Dual-patterned pluripotent stem cells self-organize into a human embryo model with extended anterior-posterior...

Area of Science:

• Developmental Biology
• Stem Cell Biology
• Human Embryogenesis

Background:

• Human gastruloids model early embryonic development but lack anterior structures and axial organization.
• Existing models do not fully recapitulate the coordinated development of the human body axis.

Purpose of the Study:

• To develop a novel human gastruloid model that incorporates both anterior and posterior embryonic features.
• To create a platform for studying early human body axis formation and neural development.

Main Methods:

• Pre-patterning human pluripotent stem cells (hPSCs) with anterior (FGF2) or posterior (CHIR99021 & retinoic acid) cues.
• Mixing dual-patterned hPSCs to promote self-organization into anterior-posterior (AP) human gastruloids.
• Utilizing single-cell RNA sequencing (scRNA-seq) for detailed cell type and regionalization analysis.

Main Results:

• AP human gastruloids self-organized into elongated structures with anterior and posterior features, including brain-like domains and segmented somites.
• scRNA-seq identified cell types resembling midbrain-hindbrain boundary, rhombomeres, and cranial neural crest.
• The model closely resembles Carnegie stage 11 primate embryos, recapitulating key neurulation and somitogenesis events.

Conclusions:

• AP human gastruloids provide a robust, scalable model for coordinated human anterior-posterior body axis development.
• This "pattern-and-mix" strategy offers a generalizable framework for assembling spatially organized stem cell models.
• The model's ability to phenocopy neural tube defects highlights its potential for studying congenital disorders.