Telomere-Associated Proliferative Capacity in Expandable Porcine Hepatocyte-like Progenitor Cells

Area of Science:

• Cell Biology
• Stem Cell Research
• Xenotransplantation Models

Background:

• Primary hepatocytes have limited proliferative capacity and lifespan, hindering long-term in vitro studies.
• GGTA1 knockout pigs offer a large-animal model with reduced immunogenicity for regenerative medicine applications.

Purpose of the Study:

• To generate expandable hepatocyte-like progenitor cells from GGTA1 knockout pigs.
• To establish a renewable in vitro system for liver biology, drug metabolism, and toxicity studies.

Main Methods:

• Direct reprogramming of porcine fibroblasts using a non-integrative episomal system encoding hepatic transcription factors.
• Transcriptomic and chromosomal analyses to assess cell identity, stability, and proliferative capacity.
• Evaluation of telomere length and expression of key proliferation-associated genes (TERT, MYC, CDKN1A).

Main Results:

• Successfully generated expandable hepatocyte-like progenitor cells exhibiting characteristic morphology and gene expression.
• Demonstrated sustained proliferative capacity linked to telomere maintenance and altered expression of proliferation regulators.
• Observed vector-dependent differences in genomic stability, including increased aneuploidy in codon-optimized cells.

Conclusions:

• Expandable hepatocyte-like progenitor cells derived from GGTA1 knockout pigs provide a promising renewable in vitro model.
• These cells partially recapitulate hepatocyte functions, enabling advanced studies in liver biology and drug development.
• A trade-off exists between proliferative capacity and genomic integrity, requiring further investigation for long-term applications.