Joining S100 proteins and migration:for better or for worse, in sickness and in health

The vast diversity of S100 proteins has demonstrated a multitude of biological correlations with cell growth, cell differentiation and cell survival in numerous physiological and pathological conditions in all cells of the body. This review summarises some of the reported regulatory functions of S100 proteins (namely S100A1, S100A2, S100A4, S100A6, S100A7, S100A8/S100A9, S100A10, S100A11, S100A12, S100B and S100P) on cellular migration and invasion, established in both culture and animal model systems and the possible mechanisms that have been proposed to be responsible. These mechanisms involve intracellular events and components of the cytoskeletal organisation (actin/myosin filaments, intermediate filaments and microtubules) as well as extracellular signalling at different cell surface receptors (RAGE and integrins). Finally, we shall attempt to demonstrate how aberrant expression of the S100 proteins may lead to pathological events and human disorders and furthermore provide a rationale to possibly explain why the expression of some of the S100 proteins (mainly S100A4 and S100P) has led to conflicting results on motility, depending on the cells used. © 2013 Springer Basel

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Cell segmentation and classification via unsupervised shape ranking

As histology patterns vary depending on different tissue types, it is typically necessary to adapt and optimize segmentation algorithms to these tissue type-specific applications. Here we present an unsupervised method that utilizes cell shape cues to achieve this task-specific optimization by introducing a shape ranking function. The proposed algorithm is part of our Layers™ toolkit for image and data analysis for multiplexed immunohistopathology images. To the best of our knowledge, this is the first time that this type of methodology is proposed for segmentation and ranking in cell tissue samples. Our new cell ranking scheme takes into account both shape and scale information and provides information about the quality of the segmentation. First, we introduce cell-shape descriptor that can effectively discriminate the cell-type's morphology. Secondly, we formulate a hierarchical-segmentation as a dynamic optimization problem, where cells are subdivided if they improve a segmentation quality criteria. Third, we propose a numerically efficient algorithm to solve this dynamic optimization problem. Our approach is generic, since we don't assume any particular cell morphology and can be applied to different segmentation problems. We show results in segmenting and ranking thousands of cells from multiplexing images and we compare our method with well established segmentation techniques, obtaining very encouraging results. © 2013 IEEE

Cell segmentation and classification via unsupervised shape ranking

As histology patterns vary depending on different tissue types, it is typically necessary to adapt and optimize segmentation algorithms to these tissue type-specific applications. Here we present an unsupervised method that utilizes cell shape cues to achieve this task-specific optimization by introducing a shape ranking function. The proposed algorithm is part of our Layers™ toolkit for image and data analysis for multiplexed immunohistopathology images. To the best of our knowledge, this is the first time that this type of methodology is proposed for segmentation and ranking in cell tissue samples. Our new cell ranking scheme takes into account both shape and scale information and provides information about the quality of the segmentation. First, we introduce cell-shape descriptor that can effectively discriminate the cell-type's morphology. Secondly, we formulate a hierarchical-segmentation as a dynamic optimization problem, where cells are subdivided if they improve a segmentation quality criteria. Third, we propose a numerically efficient algorithm to solve this dynamic optimization problem. Our approach is generic, since we don't assume any particular cell morphology and can be applied to different segmentation problems. We show results in segmenting and ranking thousands of cells from multiplexing images and we compare our method with well established segmentation techniques, obtaining very encouraging results. © 2013 IEEE

Tissue segmentation and classification using graph-based unsupervised clustering

Automated segmentation and quantification of cellular and subcellular components in multiplexed images has allowed for a combination of both spatial and protein expression information to become available for analysis. However, performing analyses across multiple patients and tissue types continues to be a challenge, as well as the greater challenge of tissue classification itself. We propose a model of tissues as interconnected networks of epithelial cells whose connectivity is determined by their size, specific expression levels, and proximity to other cells. These Biomarker Enhanced Tissue Networks (BETN) reflect both the individual nature of the cells and the complex cell to cell relationships within the tissue. Performing a simple analysis of such tissue networks managed to successfully classify epithelial cells from stromal cells across multiple patients and tissue types. Further experiments show that significant information about the structure and nature of tissues can also be extracted through analysis of the networks, which will hopefully move towards the eventual goal of true tissue classification. © 2012 IEEE

System and method for multiplexed biomarker quantitation using single cell segmentation on sequentially stained tissue

Improved systems and methods for the analysis of digital images are provided. More particularly, the present disclosure provides for improved systems and methods for the analysis of digital images of biological tissue samples. Exemplary embodiments provide for: i) segmenting, ii) grouping, and iii) quantifying molecular protein profiles of individual cells in terms of Sub cellular compartments (nuclei, membrane, and cytoplasm). The systems and methods of the present disclosure advantageously perform tissue segmentation at the Sub-cellular level to facilitate analyzing, grouping and quantifying protein expression profiles of tissue in tissue sections globally and/or locally. Performing local-global tissue analysis and protein quantification advantageously enables correlation of spatial and molecular configuration of cells with molecular information of different types of cancer

System and method for multiplexed biomarker quantitation using single cell segmentation on sequentially stained tissue: US 8,995,740

Improved systems and methods for the analysis of digital images are provided. More particularly, the present disclosure provides for improved systems and methods for the analysis of digital images of biological tissue samples. Exemplary embodiments provide for: i) segmenting, ii) grouping, and iii) quantifying molecular protein profiles of individual cells in terms of Sub cellular compartments (nuclei, membrane, and cytoplasm). The systems and methods of the present disclosure advantageously perform tissue segmentation at the Sub-cellular level to facilitate analyzing, grouping and quantifying protein expression profiles of tissue in tissue sections globally and/or locally. Performing local-global tissue analysis and protein quantification advantageously enables correlation of spatial and molecular configuration of cells with molecular information of different types of cancer