Gene-Corrected Fibroblast Therapy for Recessive Dystrophic Epidermolysis Bullosa using a Self-Inactivating COL7A1 Retroviral Vector

J Invest Dermatol. 2016 Jul;136(7):1346-1354. doi: 10.1016/j.jid.2016.02.811. Epub 2016 Mar 16.

Abstract

Patients with recessive dystrophic epidermolysis bullosa (RDEB) lack type VII collagen and therefore have severely impaired dermal-epidermal stability causing recurrent skin and mucosal blistering. There is currently no specific approved treatment for RDEB. We present preclinical data showing that intradermal injections of genetically corrected patient-derived RDEB fibroblasts using a Good Manufacturing Practices grade self-inactivating COL7A1 retroviral vector reverse the disease phenotype in a xenograft model in nude mice. We obtained 50% transduction efficiency in primary human RDEB fibroblasts with an average low copy number (range = 1-2) of integrated provirus. Transduced fibroblasts showed strong type VII collagen re-expression, improved adhesion properties, normal proliferative capabilities, and viability in vitro. We show that a single intradermal injection of 3 × 10(6) genetically corrected RDEB fibroblasts beneath RDEB skin equivalents grafted onto mice allows type VII collagen deposition, anchoring fibril formation at the dermal-epidermal junction, and improved dermal-epidermal adherence 2 months after treatment, supporting functional correction in vivo. Gene-corrected fibroblasts previously showed no tumorigenicity. These data show the efficacy and safety of gene-corrected fibroblast therapy using a self-inactivating vector that has now been good manufacturing grade-certified and pave the way for clinical translation to treat nonhealing wounds in RDEB patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion
  • Cell Proliferation
  • Collagen Type VII / genetics*
  • Collagen Type VII / metabolism
  • Epidermolysis Bullosa Dystrophica / genetics*
  • Epidermolysis Bullosa Dystrophica / therapy*
  • Fibroblasts / cytology
  • Fibroblasts / metabolism*
  • Genes, Recessive
  • Genetic Therapy*
  • Genetic Vectors
  • HEK293 Cells
  • Humans
  • Keratinocytes / cytology
  • Mice
  • Mice, Nude
  • Mutation
  • Neoplasm Transplantation
  • Recombinant Proteins / genetics
  • Retroviridae
  • Skin / metabolism
  • Temperature

Substances

  • COL7A1 protein, human
  • Collagen Type VII
  • Recombinant Proteins