Invited Speaker


Adult stem cell therapy for injured solid organ tissue
M. Korbling
USA

Adult hematopoietic tissue-derived stem cells are primarily used for hematopoietic reconstitution in patients with malignant lympho-hematopoietic malignancies undergoing stem cell transplantation. Their therapeutic use for solid organ tissue repair such as cardiac tissue is a novel treatment strategy (Korbling and Estrov, NEJM 2003). Besides hematopoietic stem cells (HSCs), mesenchymal stem cells and endothelial progenitor cells (EPCs) are known to contribute to solid-organ tissue repair. EPCs can be mobilized and collected in large quantities by apheresis (Korbling et al., Transfusion 2006). Cell delivery is by intra-arterial or intra-muscular (e.g., transendocardial) injection, or by co-transplantation with an injectable carrier (e.g., hydrogel). Alternatively, stem cells can be mobilized to be available at high concentration at the site of tissue repair.
Besides the involvement of stem cell differentiation/de- /trans-differentiation, tissue repair might also be mediated through cell fusion (Korbling, et al., Regenerative Medicine 2008) and/or paracrine secretion of transplanted cells (e.g., macrophages, monocytes).

The current concept of solid-organ tissue repair using hematopoietic tissue-derived cells/stem cells involves, as a first step, neovascularization at the borderzone near injured/infarcted tissue by transplantation of hematopoietic tissue-derived EPCs. This in turn is followed by activation of the solid organ tissue intrinsic stem cell pool with consecutive tissue repair.

Cardiac tissue repair in patients with acute MI and CNS tissue repair in stroke victims are currently at the forefront of cellular treatment strategies.