Smart Sensor Control and Monitoring of an Automated Cell Expansion Process.

Immune therapy for cancer patients is a new and promising area that in the future may complement traditional chemotherapy. The cell expansion phase is a critical part of the process chain to produce a large number of high-quality, genetically modified immune cells from an initial sample from the patient. Smart sensors augment the ability of the control and monitoring system of the process to react in real-time to key control parameter variations, adapt to different patient profiles, and optimize the process.

Evaluation of Neurosecretome from Mesenchymal Stem Cells Encapsulated in Silk Fibroin Hydrogels.

Physical and cognitive disabilities are hallmarks of a variety of neurological diseases. Stem cell-based therapies are promising solutions to neuroprotect and repair the injured brain and overcome the limited capacity of the central nervous system to recover from damage. It is widely accepted that most benefits of different exogenously transplanted stem cells rely on the secretion of different factors and biomolecules that modulate inflammation, cell death and repair processes in the damaged host tissue.

Safety and tolerability of silk fibroin hydrogels implanted into the mouse brain.

Unlabelled: At present, effective therapies to repair the central nervous system do not exist. Biomaterials might represent a new frontier for the development of neurorestorative therapies after brain injury and degeneration. In this study, an in situ gelling silk fibroin hydrogel was developed via the sonication-induced gelation of regenerated silk fibroin solutions.

Mechanical behaviour and formation process of silkworm silk gut.

High performance silk fibers were produced directly from the silk glands of silkworms (Bombyx mori) following an alternative route to natural spinning. This route is based on a traditional procedure that consists of soaking the silk glands in a vinegar solution and stretching them by hand leading to the so called silkworm guts. Here we present, to the authors' best knowledge, the first comprehensive study on the formation, properties and microstructure of silkworm gut fibers.

Unexpected behavior of irradiated spider silk links conformational freedom to mechanical performance.

Silk fibers from Argiope trifasciata and Nephila inaurata orb-web weaving spiders were UV irradiated to modify the molecular weight of the constituent proteins. Fibers were characterized either as forcibly silked or after being subjected to maximum supercontraction. The effect of irradiation on supercontraction was also studied, both in terms of the percentage of supercontraction and the tensile properties exhibited by irradiated and subsequently supercontracted fibers.

Topographical and mechanical characterization of living eukaryotic cells on opaque substrates: development of a general procedure and its application to the study of non-adherent lymphocytes.

The mechanical behavior of living murine T-lymphocytes was assessed by atomic force microscopy (AFM). A robust experimental procedure was developed to overcome some features of lymphocytes, in particular their spherical shape and non-adherent character. The procedure included the immobilization of the lymphocytes on amine-functionalized substrates, the use of hydrodynamic effects on the deflection of the AFM cantilever to monitor the approaching, and the use of the jumping mode for obtaining the images.

Spider silk gut: development and characterization of a novel strong spider silk fiber.

Spider silk fibers were produced through an alternative processing route that differs widely from natural spinning. The process follows a procedure traditionally used to obtain fibers directly from the glands of silkworms and requires exposure to an acid environment and subsequent stretching. The microstructure and mechanical behavior of the so-called spider silk gut fibers can be tailored to concur with those observed in naturally spun spider silk, except for effects related with the much larger cross-sectional area of the former.

Chondrogenic potential of human dermal fibroblasts in a contractile, soft, self-assembling, peptide hydrogel.

The present paper describes a simple approach to obtain three-dimensional (3D) cartilage constructs using human normal dermal fibroblasts (hNDFs) cultured in a self-assembling peptide nanofibre scaffold. During the first days of culture, the 3D constructs underwent morphological changes consisting of a substantial contraction process that ended in a small compact structure. During this process the system became sensitive to induction with standard chondrogenic medium, evidenced by the expression of specific markers of mature cartilage.

Development of a three-dimensional bone-like construct in a soft self-assembling peptide matrix.

This work describes the development of a three-dimensional (3D) model of osteogenesis using mouse preosteoblastic MC3T3-E1 cells and a soft synthetic matrix made out of self-assembling peptide nanofibers. By adjusting the matrix stiffness to very low values (around 120 Pa), cells were found to migrate within the matrix, interact forming a cell-cell network, and create a contracted and stiffer structure. Interestingly, during this process, cells spontaneously upregulate the expression of bone-related proteins such as collagen type I, bone sialoprotein, and osteocalcin, indicating that the 3D environment enhances their osteogenic potential.

Nanometric self-assembling peptide layers maintain adult hepatocyte phenotype in sandwich cultures.

Background: Isolated hepatocytes removed from their microenvironment soon lose their hepatospecific functions when cultured. Normally hepatocytes are commonly maintained under limited culture medium supply as well as scaffold thickness. Thus, the cells are forced into metabolic stress that degenerate liver specific functions.

Differentiation of mouse embryonic stem cells in self-assembling peptide scaffolds.

Here, we describe the capacity of mouse embryonic stem cells (mESCs) to differentiate into osteoblast-like cells in a three-dimensional (3D) self-assembling peptide scaffold, a synthetic nanofiber biomaterial with future applications in regenerative medicine. We have previously demonstrated that classical tissue cultures (two-dimensional) as well as 3D-systems promoted differentiation of mESCs into cells with an osteoblast-like phenotype expressing osteopontin (OPN) and collagen type I (Col I), as well as high alkaline phosphatase (Alk Phos) activity and calcium phosphate mineralization. Interestingly, in 3D self-assembling peptide scaffold cultures, the frequency of appearance of embryonic stem-cell-like colonies was substantially enhanced, suggesting that this particular 3D microenvironment promoted the generation of a stem-cell-like niche that allows the maintenance of a small pool of undifferentiated cells.

FUNCTIONALIZED, SWELLABLE HYDROGEL LAYERS AS A PLATFORM FOR CELL STUDIES.

This paper reports the design, synthesis and characterization of thin films as a platform for studying the separate influences of physical and chemical cues of a matrix on the adhesion, growth and final phenotype of cells. Independent control of the physical and chemical properties of functionalized, swellable hydrogel thin films was achieved using initiated Chemical Vapor Deposition (iCVD). The systematic variation in crosslink density is demonstrated to control the swelling ability of the iCVD hydrogel films based on 2-hydroxyethyl methacrylate (HEMA).