1. Tropism-modified AAV Vectors Overcome Barriers to Successful Cutaneous Therapy
- Author
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Sallach, Jessica, Di Pasquale, Giovanni, Larcher, Fernando, Niehoff, Nadine, Rübsam, Matthias, Huber, Anke, Chiorini, Jay, Almarza, David, Eming, Sabine A, Ulus, Hikmet, Nishimura, Stephen, Hacker, Ulrich T, Hallek, Michael, Niessen, Carien M, and Büning, Hildegard
- Subjects
Medical Biotechnology ,Biomedical and Clinical Sciences ,Genetics ,Regenerative Medicine ,Biotechnology ,Gene Therapy ,Development of treatments and therapeutic interventions ,5.2 Cellular and gene therapies ,Capsid Proteins ,Dependovirus ,Genetic Engineering ,Genetic Therapy ,Genetic Vectors ,Humans ,Integrin alpha5 ,Keratinocytes ,Peptides ,Skin Abnormalities ,Transduction ,Genetic ,Tropism ,Biological Sciences ,Technology ,Medical and Health Sciences ,Clinical sciences ,Medical biotechnology - Abstract
Autologous human keratinocytes (HK) forming sheet grafts are approved as skin substitutes. Genetic engineering of HK represents a promising technique to improve engraftment and survival of transplants. Although efficacious in keratinocyte-directed gene transfer, retro-/lentiviral vectors may raise safety concerns when applied in regenerative medicine. We therefore optimized adeno-associated viral (AAV) vectors of the serotype 2, characterized by an excellent safety profile, but lacking natural tropism for HK, through capsid engineering. Peptides, selected by AAV peptide display, engaged novel receptors that increased cell entry efficiency by up to 2,500-fold. The novel targeting vectors transduced HK with high efficiency and a remarkable specificity even in mixed cultures of HK and feeder cells. Moreover, differentiated keratinocytes in organotypic airlifted three-dimensional cultures were transduced following topical vector application. By exploiting comparative gene analysis we further succeeded in identifying αvβ8 integrin as a target receptor thus solving a major challenge of directed evolution approaches and describing a promising candidate receptor for cutaneous gene therapy.
- Published
- 2014