Incorporation of porcine adenovirus 4 fiber protein enhances infectivity of adenovirus vector on dendritic cells: implications for immune-mediated cancer therapy

PLoS One. 2015 May 1;10(5):e0125851. doi: 10.1371/journal.pone.0125851. eCollection 2015.

Abstract

One strategy in cancer immunotherapy is to capitalize on the key immunoregulatory and antigen presenting capabilities of dendritic cells (DCs). This approach is dependent on efficient delivery of tumor specific antigens to DCs, which subsequently induce an anti-tumor T-cell mediated immune response. Human adenovirus serotype 5 (HAdV5) has been used in human studies for gene delivery, but has limited infection in DCs, which lack the proper receptors. Addition of the porcine fiber knob (PK) from porcine adenovirus type 4 to HAdV5 allows the virus to deliver genetic material via binding to glycosylated surface proteins and bypasses the coxsackie-and-adenovirus receptor required by wild-type HAdV5. In this study we explored the potential therapeutic applications of an adenovirus with PK-based tropism against cancers expressing mesothelin. Infectivity and gene transfer assays were used to compare Ad5-PK to wild-type HAdV5. Mouse models were used to demonstrate peptide specificity and T-cell responses. We show that the PK modification highly augmented infection of DCs, including the CD141+ DC subset, a key subset for activation of naïve CD8+ T-cells. We also show that Ad5-PK increases DC infectivity and tumor specific antigen expression. Finally, vaccination of mice with the Ad5-PK vector resulted in enhanced T-cell-mediated interferon gamma (IFN-γ) release in response to both mesothelin peptide and a tumor line expressing mesothelin. Ad5-PK is a promising tool for cancer immunotherapy as it improves infectivity, gene transfer, protein expression, and subsequent T-cell activation in DCs compared to wild-type HAdV5 viruses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviruses, Human
  • Adenoviruses, Porcine / genetics
  • Adenoviruses, Porcine / immunology
  • Animals
  • Capsid Proteins / genetics
  • Capsid Proteins / immunology
  • Capsid Proteins / therapeutic use*
  • Dendritic Cells / immunology
  • GPI-Linked Proteins / biosynthesis
  • Gene Transfer Techniques
  • Genetic Therapy*
  • Genetic Vectors
  • Humans
  • Immunotherapy*
  • Mesothelin
  • Mice
  • Neoplasms / genetics
  • Neoplasms / immunology
  • Neoplasms / therapy*
  • Swine
  • Transduction, Genetic

Substances

  • Capsid Proteins
  • GPI-Linked Proteins
  • Msln protein, mouse
  • hexon capsid protein, Adenovirus
  • Mesothelin

Grants and funding

Eberle Ovarian Cancer Fund and The Family Rock Ovarian Cancer Fund (FamiliesROC): MP and DM received these funds. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.