Pharmacokinetic study of neural stem cell-based cell carrier for oncolytic virotherapy: targeted delivery of the therapeutic payload in an orthotopic brain tumor model

Cancer Gene Ther. 2012 Jun;19(6):431-42. doi: 10.1038/cgt.2012.21. Epub 2012 May 4.

Abstract

Oncolytic virotherapy is a promising novel therapy for glioblastoma that needs to be optimized before introduced to clinic. The targeting of conditionally replicating adenoviruses (CRAds) can be improved by relying on the tumor-tropic properties of neural stem cells (NSCs). Here, we report the characterization of an FDA approved NSC, HB1.F3-CD, as a cell carrier for CRAd-S-pk7, a glioma-tropic oncolytic adenovirus. We show that NSCs replicate and release infectious CRAd-S-pk7 progeny capable of lysing glioma cell lines. Moreover, ex-vivo-loaded NSCs, injected intracranially in nude mice bearing human glioma xenografts (i) retained their tumor tropism, (ii) continued to replicate CRAd-S-pk7 for more than a week after reaching the tumor site and (iii) successfully handed off CRAd-S-pk7 to glioma cells in vivo. Delivery via carrier cells reduced non-specific adenovirus distribution in the mouse brain. Moreover, we assessed biodistribution of loaded NSCs after intracranial injection in animal models semi-permissive to adenovirus replication, the Syrian hamster and cotton rat. NSCs did not migrate to distant organs and high levels of CRAd-S-pk7 DNA were observed only in the injected hemisphere. In conclusion, this optimized carrier system, with high efficiency of adenovirus delivery and minimal systemic toxicity, poses considerable advantages for anti-glioma oncolytic virotherapy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Adenoviridae / physiology*
  • Adenovirus E1A Proteins / biosynthesis
  • Adenovirus E1A Proteins / genetics
  • Animals
  • Brain / pathology
  • Brain / virology
  • Brain Neoplasms / therapy*
  • Cell Line
  • Cell Survival
  • Cricetinae
  • Disease Models, Animal
  • Glioma / therapy*
  • Green Fluorescent Proteins / biosynthesis
  • Humans
  • Luciferases, Firefly / biosynthesis
  • Male
  • Mice
  • Mice, Nude
  • Neoplasm Transplantation
  • Neural Stem Cells / transplantation*
  • Oncolytic Virotherapy / methods*
  • Oncolytic Viruses / genetics
  • Oncolytic Viruses / physiology*
  • Organisms, Genetically Modified
  • Recombinant Proteins / biosynthesis
  • Sigmodontinae
  • Viral Load
  • Virus Replication

Substances

  • Adenovirus E1A Proteins
  • Recombinant Proteins
  • Green Fluorescent Proteins
  • Luciferases, Firefly