible for the functional link of FAs to the actin cytoskeleton. We propose a new model that explains how vinculin orchestrates FAs

Modulation of FAK and Src adhesion signaling occurs independently of adhesion complex composition

Integrin adhesion complexes (IACs) form mechanochemical connections between the extracellular matrix and actin cytoskeleton and mediate phenotypic responses via posttranslational modifications. Here, we investigate the modularity and robustness of the IAC network to pharmacological perturbation of the key IAC signaling components focal adhesion kinase (FAK) and Src. FAK inhibition using AZ13256675 blocked FAK(Y397) phosphorylation but did not alter IAC composition, as reported by mass spectrometry. IAC composition was also insensitive to Src inhibition using AZD0530 alone or in combination with FAK inhibition. In contrast, kinase inhibition substantially reduced phosphorylation within IACs, cell migration and proliferation. Furthermore using fluorescence recovery after photobleaching, we found that FAK inhibition increased the exchange rate of a phosphotyrosine (pY) reporter (dSH2) at IACs. These data demonstrate that kinase-dependent signal propagation through IACs is independent of gross changes in IAC composition. Together, these findings demonstrate a general separation between the composition of IACs and their ability to relay pY-dependent signals

Basement membrane ligands initiate distinct signalling networks to direct cell shape

Cells have evolved mechanisms to sense the composition of their adhesive microenvironment. Although much is known about general mechanisms employed by adhesion receptors to relay signals between the extracellular environment and the cytoskeleton, the nuances of ligand-specific signalling remain undefined. Here, we investigated how glomerular podocytes, and four other basement membrane-associated cell types, respond morphologically to different basement membrane ligands. We defined the composition of the respective adhesion complexes using mass spectrometry-based proteomics. On type IV collagen, all epithelial cell types adopted a round morphology, with a single lamellipodium and large adhesion complexes rich in actin-binding proteins. On laminin (511 or 521), all cell types attached to a similar degree but were polygonal in shape with small adhesion complexes enriched in endocytic and microtubule-binding proteins. Consistent with their distinctive morphologies, cells on type IV collagen exhibited high Rac1 activity, while those on laminin had elevated PKCα. Perturbation of PKCα was able to interchange morphology consistent with a key role for this pathway in matrix ligand-specific signalling. Therefore, this study defines the switchable basement membrane adhesome and highlights two key signalling pathways within the systems that determine distinct cell morphologies. Proteomic data are availableviaProteomeXchange with identifier PXD017913

Global analysis reveals the complexity of the human glomerular extracellular matrix.

The glomerulus contains unique cellular and extracellular matrix (ECM) components, which are required for intact barrier function. Studies of the cellular components have helped to build understanding of glomerular disease; however, the full composition and regulation of glomerular ECM remains poorly understood. We used mass spectrometry-based proteomics of enriched ECM extracts for a global analysis of human glomerular ECM in vivo and identified a tissue-specific proteome of 144 structural and regulatory ECM proteins. This catalog includes all previously identified glomerular components plus many new and abundant components. Relative protein quantification showed a dominance of collagen IV, collagen I, and laminin isoforms in the glomerular ECM together with abundant collagen VI and TINAGL1. Protein network analysis enabled the creation of a glomerular ECM interactome, which revealed a core of highly connected structural components. More than one half of the glomerular ECM proteome was validated using colocalization studies and data from the Human Protein Atlas. This study yields the greatest number of ECM proteins relative to previous investigations of whole glomerular extracts, highlighting the importance of sample enrichment. It also shows that the composition of glomerular ECM is far more complex than previously appreciated and suggests that many more ECM components may contribute to glomerular development and disease processes. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the dataset identifier PXD000456

Engineering Assessment of the Miocene Aquifer System in Coastal Georgia

Proceedings of the 2001 Georgia Water Resources Conference, April 26 and 27, 2001, Athens, Georgia.Under contract to the Georgia Geologic Survey, Golder Associates Inc. (Golder) performed an investigation to characterize the water-bearing properties of the Miocene aquifer system in coastal Georgia (also referred to as the upper and lower Brunswick aquifers). The investigation focussed on specific areas where a cap has been imposed restricting further withdrawals from the Upper Floridan Aquifer. At selected sites in Bryan, Chatham, Effingham and Glynn counties, Golder installed pumping wells and observation wells within the Miocene aquifer(s) and performed 72-hour pumping tests. Results of the investigation revealed that the lower Brunswick aquifer is absent at the sites in Chatham, Effingham and Bryan counties. Furthermore, the upper Brunswick aquifer at these locations is poorly developed, producing sustainable yields of only five to 15 gpm. However, there are Miocene wells within the Brunswick aquifer in Bryan County that produce upwards of 100 gpm, indicating significant variation in the hydraulic properties of the Miocene aquifer system in this area. Both the upper and lower Brunswick aquifers are present at the Glynn County site. While the upper Brunswick aquifer at this location is capable of producing only about 10 gpm, the lower Brunswick aquifer can produce a sustainable yield of over 300 gpm. In addition to providing water resource information to planners, developers and industry, the data produced from this investigation will also be incorporated into regional groundwater flow and transport models being developed by the USGS for management of groundwater resources throughout coastal Georgia.Sponsored and Organized by: U.S. Geological Survey, Georgia Department of Natural Resources, Natural Resources Conservation Service, The University of Georgia, Georgia State University, Georgia Institute of TechnologyThis book was published by the Institute of Ecology, The University of Georgia, Athens, Georgia 30602-2202. The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of The University of Georgia, the U.S. Geological Survey, the Georgia Water Research Institute as authorized by the Water Resources Research Act of 1990 (P.L. 101-397) or the other conference sponsors

Using Free Text From Medical Notes To Enrich a Longitudinal Cohort Study

Introduction The Cleft Collective Cohort study is the world's largest multidisciplinary cleft lip/palate research programme. Despite being one of the most common birth anomalies, the causes of clefting are unknown. Treatment involves a considerable burden of care from birth onwards, together with a variety of social and psychological challenges. Objectives and Approach Our aim is to create the infrastructure and resources necessary to gain important new knowledge that will advance our understanding of the causes of cleft lip/palate, inform treatment and improve the lives of people born with cleft; data linkage is a key aspect of this. There are challenges associated with linking to multiple data sources (NHS Digital, Cleft National Registry). However, using the consent obtained, we are also able to link directly to the participant’s medical notes held by their NHS cleft team; enabling us to access a variety of data, including free text. Results The study already collects social and demographic data via questionnaires and genetic data from biological samples. Data linkage enriches this but also enables us to validate and address missing data problems. However, linkage to external sources brings many challenges, including, governance, costs, access issues. By gaining direct access to cleft team medical notes these issues are significantly reduced and provide us with rich phenotype data that cannot be obtained elsewhere, for example, via ‘read codes’ within electronic medical records. By tailoring our own data collection tool we can collect specific cleft data to enhance the resource and allow for subtype analyses. This process can be repeated throughout the duration of this longitudinal study for subsequent data. Conclusion/Implications Data linkage is a valuable resource but comes with many challenges. One route to overcome many of these issues is by accessing free text data directly from participants medical notes. The richness of these data allows for more in depth phenotypic analyses