Gene-modified mesenchymal stem cells express functionally active nerve growth factor on an engineered poly lactic glycolic acid (PLGA) substrate

Tissue Eng Part A. 2008 May;14(5):681-90. doi: 10.1089/tea.2007.0260.

Abstract

Delivery of cellular and/or trophic factors to the site of injury may promote neural repair or regeneration and return of function after peripheral nerve or spinal cord injury. Engineered scaffolds provide a platform to deliver therapeutic cells and neurotrophic molecules. We have genetically engineered mesenchymal stem cells (MSCs) from the green rat (CZ-004 [SD TgN(act-EGFP)OsbCZ-004]) to express nerve growth factor (NGF) using an adenoviral vector. Cells maintained their stem cell phenotype as judged by expression of CD71 and CD172 markers, and absence of the hematopoietic marker CD45. Cells continued to express green fluorescent protein (GFP) on a long-term basis. Morphology, viability, and growth kinetics were maintained when cells were grown on a poly-lactic-co-glycolic acid (PLGA) polymer scaffold. Under appropriate growth conditions, they differentiated into chondrogenic, osteogenic, and adipogenic phenotypes, demonstrating that they retained their characteristics as MSCs. NGF was secreted from transduced MSCs at physiologically relevant levels ( approximately 25 ng/mL) measured by enzyme-linked immunoabsorbent assay (ELISA). Secreted NGF was functionally active in a neurite growth assay with PC12 cells. We conclude that MSCs are a good candidate for delivery of therapeutic factors into the injured nervous system. They are autologous, may be genetically modified to express neurotrophins, and are compatible with polymer surfaces that may be used as a potential delivery system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Biocompatible Materials
  • Female
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Lactic Acid
  • Male
  • Materials Testing
  • Mesenchymal Stem Cells / metabolism*
  • Nerve Growth Factor / genetics*
  • Nerve Growth Factor / metabolism*
  • Neurites / ultrastructure
  • Polyglycolic Acid
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Rats
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Tissue Engineering / methods*
  • Tissue Scaffolds*
  • Transduction, Genetic

Substances

  • Biocompatible Materials
  • Recombinant Proteins
  • Green Fluorescent Proteins
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polyglycolic Acid
  • Lactic Acid
  • Nerve Growth Factor