A UTF1-based selection system for stable homogeneously pluripotent human embryonic stem cell cultures

Area of Science:

• Stem cell biology
• Developmental biology
• Genetics

Background:

• Undifferentiated transcription factor 1 (UTF1) is a marker of pluripotency in embryonic stem cells.
• UTF1 expression ceases upon differentiation, offering a distinct marker compared to Oct4 or Nanog.
• Human embryonic stem cells (hESCs) are crucial for regenerative medicine but require precise control during culture and differentiation.

Purpose of the Study:

• To develop a novel selection system for human embryonic stem cells (hESCs) utilizing the UTF1 promoter.
• To assess the impact of the UTF1-driven selection system on hESC homogeneity, pluripotency, and differentiation potential.
• To evaluate the utility of this system for stem cell applications and somatic cell reprogramming.

Main Methods:

• Generation of two transgenic hESC lines (ZUN) with a UTF1 promoter driving a resistance gene.
• Culture of ZUN and parental HUES8 cells under selection pressure.
• Assessment of cell homogeneity, pluripotency marker expression (Oct4, Sox2), and differentiation capacity in vitro and in vivo (mouse teratoma model).

Main Results:

• Transgenic hESC lines (ZUN) exhibited high homogeneity under selection.
• ZUN cultures showed a higher proportion of Oct4 and Sox2 positive cells compared to controls.
• ZUN cultures maintained trilineage differentiation potential but displayed increased refractoriness to in vitro differentiation cues.
• The entire selection cassette is small (2.4 kb).

Conclusions:

• The UTF1 promoter-driven selection system effectively generates homogeneous hESC cultures.
• This system enhances pluripotency marker expression and maintains differentiation capacity.
• The UTF1 selection system is a powerful tool for stem cell applications and somatic cell reprogramming.
• The compact size of the selection cassette facilitates its use in various stem cell strategies.