Osteopontin as a Biomarker in Chronic Kidney Disease.

Osteopontin (OPN) is a ubiquitously expressed protein with a wide range of physiological functions, including roles in bone mineralization, immune regulation, and wound healing. OPN has been implicated in the pathogenesis of several forms of chronic kidney disease (CKD) where it promotes inflammation and fibrosis and regulates calcium and phosphate metabolism. OPN expression is increased in the kidneys, blood, and urine of patients with CKD, particularly in those with diabetic kidney disease and glomerulonephritis. The full-length OPN protein is cleaved by various proteases, including thrombin, matrix metalloproteinase (MMP)-3, MMP-7, cathepsin-D, and plasmin, producing N-terminal OPN (ntOPN), which may have more detrimental effects in CKD. Studies suggest that OPN may serve as a biomarker in CKD, and while more research is needed to fully evaluate and validate OPN and ntOPN as CKD biomarkers, the available evidence suggests that they are promising candidates for further investigation. Targeting OPN may be a potential treatment strategy. Several studies show that inhibition of OPN expression or activity can attenuate kidney injury and improve kidney function. In addition to its effects on kidney function, OPN has been linked to cardiovascular disease, which is a major cause of morbidity and mortality in patients with CKD.

Suspendable Hydrogel Nanovials for Massively Parallel Single-Cell Functional Analysis and Sorting.

Techniques to analyze and sort single cells based on functional outputs, such as secreted products, have the potential to transform our understanding of cellular biology as well as accelerate the development of next-generation cell and antibody therapies. However, secreted molecules rapidly diffuse away from cells, and analysis of these products requires specialized equipment and expertise to compartmentalize individual cells and capture their secretions. Herein, we describe methods to fabricate hydrogel-based chemically functionalized microcontainers, which we call nanovials, and demonstrate their use for sorting single viable cells based on their secreted products at high-throughput using only commonly accessible laboratory infrastructure. These nanovials act as solid supports that facilitate attachment of a variety of adherent and suspension cell types, partition uniform aqueous compartments, and capture secreted proteins. Solutions can be exchanged around nanovials to perform fluorescence immunoassays on secreted proteins. Using this platform and commercial flow sorters, we demonstrate high-throughput screening of stably and transiently transfected producer cells based on relative IgG production. Chinese hamster ovary cells sorted based on IgG production regrew and maintained a high secretion phenotype over at least a week, yielding >40% increase in bulk IgG production rates. We also sorted hybridomas and B lymphocytes based on antigen-specific antibody production. Hybridoma cells secreting an antihen egg lysozyme antibody were recovered from background cells, enriching a population of ∼4% prevalence to >90% following sorting. Leveraging the high-speed sorting capabilities of standard sorters, we sorted >1 million events in <1 h. IgG secreting mouse B cells were also sorted and enriched based on antigen-specific binding. Successful sorting of antibody-secreting B cells combined with the ability to perform single-cell RT-PCR to recover sequence information suggests the potential to perform antibody discovery workflows. The reported nanovials can be easily stored and distributed among researchers, democratizing access to high-throughput functional cell screening.

CAR-T design: Elements and their synergistic function.

Chimeric antigen receptor (CAR) T cells use re-engineered cell surface receptors to specifically bind to and lyse oncogenic cells. Two clinically approved CAR-T-cell therapies have significant clinical efficacy in treating CD19-positive B cell cancers. With widespread interest to deploy this immunotherapy to other cancers, there has been great research activity to design new CAR structures to increase the range of targeted cancers and anti-tumor efficacy. However, several obstacles must be addressed before CAR-T-cell therapies can be more widely deployed. These include limiting the frequency of lethal cytokine storms, enhancing T-cell persistence and signaling, and improving target antigen specificity. We provide a comprehensive review of recent research on CAR design and systematically evaluate design aspects of the four major modules of CAR structure: the ligand-binding, spacer, transmembrane, and cytoplasmic domains, elucidating design strategies and principles to guide future immunotherapeutic discovery.

Selective Promotion of Adhesion of Shewanella oneidensis on Mannose-Decorated Glycopolymer Surfaces.

Using glycopolymer surfaces, we have stimulated Shewanella oneidensis bacterial colonization and induced where the bacteria attach on a molecular pattern. When adherent bacteria were rinsed with methyl α-d-mannopyranoside, the glycopolymer-functionalized surfaces retained more cells than self-assembled monolayers terminated by a single mannose unit. These results suggest that the three-dimensional multivalency of the glycopolymers both promotes and retains bacterial attachment. When the methyl α-d-mannopyranoside competitor was codeposited with the cell culture, however, the mannose-based polymer was not significantly different from bare gold surfaces. The necessity for equilibration between methyl α-d-mannopyranoside and the cell culture to remove the enhancement suggests that the retention of cells on glycopolymer surfaces is kinetically controlled and is not a thermodynamic result of the cluster glycoside effect. The MshA lectin appears to facilitate the improved adhesion observed. Our findings that the surfaces studied here can induce stable initial attachment and influence the ratio of bacterial strains on the surface may be applied to harness useful microbial communities.

Development of a Three-Dimensional Bioengineering Technology to Generate Lung Tissue for Personalized Disease Modeling.

This unit describes a protocol for generation of lung organoids. A lung organoid is a 3D cell/hydrogel composite that resembles the morphology and cellular composition of the human distal lung. These tissue-engineered constructs provide an in vitro model of human lung and are best suited for disease modeling applications. The organoid generation methodology is flexible, allowing for easy scalability in the number of organoids produced and in the ability to accommodate a wide range of cell types. © 2018 by John Wiley & Sons, Inc.