Tankyrase inhibition promotes a stable human naïve pluripotent state with improved functionality

Area of Science:

• Stem Cell Biology
• Developmental Biology
• Epigenetics

Background:

• Human pluripotent stem cells (hPSCs) are vital for developmental biology but are unstable in standard naïve culture conditions.
• Classical mouse embryonic stem cell (ESC) 2i culture (WNT and MEK/ERK inhibition) is not optimal for hPSCs.

Purpose of the Study:

• To establish stable naïve pluripotent states for human pluripotent stem cells (hPSCs).
• To investigate the efficacy of a modified inhibition cocktail (LIF-3i) for reverting hPSCs to a preimplantation inner cell mass (ICM)-like state.

Main Methods:

• Utilized a LIF-3i culture system involving WNT, MEK/ERK, and tankyrase inhibition.
• Reverted conventional hESC and human induced pluripotent stem cell (hiPSC) lines to a naïve state.
• Assessed karyotype, genomic imprints, self-renewal, signaling dependencies, and transcriptional/epigenetic profiles.

Main Results:

• LIF-3i successfully reverted a broad repertoire of hPSCs to stable, ICM-like naïve states.
• Reverted hPSCs exhibited normal karyotypes, genomic imprints, and mouse ESC-like functional features.
• Tankyrase inhibition stabilized the naïve state by modulating WNT signaling, improving hiPSC reprogramming and differentiation capacity.

Conclusions:

• Stable naïve hPSCs can be generated using LIF-3i culture, offering a more robust pluripotent state.
• This method enhances the utility of hPSCs for regenerative medicine and disease modeling by improving pluripotency and reducing genetic variability.