1. ¹Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA, USA
2. ²305 Stellar-Chance Laboratory, FM Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, USA

Correspondence: Dr O Igoucheva, Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, 233 South 10th street, BLSB Room 326, Philadelphia, PA 19107, USA. E-mail: Olga.Igoucheva@jefferson.edu

Received 4 October 2007; Revised 4 December 2007; Accepted 16 January 2008; Published online 13 March 2008.

Abstract

Synthetic oligodeoxynucleotides (ODNs) had been employed in gene modification and represent an alternative approach to 'cure' genetic disorders caused by mutations. To test the ability of ODN-mediated gene repair in bone marrow-derived mesenchymal stem cells (MSCs), we established MSCs cell lines with stably integrated mutant neomycin resistance and enhanced green fluorescent protein reporter genes. The established cultures showed morphologically homogenous population with phenotypic and functional features of mesenchymal progenitors. Transfection with gene-specific ODNs successfully repaired targeted cells resulting in the expression of functional proteins at relatively high frequency approaching 0.2% . Direct DNA sequencing confirmed that phenotype change resulted from the designated nucleotide correction at the target site. The position of the mismatch-forming nucleotide was shown to be important structural feature for ODN repair activity. The genetically corrected MSCs were healthy and maintained an undifferentiated state. Furthermore, the genetically modified MSCs were able to engraft into many tissues of unconditioned transgenic mice making them an attractive therapeutic tool in a wide range of clinical applications.