Activated carbon cloth as support for mesenchymal stem cell growth and differentiation to osteocytes Jesu´ s Lo´pez Pen˜ alver a , Jose-Luis Linares-Ferna´ ndez a , Virgı´nea de Araujo Farı´as a , Marı´a Victoria Lo´ pez-Ramo´n b , Mohamed Tassi a , Francisco Javier Oliver c , Carlos Moreno-Castilla d , Jose´ Mariano Ruiz de Almodo´var a,e, * a Centro de Investigacio´n Biome´dica, Universidad de Granada, 18100 Armilla, Granada, Spain b Departamento de Quı ´mica Inorga´nica y Orga´nica, Universidad de Jae´n, 23071 Jae´n, Spain c Instituto de Parasitologı ´a y Biomedicina Lo´pez-Neyra, CSIC 18100, Armilla, Granada, Spain d Departamento de Quı ´mica Inorga´nica, Universidad de Granada, 18071 Granada, Spain e Hospital San Cecilio, 18012 Granada, Spain ARTICLE INFO Article history: Received 10 June 2009 Accepted 10 August 2009 Available online xxxx ABSTRACT Activated carbon cloth was shown to be a good support for the growth and differentiation of mesenchymal stem cells (MSCs). By using this approach, we improved the cell culture procedure and reduced the laboratory time required to obtain a very large number of MSCs suitable for utilization or differentiation. Ó 2009 Elsevier Ltd. All rights reserved. Stem cells vary widely but have two characteristic proper- ties, regardless of the tissue from which they derive: they can produce other stem cells of the same type in an unlimited manner, and they can give rise to a specific cell lineage for tis- sue maintenance or repair [1]. Multipotential MSCs can origi- nate a limited group of cell types, including chondrocytes, osteocytes, adipocytes, myocytes, and neurons. MSCs have been isolated from different compartments of the umbilical cord, among other tissues [2]. MSCs transplanted under the appropriate conditions give rise to three germinal layers and substantially contribute to all or at least most tissues after their injection into blastocytes [3]. In cell therapy, MSCs are isolated from the same patient or from a healthy donor, and a sufficient amount is grown in the laboratory for a dosage of 1–5 · 10 6 cells per kg of patient weight [4]. However, conventional culture of MSCs requires weekly passage, reducing their pluripotency and proliferation capacity because of exposure to enzymes (e.g., trypsin) that degrade cell surface proteins [5–7]. Majd et al. [6] recently de- scribed a novel method for continuously increasing the cul- ture surface at relatively constant cell densities, which can generate the large number of autologous and multipotent MSCs needed for successful regenerative medicine. The use of activated carbon cloth (ACC), which presents a large surface area, may fulfill the space requirements and avoid weekly passaging. In addition, carbon-based materials are of interest because they are well accepted by the biological environment [8,9]. However, very little research has been re- ported on the interactions between stem cells and three- dimensional scaffolds [10]. Living cells are known to attach to the surface of activated carbon via adsorption [11], and this process can be explained by colloid and surface chemistry in terms of electrostatic and hydrophobic interactions. Electro- static interactions are highly dependent on the solution pH, which affects the carbon surface charge and the dissociation or protonation of organic functional groups of the outer cell membrane. The strength of hydrophobic interactions is posi- tively related to the hydrophobicity of the cells and the carbon 0008-6223/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.carbon.2009.08.016 * Corresponding author: Address: Centro de Investigacio´ n Biome´dica, Universidad de Granada, 18100 Armilla, Granada, Spain. Fax: +34 958 819132. E-mail address: jmrdar@ugr.es (J.M.R.de Almodo´ var). CARBON xxx (2009) xxx – xxx available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/carbon Please cite this article in press as: Pen˜alver JL et al. Activated carbon cloth as support for mesenchymal stem cell growth and differentiation to osteocytes. Carbon (2009), doi:10.1016/j.carbon.2009.08.016 ARTICLE IN PRESS