Application of bioengineered human embryonic stem cells overexpressing FGF2 to study motoneuron survival in animal model of ventral root avulsion

Abstract

Neurodegeneration caused by both diseases and traumas is a reason for tremendous suffering and economical losses. Stem cells can promote neuronal survival and regeneration by two theoretically possible mechanisms: i) cell replacement and ii) delivering supportive factors. It is now thought that the positive effects of stem cell therapy at the present state are explained mostly by trophic support mechanisms, which modulate metabolic homeostasis in neurons. We however believe that with the progress of knowledge the cell replacement approaches will also be possible. For that, it is essential to understand the homeostasis of stem cells and the ways to alter their properties in a controllable fashion. In our host lab the stem cells have been already shown to support neuronal survival and regeneration. We now plan to study how stem cells can be "customized" for the particular purposes, and how they can be directed in a governable manner to accommodate them to the needs of neuroregeneration. Specifically, we propose to preserve affected motoneurons by employing supportive capacity of the human embryonic stem cells (hESC) specifically engineered to overexpress human fibroblast growth factor 2 (FGF2). The FGF2 is known as a factor promoting neuronal survival and outgrowth. We hypothesize that FGF2 is involved in modulation of cellular metabolic homeostasis. hESC is an established prototype cell source for future regenerative medicine. Moreover, hES cells are intensively used for developmental research, and e.g. for drug development. We have recently developed methods to bioengineer the hES cells in collaboration with Masaryk University in Brno, Czech Republic. Using these methods, we obtained hESC clones overexpressing human FGF2 in an inducible fashion. We have already imported the hESC clones to UNICAMP in accordance to the demanding internationally accepted ethical guidelines. We will apply our hESC clones in a 3D matrix developed and used in our host lab to support motoneuron survival in the rat model of ventral root avulsion (VRA). The motoneuron survival will be analyzed with immunohistochemical, morphological and molecular biology methods. The model with the inducible production of FGF2 by stem cells in-vivo will also provide a unique opportunity to study FGF2 related metabolic signaling. This 2-year Project is an initial part of the collaborative research framework aimed at developing advanced translational strategies for neuronal regeneration. (AU)