[Frontiers in Bioscience E4, 1813-1822, January 1, 2012]

Conversion of mouse fibroblasts to sphere cells induced by AlbuMAXI-containing medium

Pavan Rajanahalli1, Kyle Meyer1, Lin Zhu1, Brad D. Wagner2, Michael L. Robinson2, David A. King1, Yiling Hong1

1Department of Biology, and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio 45469, USA, 2Department of Zoology, Miami University, Oxford, Ohio 45056, USA

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Materials and methods
4. Results
4.1. AlbuMAX I -containing culture medium promoted the conversion of the fibroblast cells into sphere cells
4.2. Albumin-associated lipids arachidonic acid (AA) and pluronic F-68 were the critical components in AlbuMAX I that are responsible for the conversion effect
4.3. Characterization of the gene expression profile of sphere cells induced by AlbuMAX I-containing medium
4.4. The differentiation potential of the sphere cells
5. Discussion
6. Acknowlegements
7. Reference

1. ABSTRACT

The reprogramming of fibroblasts to pluripotent stem cells and the direct conversion of fibroblasts to functional neurons has been successfully manipulated by ectopic expression of defined factors. We demonstrate that mouse fibroblasts can be converted into sphere cells by detaching the fibroblast cells by protease and then using the AlbuMAX I-containing culture medium without genetic alteration. AlbuMAX I is a lipid-rich albumin. Albumin-associated lipids arachidonic acid (AA) and pluronic F-68 were responsible for this effect. The converted colonies were positive for both alkaline phosphatase and surface specific embryonic antigen-1 (SSEA-1) staining. Global gene expression analysis indicated that the sphere cells were in an intermediate state compared with mES cells and MEF cells. The sphere cells were able to differentiate into tissues representing all three embryonic germ layers following retinoic acid treatment, and differentiated into smooth muscle cells following treatment with vascular endothelial growth factor (VEGF). The study presented a potential novel approach to transdifferentiate mouse fibroblast cells into other cell lineages mediated by AlbuMAX I-containing culture medium.