Alpharetroviral self-inactivating vectors produced by a superinfection-resistant stable packaging cell line allow genetic modification of primary human T lymphocytes

Biomaterials. 2016 Aug;97:97-109. doi: 10.1016/j.biomaterials.2016.04.019. Epub 2016 Apr 26.

Abstract

Primary human T lymphocytes represent an important cell population for adoptive immunotherapies, including chimeric-antigen and T-cell receptor applications, as they have the capability to eliminate non-self, virus-infected and tumor cells. Given the increasing numbers of clinical immunotherapy applications, the development of an optimal vector platform for genetic T lymphocyte engineering, which allows cost-effective high-quality vector productions, remains a critical goal. Alpharetroviral self-inactivating vectors (ARV) have several advantages compared to other vector platforms, including a more random genomic integration pattern and reduced likelihood for inducing aberrant splicing of integrated proviruses. We developed an ARV platform for the transduction of primary human T lymphocytes. We demonstrated functional transgene transfer using the clinically relevant herpes-simplex-virus thymidine kinase variant TK.007. Proof-of-concept of alpharetroviral-mediated T-lymphocyte engineering was shown in vitro and in a humanized transplantation model in vivo. Furthermore, we established a stable, human alpharetroviral packaging cell line in which we deleted the entry receptor (SLC1A5) for RD114/TR-pseudotyped ARVs to prevent superinfection and enhance genomic integrity of the packaging cell line and viral particles. We showed that superinfection can be entirely prevented, while maintaining high recombinant virus titers. Taken together, this resulted in an improved production platform representing an economic strategy for translating the promising features of ARVs for therapeutic T-lymphocyte engineering.

Keywords: Alpharetroviral SIN vector; CRISPR-Cas9; Immunotherapy; Stable packaging cell line; Superinfection; TK007.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alpharetrovirus / metabolism*
  • Base Sequence
  • CRISPR-Cas Systems / genetics
  • Clone Cells
  • Genes, Reporter
  • Genetic Techniques*
  • Genetic Vectors / metabolism*
  • HEK293 Cells
  • Humans
  • Jurkat Cells
  • Reproducibility of Results
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*
  • Transduction, Genetic
  • Transgenes
  • Virus Assembly*