Human mesenchymal stem cells (hMSCs) are multipotent progenitor cells with the ability to differentiate into several cell lineages, such as adipocytes, osteoblasts and chondrocytes. There is a great interest in application of hMSC in cell therapy and tissue engineering. Human MSCs are traditionally expanded in vitro using serum-supplemented culture medium. However, the presence of serum introduces variability in cell culture systems and is highly undesirable for clinical applications. Several serum-free media conditions for expansion of hMSCs were recently described in the literature. In these studies cell culture ware was coated with biological materials to enable hMSC adhesion in serum-free medium. The biological materials have limited shelf life, lot-to-lot variability and the potential for contamination with adventitious agents. To address the limitations of biological growth substrates, Corning Life Sciences, in collaboration with Geron Corporation, developed a novel, xeno-free, synthetic surface, the Corning® Synthemax™ Surface, for stem cell culture applications. This surface is comprised of an acrylate polymer functionalized with a short peptide sequence derived from the vitronectin protein, to mimic biological ligands for cell adhesion. Earlier data demonstrated successful long-term self-renewal of multiple hESC lines on Synthemax Surface in xeno-free media. This study illustrates the application of Synthemax Surface for long-term culture of bone marrow-derived hMSCs in serum-free MesenCult®-XF medium. Cell performance on the Synthemax Surface was compared to cells cultured a) on a biological coating recommended by the manufacturer of MesenCult®-XF medium; and b) in classical hMSC culture conditions on tissue culture treated (TCT) plastic in serum-containing medium. The results demonstrate efficient expansion of hMSCs on Synthemax Surface over the course of 9 serial passages (47 days) with average doubling time of 38 hrs and average 12-fold cell expansion in one passage. Throughout the multi-passage study on Synthemax Surface, cells maintained high viability, typical spindle-shaped morphology and phenotypic marker profile characteristic for multipotent hMSCs (high levels of CD166, CD44, negative for CD14, CD19). Similar cell performance was observed for cells cultured on the biological surface in serum-free medium. In contrast, cells cultured on TCT in 10% fetal bovine serum (FBS) exhibited much slower growth rate, with average doubling time of 189 hrs and average 3-fold expansion in one passage. After 6 passages, cell growth rate significantly decreased with concomitant decline in expression of phenotypic markers (CD166 and CD44), confirming replicative senescence of cells upon expansion in TCT/10% FBS condition. In summary, the results of this study suggest that Synthemax Surface, in combination with serum-free medium, provides a complete solution for long-term expansion of hMSCs under xeno-free, defined culture conditions. We anticipate that the Synthemax Surface will be valuable for both research purposes as well as therapeutic applications of hMSCs. Financial disclosure: This abstract was sponsored by Corning Incorporated.