Optimized Transduction of Human Monocyte-Derived Dendritic Cells by Recombinant Adeno-Associated Virus Serotype 6

Hum Gene Ther. 2010 Dec;21(12):1675-86. doi: 10.1089/hum.2010.087.

Abstract

Dendritic cells are the key antigen-presenting cells involved in the initiation of the adaptive immune response. Recombinant adeno-associated viruses (rAAVs) can transduce dendritic cells and have gained attention as potential vaccines capable of stimulating T cell immunity. Here we show that rAAV2 pseudotyped with type 6 capsid (rAAV2/6) exhibits significantly higher tropism for human monocyte-derived dendritic cells (MoDCs) than other serotypes and variants. Transduction was abolished by a single lysine-to-alanine mutation within the AAV6 capsid previously shown to inhibit binding to heparin. However, unlike rAAV2, soluble heparin did not inhibit rAAV2/6 transduction of MoDCs. Further enhancement of MoDC transduction was observed after mutation of Tyr-731 in the capsid of AAV6 consistent with a report that tyrosine residues are phosphorylated, leading to ubiquitination of capsids during uptake. Pseudotyped rAAV2/6 vectors containing a Y731F mutation minimally altered the immunophenotype of MoDCs, which retained their immunostimulatory ability and were able to stimulate an antigen-specific CD8(+) T cell clone. These findings should assist in the development of rAAV2/6 as a vaccine vector.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Capsid Proteins / genetics
  • Cell Differentiation
  • Dendritic Cells / metabolism*
  • Dendritic Cells / virology
  • Dependovirus / genetics*
  • Green Fluorescent Proteins / biosynthesis*
  • Green Fluorescent Proteins / genetics
  • Humans
  • Immunophenotyping
  • Molecular Sequence Data
  • Monocytes / cytology*
  • Mutagenesis, Site-Directed
  • Mutation
  • Recombinant Proteins / biosynthesis*
  • Recombinant Proteins / genetics
  • Sequence Alignment
  • Serotyping
  • Transduction, Genetic*
  • Viral Load
  • Viral Tropism

Substances

  • Capsid Proteins
  • Recombinant Proteins
  • Green Fluorescent Proteins