Materials (Basel)
May 2018
In this study, a previously known high-affinity silica binding protein (SB) was genetically engineered to fuse with an integrin-binding peptide (RGD) to create a recombinant protein (SB-RGD). SB-RGD was successfully expressed in and purified using silica beads through a simple and fast centrifugation method. A further functionality assay showed that SB-RGD bound to the silica surface with an extremely high affinity that required 2 M MgCl₂ for elution.
View Article and Find Full Text PDFIn this study, we first synthesized a slow-degrading silica nanofiber (SNF2) through an electrospun solution with an optimized tetraethyl orthosilicate (TEOS) to polyvinyl pyrrolidone (PVP) ratio. Then, laminin-modified SNF2, namely SNF2-AP-S-L, was obtained through a series of chemical reactions to attach the extracellular matrix protein, laminin, to its surface. The SNF2-AP-S-L substrate was characterized by a combination of scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy, nitrogen adsorption/desorption isotherms, and contact angle measurements.
View Article and Find Full Text PDFA detailed genomic and epigenomic analyses of neural stem cells (NSCs) differentiation in synthetic microenvironments is essential for the advancement of regenerative medicine and therapeutic treatment of diseases. This study identified the changes in mRNA and miRNA expression profile during NSC differentiation on an artificial matrix. NSCs were grown on a surface-modified, electrospun tetraethyl-orthosilicate nanofiber (designated as SNF-AP) by providing a 3D-environment for cell growth and differentiation.
View Article and Find Full Text PDFIn this work, silica nanofibers (SNFs) were prepared by an electrospinning method and modified with poly-d-lysine (PDL) or (3-aminopropyl) trimethoxysilane (APTS) making biocompatible and degradable substrates for neuronal growth. The as-prepared SNF, modified SNF-PDL, and SNF-APTS were evaluated using scanning electron microscopy, nitrogen adsorption/desorption isotherms, contact angle measurements, and inductively coupled plasma atomic emission spectroscopy. Herein, the scanning electron microscopic images revealed that dissolution occurred in a corrosion-like manner by enlarging porous structures, which led to loss of structural integrity.
View Article and Find Full Text PDFIn this study, pure silica nanofibers (SNFs) were fabricated by the electrospinning technique. Subsequently, the as-prepared SNFs were modified with (3-aminopropyl) trimethoxysilane (APTS) for applications in neural tissue engineering. The structure and properties of the as-prepared SNFs and the modified SNFs (SNF-APxM, x = 1-3) were evaluated with FTIR, TGA, nitrogen adsorption/desorption isotherms, and SEM.
View Article and Find Full Text PDFBaculoviruses are one of the most studied insect viruses both in basic virology research and in biotechnology applications. Incorporating an internal ribosome entry site (IRES) into the baculovirus genome generates bi-cistronic baculoviruses expression vectors that produce two genes of interest. The bi-cistronic baculoviruses also facilitate recombinant virus isolation and titer determination when the green fluorescent protein was co-expressed.
View Article and Find Full Text PDFThe interaction between the synaptic adhesion molecules neuroligins and neurexins is essential for connecting the pre- and post-synaptic neurons, modulating neuronal signal transmission, and facilitating neuronal axogenesis. Here, we describe the simultaneous expression of the extracellular domain of rat neuroligin-1 (NL1) proteins along with the enhanced green fluorescent protein (EGFP) using the bi-cistronic baculovirus expression vector system (bi-BEVS). Recombinant rat NL1 protein, fused with signal sequence derived from human Azurocidin gene (AzSP), was secreted into the culture medium and the optimum harvest time for NL1 protein before the lysis of infected cells was determined through the release of cytosolic EGFP.
View Article and Find Full Text PDFA bi-cistronic baculovirus-insect/larval system containing a polyhedron promoter, an internal ribosome entry site (IRES), and an egfp gene was developed as a cost-effective platform for the production of recombinant human interferon gamma (rhIFN-γ). There was no significant difference between the amounts of rhIFN-γ produced in the baculovirus-infected Spodoptera frugiferda 21 cells grown in serum-free medium and the serum-supplemented medium, while the Trichoplusia ni (T. ni) and Spodoptera exigua (S.
View Article and Find Full Text PDFChikungunya virus infection has emerged in many countries over the past decade. There are no effective drugs for controlling the disease. To develop cell-based system for screening anti-virus drugs, a bi-cistronic baculovirus expression system was utilized to co-express viral structural proteins C (capsid), E2 and E1 and the enhanced green fluorescence protein (EGFP) in Spodoptera frugiperda insect cells (Sf21).
View Article and Find Full Text PDFRecombinant baculoviruses are suitable for the high-level production of large multi-protein complexes. A tri-cistronic expression vector was constructed by the inclusion of two internal ribosome entry sites (IRESs). In this novel polycistronic vector, one single polyhedrin promoter controlled the transcription of a tri-cistronic transcript.
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