Clinical scale zinc finger nuclease mediated gene editing of PD-1 in tumor infiltrating lymphocytes for the treatment of metastatic melanoma.

Several Sangamo BioSciences authors contributed to this important research.
Clinical scale zinc finger nuclease mediated gene editing of PD-1 in tumor infiltrating lymphocytes for the treatment of metastatic melanoma.
Beane JD¹, Lee G², Zheng Z³, Mendel M², Abate-Daga D⁴, Bharathan M³, Black M³, Gandhi N², Yu Z³, Chandran S³, Giedlin M², Ando D², Miller J², Paschon D², Guschin D², Rebar EJ², Reik A², Holmes MC², Gregory PD², P Restifo N³, Rosenberg SA³, Morgan RA⁵, Feldman SA³.

Abstract

Programmed cell death-1 (PD-1) is expressed on activated T cells and represents an attractive target for gene-editing of tumor targeted T cells prior to adoptive cell transfer (ACT). We used zinc finger nucleases (ZFNs) directed against the gene encoding human PD-1 (PDCD-1) to gene-edit melanoma TIL. We show that our clinical scale TIL production process yielded efficient modification of the PD-1 gene locus, with an average modification frequency of 74.8% (n=3, range 69.9 - 84.1%) of the alleles in a bulk TIL population, which resulted in a 76% reduction in PD-1 surface-expression. Forty to 48% of PD-1 gene-edited cells had biallelic PD-1 modification. Importantly, the PD-1 gene-edited TIL product showed improved in vitro effector function and a significantly increased polyfunctional cytokine profile (TNFα, GM-CSF and IFNγ) compared to unmodified TIL in two of the three donors tested. In addition, all donor cells displayed an effector memory phenotype and expanded approximately 500 - 2000 fold in vitro. Thus, further study to determine the efficiency and safety of adoptive cell transfer using PD-1 gene-edited TIL for the treatment of metastatic melanoma is warranted.Molecular Therapy (2015); doi:10.1038/mt.2015.71.