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Kanso, H.

Publications and source records attributed to Kanso, H..

3 recordsLinked to original sources

Engineered Protein Nanosheets for the Scale up of Mesenchymal Stem Cell Culture on Bioemulsions

The rapid progress in cell therapies and stem cell technologies requires the development of novel bioprocessing and biomanufacturing pipelines able to cope with the scale up of cell manufacturing. In this respect, microdroplet technologies have already revolutionised the field of biotechnologies, but remain ill-suited to the culture of adherent cells. In this report, we describe the engineering of albumins with cell adhesive peptides for the stabilisation of microdroplets enabling the scale up of mesenchymal stem cell (MSC) expansion. We characterise the modified albumins prior to study their self-assembly at liquid-liquid interfaces via interfacial shear rheology, and mechanical strengthening through the formation of crosslinked nanosheets. The biofunctionalisation of these protein nanosheets is then characterised by fluorescence microscopy. In turn, the ability of the resulting bioactive microdroplets to promote rapid cell adhesion and expansion is examined and the extensive deposition of matrix associated with such cultures is characterised. The culture of MSCs is then scaled up 100 fold, first at the surface of fluorinated oil emulsions, then on plant-based emulsions stabilised by engineered protein nanosheets and the phenotype of resulting cells is characterised. The microdroplet culture system presented displays attractive advantages over existing technologies, in terms of simplicity of processing, compatibility with regulatory expectations and costs of production, and offers exciting opportunities for translation to cell manufacturing, for cell therapies and cultivated meat applications.

bioengineering↗

Assessing Inter-Individual Genetic Variability in PeachSugar Metabolism through Reliable Parameter Estimation of a Kinetic Model

Integrating genetic information into dynamical models is key to understand variations among genotypes and improve crop performances face to current agronomic and ecological constraints. A first and necessary step in building gene-to-phenotype models is the calibration of a large number of genotypes. We compared here two different strategies for the calibration of an Ordinary Differential Equations (ODE) kinetic model simulating the accumulation of different sugars during peach fruit development. First, the model was calibrated for each genotype independently using a Genotype-Based (GB) strategy. Two formulations of the problem have been tested, either as a Single-Objective Optimization (GBS) problem or as a Multi-Objective Optimization (GBM) problem. Second, the model was calibrated for all genotypes simultaneously using a Population-Based (PB) strategy. The two strategies were first applied to a set of simulated data and then to a real dataset derived from an interspecific population of 106 peach genotypes. Results showed that the GB strategy allowed for a high goodness of fit for most genotypes, especially in the GBS formulation. However, the estimated parameters suffered from a lack of practical identifiability as independent repetitions of the estimation algorithm did not always converge to the same value for most genotypes. The PB calibration strategy overcame this issue showing a good identifiability of the population parameter values, a goodness of fit comparable to the one obtained with the GB strategy and a good characterisation of parameter variations within the progeny, which is a key to assess the inter-individual genetic variability. These results are an important step towards the development of reliable gene-to-phenotype models.

plant biology↗

Supercharged Protein Nanosheets for Cell Expansion on Bioemulsions

Cell culture at liquid-liquid interfaces, for example at the surface of oil microdroplets, is an attractive strategy to scale up adherent cell manufacturing whilst replacing the use of microplastics. Such process requires the adhesion of cells at interfaces stabilized and reinforced by protein nanosheets displaying high elasticity, but also presenting cell adhesive ligands able to bind integrin receptors. In this report, supercharged albumins are found to form strong elastic protein nanosheets and mediate extracellular matrix (ECM) protein adsorption and cell adhesion. The interfacial mechanical properties and elasticity of supercharged nanosheets is characterized by interfacial rheology and behaviors are compared to those of native bovine serum albumin, human serum albumin and -lactalbumin. ECM protein adsorption to resulting supercharged nanosheets is then quantified via surface plasmon resonance and fluorescence microscopy, demonstrating the dual role supercharged albumins are proposed to play, as scaffold proteins structuring liquid-liquid interfaces and substrates for the capture of ECM molecules. Finally, the adhesion and proliferation of primary human epidermal stem cells is investigated, at pinned droplets, as well as on bioemulsions stabilized by corresponding supercharged nanosheets. This study demonstrates the potential of supercharged proteins for the engineering of biointerfaces for stem cell manufacturing, and draws structure-property relationships that will guide further engineering of associated systems.

bioengineering↗