Derivation of Naïve Human Embryonic Stem Cells Using a CHK1 Inhibitor.

Area of Science:

• Developmental Biology
• Stem Cell Biology
• Genetics

Background:

• Human embryonic stem cells (hESC) exhibit distinct pluripotent states (naïve and primed).
• Understanding these states is crucial for modeling early human development.
• Current methods for establishing hESC can be inefficient and yield chromosomally abnormal cells.

Purpose of the Study:

• To enhance the establishment of karyotypically normal late naïve hESC from frozen human blastocysts.
• To investigate the plasticity of these established hESC, including their ability to transition between pluripotent states.

Main Methods:

• Cryopreservation and thawing of human blastocysts.
• Treatment of thawed blastocysts with a checkpoint kinase 1 (CHK1) inhibitor.
• Establishment and culture of human embryonic stem cells (hESC).
• Transcriptional analysis to define pluripotent stages.

Main Results:

• Exposure to a CHK1 inhibitor upon thawing significantly improved the establishment of normal late naïve hESC.
• The established late naïve hESC demonstrated plasticity, allowing reversion to early naïve and progression to early primed states.
• Early primed hESC derived from this method are transcriptionally similar to the post inner cell mass intermediate (PICMI) stage and are more stable.

Conclusions:

• Checkpoint kinase 1 inhibition is a promising strategy for improving hESC derivation from frozen embryos.
• This method yields versatile hESC lines that recapitulate key developmental transitions.
• The findings offer a new avenue for studying early human development and stem cell differentiation.