Stem Cell and Regenerative Medicine

Biography

Biography: Lucie Bacakova

Abstract

Adult stem cells, i.e. stem cells derived from various tissues of the adult organism, are promising for cell therapy and tissue engineering. These cells overcome the ethical and legal issues associated with the use of human embryonic and fetal stem cells, and also enable the use of autologous stem cells for the implantation into patients. Human bone marrow mesenchyme stem cells (bmMSCs) have been widely used and even applied in numerous clinical trials, e.g. for treatment of critical limb ischemia during diabetes [1], lower limb long bone nonunion [2] or neurological diseases [3]. Recently, another promising source of mesenchyme stem cells emerged, namely adipose tissue. In comparison with the bmMSCs, the adipose tissue-derived stem cells (ASCs) are available in larger quantities and by less invasive approaches, such as liposuction. Although ASCs were discovered relatively recently, in 2002 [4], they have been relatively widely clinically applied in human patients, particularly for reconstructive, corrective, aesthetic and cosmetic purposes [4, 5]. In our studies, we attempted to differentiate human ASCs, isolated from lipoaspirates obtained by liposuction, towards osteoblasts (Ob) and vascular smooth muscle cells (VSMCs). For differentiation towards Ob, the ASCs were seeded on chitosan/glucan/hydroxyapatite and cultivated in an osteogenic medium supplemented with ascorbic acid, β-glycerophosphate and dexamethasone. In comparison with commercially available human bmMSCs, the ASCs produced similar amounts of type I collagen and Runx2, i.e. early markers of osteogenic differentiation, but lower levels of osteocalcin, a late marker of osteogenic differentiation [6]. For differentiation towards VSMCs, the ASCs were cultivated in a medium supplemented with transforming growth factor-ß1 and bone morphogenic protein-4. This medium induced the appearance of alpha-actin, calponin and myosin heavy chain, i.e. an early, intermediate and late marker of VSMC differentiation, respectively, in ASCs, and the amount and intensity of fluorescence of these markers were further enhanced by cultivation in a lab-made pressure-generating dynamic cell culture system. Thus, ASCs appears to be more suitable for vasular tissue engineering than for bone tissue engineering.