ABSTRACT
Today within the medical and scientifi c community almost everyone, believes and has great hopes that stem cell therapy offers unprecedented treatment opportunities for developing new medical remedies for treating
Department of Cell Techniques and Applied Stem Cell Biology, Center for Biotechnology and Biomedicine (BBZ), University of Leipzig, Deutscher Platz 5, 04103 Leipzig, Germany. aE-mail:giri.shibashish@bbz.uni-leipzig.de *Corresponding author: augustinus.bader@bbz.uni-leipzig.de
patients with a myriad of diseases including extreme conditions such as blindness (Schwartz et al. 2012), heart problems (Ptaszek et al. 2012), kidney failure (Tan et al. 2012), liver failure (Takami et al. 2012), brain disorders (Lindvall and Kokaia 2005), to name just a few areas. The replacement of injured cells or aging cells using ex vivo expanded stem cells or differentiated functional cells has received great attention in the last decade. Despite much research and developments in the methodologies of stem cell expansion and differentiation, there is still a lack in the ability to produce a satisfactory number of appropriate stem cell derived functional and differentiated cells, that can meet clinical needs and necessities. Further, it is a clinical concern how the differentiated cells integrate into the injured part of tissue or organs upon transplantation. Two different microenvironment strategies can be used in vivo in stem cell therapy. First ex vivo microenvironment for specifi c lineage differentiation and the second one is the microenvironment of local injury where differentiated cells are expected to transplant. Although most research has been done using ex vivo stem cell differentiation, there is an extreme lack of evidence about how the differentiated functional cell behaves with the local microenvironment of the diseased/injured site upon transplantation. The second strategy is essential for further research work before application of stem cell therapeutics in a clinical setting. The relevance of the microenvironment for either strategy is highlighted and discussed here.
