Control of Osteogenic Differentiation and Mineralization of Human Mesenchymal Stem Cells on Composite Nanofibers Containing Poly[lactic-co-(glycolic acid)] and Hydroxyapatite a Ji Hye Lee, b Nae Gyune Rim, b Hyun Suk Jung, Heungsoo Shin* Introduction Human mesenchymal stem cells (hMSCs) represent a prospective cell source for many tissue-engineering appli- cations, since they can be obtained from various origins such as bone marrow, umbilical blood, and adipose tissues. [1,2] Also hMSCs can be differentiated into meso- dermal lineages such as adipocytes, osteoblasts, and chondrocytes. [3–6] However, their unlimited proliferative potential and differentiation capability are only main- tained under a specific environment in which a complex orchestra of signals is tuned and regulated. As a result, hMSC-based tissue engineering strategies have spurred the development of ideal scaffolds that seek to provide Full Paper J. H. Lee, N. G. Rim, H. Shin Department of Bioengineering, College of Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Republic of Korea Fax: (þ82) 2 2298 2346; E-mail: hshin@hanyang.ac.kr H. S. Jung Department of Advanced Materials Engineering, Kookmin University, 861-1 Jeongneung-dong, Seongbuk-gu, Seoul 136-702, Republic of Korea a : Supporting information for this article is available at the bottom of the article’s abstract page, which can be accessed from the journal’s homepage at http://www.mbs-journal.de, or from the author. b These authors equally contributed to the current work. We fabricated composite fibrous scaffolds from blends of poly(lactide-co-glycolide) (PLGA) and nano-sized hydroxyapatite (HA) via electrospinning. SEM-EDX and AFM analysis demon- strated that HA was homogeneously dispersed in the nanofibers, and the roughness increased along with the amount of incorporated HA. When hMSCs were cultured on these PLGA/HA compo- site nanofibers, we found that incorporation of HA on the nanofibers did not affect cell viability whereas increased ALP activity and expression of osteogenic genes as well as the calcium mineral- ization of hMSCs. Our results indicate that the composite nanofibers can be offered as a potential bone regenerative biomaterial for stem cell based therapies. Macromol. Biosci. 2010, 10, 173–182 ß 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim DOI: 10.1002/mabi.200900169 173