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Bacterial cellulose (BC) membranes were modified with nitrogen plasma in order to enhance cell affinity. The surface properties of the untreated and plasma modified BC (BCP) were analyzed through contact angle measurements, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The effect of the plasma treatment on the adhesion of microvascular (HMEC-1), neuroblast (N1E-115) and fibroblast (3T3) cell lines was analyzed. The nitrogen plasma treatment did not increase the wettability of the material, but increased the porosity and surface chemistry, as noticed by the presence of nitrogen. XPS analysis revealed the stability of the modified material along time and autoclave sterilization. The cell adhesion and proliferation of HMEC-1 and N1E-115 cells was significantly improved in the BCP, in contrast with the 3T3 cells, revealing a cell-specific effect. This work highlights the potential of plasma treatment for the modification of the BC surface properties, enhancing its potential for biomedical applications. ; Programme Alβan, the European Union Programme of High Level Scholarships for Latin America. ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brasil. ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasil. ; Fundação para a Ciência e a Tecnologia (FCT) – POCTI, ...

A wide variety of biomaterials and bioactive molecules have been applied as scaffolds in neuronal tissue engineering. However, creating devices that enhance the regeneration of nervous system injuries is still a challenge, due the difficulty in providing an appropriate environment for cell growth and differentiation and active stimulation of nerve regeneration. In recent years, bacterial cellulose (BC) has emerged as a promising biomaterial for biomedical applications due its properties, such as high crystallinity, an ultrafine fiber network, high tensile strength and biocompatibility. The small signaling peptides found in the proteins of extracellular matrix are described in the literature as promoters of adhesion and proliferation for several cell lineages on different surfaces. In this work, the peptide IKVAV was fused to a carbohydrate-binding module (CBM3) and used to modify BC surfaces, with the goal of promoting neuronal and mesenchymal stem cell (MSC) adhesion. The recombinant proteins IKVAV-CBM3 and (19)IKVAV-CBM3 were successfully expressed in E. coli, purified through affinity chromatography and stably adsorbed to the BC membranes. The effect of these recombinant proteins, as well as RGD-CBM3, on cell adhesion was evaluated by MTS colorimetric assay. The results showed that the (19)IKVAV-CBM3 was able to significantly improve the adhesion of both neuronal and mesenchymal cells and had no effect on the other cell lineages tested. The MSC neurotrophin expression in cells grown on BC membranes modified with the recombinant proteins was also analyzed. ; Renata A. N. Pertile gratefully acknowledges support by the Programme Al beta an, the European Union Programme of High Level Scholarships for Latin America (Scholarship No. E07D401931BR). The author Susana Moreira is recipient of a SFRH/BPD/64726/2009 fellowship from Fundacao para a Ciencia e a Tecnologia (FCT, Portugal). Fabia K. Andrade is the recipient of a fellowship from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, ...