Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell-matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type specific and as such, we could generate a spatially segregated co-culture system for hESCs and NIH/3T3 fibroblasts using patterned nanorough glass surfaces.
Despite recent advances in single-cell genomic, transcriptional, and mass-cytometric profiling, it remains a challenge to collect highly multiplexed measurements of secreted proteins from single cells for comprehensive analysis of functional states. Herein, we combine spatial and spectral encoding with polydimethylsiloxane (PDMS) microchambers for codetection of 42 immune effector proteins secreted from single cells, representing the highest multiplexing recorded to date for a single-cell secretion assay. Using this platform to profile differentiated macrophages stimulated with lipopolysaccharide (LPS), the ligand of Toll-like receptor 4 (TLR4), reveals previously unobserved deep functional heterogeneity and varying levels of pathogenic activation. Uniquely protein profiling on the same single cells before and after LPS stimulation identified a role for macrophage inhibitory factor (MIF) to potentiate the activation of LPS-induced cytokine production. Advanced clustering analysis identified functional subsets including quiescent, polyfunctional fully activated, partially activated populations with different cytokine profiles. This population architecture is conserved throughout the cell activation process and prevails as it is extended to other TLR ligands and to primary macrophages derived from a healthy donor. This work demonstrates that the phenotypically similar cell population still exhibits a large degree of intrinsic heterogeneity at the functional and cell behavior level. This technology enables fullspectrum dissection of immune functional states in response to pathogenic or environmental stimulation, and opens opportunities to quantify deep functional heterogeneity for more comprehensive and accurate immune monitoring.single-cell analysis | cytokine | immune effector function | cellular heterogeneity | Toll-like receptor activation E merging evidence indicates that cell-to-cell variability can give rise to phenotypic differences within a genetically identical cell population (1, 2). Nongenetic heterogeneity is also emerging as a potential barrier to effective therapeutic intervention (3, 4). Recent advances in single-cell molecular profiling are beginning to address these questions. Single-cell RNA sequencing revealed dynamic and bimodal gene expression (5). Single-cell multicolor flow cytometry (6) and mass cytometry (7) can quantify phenotypic diversity and differential drug response even across the hematopoietic continuum. Although a limited number of signaling proteins can be measured using intracellular staining, most of these technologies measure transcriptional or phenotypic marker expression in single cells. It remains an unmet need to directly measure cellular functional outcomes in a highly multiplexed manner and in single cells. In the immune system, the immune effector functions are largely mediated by a panel of effector proteins (e.g., cytokines and chemokines) secreted from single cells. Due to phenotypic plasticity and functional diversity, immune cells purified for a well-defined phenot...
We report on the development of a nanowire substrate-enabled laser scanning imaging cytometry for rare cell analysis in order to achieve quantitative, automated, and functional evaluation of circulating tumor cells. Immuno-functionalized nanowire arrays have been demonstrated as a superior material to capture rare cells from heterogeneous cell populations. The laser scanning cytometry method enables large-area, automated quantitation of captured cells and rapid evaluation of functional cellular parameters (e.g. size, shape and signaling protein) at the single-cell level. This integrated platform was first tested for capture and quantitation of human lung carcinoma cells from a mixture of tumor cells and leukocytes. We further applied it to the analysis of rare tumor cells spiked in fresh human whole blood (several cells per mL) that emulate metastatic cancer patient blood and demonstrated the potential of this technology for analyzing circulating tumor cells in the clinical settings. Using a high-content image analysis algorithm, cellular morphometric parameters and fluorescence intensities can be rapidly quantitated in an automated, unbiased, and standardized manner. Together, this approach enables informative characterization of captured cells in situ and potentially allows for sub-classification of circulating tumor cells, a key step towards the identification of true metastasis-initiating cells. Thus, this nano-enabled platform holds great potential for studying the biology of rare tumor cells and for differential diagnosis of cancer progression and metastasis.
Although extensive research has been conducted to investigate various factors related to organizational justice, few studies have examined the link between personality traits and organizational justice. Using a field sample, we explored the relationships between the five-factor model of personality and organizational justice. Results indicated that agreeableness and neuroticism were important correlates of organizational justice. Specifically, agreeableness was found to be positively related to all four organizational justice components proposed by Colquitt (2001). Neuroticism was found to be negatively related to procedural justice and informational justice. Theoretical and practical implications of the results are discussed.
A flexible graphene field-effect transistor (Gr-FET) biosensor for ultrasensitive and specific detection of miRNA without labeling and functionalization is reported. The flexible biosensor presents robust performance even after multiple cycles of bending to a cylinder with an 8 mm radius. A DNA probe is designed with partial segment complementary to target miRNA, and immobilized on the graphene surface though π−π stacking interaction. After capture of target miRNA, a Dirac point shift in Gr-FET is induced, which shows a linear relationship with the target miRNA concentration on a semi-log scale. The Gr-FET-based biosensor finishes miRNA detection in 20 min, and is able to achieve a miRNA detection limit as low as 10 fM without any functionalization and labeling. The interaction processes of DNA-graphene and DNA-miRNA are confirmed through surface-enhanced Raman scattering technology. The proposed biosensor will have prospective applications in wearable electronics for health monitoring and disease diagnosis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.