ORIGINAL ARTICLE EX VIVO GENE THERAPY USING AUTOLOGOUS DERMAL FIBROBLASTS EXPRESSING hLMP3 FOR RAT MANDIBULAR BONE REGENERATION Claudio Parrilla, MD, PhD, 1 Wanda Lattanzi, MD, PhD, 2 Anna Rita Fetoni, MD, 1 Francesco Bussu, MD, 1 Enrico Pola, MD, PhD, 3 Gaetano Paludetti, MD 1 1 Department of Otolaryngology, School of Medicine, Catholic University of Sacred Heart, Rome, Italy. E-mail: claudioparrilla@yahoo.com 2 Department of Anatomy and Cell Biology, School of Medicine, Catholic University of Sacred Heart, Rome, Italy 3 Department of Orthopaedics, School of Medicine, Catholic University of Sacred Heart, Rome, Italy Accepted 30 April 2009 Published online 22 July 2009 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hed.21185 Abstract: Background. Implantation of autologous skin fibroblasts transduced ex vivo with a replication-defective adenoviral vector, carrying the LIM mineralization protein-3 (Ad-LMP-3), and adsorbed on a hydroxyapatite/collagen (HA/ COL) scaffold. Methods. Twenty-seven Wistar rats were used. A 5-  5- mm full-thickness defect was created in the exposed mandi- ble. All animals were randomized into 3 experimental groups: (1) autologous dermal fibroblasts transduced with Ad-LMP-3 and adsorbed on the HA/COL; (2) nontransduced dermal fibro- blasts adsorbed on the HA/COL scaffold; and (3) HA/COL scaffold without cells. Three-dimensional micro-CT (3DmicroCT or 3DlCT) and histological analysis were performed. Results. Efficient neoosteogenesis was observed in ani- mals treated with LMP-3–expressing cells (group 1) as soon as 4 weeks after surgery. Conversely, nonsignificant bone forma- tion was detected in control animals (groups 2 and 3) at all time points tested. Conclusion. These results suggest that the experimental approach based on transplantation of genetically modified au- tologous cells could provide an alternative treatment for cranio- maxillo-facial defects. Nonetheless, additional data from the study on larger bone defects must follow to foresee a clinical application in the near future. V V C 2009 Wiley Periodicals, Inc. Head Neck 32: 310–318, 2010 Keywords: osteogenesis; mandibular bone defect; ex vivo gene therapy; LMP-3; autologous dermal fibroblast The repair of congenital or acquired bone defects, such as traumas and demolitive surgery due to tumoral disease, has continued to receive increasing attention by the biomedical scientific research, thus entailing the development of sev- eral new technologies, with direct applications to the clinical setting. The therapeutic options clinically available are currently restricted to allografts, microvas- cular bone and osteomyocutaneous flaps taken from an autologous donor site, and bone distrac- tion for reconstructive purposes. 1–3 In particular, bone ‘‘free flaps’’ harvested from the fibula, scapula, iliac crest, or rib repre- sent the therapeutic gold standard because they Correspondence to: C. Parrilla V V C 2009 Wiley Periodicals, Inc. 310 Gene Therapy Mandibular Regeneration HEAD & NECK—DOI 10.1002/hed March 2010