Epigenetics of mesenchymal stem cells expanded by a bioreactor as compared to conventional manual culture

Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells capable of differentiating into multiple lineages of the mesenchyme and thought to play a role in tissue repair and immunomodulation Advances in tissue culture techniques have enabled the isolation and expansion of large quantities of MSCs for experimental use in regenerative medicine. Although studies so far using expanded human MSCs by conventional tissue culture have shown no malignant transformation, the potential of such complications is always a concern especially with the evolution of newer tissue culture techniques utilizing more potent growth factors and automation for large-scale production. In this study, we will compare the epigenetic characteristics of bioreactor-expanded MSCs versus plastic tissue culture flask techniques. Specifically we will analyze the functional, genetic and epigenetic sequels of culturing MSCs by relevant chromosomal karyotyping and SNP?microarrays. Subsequently, we will compare DNA?methylation profiles with the Infinium Human Methylation450 platform (Illumina, San Diego, USA). Identification of unique epigenetic patterns of cultured MSCs could alert to potential malignant transformation and serve as a tool for quality assurance in the rapidly expanding field of regenerative medicine.