Targeted biallelic integration of an inducible Caspase 9 suicide gene in iPSCs for safer therapies

verfasst von

Stephanie Wunderlich, Alexandra Haase, Sylvia Merkert, Kirsten Jahn, Maximillian Deest, Helge Frieling, Silke Glage, Wilhelm Korte, Andreas Martens, Andreas Kirschning, Andre Zeug, Evgeni Ponimaskin, Gudrun Göhring, Mania Ackermann, Nico Lachmann, Thomas Moritz, Robert Zweigerdt, Ulrich Martin

Abstract

Drug-inducible suicide systems may help to minimize risks of human induced pluripotent stem cell (hiPSC) therapies. Recent research challenged the usefulness of such systems since rare drug-resistant subclones were observed. We have introduced a drug-inducible Caspase 9 suicide system (iCASP9) into the AAVS1 safe-harbor locus of hiPSCs. In these cells, apoptosis could be efficiently induced in vitro. After transplantation into mice, drug treatment generally led to rapid elimination of teratomas, but single animals subsequently formed tumor tissue from monoallelic iCASP9 hiPSCs. Very rare drug-resistant subclones of monoallelic iCASP9 hiPSCs appeared in vitro with frequencies of ∼ 3 × 10^-8. Besides transgene elimination, presumably via loss of heterozygosity (LoH), silencing via aberrant promoter methylation was identified as a major underlying mechanism. In contrast to monoallelic iCASP9 hiPSCs, no escapees from biallelic iCASP9 cells were observed after treatment of up to 0.8 billion hiPSCs. The highly increased safety level provided by biallelic integration of the iCASP9 system may substantially contribute to the safety level of iPSC-based therapies.

Organisationseinheit(en)

Institut für Organische Chemie

Externe Organisation(en)

Medizinische Hochschule Hannover (MHH)

Typ

Artikel

Journal

Molecular Therapy - Methods and Clinical Development

Band

26

Seiten

84-94

Anzahl der Seiten

11

ISSN

2329-0501

Publikationsdatum

08.09.2022

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Molekularmedizin, Molekularbiologie, Genetik

Ziele für nachhaltige Entwicklung

SDG 3 – Gute Gesundheit und Wohlergehen

Elektronische Version(en)

https://doi.org/10.1016/j.omtm.2022.05.011 (Zugang: Offen)